Is the steam source switching of the small turbine in Harbin Power internal or external?
1 Answers
The steam source switching method of the small turbine in Harbin Power is external switching. Small turbine steam source: The working steam source comes from the fourth extraction of the main unit, and the standby steam source comes from the cold reheat. The switching of steam sources is automatically controlled by the regulator. The steam source for debugging and startup comes from auxiliary steam, with a pressure of 0.98Mpa and a temperature of 300°C. The exhaust steam of the small turbine goes to the low-pressure condenser and the high-pressure condenser, with an exhaust pressure of 0.0069Mpa. Switching method: When the main unit load is below 40% of the rated load, the flow of low-pressure working steam can no longer meet the power requirements of the feedwater pump. At this time, under the coordination of the control system, the regulating valve on the auxiliary steam pipeline is opened to introduce auxiliary steam to supplement the work and maintain power balance. At this stage, all eight low-pressure regulating valves must remain fully open.