Power distribution network reliability evaluation method considering switch control failure

Abstract

The invention provides a power distribution network reliability evaluation method considering switch control failure. The method comprises the following steps: finding out all possible power supply paths for each load point of a power distribution network; finding out all possible power supply paths for all elements of the power distribution network; selecting a fault element, traversing all load points, for each load point, determining all switches capable of isolating faults according to power supply path positions of the fault element and different load points, taking the switches as a fault isolation switch set of the load point, and calculating the probability that all the switches in the set are in a control failure state; calculating the probability that all switches in the fault area trip correctly to describe the reliability influence of the fault area, and then calculating the equivalent fault rate and equivalent fault time of the fault element to the load point; and traversing all fault elements, and counting equivalent fault rates and equivalent fault time of all fault elements to the load point, thereby obtaining power supply reliability indexes of the load and the system.

Description

technical field [0001] The invention relates to the field of distribution network reliability evaluation, and relates to a distribution network reliability evaluation method considering switch control failure. Background technique [0002] As communication technology, computer technology and control technology are widely used in the power system, the normal operation of the power system is inseparable from the monitoring and control of the secondary system. The increasingly obvious dependence of the power grid on the secondary system also makes the failure of switch control a potential factor affecting the safe and reliable operation of the distribution network. Therefore, the power supply reliability of the distribution network needs to fully consider the scenario of switch control failure. [0003] When a fault occurs in the distribution network, the feeder automation function of the secondary system isolates the faulty component by controlling the tripping of the switch, ...

AI Technical Summary

Problems solved by technology

However, when the switch control function fails, that is, when the switch that needs to isolate the faulty component refuses to operate, its adjacent switch will trip and replace the rejecting switch to isolate the fault, causing the power failure area to expand from the original faulty area to the non-faulty area. It is impossible to accurately determine the location of the faulty component, which not only leads to false power outages in non-faulty areas, but also prolongs the power outage time of the original faulty area, affecting the power supply reliability of the distribution network

[0004] Most of the existing studies on the reliability of distribution network considering the failure of switches in the fault handling process are based on specific automation modes, such as centralized feeder automation mode, and the complex timing modeling of the secondary system is not directly applicable. Other automation modes in engineering practice (Liu Wenxia, ​​Gong Qi, Guo Jing, Shan Xiaodong, Wang Zhiqiang. Reliability evaluation of active power distribution cyber-physical system based on hybrid communication network[J]. Chinese Journal of Electrical Engineering, 2018, 38( 06):1706-1718+1907.) (Deng Liangchen, Liu Yanli, Yu Yixin, Bai Tianyuan. Reliability Evaluation of Distribution Network Cyber-Physical System Considering the Whole Process of Fault Handling[J]. Electric Power Automation Equipment, 2017,37(12 ):22-29.), and most reliability evaluations are based on the Monte Carlo method, which has problems such as time-consuming and difficult to guarantee sampling accuracy in large-scale power distribution systems

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