应用边界保护原理提高分布式发电系统并网协调性的方法

An Approach to Improve Interconnection Coordination of Distributed Power Generation System by Boundary Protection Principle

为解决分布式发电系统与配电网保护的协调性问题,提出了一种新的分布式发电(distributed generation,DG)并网控制方法。由于在DG系统并网点上游和下游线路故障时,DG系统对电网保护的影响是不同的,因此提出在带有DG系统的配电线路上装设阻波器构成线路边界的思想,采用行波边界保护模式,对DG系统并网点上游和下游故障进行选择性保护,进而保证配电线路故障后DG系统能够快速准确地解列,确保系统的安全运行,并最大限度地提高DG的利用效率。仿真结果和理论分析表明,新保护方法可提高DG与配电网的协调性,并可有效提高DG的利用效率。

To coordinate of distributed power generation system with the protection of distribution network, a new interconnection control approach for distributed generation （DG） is proposed. Because of the different influence of DG on distribution network protection under the fault occurred in upper or lower lines opposite to the interconnection point of DG, for this reason it is put forward to install wave trappers in distribution network containing DG to form line boundaries, and by means of traveling wave boundary protection mode the selective protection is implemented for the faults occurred in upper or lower lines opposite to the interconnection point of DG to ensure that the DG can be disconnected quickly and accurately after distribution lines is in fault and the secure operation of distribution network as well as to improve the utilization efficiency of DG furthest. Results of simulation and theoretical analysis show that the proposed new protection mode can improve the coordination of DG with distribution network and the utilization efficiency of DG availably.