光伏离网型SL-qZSI多目标优化排序模型预测控制

MULTI-OBJECTIVE OPTIMIZATION RANKING MODEL PREDICTIVE CONTROL OF PVOTOVOLTAIC OFF-GRID SL-qZSI

开关电感型准Z源逆变器能提高光伏发电系统的可靠性和能量转换效率,其有限集模型预测控制(FCS-MPC)存在多个控制变量,权重系数调整困难,提出一种基于多目标优化排序的光伏离网型开关电感型准Z源逆变器模型预测控制策略。首先根据电感电流的预测值来判断下一个控制周期的状态,若为非直通状态时,分别计算负载电流和电容电压的代价函数,并将其按照从小到大的顺序进行排序,再将这两个排序值进行相加得到排序和,最小的排序和所对应的开关状态将被应用到逆变器的下一周期的开关状态,有效消除了传统FCS-MPC策略的权重系数。仿真分析和实验结果表明,所提控制策略具有良好的稳态特性和动态特性。

The switched-inductance quasi-Z-source inverter can improve the reliability and energy conversion efficiency of photovoltaic power generation system,however,its finite control set model predictive control(FCS-MPC)has multiple control variables and difficult to adjust the weight coefficients.This paper proposes a photovoltaic off-grid switched-inductance quasi-Z-source inverter model predictive control strategy based on multi-objective optimization ranking.Firstly,the state of the next control cycle is judged based on the predicted value of inductor current,and if it is a non-through state,the cost functions of load current and capacitor voltage are calculated separately and sorted in the order from smallest to largest,and then the two sorted values are summed to obtain the sorted sum,and the switching state corresponding to the smallest sorted sum will be applied to the switching state of the next cycle of the inverter,which effectively eliminates the weighting factor of the traditional FCS-MPC strategy.Simulation analysis and experimental results show that the proposed control strategy has good steady and dynamic characteristics.