Generator Protection Types and an Example Settings

The following are the main protection schemes adopted for our generator.

1. Generator Differential Protection
2. Generator & Transformer Differential Protection
3. Loss of Field or Loss of Excitation Protection
4. Negative Sequence or Current Unbalance Protection
5. Over Fluxing or Over Excitation Protection
6. Over Current Protection
7. Stator Earth Fault Protection
8. Rotor Earth Fault Protection (64R)
9. Restricted Earth Fault Protection
10. Backup Impedance Protection
11. Low Forward Power Protection
12. Reverse Power Protection
13. Pole Slip Protection
14. Pole Discrepancy Protection
15. Local Breaker Back Protection
16. Bus Bar Protection
17. Over Frequency Protection
18. Under Frequency Protection
19. Over Voltage Protection


1.GENERATOR DIFFERENTIAL PROTECTION:
Setting : 0.5 Amp Time : Instantaneous
It is one of the important protections to protect generator winding against internal faults such as phase-to-phase and three phase-to-ground faults. This type of fault is very serious because very large current can flow and produce large amounts of damage to the winding if it is allowed to persist. One set current transformers of the generator on neutral and phase side, is exclusively used for this protection. The differential protection can not detect turn-to-turn fault and phase to ground within one winding for high impedance neutral grounding generator such as ours. Upon the detection of a phase-to-phase fault in the winding, the unit is tripped with out time delay.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.

Once the differential protection operated, the unit can not be taken into service unless the generator winding is thoroughly examined by the maintenance staff of any internal faults

2.GENERATOR-TRANSFORMER DIFFERENTIAL PROTECTION :
Setting : 0.75 Amp Time : Instantaneous
It protects 11KV bus duct, 11/0.440KV unit auxiliary transformer, 11/20KV step-up transformer against internal faults such as phase-to-phase and three phase-to-ground faults. This type of fault is very serious because very large current can flow and produce large amounts of damage to the winding if it is allowed to persist. One set current transformers of the generator on neutral side and another set current transformer on 220KV side after transformer, is exclusively used for the protection. Upon the detection of difference in current between these current transformers, the unit is tripped with out time delay.One the generator-transformer differential protection operated, the unit can not be taken into service unless the 11KV bus duct, unit auxiliary transformer, power transformer are thoroughly examined by the maintenance staff for any internal faults.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.


3.LOSS OF FIELD OR EXCITATION PROTECTION :
Setting : K1-2, K2-1, K3-2 Trip after 2 Sec.
When the synchronous machine with excitation, is connected to the grid, it generates reactive power along with active power to the grid and the rotor speed is same as that of grid frequency. Loss of field or loss of excitation results in loss of synchronism between rotor flux & stator flux. The synchronous machine operates as an induction machine at higher speed and draws reactive power from the grid. This will result in the flow of slip frequency currents in the rotor body as well as severe torque oscillations in the rotor shaft. As the rotor is not designed to sustain such currents or to withstand the high alternating torques which results in rotor overheating, coupling slippage and even rotor failure.
A loss of excitation normally indicates a problem with the excitation system. Some times it may be due to inadvertent tripping of filed breaker, open or short circuit of field winding or loss of source to the exciter. If the generator is not disconnected immediately when it loses excitation wide spread instability may very quickly develop and major system shutdown may occur.
When loss of excitation alarm annunciates at annunciation panel, the machine may probably be running with less excitation at leading MVAR power. Increase the excitation on the machine until it reaches on lagging MVAR power. The machine trips on the same protection along with alarm resynchronize the machine and try to stabilize at required MVAR power. If not possible, trip the machine immediately and inform to the maintenance staff for thorough checking of the Automatic Voltage Regulator (AVR) and its associated parts.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.

4.NEGATIVE SEQUENCE OR CURRENT UNBALANCE PROTECTION :
Setting : Alarm – 75% of 12s Time - 5 Sec.
Trip – 75% of 12s Time - 300 Sec.
When the machine delivering the equal currents in three phases, no unbalance or negative phase sequence current is produced as the vector sum of these currents is zero, when the generator is supplying an unbalanced load to a system, a negative phase sequence current is imposed on the generator. The system unbalance may be due to opening of lines, breaker failures or system faults. The negative sequence current in the stator winding creates a magnetic flux wave in the air gap which rotates in opposite direction to that of rotor synchronous speed. This flux induces currents in the rotor body, wedges, retaining rings at twice the line frequency. Heating occurs in these areas and the resulting temperatures depend upon the level and duration of the unbalanced currents. Under these conditions it is possible to reach temperatures at which the rotor material no longer contain the centrifugal forces imposed on them resulting in serious damage to the turbine-generator set. Any machine as per design data will permit some level of negative sequence currents for continuous period.
An alarm will annunciate at annunciation panel if negative sequence currents exceeds a normal level. Reduce the MVAR power on the machine if necessary load also and keep the machine for some time till the alarm vanishes at annunciation panel. If the machine trips on the Negative sequence protection never take the machine into service until the temperatures on the rotor parts settle down to its lower value. Resynchronize the machine to the grid after considerable time under grid & feeder parameters are within limits. If the unit trips again on the same protection, stop the machine after consideration time so as to cool down the rotor parts and inform to the maintenance staff for thorough examination of the system.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
Status : a. Unit is at FSNL.

5. OVER FLUXING OR EXCITATION OR VOLTS PER HERTZ PROTECTION:
Setting : Alarm – 1.17 Time - 10 Sec.
Trip – 1.17 Time - 30 Sec.
Per unit voltage divided by per unit frequency commonly called Volts/Hertz is a measurable quantity that is proportional to flux in the generator or step-up transformer cores. Moderate over fluxing (105-110%) increases core loss resulting in increase of core temperatures due to hysterics & eddy currents loss. Long term operation at elevated temperatures can shorten the life of the stator insulation. Severe over fluxing can breakdown inter-laminar insulation followed by rapid local core melting. Over fluxing normally can be caused by over speed of the turbine or over excitation during Off-line condition, and load rejection or AVR mal-functioning during On-line condition.
If alarm annunciation panel, Increase/Reduce the speed of the turbine to rated generator speed (3000RPM) and reduce the generator voltage to rated during Off-line condition. Reduce the MVAR power on the generator during On-line condition. If the machine trips on over fluxing protection during On-line, Keep the machine at FSNL till the grid parameters stabilize and resins. Again the machine trips on the same stop the machine for examination of the AVR & Governor systems by maintenance staff.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.

6.OVER CURRENT WITH VOLTAGE RESTRAINT PROTECTION :
Setting : Alarm – 85% Time - 10 Sec.
Trip – 100% Time - 0.5 Sec.
Normally generators are designed to operate continuously at rated MVA, frequency and power factor over a range of 95 to 105% rated voltage. Operating the generator at rated MVA with 95% voltage, 105% stator current is permissible. Operating of the generator beyond rated KVA may result in harmful stator over current. A consequence of over current in winding is stator core over heating and leads to failure of insulation.
If alarm annunciates at annunciation panel, Reduce the stator current to the below the rated by reducing the MVAR power on the machine. When the trips on the same protection, Resins the machine after keeping the machine at FSNL for some time, and keep the stator current below the rated.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
Status : a. Unit is at FSNL.

