A combined cycle unit lubricating oil pump switch cause tripping event analysis and processing unit

A combined cycle unit lubricating oil pump switch cause tripping event analysis and deal with 2019 - unit 05 - 28 1 introduction two units of 390 mw unit S09FA combined cycle unit, for GE company MS900FA type gas turbine, the D10 type turbine, the 390 h generators, using Mark Ⅵ control system. 2 event description since put into production in 2005, a total of 3 times for two units of communication for steam turbine lubricating oil pump failure, the standby pump automatic rev, low lubricating oil pressure tripping events. In one, for example, a communication after lubricating oil pump failure, from the first low pressure measuring point alarm to trigger the lubricating oil pressure low tripping protection action, a total of 152 ms. From the low pressure lubrication after tripping alarm to prepare pump start-up pressure alarm reset to zero. 28s。 , according to check the unit trip because the lubricating oil pump fault shutdown to standby pump start-up period, there is a decrease in the lubricating oil pressure will process, Mark Ⅵ control system controller logic processing cycles of 40 ms, to capture the moment of the oil pressure signal changes, a unit tripping commands. 3 treatment measures 1: low oil pressure protection signal increase 2 s delay. The test results show that the ac lubricating oil pump after failover, lubricating oil pressure can be restored within 2 s. The following is a test process curve. Measure 2: mother in front of the lubricating oil pressure regulating valve tube mounted on three pressure transmitter, used to judge the communication happened when units lubricating oil pump switch, the standby pump start failure and dc oil pump start running condition. In this case, the unit to perform automatic shutdown procedure. Usually, only dc oil pump run-time lubricating oil pressure than the exchange of lubricating oil pump run-time lube oil pressure is low, add the three pressure transmitter is used to judge the only dc oil pump running status, Mark Ⅵ delay trigger unit automatically shut down the signal control system. According to the test results, add the following logic: dc lubricating oil pump pressure is less than 483 kpa, three choose two delay after 15 s, implement automatic stop procedures. 4 treatment effect after implementation of the above, some day in the factory in the operation of the unit 1 again in ac lubricating oil pump failure, the standby pump automatic Posting, successfully avoid tripping by lubricating oil pressure unit. 5 the author view ( 1) Similar event happens, the plant provides feasible effective measures, domestic steam turbine unit of main oil pump can draw lessons from the practice, but the fixed value should be obtained through field test. （ 2) The unit strictly implement the eight new counter measures 25 items. 4. Article 6: 'low oil alarm, lian kai pump, tripping protection, setting values should satisfy dc oil pump coupling and at the same time must be tripping down'. The dc lubricating oil pump operation after 15 s, the implementation of automatic stop practice, is worth using for reference. Note: this article case source gas turbine power generation technology, 2017, single shaft combined cycle sets of S109FA communication lubricating oil pump fault tripping unit processing, author: Cao Xiaohui.