适用于高速电气化铁路的低成本电能质量综合补偿装置

摘要

To compensate the negative sequence and harmonic current of the traction power supply system, a comprehensive compensation scheme is proposed. The comprehensive compensation system is composed of railway power controller (RPC), thyristor controlled reactor (TCR) and thyristor switched capacitor (TSC). The working principle of the device is analyzed, and instantaneous current detection method based on the principle of phase demodulation is adopted to extract the active and reactive component in the load current. The reactive current allocation strategy is proposed to provide trigger signal for TSC and TCR. TSC and TCR are used to compensate the shortfall of reactive current for the heavy-loading and light-loading supply arm. Compensation capacity of RPC is greatly reduced, only providing negative sequence current, harmonic current of the traction system, and a small amount of reactive current used to adjust the actual compensating capacity of TSC, achieving the effect of negative sequence compensation and harmonic suppression. Simulation and experimental results show that the device has a strong ability to compensate negative sequence current and a good harmonic suppression ability, suitable for engineering application as a low cost.%　　针对牵引供电系统传统补偿系统治理效果欠佳且成本较高的问题，提出了一种适用于高速电气化铁路的低成本电能质量综合补偿方案。综合补偿方案由铁路功率调节器（Railway Power Controller, RPC）、晶闸管控制电抗器（Thyristor Controlled Reactor, TCR）和晶闸管投切电容器(Thyristor Switched Capacitor, TSC)构成。分析了综合补偿装置的工作原理，采用基于鉴相原理的瞬时电流检测法提取机车负载电流中的有功电流及无功电流分量。针对TCR、TSC及RPC无功补偿容量分配问题，提出了补偿装置的无功电流分配策略，根据分配策略为补偿装置提供控制信号。利用TSC和TCR分别补偿重载供电臂和轻载供电臂的缺额无功电流，铁路功率调节器的补偿容量大为降低，仅补偿牵引系统的负序电流、各次谐波电流及用于调整TSC实际补偿容量的小额无功电流，实现负序补偿和谐波抑制效果。仿真分析和样机实验结果表明了综合补偿装置负序补偿能力强，具有良好的谐波抑制能力，且降低了传统补偿装置的造价，易于工程应用。