Controller for 1kW-5kW wind-solar hybrid generation systems

In the districts where solar energy and wind energy are naturally complementary, the application of wind-solar hybrid generation systems (WSHGS) can reduce the storage capacity of batteries and the total cost of the system compared with stand-alone PV or wind generation system. This paper presents a cost-effect controller system for 1 kW to 5 kW WSHGS with low DC voltage input (24 V DC or 48 V DC) and high output AC sine wave voltage (220 V AC). This controller system includes features as follows: (1) PWM chopping technology in charging control of batteries, which can make wind turbine and solar array operate at maximum power point so that the overall system efficiency can be improved greatly. (2) Constant voltage and limited current two-loops control of battery charge, which can make batteries in float charging state, enhance the cycle rate and prolong the life of the batteries. (3) SPWM conversion with front-end high frequency DC-DC modules in parallel and special microchip control IC with high performance-cost, which can accomplish sine wave output voltage with high reliability and high load efficiency.