Analysis on unit disconnection accident of 700MW unit caused by switchover failure of auxiliary power and preventive measures

Abstract

Abstract:

After the 700MW unit of a power plant had been connected into grid, the auxiliary power switchover had failed; due to the bus voltage loss, the 1A

stator cooling water pump was stopped; although the 1B stator cooling water pump started automatically, but the stator cooling water pressure difference low

signal had been given out, and protection device had tripped and caused the generator disconnection from the power system. The reason of the protection trip

was analyzed in depth; and the hidden dangers were found. Some prevent measures were proposed with 3 aspects of measures such as optimizing the interlock

protection logic, replacing the instruments by new type instruments and formulating antiaccident measures; and the safety hidden dangers for unit operation

were eliminated effectively. 

Key words: stator cooling water, disconnection, interlock control, auxiliary power

YIN Song. Analysis on unit disconnection accident of 700MW unit caused by switchover failure of auxiliary power and preventive measures[J]. Huadian Technology, 2012, 34(8): 44-46.

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Analysis on unit disconnection accident of 700MW unit caused by switchover failure of auxiliary power and preventive measures

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