7 STATOR EARTH FAULT PROTECTION :
Setting : 70% Time - 5 Sec.
Normally the generator stator neutral operates at a potential close to ground. If a faulty phase winding connected to ground, the normal low neutral voltage could rise as high as line-to-neutral voltage depending on the fault location. Although a single ground fault will not necessarily cause immediate damage, the presence of one increases the probability of a second. A second fault even if detected by differential relay, may cause serious damage. The usual method of detection fault is by measuring the voltage across the secondary of neutral grounding transformer (NGT). Here are two over lapping zones to detect stator ground faults in a high impedance grounded generator system, the two zones are put together cover 100% stator winding for earth faults. A fundamental frequency neutral over voltage relay covers about 0-95% of the stator zonal winding for all faults except those near the neutral. Another third harmonic neutral under voltage relay covers remaining 96-100% of the stator zone 2 winding on neutral side.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.

8.ROTOR EARTH FAULT PROTECTION (64R) :
Settings : Less than 80K ohm
Any rotor field winding of the generator is electrically isolated from the ground. Therefore the existence of one ground fault in the field winding will usually not damage the rotor. However the presence of two or more ground faults in the winding will cause magnetic and thermal imbalance plus localized heating and damage to the rotor metallic parts. The rotor earth fault may be caused due to insulation failure of winding or inter-turn fault followed by localized heat.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.

9.RESTRICTED EARTH FAULT PROTECTION:
Settings : 0.1 Amp. Time : Instantaneous
It is similar to generator differential protection in working. It protects the high voltage winding of 11/220KV power transformer against internal faults. One set current transformers of the power transformer on neutral and phase side, is exclusively used for this protection. The protection can not detect turn-to-turn fault within one winding. Upon the detection of a phase-to-phase or phase-to-ground fault in the winding, the unit to be tripped without time delay.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.
Once the restricted earth fault protection operated, the unit can not be taken into service unless the transformer winding is thoroughly examined by the maintenance staff for any internals faults. 

10.BACKUP IMPEDANCE PROTECTION:
Settings ; K1-3, K2-0.71 Time – 1.5 Sec.
As in name implies, it is used to protect the generator from supplying the over loaded or faulty system. It is backup protection of the generator over current protection. In measures ratio of the voltage and current supplied by the generator and initiates trip signal when the measured impedance is less than the preset value.
If the machine trips on the Backup protection, never take the machine into service until the temperatures of the generator settle down to its lower value. Resynchronize the machine to the grid after considerable time when grid & feeder parameters are within limits.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.

11.LOW FORWARD POWER PROTECTION:
Setting : 0.5% Time : 1 Sec.
The generator will not develop output power when turbine input is less than the no load losses and motoring action develops on the turbine. The generator is able to generate power, usually 55 to 10% of generator capacity, within pre-determined time after closing of 220KV breaker.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
Status : a. Unit is at FSNL with potential.
The unit trips on the low forward protection, Resins the machine and increase input power to the turbine as quickly as possible within low forward power time setting. Even after two to three attempts, the machine is tripping on the same protection; probably the governor of turbine is faulty. Inform to maintenance staff for rectification of the same.

12.REVERSE POWER PROTECTION:
Setting : 0.5% Time - 2.0 Sec.
It is backup protection to the low forward protection. Motoring of a generator will occur when turbine output is reduced such that it develops less than no-load losses while the generator is still on-line, the generator will operate as a synchronous motor and driving the turbine. The generator will not be harmed by synchronous motoring and a steam turbine can be harmed through over heating during synchronous motoring if continued long enough. The motoring of the turbine output can be detected by reverse power protection. The avoid false tripping due to power swings a time delay is incorporated before tripping signal is generated.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.
The unit trips on the reverse power protection. Resins the machine and increase the input power to the turbine as quickly as possible within low forward power time setting. Even after two to three attempts, the machine is tripping on the same protection; probably the governor of turbine is faulty. Inform to maintenance staff for rectification of the same.

13.POLE SLIP OR OUT-OF-STEP PROTECTION:
Setting : 6.9 ohm.
When a generator loses synchronism, the resulting high current peaks and off-frequency operation may cause winding stresses, pulsation torques and mechanical resonances that have the potential danger to turbine generator. Therefore, to minimize the possibility of damage, it is generally accepted that the machine should be tripped without time delay preferably during the first half-slip cycle of the loss of synchronism condition. The electrical center during loss-of-synchronous conditions can occur in the generator as a result of increased impedance of the generator while decrease system impedance. The protections normally applied in the generator zone such as back-up impedance, loss of excitation etc., will not protect a generator during loss of synchronism under normal generator conditions.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.
The unit trips on the Pole slip protection, Resynch the machine after stabilization of the grid parameters

14.POLE DISCREPANCY PROTECITON:
Setting : 0.5 Sec.
If One or two poles of generator breaker fail to close during synchronization, all poles of the breaker trip on this protection. It may be due to mechanical failure of the breaker un equal distribution of closing signal to the breaker from protection system.
Relays acted : a. Flag operation at 220KV Breaker panel.
b. Indication at Annunciation Panel.
Consequences : a. tripping of 220KV breaker
Status : a. Unit is at FSNL with potential.
The generator breaker trips on the pole discrepancy protection, Resynch the generator. Even after two to three attempts, the machine is tripping on the same protection, probably the generator breaker is faulty. Inform to maintenance staff for rectification of the same.

15.LOCAL BREAKER BACKUP PROTECTION:
Setting : 25% Time : 0.8 Sec.
For most of the faults, the generator breaker involves tripping the generator from the system. Failure of the breaker to open probably results in loss of protection and other problems such as motoring action or single phasing, If one or two poles of the generator breaker fail to open due to mechanical failure in breaker mechanism, the result can be a single phasing and negative phase sequence currents inducted on the rotor. The LBB protection is energized when the breaker trip is initiated after a suitable time interval if confirmation of the confirmation of breaker tripping from three poles is not received. The energized tripping signal from LBB protection will trip all 220KV generator breakers and all 220KV feeder breakers through Bus-bar protection.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay for all units.
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker of all units.
Status : a. all Units are at FSNL.
Once the LBB protection operated, the entire station is in dark. First restore all essential services to all units such as lube oil system and turning gear etc., from battery backup and. Checkup the faulty 220KV breaker and isolate the breaker from the system by opening the both side of the isolators.
After restoring all services from station supply, Close 220KV feeder breakers first and take all units into service one after the other duly co-coordinating with the DE/LD.
Since it involves complex operation, it is necessary to get help from maintenance staff for restoring the normally in the station. Never attempt to close the faulty 220KV generator in panic as it causes permanent damage to the generator and transformer.

