基于dq坐标变换的单相逆变器控制技术研究

Research on Control Strategy of Single-phase Inverter Based on dq Coordinate Transform

针对单相逆变器给定信号和反馈信号均为正弦量,采用PI调节器不能实现无差跟随且对于周期干扰信号不能实现无差抗扰动,从而导致输出稳态精度受到影响的问题。采用单相坐标变换将交流信号变换到旋转坐标系下的直流量,确定了电压外环电感电流内环的瞬时值双闭环控制策略;搭建了以STM32为控制核心的单相逆变器实验样机并进行了相关实验,结果表明,在双闭环控制策略下逆变器输出电压波形可得到及时补偿,输出电压波形正弦度高,电压谐波含量小。

Single-phase inverter given signal and feedback signal are sinusoidal, PI regulator can＇ t be achieved with zero steady-state error and the periodic interference signal can＇ t be achieved with indifferent disturbance. Causing the output steady-state accuracy problems affected. Single-phase coordinate transformation was adopted to transform AC signals to a rotating coordinate system transforms a straight flow. The value control strategy of voltage as external loop and the value of inductor current instantaneous as inner loop was accepted. The experimental prototype employed STM32 as control core has been constructed. It is shown by the experimental results that output voltage waveform of the inverter can be compensated in time and has good sine degree and low harmonic distortion.