Matching-Control of Wind Power System Based on Current Source Converter

The weak grid lacks frequency support capability and may cause the broadband oscillation because of the coupling of the traditional vector control loop of current and the phase-locked-loop (PLL). To solve this issue, this paper presents a new method applied to the permanent magnetic synchronous generator (PMSG)-based wind power converter which is based on current source converter (CSC) and is called “Matching-Control”. In contrast to the conventional PLL-based synchronization method, the Matching-Control makes the grid side converter (GSC) realize self-synchronization by adopting the intrinsic dynamics of the DC-link inductor so the PLL could be removed and there will be no coupling problem of those control loops. An additional inertia transmission control loop is added to the machine-side control loop to improve the inertial response ability after receiving the frequency information transferred by the GSC and then utilizes the kinetic stored in the rotor of wind turbines to support the recovery of the grid. Therefore, under the Matching-Control, wind power converters show the characteristics of a synchronous generator and needs no PLL to keep synchronization with the power grid. Finally, on the Simulink/MATLAB simulation platform, the feasibility of the proposed method and the correctness of the theoretical analysis are verified.