中文摘要：

针对电气化铁道的谐波、无功、负序及电分相等问题，讨论了采用Scott平衡变压器与综合潮流控制器（IPFC）构成的同相供电系统。提出IPFC直流侧电压PI均值前馈控制策略，可准确控制变压器副边电流幅值均衡，实现系统负序的完全补偿。为改善传统控制方法谐波含量高、直流侧电压波动大的不足，提出直流侧电流均值前馈控制策略。所提方法使系统具有良好的动态特性、稳定性及较小的稳态误差，且在牵引和再生制动工况下均适用。仿真分析验证了所提方法的有效性与正确性。

英文摘要：

Aiming at the problems in the negative sequence,harmonics,reactive power and electrical separation of electric railroad,the co-phase traction power supply system composed of Scott transformer and IPFC （Integrated Power Flow Controller） is discussed. ,A scheme of PI-mean feedforward control at IPFC DC voltage side is presented to properly control the amplitude equilibrium of transformer secondary current for the complete compensation of system negative sequence. A scheme of DC current-mean feedforward control is also given to suppress the harmonic content and smooth the DC voltage. The proposed control strategy has better dynamic performance and stability,as well as smaller steady-state error,suitable for both traction and regenerative braking conditions. Simulative results verify its correctness and effectiveness.