单相光伏逆变器的改进型孤岛检测方法

Improved Islanding Effect Detect Method of Single-Phase Photovoltaic Inverters

分析光伏逆变器在并网时的安全保护问题,详细分析了孤岛效应检测的基本原理,提出了一种主动式移相孤岛检测和过/欠压/频的被动式孤岛检测相结合的反孤岛效应方案,使用DSP进行数字控制实现逆变器的孤岛检测,完成了孤岛硬件保护电路和DSP软件设计,实验结果表明,该孤岛检测方案快速可靠,检测所需时间远小于国际标准所规定的最大检测时间,检测盲区非常小,确保系统安全和高效运行.

Analysis is given of grid PV inverters in the safety protection, as well principle of islanding detection method analyzed in detail, a combined scheme is proposed of the over/under-voltage, over/under- frequency of the passive form islanding detection and the phase shifting one, using DSP as numerical control leading to the big simplification of realizing the inverter islanding detection, which is completed on DSP control including the island protect electric circuit and software design, experimental results show that rapid, reliable islanding detection scheme in this dissertation brings out the maximum detection time required being far less than the international standards, the Non-detection Zone is very small, ensure system under an safe and efficient operation.