广东电网两起稳定破坏事故的分析

Analysis of Two Stability Disruption Accidents in Guangdong Power Grid

针对目前我国电力网稳定破坏事故中,围绕负荷中心的地区电网事故明显增多的现象,详细介绍和分析了广东电网两起典型的电网稳定破坏事故——1994年"5.25"粤东电网大面积停电事故和1995年"12.15"粤北电网崩溃事故。这两起事故发生的诱因均是输送界面的1条220kV输电线路因热稳定受破坏而断电,造成事故扩大的主要原因是广东主网对局部电网界面输送的潮流超过了暂态稳定极限,导致事故电网异步振荡。结合目前广东电网运行中存在的薄弱环节,提出建议:要严格执行各项规程、导则和管理条例;在电力、电量紧缺和事故处理期间,应加强各级调度的力度;完善安全稳定自动装置的各级功能;当电网结构变化时,应及时修改并下达各运行参数和继电保护装置整定值;加强安全自动装置在各种约束条件下运行策略的研究和调度员的专业培训。

In view of the notable increase of regional power grid accidents around load centers in stability disrupting accidents in Chinese power grid at present, this paper detailedly introduces and analyzes two typical accidents that disrupted the stability of Guangdong power grid. i.e. , the May 25 large-scope blackout in east Guangdong power grid in 1994 and the December 15 collapse in north Guangdong power grid in 1995. Both the accidents were induced by the power supply interruption of a 220 kV transmission line as a result of impaired thermal stability, and extended mainly due to the load flow from the main network to local network that exceeded the transient stability limit and led to asynchronous oscillation of the faulty power network. In combination with the weak links existing in operation of Guangdong power grid, some suggestions are brought forward, which include strictly carrying out various codes, guiding criteria and regulations, strengthening dispatching at all levels in periods of power shortage and fault handling, improving the function of automatic safety devices, opportunely amending and sending the setting values of operation parameters and protective relays in case of changes in power grid structure, intensifying research on operation strategies of automatic safety devices under different restrictive conditions as well as professional training of dispatchers.