Abstract: Load adjustment of power plants with the condensate throttling can reduce the throttle loss of governing stage and improve the operation economy and security, without the loss of response performance. This article identifies the condensate flow-load’s transfer function of certain 600 MW plant by analyzing condensate throttling dynamic model, and give out a fuzzy adaptive control algorithm, based on which the control system works well in field operation. The result shows that the max range of condensate throttling is about 800 t/h under secure conditions. The response time for load is 10 s, and the load amplitude of the response is 9 MW. Grid assessment indicators value KP increases about 10%, and efficiencies of HP increase 1.42%, 1.20% and 0.99% on load point 400, 450 and 500 MW, which decease average coal consumption by 1.77, 1.26, 0.91 g/(kW·h), indicating the economy benefits and improvement in load control of condensate throttling.

Key words: power unit, load regulation, AGC response rate, condensate throttling, energy saving, control algorithm