The compliance levels of control performance standard（CPS） are often improved at the expense of increasing the number of times of generator regulation instructions. If generators are regulated frequently， their coal consumption and wear and tear will significantly increase， which may result in lower production profitability. In order to reach a reasonable compromise between CPS compliance and the automatic generation control（AGC） regulation burden， and to enhance the system robustness， a novel variable universe fuzzy control based relax control method for AGC systems is proposed. With the introduction of the relax control logic into the fuzzy rules， the variable universe fuzzy controller can adaptively tune the gains of the PI controller of AGC systems. The simulation results show that even under the circumstances of system parameter changes or strong stochastic disturbances， the proposed controller not only ensures fast load adaptability， large stability margin and strong robustness， but also effectively reduces the number of times of regulation instructions and inverse regulations while satisfying the CPS compliance requirement.