16.BUS BAR PROTECTION:
Setting : 0.8 Amp.
There are mainly three protection zones namely called generator zone, bus duct transformer zone, 220KV breakers zone. The protection of generator zone and bus duct & transformer zone are covered in previous schemes. All 220KV breakers at switchyard will come under Bus-Bar protection. Functioning of this scheme is similar to the generator differential protection or generator-transformer differential protection. It measures all incoming currents from the generators at 220KV side and all outgoing currents in 220KV feeders, and initiates trip signal if it detects any deviation more than the preset value as the algebraic sum of all currents at 220KV bus must be less than the preset value. It isolates all 220KV generator breakers and all 220KV feeder breakers connected to 220KV bus.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay for all units.
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker of all units.
Status : a. all Units are at FSNL.
Once the Bus-Bar protection operated, the entire station is in dark. First restore all essential services to all units such as lube oil system and turning gear etc., from battery backup and 6.6/0.44KV Stage – II reserve power supply. Checkup the entire 220KV switch yard for any wire snapping or equipment damage.
After restoring all services from station supply, Close 220KV feeder breakers first and take all units into service one after the other duly co-ordinating with the DE/LD.
Since it involves complex operation, it is necessary to get help from maintenance staff for restoring the normalcy in the station. Never attempt to restore the 220KV supply at switch yard in panic unless the entire system is thoroughly examined and satisfy yourself as it causes permanent damage to the equipment or injury/death to the person working at switch yard.

17.OVER FREQUENCY PROTECTION:
Setting : 52 Hz Time - 2 Sec.
For a generator connected to a system, abnormal frequency operation is a result of a severe system disturbance. The generator can tolerate moderate over frequency operation provided voltage is within an acceptable limits. The machine operated at higher speeds at which the rotor material no longer contain the centrifugal forces imposed on them resulting in serious damage to the turbine-generator set. The abnormal over frequency on the machine may be due to improper speed control adjustment or disoperation of the speed controller or severe grid disturbance or sudden load through off.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker

c. Stop command to Turbine thro’ Mark-IV
Status : a. Unit is at coasting down.
The unit trips on the over frequency protection, Resins the machine. Even after two to three attempts, the machine is tripping on the same protection; probably the governor of turbine is faulty. Inform to maintenance staff for rectification of the same.

18.UNDER FREQUENCY PROTECTION:
Setting : 48 Hz Time : 2.0 Sec.
For a generator connected to a system, under frequency operation is a result of a severe system disturbance. The generator can tolerate moderate under frequency operation provided voltage is within an acceptable limits. The machine operated at lower higher speeds causes severe over fluxing in the generator-transformer. The abnormal under frequency on the machine may be due to improper speed control adjustment or disoperation of the speed controller.
Relays acted : a. Flag operation at Protection panel.
b. Indication at Annunciation Panel
Consequences : a. NIL
Status : a. Unit is at lower speed with potential.
Increase governor speed until machine reaches full speed. Even after two to three attempts, the machine are running at lower speed, probably the governor of turbine is faulty. Inform to maintenance staff for rectification of the same. 

19.OVER VOLTAGE PROTECTION :
Setting : a. 110% Time - 2.0 Sec.
b. 120% Time - 0.3 Sec.
Generator voltage is at present value under normal operating conditions as selected by operator in AVR. If it parts from preset value, May be due to AVR mal-functioning or a system disturbance. Severe over voltage can cause over fluxing and winding insulation failure. The over voltage protection can be considered as a backup to the Volts-per-Hertz protection.
Relays acted : a. Flag operation at Protection panel.
b. Acting of Master relay
c. Indication at Annunciation Panel.
Consequences : a. Tripping of 220KV breaker
b. Tripping of Field breaker
Status : a. Unit is at FSNL without potential.
Raise the generator voltage slowly with manual mode in AVR and keep generator voltage within the limits of normal voltage. If it is unable to control the generator voltage, trip the field breaker and inform to the maintenance staff for rectification of the AVR.

High Voltage Pulse Generators

Many applications require a repetitive source of high voltage pulses having fast rise and fall times. These applications include drivers for piezo-electric devices, ion tubes, gas tubes, liquid polarizing cells, beam steering applications, the generation of electric fields in aqueous solutions, and time-of-flight mass spectrometry measurements.

A high voltage pulse generator consists, essentially, of a high voltage power supply and a high voltage switch capable of alternately connecting and disconnecting this voltage source to a load. A simplified pulse generator is shown below. Here the high voltage supply charges a reservoir capacitor while the high voltage switch (HVS) is open. When HVS is closed, this reservoir capacitor rapidly supplies a pulse of current to charge the various capacitances (consisting of internal, cable, and load capacitances, as shown) to the full pulse amplitude and then, with the help of the power supply, supplies a steady current as determined by the load resistance to maintain this amplitude until HVS is again opened.

High Voltage Pulse Generators  in a Circuit

Although a high voltage pulse is the desired waveform, it is important to consider the current waveform required to produce this voltage pulse because it is this current waveform that sets important requirements on both the power supply and the high voltage switch. Current through the high voltage switch is a function of the sum of all internal, cable, and load capacitances and the load resistance. All three capacitances and the load resistance also have a significant impact on the rise and fall times of the pulse. A common problem with many users is in failing to consider these effects when specifying pulse operating requirements. Let’s consider a typical current waveform in more detail.

Component of Current Pulse

This current waveform consists of two parts: an initial sharp pulse and then a steady component. The sharp pulse of current, which determines the voltage pulse 10% to 90% rise time, has an average value as given by the following equation, where dV is the change in pulse amplitude during the rise time and dT is the rise time. As a rule of thumb, the peak current during the rise time is 2 to 3 times this average value.

Iaverage-rise = [Cinternal + Ccable + Cload] dV/dT

The surrent required to maintain the pulse amplitude across the load resistor is as follows, where R is the value of the load.

Iflat top = Pulse Amplitude / R

The 90% to 10% pulse fall time is given by the following equation:

Fall Time = 2.2 R [Cinternal + Ccable + Cload]

Consider this typical application. A 3.2 kV pulse generator with a 1 ns rise time and 12 pF of internal stray capacitance is connected to a Pockels Cell having a capacitance of 1 pF and a resistance of 10 M ohms via a 2-foot length of RG 114, 185 ohm coaxial cable. This cable has a capacitance of 6.5pF per foot when not terminated in its characteristic impedance. The values give:

Iaverage-rise = [12 pf +13 pf +1 pf] [3,200 volts / 1 ns] = 83.2 amps

Ipeak-rise ~ 160 amps

Iflat top = [3,200 volts / 10 M ohms] = 320 µa

Fall Time = 2.2[10 M ohms] [12 pf + 13 pf + 1 pf] = 572 µs

Therefore, to drive a 1 pF Pockels Cell, through 2 feet of 185 ohm cable, from 0 to 3.2 kV in 1 ns requires a peak current of approximately 160 A. The fall time is slow because the various capacitors are discharged through the 10 M ohms resistor when the high voltage switch is opened. The fall time may be made faster by using a shunt resistor across the cell terminals.

As an example, consider what happens when the cable is terminated in its characteristic impedance by adding a 185 ohm shunt resistor across the load. This reduces the current required during the pulse rise time dT by effectively eliminating the cable capacitance, increases the current required from the power suppluy to maintain the pulse amplitude, and reduces the pulse fall time.

Iaverage-rise = [12 pf +1 pf] [3,200 volts / 1 ns] = 41.6 amps

Ipeak-rise ~ 80 amps

Iflat top = [3,200 volts / 185 ohms] = 17 amps

Fall Time = 2.2[185 ohms] [12 pf + 1 pf] = 5.3 ns

Another technique that can be used to reduce the pulse fall time and minimize the effects of load and cable capacitance is to add another high voltage switch from the load to ground. When the first HVS is turned off this HVS is turned on, effectively discharging the load capacitance to ground, or “biting the tail” of the pulse. This generally results in a fall time that is less dependent on the load capacitance and resistance. The average pulse current is also decreased since a shunt resistor across the load is no longer required. The addition of the second switch increases the cost of the pulse generator and, in most cases, has a minimal effect on the rise time.

