Abstract: In recent years,with the rapid development of new energy in China,there is an urgent need for coal-fired power to enhance its fundamental role in support and regulation. As coal-fired power units will face tests of flexible operation capabilities,frequent peak shaving and start-stop peak shaving will become the norm. Coal-fired power units will widely participate in the deep peak shaving of the power grid,while the long-term operation of the units deviating from the design conditions will bring hidden dangers to safety production. This article takes a 300 MW wet cooled pure condensing coal-fired power unit as an example to deeply analyze the impact of the power grid auxiliary service mechanism on the safe operation of coal-fired power units and effective countermeasures,which has reference significance for the majority of coal-fired power units participating in auxiliary services.

Key words: power grid, coal-fired power unit, auxiliary service