An Alternative Current-Error Based Control for VSC Integration to Weak Grid

An enhanced current control strategy is proposed for voltage source converters for the integration to weak grids. The control derives from the current-error based vector control. By implementing simple close-loop compensations of both angle and magnitude inputs to the pulse width modulation, the damping of vector control in the weak grid can be significantly improved hence able to deliver full rated power to very weak grid. Due to the presence of the current loop, the fault-ride-through capability can be maintained with no need for mode switching. A comprehensive frequency domain model is employed to analyze the stability. Time domain simulations are further carried out to validate its effectiveness and robustness of integrating to the weak grid with fault-ride-through capability.