The HV Pulse 5k-2500 is an example of a pulse generator that utilizes a tail biter to control pulse fall time. This pulser is designed to drive the grid of a high power vacuum tube, which presents a large load capacitance. Assume a pulse amplitude 0-5 kV and a load that looks like 250 ohms in parallel with a total of 1450 pF. The design goal is to keep the pulse fall time below 200 ns. With no tail biter, the approximate fall time would be:

Fall Time = 2.2[250 ohms] [100 pf + 1450 pf] = 853 ns

When a tail biter consisting of a current-limiting resistor of 70 ohms in series with a second HVS is introduced across the load, the fall time is reduced to:

Fall Time = 2.2[250 ohms || 70 ohms] [100 pf + 1450 pf] = 187 ns

It is apparent that load capacitance, including cable capacitance, is a very important consideration in the design and application of high voltage pulsers. Depending on operating requirements, the effects of capacitance can be controlled in several ways: the length of the interconnecting cable can be made as short as possible, a shunt resistor can be added across the load, or a tail biter can be introduced into the circuit.

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Not only everyday fixes, like changing a burned out light bulb or faulty fuse aren't scary moments any more - you might also be able to cope with more complex problems with your computer etc. That doesn't only save you money but also works great as a pick up line...

9. New stuff gets out all the time - it never gets boring

Electrical and electronic components are modified, invented and reinvented every day, so you will never be bored because you are using same process or component for the last 10 years. New and exciting stuff is available all the time and you will have lots of fun testing an assembling it.

10. Only few simple rules to follow

    Things work better when plugged to power

    Electrical components work on smoke - when it gets out you are in trouble

    If things don't work, read a manual.

List of electrical engineers

This is a list of electrical engineers, people who made contributions to electrical engineering or computer engineering.

