静止坐标系下基于最优时间序列的电压型PWM整流器电流预测控制

Stationary Frame Current Regulation of PWM Rectifiers Based on Predictive Control

有限状态预测控制能够实现静止坐标系下电压型PWM整流器的电流控制,但开关频率及稳态控制精度方面的缺陷限制了其进一步发展。针对这一问题,提出了基于最优时间序列的电压型PWM整流器电流控制策略。根据电网电压相位信息筛选非零矢量,基于电流变化特性预测模型得出不同矢量作用下的电流变化特性,结合电流给定值构建基于、轴电流误差的价值函数,以单个采样周期内电流误差最小为约束条件确定非零矢量作用时间。实验结果表明,本文提出的基于最优时间序列的预测控制策略能够有效弥补有限状态预测控制在开关频率及稳态控制精度方面的缺陷,在保证稳态控制精度的同时,实现静止坐标系下电流的准确、快速调节。

The finite control set model predictive control strategy can regulate α-and β-currents of pulse-width modulation （PWM） rectifiers. However, the main advantages are non-constant switching frequency and current ripples. This paper proposed a novel current regulation strategy of PWM rectifiers based on optimum time sequence in stationary frame. The proposed strategy selected active voltage vectors based on the location information of grid voltage vector. A cost function based on the current error was then constructed. The action time of each active vector was calculated by minimizing the cost function. The experimental results indicate that the proposed current control scheme achieves flexible current regulation in stationary frame, inheriting the merit of finite-state predictive control and realize the rapid dynamic response, but also ensure the constant switching frequency and improve the steady-state control effect.