Effects of PV Power Station on Distance Protection and Automatic Reclosing
Guo Jinxue1, Nan Dongliang2, Hao Hongyan3, Zhang Feng3, Zhang Yi1
1. NR Electric Co., Ltd, Nanjing 211102; 2. State Grid Electric Power Research Institute of Xinjiang Electric Power Company, Urumqi 830011; 3. Xinjiang Electric Power Dispatching and Communication Center, Urumqi 830011
Abstract:The basic principle of distance protection is analyzed firstly. And the effect on transmission line, distance protection in distribution networks and automatic reclosing by PV power station are discussed. Based on the fault characteristics of PV power station and in the premise of convenient project application with allowable error, a model of PV power station short circuit is presented. The model is in voltage source impedance in series form. The fault characteristics of PV power station with different calculation formula of two different sequence impedance is given. The calculation model is added to the conventional grid short-circuit current calculation model. The short circuit current of power system with photovoltaic power station calculating is completed in the model. Based on the segment impedance sets setting of distance, the setting of current starting threshold value, the simulation model is set up. The influence of large-scale photovoltaic access on the short circuit level of regional power grid is studied. The protection starting of transmission lines with different positions and different types of fault phase current is verified. Also the distance protection starting with different positions and different types of faults is verified. Finally, some suggestions are given for the distance protection configuration, reclosing configuration and phase selection element of the grid connected photovoltaic system.