Study on Relay Protection Scheme in Wind Power Integration Distribute Network

Abstract

现有的继电保护系统中一般将风力发电系统作为同步发电机处理，不考虑故障下风电场提供的短路电流对继电保护的影响，但是随着大规模风电接入配电网，风力发电系统对配电网故障点提供的短路电流将会降低继电保护装置的选择性，进而导致继电保护装置的误动。为了保证继电保护满足“四性”的要求，本文通过研究分析风电接入配电网下的故障机理，提出将具有动作速度快、方向性明确、不受过渡阻抗影响的工频故障分量距离保护应用于配网的保护方案中。 Wind power generation system is generally treated as synchronous generators in the relay pro-tection system, and regardless of influence short-circuit current that provided by wind farms. But with large-scale wind power integration distribute network, the selectivity of relay protection devices is reduced by short circuit current provided by wind power generation system, which leads to the maloperation of relay protection device. In order to guarantee the relay protection to meet the requirements of the “four characteristics”, this paper, through research and analysis on wind power distribution network fault mechanism, puts forward that distance protection using power frequency fault components of voltage and current which has action speed, clear direction and not affected by the influence of transition impedance is applied to distribution network protection scheme.