【摘要】 针对带LCL滤波器的并网逆变器的不稳定性,提出一种基于逆变器侧电流反馈滑模控制策略,间接控制并网电流,以避免系统谐振。将并网电流参考值看成和电网电压成比例,推导出逆变器侧参考电流,解决间接控制并网电流相位滞后问题。理论推导滑模变结构控制律在并网逆变器应用的存在性和系统稳定性,所提控制策略无需增加额外的传感器。应用电压基波信号估计,以减轻电网高次谐波对系统控制的影响。仿真实验证明提出的控制策略可实现逆变器并网电流与电网电压同频同相,提高了系统的鲁棒性。更多还原

【Abstract】 Aiming at the instability of grid-connected inverter with LCL filter,the side current-feedback sliding mode control strategy of inverter was proposed to avoid the system resonance by controlling on-grid current indirectly. In order to solve the phase lag of grid current,the inverter side reference current is calculated based on the reference value of ongrid current is proportional to the grid voltage. It is theoretically derived that the sliding mode control(SMC)can be used in on-grid inverter and the system is stable. The proposed strategy does not require additional sensors. Grid voltage fundamental signal estimation is used to release the impact of higher harmonics on system control. The simulation results verify that the proposed control strategy can keep frequency and phase of on-grid current as same as that of grid voltage,and improve the robustness of system.更多还原