Who	Contribution(s)
Norman Abramson	ALOHAnet network communication
Edwin Armstrong	Regenerative circuit, frequency modulation (FM)
William Edward Ayrton	Measuring instruments, electric railways, searchlight
John Bardeen	Two Nobel prizes: transistor, superconductivity
Emile Baudot	Telegraphy communications
Andy Bechtolsheim	Cofounder of Sun Microsystems
Arnold Orville Beckman	pH meter, Beckman Instruments, Silicon valley pioneer
Alexander Graham Bell	Bell telephone company
Alfred Rosling Bennett	Pioneer of electric lighting and telephones
Harold Stephen Black	Negative feedback amplifier
Ottó Bláthy	Pioneering electrical engineer
André Blondel	Oscillography, electrical machine theory
Alan Blumlein	Inventions in telecommunications, sound recording, stereo, television, radar
Hendrik Wade Bode	Control theory, Bode plot
Paul Boucherot	Reactive power
Karlheinz Brandenburg	Audio compression scheme MP3
Charles Tilston Bright	Transatlantic cable
Charles Eugene Lancelot Brown	co-founder of Brown, Boveri & Cie
William C. Brown	crossed-field amplifier, microwave power transmission
Walter Bruch	Television pioneer, inventor of the PAL colour television system
Charles F. Brush	Efficient dynamos, electric lighting,founder of one of the General Electric companies, wind power
Charles Frederick Burgess	Batteries' development, pioneer of electrochemical engineering
Alan Archibald Campbell-Swinton	Theory of television
Marvin Camras	Magnetic recording
John Renshaw Carson	Single-sideband modulation
James Kilton Clapp	Clapp oscillator, General Radio Corporation
Lynn Conway	very large scale integrated circuit design, Mead & Conway revolution
William Coolidge	X-rays
William Corin	Snowy Mountains Scheme
R. E. B. Crompton	electric lighting, instruments, manufacturer
Seymour Cray	Supercomputer architect
Sidney Darlington	the Darlington transistor
Lee DeForest	Audion vacuum tube
Georges de Mestral	Velcro
Jack Dennis	time sharing, Multics
Robert H. Dennard	Dynamic random access memory
Marcel Deprez	HVDC power transmission pioneer
Bern Dibner	Founder Burndy Co., electrical connectors, historian of the Transatlantic cable
Mikhail Dolivo-Dobrovolsky	Inventor of three-phase motor
Ray Dolby	Dolby sound
William Duddell	Oscillography, the singing Arc lamp
Allen B. DuMont	television manufacturing pioneer
J. Presper Eckert	Computer pioneer
Thomas Edison	Prolific inventor: phonograph, first practical light bulb, telegraph improvements
Douglas Engelbart	computer mouse, hypertext
Justus B. Entz	Electric transmission,electric vehicles, worked with Edison
A. K. Erlang	Communications and Queueing
Lloyd Espenschied	Developments in radio communications and coaxial cable technology.
Federico Faggin	Intel microprocessor, Zilog z80
Michael Faraday	Discovered electromagnetic induction and Faraday shield
Moses G. Farmer	Electric railway
Philo T. Farnsworth	American television pioneer
Galileo Ferraris	Rotating magnetic field
Sebastian Ziani de Ferranti	Ferranti Corporation
Reginald Fessenden	"Father of Radio Broadcasting"
Donald G. Fink	Radio navigation LORAN, television standards, author
Gerhard Fischer	Handheld metal detector
John Ambrose Fleming	Inventor of the thermionic valve (vacuum tube)
Thomas Flowers	Designer of the first programmable digital electronic computer
Jay Forrester	American computer pioneer
Charles Legeyt Fortescue	symmetrical components for three-phase power system analysis
Jean Baptiste Joseph Fourier	Physicist; Fourier transform / Fourier series
Leonard F. Fuller	radio pioneer, carrier current on power systems
Dennis Gabor	Hungarian inventor of holography, Nobel Laureate
Zénobe Gramme	Dynamo
Elisha Gray	telephone pioneer
Richard Grimsdale	transistorized computers
Edward E. Hammer	Spiral Compact fluorescent lamp
Ralph Hartley	Electronics
Oliver Heaviside	Re-formulated Maxwell's equations (vector calculus)
Oskar Heil	field-effect transistor, loudspeaker
Heinrich Rudolf Hertz	Hertzian Waves
Peter Cooper Hewitt	Mercury vapor lamp, mercury arc rectifier
William Hewlett	Hewlett-Packard
Hugo Hirst	Co founder, General Electric Company plc
Godfrey Hounsfield	Inventor of the world's first computed tomography (CT) scanner, shared a 1979 Nobel prize
Edwin J. Houston	Arc lighting, cofounder of what would become General Electric, president of AIEE
John Hopkinson	Inventor of Three-phase electrical system
Grace Hopper	Computer programmer (first compiler)
Paul Horowitz	SETI, coauthor of The Art of Electronics
Lawrence A. Hyland	Radar pioneer, leader of Hughes Aircraft
Kees Schouhamer Immink	Pioneer optical recording, CD, DVD, Blu-ray Disc
Samuel Insull	Central station generation, electrical utilities, Edison Pioneer
Fleeming Jenkin	Submarine telegraph cables
Bill Joy	Unix - Sun Microsystems
Rudolf Kalman	Inventor of the Kalman filter
Kálmán Kandó	Pioneer of high voltage railway electrification systems
Nathaniel S. Keith	founding secretary AIEE; electric power
Arthur E. Kennelly	complex numbers in AC circuit theory
Charles Kettering	Automobile electrical innovations, Delco founder
Jack Kilby	Nobel prize: Integrated circuit
Max Knoll	Electron microscope
John D. Kraus	Radio telescope, antennas
Herbert Kroemer	Heterostructures and semiconductor physics
Eric Laithwaite	Linear induction motor
Hedy Lamarr	Communications
Uno Lamm	Swedish, HVDC and mercury arc valves
Benjamin G. Lamme	Niagara Falls power engineering
Georges Leclanché	primary battery
Morris E. Leeds	Leeds & Northrup measurement and control devices
Alexander Lodygin	Russian, incandescent lighting, motors
Östen Mäkitalo	Father of Cellular Phone
Guglielmo Marconi	Practical radio
Orlando R. Marsh	electrical sound recording
Erwin Otto Marx	Marx generator high voltage DC
John Mauchly	ENIAC designer
Charles Hesterman Merz	NESCO Electric power grid, England
William Henry Merrill	founder of Underwriters Laboratories
Robert Metcalfe	Ethernet, 3Com
John L. Moll	Solid-state physics, the Ebers-Moll transistor model
Robert Moog	Electronic music pioneer, invented Moog synthesizer
Daniel McFarlan Moore	electrical discharge lighting
Shuji Nakamura	blue gallium-nitride Light emitting diodes
Edward Lawry Norton	Norton's theorem
Robert Noyce	Co-founder of Fairchild Semiconductor and Intel
Bernard M. (Barney) Oliver	Hewlett-Packard, Founder HP Labs
Kenneth Olsen	Magnetic core memory; Digital Equipment Corporation
Stanford R. Ovshinsky	semiconductors
David Packard	Hewlett-Packard
Robert H. Park	Park's transformation
Donald Pederson	Father of SPICE
G. W. Pierce	oscillator, crystal control
William Henry Preece	Telegraphy, nemesis of Heaviside
Franklin Leonard Pope	telegraphy, electric lighting, Edison influence
Valdemar Poulsen	Magnetic recording
Michael I. Pupin	Long-distance telephone communication. "Pupin coil"
Simon Ramo	Physicist, microwaves, missiles, founder TRW and Bunker Ramo Corporation
Richard H. Ranger	wireless fax, radar, magnetic tape recording
Alec Reeves	Inventor of pulse code modulation
Johann Philipp Reis	Inventor of the Reis telephone
Hyman G. Rickover	"Father of the Nuclear Navy"
Edward S. Rogers, Sr.	Inventor of the first successful AC radio tube
Harold Rosen	Syncom communication satellite
H. J. Round	Radio pioneer and assistant to Guglielmo Marconi
Reinhold Rudenberg	Electron microscope
Carl Louis Schwendler	Electric lighting and telegraph
Thomas Johann Seebeck	Thermoelectric effect
Oliver B. Shallenberger	AC electricity meters
Claude Shannon	"Father of Communication Theory"
Ernst Werner von Siemens	Inventor, industrialist, Siemens & Halske, Siemens (unit)
Carl Wilhelm Siemens	Telegraphy, motors and generators, electric pyrometer
Alexander Siemens	Electric lighting, power, Society of Telegraph Engineers (predecessor to IEE)
Phillip Hagar Smith	Smith chart
Percy Spencer	Microwave oven
Frank J. Sprague	"Father of Electric Traction"
Chauncey Starr	Founder, Electric Power Research Institute
Charles Proteus Steinmetz	Alternating current theories
Sarkes Tarzian	Radio inventor, broadcasting, radio manufacturer
Albert H. Taylor	First demonstration of radar
Bernard D. H. Tellegen	inventor of the Pentode, formulated Tellegen's theorem
Nikola Tesla	Revolving magnetic field electric motor, Tesla coil, Polyphase transmission systems, transformer
Silvanus P. Thompson	Educator, author, electrical machinery, X-rays, radio
Elihu Thomson	Entrepreneur, co-founder of what would become General Electric
William Thomson (Lord Kelvin)	Telegraphic cables
René Thury	High voltage direct current power transmission, electric traction
Kálmán Tihanyi	Television pioneer
Charles Joseph Van Depoele	Electric railway pioneer
C. F. Varley	Submarine cable, Varley bridge
Milan Vidmar	Power transformers and transmission of electric current
Andrew Viterbi	Communications
Trevor Wadley	Innovations in radio and microwave technology
Harry Ward Leonard	Inventor of the Ward Leonard control system.
Robert Watson-Watt	First practical radar
George Westinghouse	AC power industrialist
Harold Alden Wheeler	Automatic volume control, radar
Uncas A. Whitaker	Founder of AMP Inc. and philanthropist
Bob Widlar	Integrated circuits
Niklaus Wirth	Computer programming languages
Steve Wozniak	Personal computers; Apple Computer
Pavel Yablochkov	Electric arc lighting
Jerry Yang	Co-Founder, Former CEO of Yahoo
Hidetsugu Yagi	Yagi-Uda antenna
Otto Julius Zobel	Filters
Konrad Zuse	Computers

Introduction to installing power cables

1. Open-Wire

Open-wire construction consists of uninsulated conductors on insulators which are mounted on poles or structures. The conductor may be bare or it may have a thin covering for protection from corrosion or abrasion. The attractive features of this method are its low initial cost and the fact that damage can be detected and repaired quickly.

On the other hand, the uninsulated conductors are a safety hazard and are also highly susceptible to mechanical damage and electrical outages resulting from short circuits caused by birds or animals. Proper vertical clearances over roadways, walkways, and structures are critical. Exposed open-wire circuits are also more susceptible to the effects of lightning than other circuits, however, these effects may be minimized by the use of overhead ground wires and lightning arresters.

In addition, there is an increased hazard where crane or boom truck use may be involved. In some areas contamination on insulators and conductor corrosion can result in high maintenance costs.

2. Aerial Cable

Aerial cable consists of fully insulated conductors suspended above the ground. This type of installation is used increasingly, generally for replacing open wiring, where it provides greater safety and reliability and requires less space.

Properly protected cables are not a safety hazard and are not easily damaged by casual contact.

They do, however, have the same disadvantage as open-wire construction, requiring proper vertical clearances over roadways, walkways, and structures.

2.1 Supports

Aerial cables may be either self-supporting or messenger-supported. They may be attached to pole lines or structures. Self-supporting aerial cables have high tensile strength for this application. Cables may be messenger-supported either by spirally wrapping a steel band around the cables and the messenger or by pulling the cable through rings suspended from the messenger.

2.2 Distance

Self-supporting cable is suitable for only relatively short distances, with spans in the range of 100-150 feet. Messenger-supported cable can span relatively large distances, of over 1000 feet, depending on the weight of the cable and the tensile strength of the messenger. For this reason, aerial cable that must span relatively large distances usually consists of aluminum conductors to reduce the weight of the cable assembly.

The supporting messenger provides high strength to withstand climatic rigors or mechanical shock. It may also serve as the grounding conductor of the power circuit.

