The invention discloses a direct
power control method for current negative sequence component restraining under network unbalance. The direct
power control method comprises the steps that three-phase
voltage and three-phase current of a
transformer are detected and transformed into a two-phase static coordinate
system, T / 4
delay positive-negative sequence
decomposition is carried out on two-phase static
voltage and two-phase static current, active power and reactive power of a
system are calculated, and the active power and the reactive power are predicted; compensation power in the two-phase static coordinate
system is calculated when negative-sequence current needs to be zero, the negative-sequence current is made to be zero, and given active power and reactive power of the system are calculated; a conditional function is set up, an SVPWM positive-sequence
voltage component is solved, an SVPWM negative-sequence
voltage vector is determined, and an SVPWM
voltage vector is output to a
PWM rectifier. The direct
power control method has the advantages that during a network unbalance fault, it can be guaranteed that the system is stable, response speed is high, design of a
power filter is facilitated, the requirement for system sampling frequency is not high, and high robustness and good adaptability are achieved.