伪直流链逆变技术在光伏逆变器中的应用

Application of Pseudo DC-Link Inverter Technology in PV Inverter

提出一种新型光伏逆变器,采用伪直流链逆变技术,将传统逆变技术与软开关技术相结合,使逆变器前级直接输出工频全波整流电压,后级只需进行电压极性翻转。加上倍压整流电路的引入,使其与传统光伏逆变器相比,具有升压比大、效率高、体积小、滤波效果好等优点。对该逆变器运行机理和工作模态进行了分析,通过实验证明了该方案的可行性,给出了实验相关波形和不同负载下的工作效率。

Combined with the traditional inverter technology and the soft-switch technology,a new type of pho- tovoltaic （PV） inverter which used the pseudo DC-link inverter technology was proposed. The former inverter directly output power frequency full-wave rectified voltage and the latter inverter achieved the flip of voltage polarity. After the introduction of double voltage rectification circuit,compared with traditional PV inverter,it had the advantages such as large step-up ratio,high efficiency,small size and good filtering,etc. The operation principle and operation mode were analyzed. Experiments were performed to verify the theoretical analysis,as well as the waveforms and efficiency of different loads were given.