基于周期控制的载波移相策略研究

Research on Carrier Phase-shift Strategy Based on Periodic Control

为了抑制系统内部网侧四象限变流器产生的高频谐波,减小对电网的谐波污染,防止产生车网高频谐振,提出一种基于周期控制的载波移相策略及实现方法。针对同一列车多个牵引系统之间无同步线的情况,提供一种以网压过零点为参考,通过微调PWM载波周期,实现准确且稳定的校正载波移相角的方法。通过Matlab/Simulink仿真及混合动力动车组牵引系统运行实验,验证该载波移相策略的可行性及有效性,为工程实践提供指导。

In order to reduce the high-frequency harmonics generated by the single-phase four-quadrant converter of the traction locomotive, reduce the harmonic pollution to the power grid, and prevent the high-frequency resonance of the locomotive and network, an implementation method of carrier phase-shift strategy based on periodic control was proposed in this paper. According to the condition that there is no synchronization line between different traction systems in one locomotive, an accurate and stable method of correcting the carrier phase-shift angle was proposed, which is through fine-tuning the PWM carrier period with reference to the zero-crossing of the network voltage. Through Matlab/Simulink and traction system running experiments on hybrid EMUs, the feasibility and effectiveness of the carrier phase-shift strategy were verified, which provides guidance for engineering practice.