Causal Analysis of Leading-phase-operation-induced Activation of Generator Protection Against Loss of Excitation
The test of leading-phaseoperation examines generators'tolerance to system voltage reduction when they are needed to absorb reactive power.Protection against loss of excitation protection is a mechanism to island and protect the generator whenexcitationcurrent disappears.However,during the process ofleading-phase operation,excitation current and excitation voltage will decrease,and the measured impedance at generator end may fall into demagnetizing imped-ancecircle,thereby activating the protection.This paper reports an activation of protection against loss of excitation en-countered byan actualplant duringleading-phase operation.It analyzes comprehensively protectionrecords,protective threshold for loss of excitation,logic diagram of protection mechanism,excitation regulator,and the process of leading-phase operation,and puts forward specific treatment measures and suggestions.
leading-phase operationprotection against loss of excitationdemagnetizing impedance circle
万方数据
维普
