模块化多电平换流器的启动控制方法

Startup Control Method for Modular Multilevel Converter

模块化多电平换流器作为新一代换流器,优点显著、应用广泛。通过分析模块化多电平换流器的拓扑结构、工作原理以及开关函数建立模块化多电平换流器动态特性的数学模型,进一步得出dq坐标系下的解耦控制器,由此实现对dq轴电流的控制。同时根据模块化与多电平的需求选择载波移相的脉宽调制方式,触发子模块实现换流器的控制功能。根据不可控充电方式,完成模块化多电平换流器的预充电,再通过建立的控制器实现模块化多电平换流器的启动。最后,在MATLAB/Simulink软件中仿真实验验证,仿真实验结果验证了提出的控制方法的准确性。

A modular multi-level converter with significant advantages and wide application is recognized as a new generation of inverters. By analyzing the topology, working principle and switching function of the modular multilevel converter, the dynamic mathematical model of the modular multilevel converter is established, and the decoupling controller in the dq coordinate system is further obtained, thereby realizing the direct control of the current of dq axis. At the same time, according to the modular and multilevel requirements, the modulation mode of the carrier phase shift is selected to trigger the sub-module to realize the control function of the converter. Pre-charging of the modular multi-level converter is completed by uncontrolled charging. The startup of the modular multilevel converter is implemented by established controller. Finally, simulation experiments are verified in MATLAB/Simulink software. Simulation results verify the accuracy of the proposed control method.