轨道交通永磁同步牵引系统发展概况与关键技术综述

Review on development and key technologies of permanent magnet synchronous traction system for rail transit

为系统分析和总结轨道车辆永磁牵引系统控制技术研究与发展趋势,介绍了永磁同步电机作为牵引电机应用于轨道交通领域的优缺点和国内外永磁同步牵引系统的应用情况;回顾了大功率牵引逆变器在低开关频率下的控制技术和永磁同步电机牵引控制技术,分析了脉宽调制策略、弱磁控制等关键技术的设计思想、研究方法等;总结了近几年国内外研究成果,讨论了各类控制方法的优点和局限,并展望了永磁同步电机在轨道交通牵引领域的发展前景和面对的挑战。研究结果表明:内置式永磁同步电机适用于直驱系统,具有体积小、效率高等优势;牵引逆变器通常采用混合脉宽调制策略,低频段采用异步调制,中频段为同步调制,方波工况下采用单脉冲调制,其中特殊同步调制下系统动态性能的提升和不同调制方法之间的平滑切换是牵引逆变器脉宽调制技术的难点;电机控制策略主要针对基于双电流调节器、电压矢量角弱磁控制和方波工况下弱磁控制这3种高速运行区的弱磁控制方法进行研究;在前期研究的基础上,应进一步考虑永磁同步电机的无位置传感器技术、故障在线诊断与预测和高精度参数辨识问题;牵引传动系统的机电耦合特性和短路故障处理是今后重点关注的研究方向。

To systematically analyze and summarize the technologies and development trend of permanent magnet traction system control, the advantages and disadvantages of using the permanent magnet synchronous motor(PMSM) as the traction motor in rail transit were introduced, and the applications of permanent magnet synchronous traction systems in at home and abroad were illustrated. The technologies those control high-power traction inverters at low switching frequencies and control permanent magnet synchronous traction motors were reviewed to analyze the design concepts and research methods of key technologies, such as the pulse width modulation strategies and field-weakening control. Investigations of recent research results were carried out to illustrate the advantages and limitations of various control methods, and the prospects and challenges of PMSM in the field of rail transit traction were predicted. Research results show that the built-in PMSMs are suitable for direct drive systems, and their small volumes and high efficiencies make them superior. A traction inverter usually adopts a hybrid pulse width modulation strategy. The asynchronous, synchronous, and single-pulse modulation are used in low frequency bands, middle frequency bands, and under square wave conditions, respectively. Improving the system’s dynamic performance under special synchronous modulation and ensuring the smooth switching between different modulation methods are the most difficult aspects of traction inverter pulse width modulation technologies. The motor control strategy mainly focuses on three field-weakening control methods in high-speed operation areas, such as field-weakening control based on dual current regulators, field-weakening control with voltage vector angles, and field-weakening control under square wave conditions. Based on the previous research, future studies should include the sensorless technology, on-line fault diagnostics and prediction, and high-precision parameter identification of PMSMs, and the electromechanical coupling characteristics and short-circuit handling of traction drive systems are the key research directions in the future.