三相-两相牵引变电所用无功动态补偿与谐波治理混合系统的研究

Hybrid Var and Harmonic Dynamic Compensator and Application to Three-two Phase Traction Substation

针对单相牵引负荷波动性大,随机性强,造成大量谐波、无功及负序分量的特点,提出一种应用于电气化铁路的单相无功动态补偿与谐波治理混合系统(hybrid var and harmonic dynamic compensator,HVHC)。系统由混合型有源电力滤波器(hybrid active power filter,HAPF)及静止无功补偿器(static var compensator,SVC)组成,其中SVC包括晶闸管投切电容器(thyristor switched capacitor,TSC)和晶闸管控制电抗器(thyristor controlled reactor,TCR),用来动态连续补偿无功功率,HAPF用来动态抑制电网及无功补偿装置产生的谐波,电力机车产生的负序分量可通过在平衡变压器接线方式下控制2个牵引供电臂的负载来消除。提出HAPF和SVC复合控制策略及分频控制方法,可有效地消除两者之间的耦合,提高单相系统谐波及无功电流的跟踪精度,克服电网电压畸变对系统的影响。仿真及实验结果证明该系统响应速度快,抗干扰能力强,治理效果满足要求。

A novel hybrid vat and harmonic dynamic compensator （HVHC） is proposed in this paper, it is suitable to single-phase traction load which is varied in random and fluctuant resulting in high amount of harmonics, reactive power demand and negative sequence current. It is composed of hybrid active power filter （HAPF） and static var compensator （SVC）, SVC is composed of thyristor switched capacitor （TSC） and thyristor controlled reactor （TCR）. They are used to compensate reactive power dynamically, while HAPF is used to restrain harmonics dynamically. Negative sequence caused by electric locomotive can be eliminated through controlling the load of each power supply section under the connection mode of balancing transformer. Hybrid control strategy and dividing frequency control method are proposed to eliminate coupling relationship between HAPF and SVC, the current tracking accuracy of the system is improved and influence made by voltage distortion is overcome profiting from the proposed method. Simulation and experimental results have shown the validity of the proposed system.