Hybrid Solar Wind Charger

The commonly used Uninterrupted Power Supply systems take its power directly from the supply mains and consumes much higher energy for its functioning. Considering the energy availability crisis and higher living cost, it is necessary to find an alternative power source for such a system. Here, we propose a system to design a UPS which will utilize the everlasting solar and wind power, thereby checking the energy crisis to a certain limit and is termed as “HYBRID CHARGER”.

Since hybrid systems include both solar and wind power, they allow the power user to benefit from the advantages provided of both forms of energy. Obviously, solar panels don’t provide power during the night, but that’s when the wind usually picks up and conversely, on the longest, hottest days of days of summer, the wind often doesn’t blow, but the sun is at its strongest great for solar power. The wind is more likely to blow during the cold, short days of winter when the sun is at its weakest. A purely solar power solution for general lighting load is very expensive as far as initial investment is concerned. Also, due to frequent power failure, a regular battery backup UPS/INVERTER barely gets time to charge the battery from mains. The hybrid version combines solar energy, wind energy and mains utility to give an excellent solution by providing the best of both worlds. While proposing this project of designing a hybrid charger, the following data must be taken into account.

Although fossil fuels have led us to economic prosperity, the extensive use has caused a substantial reduction of fossil fuels. Therefore, the solar energy, as one of the green energy resources, has become an important alternative for the future. It can be considered to use the parallel loaded resonant converter with the feature of the soft switching technique in the circuits of the solar storage battery charger. To avoid the damage of the battery charger due to the variation of the output current of the solar PV panels, a closed-loop boost converter between the solar PV panel and the battery charger was designed to stabilize the output current of the solar PV panel. By designing the characteristic impedance of the resonant tank, the charging current of the storage battery can be calculated and then the charging time for the storage battery can further be estimated. 

By properly designing the circuit parameters, the parallel loaded resonant converter can be operated in the continuous current conduction mode and the switch can be switched for conduction at zero voltage. Such experimental results verified the correctness of the theoretic estimation for the proposed battery charger circuit. The average charging efficiency of the battery charger can be up to 88.7%.