Dual feedback linearization control based on direct power control (DPC) for three-phase pulse-width-modulation (PWM) voltage-source rectifier (VSR), which connects to grid voltage during network unbalance, is proposed. And there is a non-linear PI controller as the system's outer loop controller, which can accelerate the response of DC voltage in the case of load changing. The positive sequence and negative sequence instantaneous power models of the PWM rectifier are respectively established. The positive sequence active power and reactive power are entirely produced by positive sequence voltages and positive sequence currents. And the negative sequence active power and reactive power are entirely produced by negative sequence voltages and negative sequence currents. The dual power control scheme with feedback linearization control is presented. The positive sequence instantaneous power and the negative sequence instantaneous power achieve decoupling control. By changing reference, the proposed strategy can achieve different control objectives such as: eliminating active and reactive power oscillation without sinusoidal line current, eliminating active power oscillation with sinusoidal line current, eliminating reactive power oscillation with sinusoidal line current or eliminating negative sequence current. Test results show the good performance of the proposed strategy.
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