一种光伏并网逆变器的混合控制策略研究

A Hybrid Control Strategy for Photovoltaic Grid-connected Inverter

光伏并网逆变器模型是一个非线性强耦合的系统,光伏电池输出电压受外界光照强度、环境温度等因素的影响。针对以上特点,提出了采用自抗扰控制(ADRC)技术和无源控制(PBC)理论相结合的光伏并网逆变器双闭环混合控制策略。电压外环采用自抗扰技术来保持直流侧电压的稳定并与采用PI控制进行了比较;电流内环采用无源控制理论对并网侧电流进行dq轴解耦,实现对有功电流和无功电流的分别控制并可使系统具有优良的静、动性能。Matlab/Simulink仿真和实验结果表明,所设计的系统具有良好的鲁棒性和动态性能,所设计的逆变器控制策略是可行的。

Photovoltaic （PV） grid inverter model is a nonlinear and strong-coupling system as the output voltage of the photovoltaic battery is so sensitive to the light intensity and temperature of the environment. For these reasons, a double closed-loop control strategy was proposed based on ADRC and passivity-based control. The outer loop used the ADRC to maintain the stability of the DC voltage which was proved to be better than the control strategy of PI, while the inner loop used the passivity-based control to decouple the current of dq-axes, which realized the respective control of the active and reactive current and had good statically and dynamic performance. The experiment results showed that the system had good robustness and dynamic performance, the inverter control strategy was feasible.