3. Above-Ground Conduits

Rigid steel conduit systems afford the highest degree of mechanical protection available in above-ground conduit systems. Unfortunately, this is also a relatively high-cost system. For this reason their use is being superseded, where possible, by other types of conduit and wiring systems.

Where applicable, rigid aluminum, intermediate-grade steel conduit, thin-wall EMT, intermediate-grade metal conduit, plastic, fiber and asbestos-cement ducts are being used.

4. Underground Ducts

Underground ducts are used where it is necessary to provide a high degree of safety and mechanical protection, or where above-ground conductors would be unattractive.

4.1 Construction

Underground ducts use rigid steel, plastic, fiber, and asbestos-cement conduits encased in concrete, or precast multi-hole concrete with close fitting joints.

Clay tile is also used to some extent. Where the added mechanical protection of concrete is not required, heavy wall versions of fiber and asbestos-cement and rigid steel and plastic conduits are direct buried.

4.2. Cables

Cables used in underground conduits must be suitable for use in wet areas, and protected against abrasion during installation.

5. Direct Burial

Cables may be buried directly in the ground where permitted by codes and only in areas that are rarely disturbed. The cables used must be suitable for this purpose, that is, resistant to moisture, crushing, soil contaminants, and insect and rodent damage. While direct-buried cable cannot be readily added to or maintained, the current carrying capacity is usually greater than that of cables in ducts. Buried cable must have selected backfill.

It must be used only where the chance of disturbance is unlikely. The cable must be suitably protected, however, if used where the chance of disturbance is more likely to occur.

Relatively recent advances in the design and operating characteristics of cable fault location equipment and subsequent repair methods and material have diminished the maintenance problem.

6. Underwater (Submarine) Cable

Submarine cable is used only when no other cable system can be used. It supplies circuits that must cross expanses of water or swampy terrain.

6.1 Construction

Submarine cable generally consists of a lead sheathed cable and is usually armored. Insulation material should be XLP or EPR, except when paper insulation is justified because of its high resistance to, and freedom from, internal discharge or corona.

Multiconductor construction should be used, unless limited by physical factors. The lead sheathing usually consists of a copper-bearing lead material, however, other alloys may be required when special conditions warrant nonstandard sheathing. The most common type of  armoring material used for submarine cables is the spirally wrapped round galvanized steel wire.

Standard applications for submarine power cables to connect mainland areas or cities via water passages. This applies to mainland-to-island connections. Many of these networks and connections are getting older and need to be overhauled. We are constantly working on the continuous refinement of these products to reduce environmental effects (precisely during the laying process) and losses during power transmission (using new materials).

In this type of cable, asphalt impregnated jute is usually applied over the lead sheath and the wire armor is applied over the jute to reduce mechanical damage and electrolytic corrosion. An additional covering of the asphalt impregnated jute may be applied over the wire armor.

Nonmetallic sheathed cables are sometimes suitable for certain submarine applications. The cable must be manufactured specifically for submarine service and, generally, has an increased insulation thickness. The cable may require wire armor and should have electrical shielding for all voltage ratings above 600 V.

6.1 Installation

Submarine cable should lie on the floor of the body of water and should have ample slack so that slight shifting caused by current or turbulence will not place excessive strain on the cable. Where the cable crossing is subject to flow or tidal currents, anchors are often used to prevent excessive drifting or shifting of the cable. In addition to laying cables directly on the bottom, burying cable in a trench using the jet water method should be considered.

Cables must be buried in waters where marine traffic is present. The depth of burial should be enough to prevent damage caused by dragging anchors, which may be in excess of 15 feet for large ships on sandy bottoms.

Warning signs located on shore at the ends of the submarine cable should be provided to prohibit anchoring in the immediate vicinity of the cable.

