Voltage Source PWM rectifier is a nonlinear, multivariable, strong coupling system, and it is sensitive to external disturbances and to perturbations in system parameters. Traditional direct power control strategy in PWM rectifier is of the advantages of high power factor, low harmonics of AC side and the strategy is simple, but when there is a disturbance or perturbation, the control effect is not ideal. To solve the problem, the paper designs a first-order active disturbance rejection controller(ADRC) to improve the traditional control strategy, including the arrangement of the transitional process, integrating the external disturbances and perturbations in system parameters as a total disturbances by using the extended state observer(ESO), then using nonlinear feedback control method to control rectifier. Finally, the simulation results show that when a disturbance or perturbation occurs, the improving control strategy has stronger robustness than the traditional control strategy, and the control results are satisfactory.