摘要
As a single current feedback method,the WAC(Weighted-Average Control) strategy achieves low distortion of the current with less steady-state error,and it also avoids the capacitance design problems that exist in traditional method based on splitting-capacitor.But the WAC strategy is limited to the interference from grid and an neglected resonant frequency.In this paper,an active damping method is used to improve the grid-connected current quality and restrain the resonance of system while degrading the control system.In addition,a grid voltage feed-forward control strategy is proposed to resist the grid disturbance which can not only change the control transfer function,but also have a negative effect on active damping method.Effectiveness and feasibility of the proposed strategy are verified by the simulation results.
As a single current feedback method,the WAC(Weighted-Average Control) strategy achieves low distortion of the current with less steady-state error,and it also avoids the capacitance design problems that exist in traditional method based on splitting-capacitor.But the WAC strategy is limited to the interference from grid and an neglected resonant frequency.In this paper,an active damping method is used to improve the grid-connected current quality and restrain the resonance of system while degrading the control system.In addition,a grid voltage feed-forward control strategy is proposed to resist the grid disturbance which can not only change the control transfer function,but also have a negative effect on active damping method.Effectiveness and feasibility of the proposed strategy are verified by the simulation results.
引文
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