基于RTDS的光伏接入配电网故障特征研究

随着光伏在配电网渗透率的不断提高,光伏电源故障特征的研究对于配电网的保护控制尤为重要。通过建立光伏并网系统的暂态模型,研究了分布式光伏电源的暂态特性并给出了其电磁暂态全电流方程。利用实际光伏并网控制器,搭建了基于RTDS仿真平台的实时混合仿真系统,通过该系统验证了具有低电压穿越能力的单极式光伏在不同故障情况下的暂态全过程,分析了不对称故障下分布式光伏电源低电压穿越期间的谐波特性。通过理论分析和实验验证全面阐述了光伏电源的故障特征,为光伏接入配电网的故障电流计算及保护整定提供了参考依据。

Research on fault characteristics of distributed photovoltaic system in distributed network based on RTDS

With the increasing penetration of photovoltaic in distribution network, the research on the fault characteristics of photovoltaic is particularly important for the protection and control of distribution network. By establishing the transient model of distributed photovoltaic generator, the power characteristics of distributed photovoltaic generator under the fault condition are analyzed and the equation of electromagnetic transient current is given. A control-in-the-loop simulation system based on an actual photovoltaic controller is built on the RTDS simulation platform. Through this platform, it verifies the transient process of the unipolar photovoltaic generator with low voltage ride through capability in different fault conditions. The current harmonic characteristics of the distributed photovoltaic generator are also analyzed under asymmetric faults. The fault characteristics of photovoltaic are comprehensively expounded through theoretical analysis and experimental verification, which provides a reference for the calculation of fault current and the protection setting of photovoltaic access to distribution network. This work is supported by National Key Research and Development Program of China (No. 2017YFB0902900) and Science and Technology Project of State Grid Anhui Electric Power Co., Ltd. (No. 52120017001G).