Electrical Engineering Seminar Topics

1. Energy Conservation by Soft Start 

2. Power System Contingencies 

3. Direct torque control of AC drives 

4. Servomotor Magnetic resonance imaging (MRI 

5. Mild Hybrid Electric Vehicle 

6. Non conventional source (biomass 

7. Geothermal Energy 

8. Reactive Power Consumption in Transmission Line 

9. Pace maker 

10. Computer Clothing 

11. Robotics and its application 

12. Synchronous voltage source 

13. Space Solar Power 

14. Laser and its application 

15. Surge Arrestor 

16. Liquid Electricity 

17. Field oriented control drives without shaft sensors 

18. Hydrogen Fuel cell 

19. Fast Breeder Reactor 

20. Stepper Motor 

21. Single phase neutral point clamped AC/shos converter with power factor corrector and active filter 

22. Nano Wire 

23. High-Temperature Nuclear Reactors for Space Applications 

24. Medical Imaging Techniques 

25. Homo Polar Generator 

26. Transducer 

27. Maglev Train 

28. Automatic solar tracker 

29. Surge Protection in Modern Devices 

30. Load Monitoring 

31. Ultra sonic motor 

32. Effect on generating units caused by loss of excitation 

33. Ultra capacitors 

34. Remote Monitoring and Thought inference 

35. PWM technique applied to induction motor 

36. Expert Technician System 

37. Plastic chips 

38. Missile Technology 

39. Interactive Voice Response System 

40. Permanent magnet D C Motor 

41. Solar hybrid pvt systems 

42. Neural Networks application in Induction motor 

43. Bridge capacitor bank in EHV system 

44. Energy Efficient Motor 

45. Advancements in inverter technology for industrial applications 

46. Gas Insulated Transformer 

47. Gyro bus 

48. Ultrasonic sound detection and its applications 

49. Solar Ponds 

50. Electrostatic Generator 

51. Power System Solvability 

52. Automation of temp rise test for L T Switch gear 

53. Micro Fuel Cells 

54. Power Factor Correction 

55. Evacuated Tube Solar Collector 

56. Energy Storage within a Hydrogen Transportation Fuel Infrastructure 

57. Electrical Energy Management & Audit 

58. E-nose 

59. Installation Maintenance and application of power transformer 

60. Secure User Authentication using Automated Biometrics 

61. Speed Detection Camera 

62. Direct Broadcast Satellite 

63. Production of & Protection against Surge 

64. Implementation of PLC 

65. Automatic Circuit Recloser 

66. Flywheel Energy Storage 

67. Satellite Radio 

68. Uninterrupted Power Supply 

69. Superconductivity 

70. 66kv Receiving Sub-Station 

71. Availability based tariff scheme 

72. Magnetic Resonance imaging 

73. Artificial Neural Network 

74. DC circuit breaker 

75. Arc Fault Circuit Interrupters 

76. HVDC Converter 

77. Load Shedding 

78. D C Arc Furnace 

79. DSP (Digital Signal process Based Motor Control System) 

80. Integrated Gate Commutated Thyristor 

81. Vector control Of Induction Motor 

82. Energy Saving Motor 

83. Prepaid Energy meter 

84. Smartcard 

85. Power line carrier communication 

86. Multiterminal D C supply (MTDC 

87. Flexible Photovoltaic Technology 

88. Geothermal Power Stations 

89. Coal IGCC power production 

90. Wire less power transmission 

91. Condition Based Maintenance of UG Cable Systems 

92. Flexible AC transmission System 

93. Wind Power 

94. Cathodic Protection 

95. Fuel Cells 

96. Virtual Instrumentation 

97. Stirling Radioisotope Generator (SRG 

98. ome Automation 

99. PMDC Motor 

100. Integrated Vehicle Health Management Technology 

101. Solar Tower Technology 

102. Conditional monitoring 

103. Protection of overhead transmission against lighting 

104. Super conductor 

105. Remotely Queried Embedded Microsensors 

106. Electric Locomotive 

107. Fuzzy logic 

108. Fibre Optic Communication 

109. In-Memory Database 

110. Electrical & Electromagnetic interferance 

111. Condition Based Maintenance of Underground Cable Systems 

112. wind power generation 

113. Electrical vehicles 

114. ELECTRICAL 

115. Failure of Distribution Transformer 

116. Narrowband Powerline Communication 

117. Bluetooth? Wireless Technology 

118. Distributed Generation 

119. Data Compression 

120. Automated distribution system 

121. Micro electro-mechanical system 

122. HVDC back to back converter & transformer 

123. Utilization Of Solar Energy 

124. 33 KV gas insulated switchgear 

125. Cluster Meter System 

126. Geothermal 

127. Metamorphic Robots 

128. Faraday's Disk Generator 

129. Fuel cell vehicle 

130. Load sharing between the inverters operating 

131. Brush less DC motor 

132. Axial-field electrical machines 

133. Fusion 

134. Expert system as applied to power system 

135. RPM's flywheel power storage system 

136. Feeder protection 

137. Context Disambiguation on Web Search Results 

138. Tiny Switch 

139. Traction System 

140. Super Conducting Magnetic Energy Storage Systems 

141. H V D C converter 

142. Organic LED 

143. Biomedical Instruments (EEG 

144. Earth leakage circuit breaker 

145. MPEG Video Compression 

146. Energy conservation 

147. Direct torque Control Method for Speed control of Induction Motor 

148. Hydrogen The Future Fuel 

149. Static excitation system for alternator 

150. Architecture of an Electric Vehicle 

151. Nano Fuel Cell 

152. A report on series compensation 

153. Modern trends in thermal power station 

154. AVR in Alternator 

155. Blue ray Disc Technology 

156. Electromagnetic Bomb 

157. Fuel cell & Fuel cell power plant 

158. Advanced less-flammable transformer Insulating Fluid 

159. Power system relability 

160. Artificial intelligence in power station 

161. Automatic Change Over with Current Limiter 

162. RFID Systems 

163. Asynchronous systems 

164. Tele-Immersion 

165. Laser based application 

166. Static starting device 

167. Prediction of the closest margin to restore Power System Solvability 

168. 66 KV receiving station design 

169. Optical var Control 

170. Bioinformatics 

171. Tidel Power plant 

172. Digital Testing of High Voltage Circuit Breakers 

173. Micro Electro Mechanical Systems (REMEMS 

174. Static Relay 

175. Development Status of Superconducting Rotating Machines 

176. BiCMOS Technology 

177. Cable Modems 

178. Internet Protocol Television 

179. Storage battries 

180. Power supply for electrical traction drives 

181. Green Power 

182. Distributed Control System 

183. H V tester 

184. PLC 

185. Power Grid 

186. Supervisory control and data acquisition (SCADA systems in power stations) 

187. Power Theft Identification 

188. Micro stepping of stepper motor and application 

189. Night Vision 

190. PPTC Devices 

191. FACTS 

192. Explosive Flux Compression Generator 

193. Energy Saving Tube Light 

194. Power quantity standards 

195. Thermoelectric Coolers 

196. Automatic Meter Reading 

197. Phase Locked Loop 

198. Stenography 

199. Cryptography 

200. Magnetic Train 

201. Decentralized power sources 

202. Cable fault localization 

203. Public Key Encryption and Digital Signature 

204. Hybrid Electrical vehicles 

205. Superconducting Generator 

206. Performance Evaluation & EMI/EMC Testing of Energy Meter 

207. Static starting device for gas turbine 

208. Power frequency magnetic fields 

209. Electrolytic Hydrogen: A Future Technology for Energy Storage 

210. Solar cell 

211. Energy Audit 

212. Vector control of an induction motor 

213. Spintronics 

214. Molecular surgery 

215. Power distribution grid 

216. HVDC Technology 

217. Microprocessor based power theft identification 

218. Transient over voltages in electrical distribution system and suppression techniques 

219. Wireless power transmission 

220. Membrane Switch 

221. Extra high voltage transmission line 

222. Biometric Fingerprint Identification 

223. Stepper Motor & its Application 

224. Deregulation Of Energy Sector & [censored] Determination 

225. Renewable Energy Source Biomass 

226. Upgrading generator protection using multiple replay 

227. Electric field optimization of high voltage electrode based on neural network 

228. Line Reactors 

229. Relay Performance Testing With High Technology 

230. Two phase Neural Network 

231. Margin to restore Power System Solvability 

232. Contact less energy transfer system 

233. Matteran Energy 

234. Impacts of harmonics on power quality 

235. Protection through switchyard equipment 

236. Ultracapacitors 

237. Biosensors 

238. A technique for on-line detection of shorts in fields of turbine generator rotor 

239. Non conventional source (Geothermal 

240. 66 K V Switch Yard 

241. Broadband Over Power Line (BPL 

242. Perceptive computing 

243. Voltage Sag Analysis 

244. Terrestrial Photovoltaics (PVs 

245. Home Electrical Device Control HOWTO 

246. Satellite Television 

247. Neutral networks in process control 

248. Wireless fidelity 

249. Different Type of Excitation scheme on alternator 

