基于YNvd平衡变压器的电铁背靠背SVG补偿系统研究

Electrified railway back-to-back SVG compensation based on YNVD balance transformer

针对电气化铁道牵引供电系统存在大量的谐波、负序、无功等问题,提出了基于YNvd平衡变压器的背靠背SVG补偿方案。2个SVG通过直流耦合电容背靠背连接在一起,如果两臂的负荷相差较大,中间的直流耦合电容便可以根据负荷的差值进行功率传递,使2个供电臂的负荷基本相同,这样通过平衡变压器将负荷等效到系统一次侧就成为对称负荷,从而解决负序问题。还能兼补牵引负荷引起的谐波和无功问题,达到电能质量的综合治理。通过MATLAB/Simulink仿真,验证了该方案的正确性。

According to the problems of negative sequence, reactive and harmonic caused by traction power supply system, back-to-back SVG compensation scheme based on balance transformer is proposed. Two back-to- back SVGs together use a DC capacitor, when the loads of two arms are different,active power can pass through the middle of the DC capacitor and then the loads can be nearly equal, so the loads can be equivalent to symmetrical load at the primary side of the transformer so as to solve negative sequence problem and also to solve harmonic and reactive power problems caused by the traction load. Simulation result of the system is presented to verify the system feasibility.