基于农村小功率微网的光伏电压转换模式研究

Research on Photovoltaic Voltage Conversion Mode Based on Rural Low Power Microgrid

太阳能作为绿色可再生能源已广泛应用光伏电站,但农村应用并不是很广泛。尤其是西部农村地区地广人稀,并且光照强度大、日照时间长,应该进一步推广。针对光伏电压等级与用户设备的不同等问题,对光伏电池的DC电压转换为可应用的AC电压转换模式进行了研究。通常有工频变压器隔离变换型(DC/AC+AC/AC)、非隔离式变换型(DC/DC+DC/AC)两种电压转换模式。分别给出了两种模式的电路分析,并对其进行了仿真研究,通过对输出电压波形、输出功率波形和系统鲁棒性验证。验证得出DC/AC+AC/AC电压转换模式具有更好经济性和稳定性。

Solar energy has been widely used as a green renewable energy source,but rural applications are not very extensive.In particular,the rural areas in the west are sparsely populated,and the area has large light intensity and long sunshine hours,which should be further promoted due to the difference in photovoltaic voltage levels and user equipment.In this paper,the DC voltage conversion of photovoltaic cells into applicable AC voltage conversion modes was studied.There are usually two types of voltage conversion modes:power frequency transformer isolation conversion type(DC/AC+AC/AC)and non-isolated conversion type(DC/DC+DC/AC).The circuit analyses of the two modes were given respectively,and the simulation research was carried out to verify the output voltage waveform,and output power waveform and system robustness.It is verified that the DC/AC+AC/AC voltage conversion mode is more economical and stable.