【摘要】 针对光伏电池输出特性的非线性,本文提出一种单级式光伏并网逆变器的非线性综合控制策略。该策略采用状态反馈线性化的非线性控制方法,实现逆变器有功电流和无功电流的精确解耦控制;采用自抗扰控制设计逆变器直流母线电压环,补偿系统建模参数误差对反馈线性化的不利影响,提升并网逆变器的控制鲁棒性;在有功电流与无功电流精确解耦控制、电压环大范围稳定运行的基础上,采用基于有功电流和电压环输入误差信号的变步长扰动最大功率跟踪方法,可避免光伏阵列最大功率点的误判。所提非线性综合控制策略通过状态反馈电流环、自抗扰电压环和变步长扰动最大功率跟踪算法的有机结合,有效提升了逆变器的整机控制性能。仿真和实验表明了该控制策略的正确性和可行性。更多还原

【Abstract】 Due to the nonlinear output characteristics of photovoltaic(PV) cells,this paper presents a comprehensive nonlinear control strategy apply to the single-stage grid-connected PV inverter.In this strategy,the active and reactive currents of the inverter are controlled decoupling exactly by nonlinear feedback linearization controller.The active disturbance rejection control is employed to the dc voltage regulator of the inverter,so the system mathematic modeling parameter error on the harmful effects of feedback linearization is compensated,and the control robust of the system is improved.With the active and reactive currents are exactly decoupling controlled and the voltage regulator has steady stability.A variable perturbation step maximum power point tracking(MPPT) technique,which based on the active current and the signal error of the dc voltage regulator,is designed to avoid miscalculation maximum power point of the PV array.The comprehensive nonlinear controller promotes effectively the control performance of the inverter by integrating the feedback linearization current loop,the active disturbance rejection voltage controller and variable perturbation step MPPT technique together.Simulation and experimental results show that the proposed strategy provides validity and feasibility.更多还原