Research On Inverter For Independent Solar Energy System

In recent years, photovoltaic power technology has widespread application, along with our country new energy law enacted. Photovoltaic power system will have broader development space in our county. The inverter supply is highly concerned as one of crucial parts functioned in the PV system. The fundamental function of the inverter supply is designed to transform DC from solar or battery module into AC for the requisitions of loads.Therefore, an inverter by using the"push-pull circuit+high frequency trnasformer+single phase full bridge inverter"design proposal is developed, which help to reduce system volume and increase system efficiency. The entire system consists of hardware and software designed, hardware divides into DC-DC part and DC-AC part. In DC-DC design part, this article uses the voltage feedback and current feedback, avoids the high-frequency transformer magnetic bias saturated question, at the same time increases the system stability and the dynamic speed of response. The controller is UC3846 current mode control chip. This paper also discusses the high-frequency transformer design, the filter components parameters choices in detail. In DC-AC design part the Integrated Power Module is used, which can simplify the drive circuit design. The system antijmaming ability is increased because IPM has under-voltgae protection and short circuit protection built-in. The control chip is inexpensive, superior peorfmrnace 51 series controller AT89C51, combining with single-phase SPWM producer and A/D convertor ADC0809 produces theSPWM wave and monitors system condition. In the aspect of software design, the calculation of controlling amplitude modulation value is fulfilled with the PI control algorithm. Specifically, the on/off shifting time of regulating switch is manipulated associated with the requirement of output voltage stabilization at 220V.Finally, the debug process and researching results are systematically presented and the feasibility of invert strategy is successfully verified as well. Hence, it is proved that the cost of photovoltaic power generation is reduced significantly; furthermore, the reliability is reinforced by the scientifically designed circuits and structures.