分布式发电孤岛检测的研究

针对光伏并网系统中孤岛效应的产生机理,提出了一种基于主动频率偏移扰动逆变器调制波的反孤岛检测法,该方法只需通过检测负载端电压频率变化就可快速地判断出系统是否发生孤岛。然后根据光伏并网原理,对其进行了建模和仿真研究。结果表明,本文提出的控制方法能实现网侧电流正弦化,且在满足时限条件下能快速准确地判断出系统的运行状态,验证了该方案的正确性。

Detection of distributed generation islanding

According to islanding effect on the grid-connected photovoltaic system,the paper puts forward an antiislanding method based on active frequency drift by perturb pulse modulation wave of the inverter. This method can detect islanding-effect quickly by real-time measuring load voltage. Then constructing model and research simulation were conducted according to the principle of grid-connected photovoltaic system. The result showed that the output current wave can keep same frequency and phase with the grid voltage as well as the method can estimate the operating states of system fast within limit time.