在传统电流滞环控制的基础上,提出一种能动态调整滞环宽度的自适应滞环控制算法,应用于太阳能光伏并网逆变器的控制。以Matlab/simulink以及Matlab和Psim的接口模块Simcoupler为仿真平台,在滞环控制数学模型和算法的基础上构建光伏阵列,自适应滞环宽度计算器和滞环控制器的仿真模块;最后搭建以光伏模块,单相全桥PWM逆变器,滤波电感,负载和电网为电力元件的光伏并网逆变系统,并以自适应滞环控制器对逆变器进行开关频率的控制,仿真结果表明采用自适应滞环控制策略,能实现开关频率的固定化,电流滞环宽度动态调制,在开关频率较高的条件下,使注入电网的电流和电网电压同相,功率因数为1。
Based on conventional current hysteresis band control,an adaptive hysteresis band control algorithm featuring dynamically modulate hysteresis band is presented in this paper,and will be used in photovoltaic grid-connected inverter.In the platform environment of Matlab/Simulink and interface module Simcoupler of Matlab and Psim,the simulation modules of photovoltaic array,adaptive hysteresis band width calculator and hysteresis band controller are built based on the new mathematical models and novel algorithms;finally,the photovoltaic grid-connected inverter system composed of photovoltaic array,DC link capacitor,single phase full-bridge PWM inverter,filter inductor and power grid is created as well,the adaptive hysteresis band controller is integrated into the inverter system to control switching frequency,the simulation result indicates that the switch frequency could be fixed constant while dynamically and instantaneously modulating current hysteresis band width,at the result of synchronization of power grid voltage and inverter current and unity of power factor under the condition of higher switching frequency.