基于负序量排序及5G通信的主动配电网有界面保护原理

The principle of bounded area-protection for an active distribution network based on negative sequence quantity sorting and 5G communication

针对大量分布式电源(distributed generation, DG)接入配电网对传统保护带来的新挑战,提出了一种基于负序量排序与5G通信相结合的配电网有界面保护原理。为实现保护范围的有界及灵活配置,并应对极端工况下的主判据失效问题,设计了一种免整定的实测-补偿电压幅值比较判据。在信息交互方面,结合配电网通信特点,提出了带时标的5G通信方式,进一步降低了所提保护对同步通信的要求。仿真结果表明,对于带不可测分支的线路,所提判据均可成功应用,并且不依赖于数据同步通信。相较于传统三段式电流保护,保护新方案能够大大提升配电网的故障切除速度,保证故障极限响应时间均在90 ms以内。在数十欧姆的相间弧光过渡电阻和接地电阻的情形下,该方案仍能具有良好的故障辨识能力。相比于幅值差动保护,所提保护具有对不可测分支更强的适应性和动作稳定性。

There are emerging challenges posed by the integration of a large number of distributed generations(DGs)into power distribution networks.Thus this paper proposes a novel bounded area-protection that combines negative-sequence quantity sorting with 5G communication.To achieve a bounded protection range with flexible configuration and address the issue of main criterion failure in extreme conditions,it introduces a measurement-compensated voltage magnitude comparison criterion that eliminates the need for re-adjustment.For information exchange,a 5G communication method with timestamps is proposed,further reducing the synchronous communication requirements of the proposed protection scheme by leveraging the communication characteristics of distribution networks.Simulation results demonstrate the successful application of the proposed criteria to lines with unpredictable branches without relying on data synchronization communication.Compared to traditional three-section current protection,the new protection scheme significantly enhances fault clearance speed,ensuring that the fault’s maximum response time remains within 90 ms.Even under conditions involving tens of ohms of inter-phase arc transition resistance and ground resistance,the proposed scheme maintains excellent fault identification capability.In comparison to amplitude differential protection,the proposed protection exhibits stronger adaptability and operational stability against unpredictable branches.