Operation Analysis Of The Governor In Longshou Ⅱ Hydropower Station And Its Performance Optimization

Longshou II hydropower station is the seventh cascade hydropower station of the hydropower cascade planning for Heihe. BWT oil-free stepping governor system of the hydraulic turbine is used as the governor system of the power station. After nearly three years of operation, it gradually appeared that the synchronization time of the unit became longer, the stability of the regulation on the unit's guide vine got poor; the manual no-load frequency had a large fluctuation, the fluctuation of manual no-load frequency is between 0.3 Hz and 0.4 Hz, and the automatic no-load frequency is between 0.3 Hz and 0.6 Hz; the networking communications between the governor system and the computer monitoring system for Power Plant involve less data.; The starting current for the motor of governor's hydraulic device is large, which can usually lead to the adhesion of the contacts, and the working oil pressure can't be guaranteed in the normal range, thus the safety and reliability of systems is unable to be ensured, and all of those problems are seriously affecting security and reliability of the power station's operation.As the actual situation is that the stability of the governor running with no load is worse at Longshou II hydropower station, with the current regulation theory and technology of the turbine governor at home and abroad, an improvement of the governor is made. Firstly, improvement measure of PID control algorithm of the governor is proposed. A new compensated PID control algorithm is adopted in this paper; Secondly, by improving the communication procedures of the governor, and with increased communication data, so the management and operation carried by the operations personnel from the power plant can be satisfied; Thirdly, the oil supply units and the oil pump control system of the governor is also transformed, instead of the contactors, the intelligent soft-start device is used to start the pumps, the starting performance for the motor is improved, which make the reliability of the hydraulic device largely improved, so safe and stable operation of the governor will be ensured.After transformation, the static and dynamic characteristics tests are taken for the governor, the results shows that each of the performance indexes can be in line with the requirements in the GB9625.1-1997; On the premise that the stability of the system is ensured, the steady precision accuracy of the governor system, as well as rapidity of the control, is improved; The result of the actual operation, in various working conditions or under each kind of adjustment patterns, is proved to be very well.