不同类型风电场对现有继电保护仿真对比分析

The simulation and comparative analysis of the different types of wind farms on the existing protection relay

不同类型风电场接入电网系统表现出异于常规电源的故障特征,使得基于常规电源的继电保护应用存在适应性问题。针对不同类型风电场的故障特征,仿真分析风电场送出线路在不同故障、不同运行工况下各种继电保护元件(差动元件、方向元件、距离元件及选相元件等)的动作性能。分析结果表明,双馈风电场出现送出线路发生故障时系统表现出弱馈性和频偏性,对基于工频向量的保护元件产生严重影响;直驱风电场送出线路故障只对负序、零序方向元件及选相元件产生部分影响。

The different types of wind farms connecting to grid system shows unique fault features which are different from traditional power supply. There exists an adaptability problem for the application of protection relays based on traditional power supply. According to the fault characteristics of the different types of wind farms, the operation per- formance of different faults and different operating conditions （ the differential element, the directional element, the distance element and the phase-selection element） is simulated and analyzed. The analysis results show that, when the fault current of DFIG wind farm outgoing transmission appears, the wind power system, the frequency of that will deviate~, shows poor feedback, which has vicious impact on the protective device based on frequency vector; However, the direct drive wind farm only has partial influence on the negative sequence, zero sequence direction dement, the phase-selection： element.