基于桥臂能量控制的模块化多电平矩阵变换器控制策略

The modular multilevel matrix converter (M3C) has a cascaded modular structure, which is suitable for scenarios with medium- and high-voltage, high power and wide frequency ranges such as driving high-voltage high-power motors and flexible low-frequency transmission systems. However, due to the large number of system components and the presence of floating capacitors, the difficulty in controlling the M3C is significant, especially in terms of voltage equalization and ripple suppression of numerous floating capacitors in the system. A strategy based on bridge arm energy control is proposed, which is intuitive and simplifies the number of control layers. The goal of directly controlling the energy of each bridge arm in the converter is mainly achieved by setting the energy reference value of the bridge arm and controlling the bridge arm energy at present in real-time in the form of negative feedback. Aimed at each cascaded submodule within the bridge arm, a voltage equalization controller is designed. Finally, the feasibility of the proposed control strategy was verified through simulations.