双闭环控制的三电平逆变电路Simulink仿真实验

Simulink simulation experiment of three-level inverter circuit with double closed-loop control

针对开环的三电平逆变电路稳定性差、动态响应慢、带载能力弱等问题,提出了电压、电流双闭环的控制方案。选取二极管箝位式三电平逆变电路作为被控对象,建立其在同步旋转坐标系下的数学模型,分别对电流环和电压环进行设计。电流环包括基于d、q轴的电感电流前馈解耦及PI参数的设计;电压环包括基于d、q轴的电容电压前馈解耦及控制器参数的设计。在Simulink仿真实验平台上,建立了双闭环控制的三电平逆变电路的仿真模型,分析了突变负载情况下双闭环控制的逆变输出电压和电流的仿真波形。

Aiming at the problems of open-loop three-level inverter circuit poor stability, slow dynamic response, weak carrying capacity, the voltage-current double closed-loop control scheme is proposed. The diode-clamped three-level inverter circuit is regarded as the controlled object. The math model of inverter circuit on two-phase synchronous rotating coordinates is established. The designs of current loop and voltage loop are carried out respectively. The current loop includes the inductance current feed-forward decoupling based on dq axis and the design of corresponding PI parameters. Voltage loop includes the capacitance voltage feed-forward decoupling based on dq axis and the design of controller parameters. The simulation model of three-level inverter circuit with double closed-loop control is built in the Simulink simulation platform. The waveforrns of the output voltage and current of the double closed-loop control under the condition mutation loads are analyzed.