光伏电站接入配电网后，在改变电网原有拓扑结构和潮流方向的同时，其电能输出特性直接影响到电网的电能质量。为保障现有电网的安全稳定，更好利用太阳能，在光伏电站接入系统前的设计阶段需对光伏发电接入系统进行电能质量评估。结合实际工程案例，以某MW级分布式光伏电站为研究对象，根据分布式光伏电站接入电网时的电能质量要求，基于Matlab/Simulink仿真平台进行建模，对并网电能质量进行评估计算，并进行相应的分析。计算结果表明：该分布式光伏电站接入点符合电能质量要求，允许接入系统。

When the photovoltaic power station is connected to the utility grid, the adverse impact was made on many aspects due to the inherent characteristics and the change of grid structure and power flow, such as power quality, planning operation and relay protection. For better use of solar energy and less effect on power energy quality of the system, making power quality testing and evaluation are needed in the design period before the photovoltaic substation connected into power system. In this paper, the power quality requirements of a practical distributed PV power station are summarized. The numerical model of grid-connected photovoltaic power station is built based on the Matlab/Simulink platform, and the power quality testing and evaluation of the photovoltaic substation connecting into power system are made. The results show that the power quality demands of the connecting points of the photovoltaic substation are satisfied, and the photovoltaic power station is allowed to connect into the power system.