单周期控制在牵引传动系统拍频抑制中的应用

针对电气化铁路单相交流供电及列车网侧牵引变流器拓扑特点所引起的牵引电机拍频问题,首先分析了直流侧电压存在2倍电网频率脉动的特征,针对直流侧无LC滤波器的交-直-交电力牵引传动系统,揭示了当逆变器的工作频率接近2倍电网频率时电机拍频现象最为严重的原因。然后利用单周期控制在输入电压脉动时仍能满足伏秒平衡的原理,并结合间接转子磁场定向矢量控制,提出将单周期控制算法作为牵引逆变器的调制策略,实现牵引逆变器-电机系统的无拍频控制。最后,搭建基于OP5600/RT-LAB实时仿真器与DSP TMS320F2812控制器的牵引传动系统半实物实验平台,对传统空间矢量脉宽调制与单周期控制算法进行了半实物实验对比验证,结果表明单周期控制算法能有效地抑制电机的拍频现象。

One-cycle control for beat-less frequency control application of traction drive system

The single-phase AC power supply source in electrified railway and characteristics of the grid-tied converter topology in train leads to beat frequency phenomenon of motor.Twice line-frequency ripple of DC-link voltage in traction converters was analyzed.And the reason why the more severe beat-frequency phenomenon happens when the fundamental frequency of the output phase-voltage of inverter is close to twice the line-frequency was described.And then,combining indirect filed-oriented control scheme,one cycle control was carried out to achieve beat-less frequency control for the traction inverter-motor system without LC filter in the DC-link,which satisfies the principle of voltage-second balancing even when the DC-link voltage is fluctuating.Finally,the hardware-in-the-loop(HIL) platform with OP5600/RT-LAB real-time simulator and DSP TMS320F2812 Controller was developed to compare with the traditional space vector pulse-width modulation strategy and one cycle control.The HIL experimental results verify that OCC scheme can effectively suppress the beat frequency phenomenon.