A grid-connected control method based on a virtual resistor with a current source type PWM rectifier. A grid-connected rectifier consists of a commercial power (5), an alternating-current filtering inductor (4), an alternating-current filtering capacitor (2), a three-phase current source type rectifying bridge (1), a direct-current inductor (6), a direct-current capacitor (8) and a digital controller. The sampled voltage of the alternating-current filtering capacitor is transmitted to a microprocessor (11) to perform digital phase locking, and after phase locking is finished, the voltage and the phase of the alternating-current filtering capacitor are transmitted to an alternating-current current controller (15). The alternating-current current controller consists of a coordinate converter (18), a virtual resistor regulator of d axis (19), a virtual resistor regulator of q axis (20) and a divider (21). The coordinate converter converts the three-phase voltage of the alternating-current filtering capacitor into the voltage under a two-phase static coordinate system, after the voltage is regulated by the virtual resistor regulator, the current passing through the virtual resistor is obtained, the control amount of the alternating-current side is obtained through the divider, the control amount is superposed on the control amount of the direct-current side, a driving signal obtained through a PWM generator (17) is transmitted to a driving board (12), and after the signal is amplified by the driving board, the connection and disconnection of the switches of the three-phase current source type rectifying bridge are controlled. Through digital control arithmetic, the rectifier is equivalent to that a resistor is directly connected with the alternating-current side capacitor in parallel, so that the resonance of the inductor and the capacitor at the alternating-current side can be effectively restrained, the total harmonic distortion in grid-connected current can be reduced, and the stability and the dynamic response characteristic of the direct-current side can not be influenced.
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