250. Transformer Oil 

251. Buck Boost Transformer 

252. Dust collection & scrubing tech 

253. Herd coating Technology 

254. Solar power generation 

255. Less Flammable Transformer Insulating Fluids 

256. Modeling of Transformers with Internal Incipient Faults 

257. E H V transmission lines 

258. DC UPS 

259. Energy convection tower 

260. Power electronics 

261. Electrical fuses & its Application 

262. Speed control of DC shunt Motor Using PWM 

263. Introduction of Batteries 

264. Electrical Fuses, its types & Applications 

265. Maximum power point tracking 

266. Prospects Of Nanotechnology 

267. Fiber Optic Sensors 

268. Circuit Breaker Switching & Arc Modeling 

269. Lightning Protection Using LFA-M 

270. Medical imagining techniques 

271. High-Availability Power Systems 

272. Polymeric Positive Temperature Coefficient (PPTC 

273. Improving Electrical System Reliability with Infrared Thermography 

274. Hydrogen fuel cell in India 

275. Electroencephalogram 

276. Fuel Cells on Aerospace 

277. MOCT (Magnetic Optical Current Transformer 

278. Sensor less speed estimation of I M 

279. Operation & Maintenance of Substation 

280. Fault prediction & diagnoses 

281. Optical Antenna 

282. Satellite Solar power 

283. Alternator synchronization 

284. Electric cars 

285. Electronics Ballast 

286. Control of excitation system 

287. Protection of Distribution System 

288. Power system stability 

289. Superconducting Rotating Machines 

290. Position Emission Tomography 

291. Power factor improvement 

292. Fusion Technology 

293. Nanotechnology-Fueling the Chemical Industry?s Future 

294. Infrared Thermography 

295. Gas insulated Substations (GIS 

296. H V Testing of Circuit Breaker 

297. Solar Battery Storage Pump 

298. Flexible AC transmission 

299. Telluri Current 

300. Synchronization of alternator with grid 

301. Maintenance of Distribution Transformer 

302. Renewable energy 

303. Fractal Image Compression 

304. Testing of 3 phase induction motor and trouble shooting 

305. Radio Frequency Identification Sensors 

306. High voltage testing of Transformer 

307. Switched Reluctance Motor 

308. Pyroelectric Fusion 

309. Solar electric vehicles 

310. Hydrogen as an alternative fuel 

311. Compensation of Harmonic Currents Utilizing AHC 

312. Variable speed drives 

313. Combined cycle power plant 

314. Direct to Home 

315. Transformer Protection 

316. ISDN 

317. E-commerce 

318. Wavelet Transforms 

319. Lighting 

320. Fault location in Grounded and High resistance Grounded systems 

321. Distribution system relaying 

322. Magnetoencephalography 

323. CAES 

324. Wave energy 

325. HTS power cables 

326. Smart Card 

327. Capacitor voltage transformer 

328. DVD Combo ROM disc Technology 

329. Microprocessor Based Motor Speed Controller 

330. Calorimetric measuring systems: Problems and solution 

331. Magnetic Levitation & it’s Application 

332. Magnetic material used in static rotating machines 

333. Global Positing System 

334. Pumped Hydroelectric Energy Storage 

335. Nomad Expert Technician System 

336. Kalpsar Project Capturing Tidal energy 

337. Flywheel Energy Storage System (FESS 

338. Protection of transmission systems by using the global positioning system 

339. Condition Monitoring of Electrical equipment 

340. CT Scanning 

341. Nanotechnology-The Next Science Frontier 

342. Conducting polymers & plastic batteries 

343. Modern Trends & Evolution of C B 

344. Matrix Inversion Generator 

345. Lates IE Rules 

346. Missile guidance system 

347. Magnetic Levitation 

348. Surge current protection using superconductors 

349. High Voltage Transmission Line 

350. Excitation System for Alternator & AVR 

351. Written-Pole technology 

352. Transient Over Voltages 

353. Instrument Landing System 

354. Project Oxygen 

355. Speech Enabled Interactive Voice Response System 

356. Grid Connected PV Systems 

357. Energy Conservation in Electrical equipment 

358. Cascade Tripping 

359. High voltage test techniques 

360. Micro-power Generator 

361. Magnetic Levitation And Its Application 

362. Demand side management and energy audit 

363. High Voltage D C Transmission 

364. High Voltage A C Transmission 

365. Iris Scanning 

366. Conditional Access (CA System) 

367. Magnox 

368. Battery Charger 

369. E-mail alert System 

370. Internet through power lines 

371. Biomass Fuelled Power Plant 

372. Wireless Application protocol 

373. Development of Superconducting Rotating Machines 

374. Radio Correction Finder 

375. Secure Authentication Using Automated Biometrics 

376. Quality of Electrical power 

377. Direct Methanol Fuel Cell 

378. Design of solar power plant 

379. Protection Against Blackout 

380. Power Quality 

381. Tidal power 

382. Intelligent Substation 

383. Electrical and chemical diagnostics of transformer insulation 

384. Relay performance & testing 

385. Introduction to Data Mining and Knowledge Discovery 

386. SF6 circuit breaker 

387. Paralleling of LTC transformer 

388. UPS 

389. Helms Pump Storage Plant 

390. Speech Synthesis 

391. Brushless Alternators 

392. Transmission for Offshore Wind Farms 

393. Energy Saving Fan 

394. AC Cable Versus shos Cable Transmission for Offshore Wind Farms 

395. Universal Current Sensor 

396. Controller Of Electric Vehicle 

397. Testing of transformers 

398. Fiber optical sensors 

399. ANN Based Power System Restoration 

400. V/F method of speed control 

401. Technique for Online Detection of Shorts in Fields 

402. Microprocessor based alternator synchronization 

403. Lighting protection of over head 

404. Microprocessor Based Protective Relays 

405. Different types of energy storage system 

406. PLCC 

407. PPTC Devices for Protection of Battery Packs 

408. Robotics and its Applications 

409. Micowave genration & its application 

410. Fusion Energy 

411. Variable Reluctance Motor Drive 

412. Satellite solar power station 

413. Navigation system 

414. Traction Drives 

415. Molecular Electronics 

416. Nano Technology 

417. Losses reduction system in power 

418. HVDC Technology and Short Circuit Contribution of HVDC Light? 

419. DSP For Motor Control 

420. Generator protection 

421. Mercury removal in coal burned power plants by electro catalytic oxidation 

422. 12 Phase Capacitor 

423. Transformers Internal Incipient Fault Model 

424. Numerical Relay 

425. Wave Power Devices 

426. Feeder Protective Relay 

427. Localization of faults 

428. Friction machines 

429. Microprocessor based X’mer Protection 

430. Effect of Under Frequency on Generating Units 

431. Data Acquisition System 

432. Linear Induction motor 

433. Static VAR (Voltage Ampere Reactive compensator) 

434. Electrowetting 

435. Fuel cell driven vehical 

436. Integration of IT in Machine Tools 

437. Robotics Sensor 

438. Production & protection against surges 

439. Opto Electric Battery 

440. High-availability power systems: Redundancy options 

441. Electro wetting 

442. Micro Power Electrostatic Generator (MEG 

443. Harmonic elimination techniques 

444. Growler 

445. Development & compensation of transm line 

446. Dual-Core Processor 

447. EHV AC Transmission 

448. Reactive power management 

449. Seasonal Influence on Safety of Substation Grounding 

450. Radial Feeder Protection 

451. Automatic voltage regulation of alternator used in UKAI PP 

452. Liquefied Natural G 

453. Train lighting on railways 

454. Compressed Air Energy Storage (CAES 

455. Latest trends in nuclear power station 

456. Energy transmission system for an artificial heart - leakage inductance compensation 

457. Automation of temperature rise test for switchgear 

458. Comparative Study Of Maximum Power Point Tracking 

459. EHV transmission system 

460. Iridium Satellite Phone 

461. Solid State Interlocking 

462. Electrocardiogram 

463. E-paper 

464. Bone growth using electrical simulation 

465. Internet telephony 

466. The global voltage regulation 

467. Magnox Nuclear Reactor 

468. Adaptive Piezoelectric energy harvesting circuit 

469. Review of Electricity Act -2003 

470. Vacuum Circuit Breaker 

471. ACSR & alloy 

472. Ocean Thermal Energy Conversion 

473. Optical current transducer & its fault location in substation 

474. Input Output Completion Ports 

475. Super conducting generator 

476. Motor Protection 

477. Numerical relays 

478. Power EC based distribution transformer 

479. User Authentication using Automated Biometrics 

480. Industrial fire safety 

481. Intrusion Detection With Snort 

482. Icing of Power Transmission lines 

483. Electronic Ballast 

484. Electronic Fuel Injection (EFI 

485. Tsunami Early Warning System 

486. E-Bomb 

487. Broadband Over Power Lines (BPL 

488. Condenser Bushing 

489. Wind Diesel systems 

490. Magneto hydrodynamic Power Generation Technology (MHD