Abstract: In order to meet the needs of the power gridsecond FM regional,power unit to receive the AGC instruction will follow the grid frequency changes frequently,the magnitude and direction of change has very strong randomness,many thermal power units have electric load response time and adjust the rate exceed the standard problem of insufficient in AGC mode. Based on the analysis of the operation characteristics of the regional power grid AGC,the paper points out the main points of the AGC control scheme,and puts forward the variable load feedforward control strategy with adaptive ability. After several times of static test and dynamic simulation of variable load test,the control strategy is successfully applied to the CPI Anhui Pingwei Power Plant 2×1050MW ultra supercritical thermal power units,the practice proves that the AGC control strategy has strong adaptive capacity,improve the thermal power unit load response ability.

Key words: AGC, randomness, magnitude, direction, adaptive, coal feed-forward