摘要
以大面积采用微机保护装置的三峡水电厂复杂厂用电系统为研究对象,针对其运行方式分析困难等复杂问题,结合电厂的实际运行工况,提出以厂用电母线为主要研究节点,确定母线的最大(小)运行方式,以其最大运行方式下发生三相短路电流值来整定,最小运行方式下发生两相短路电流值来校验,解决复杂系统整定值配合问题。并在分析了该厂保护固有动作时间及保护装置特性的基础上,采取缩短时间级差的方法来确保主保护的速动性,有效解决复杂厂用电系统多级保护之间保护动作时间的配合问题。结果表明,水电厂投入运行以来没有出现因时间级差缩短到0.2s而造成保护的误动。
The large area of microcomputer protections for complex auxiliary power supply（CAPS） of Three-Gorge power station is taken as an example.According to its difficult analysis of operation modes and associated with the practical operation situation in the power station,the bus of auxiliary power supply is chosen as the main study node in order to determine the maximum and minimum operation mode of the bus.Then,the value of three phase short-circuit current under the maximum operating mode is used as the setting value and the value of two phase short-circuit current under the minimum operating one is used to check.Both values are used to solve the problem of setting coordination for the complex system.What＇s more,base on the analysis of the fixed actuation time and the characteristic of protection devices,reducing the time step difference is adopted to ensure high speed of main protection,which can effectively solve coordination of protection actuation time for the multi-grade protection of CAPS.The result shows that after time step difference reduced to 0.2s,no malfunction of protection happens since the station puts into operation.
出处
《水电自动化与大坝监测》
2011年第6期34-37,共4页
HYDROPOWER AUTOMATION AND DAM MONITORING
