三电平城轨能馈装置中点电位平衡控制策略研究

Research on Neutral Point Potential Balance Control Strategy of Three-level Urban Rail Energy Feedback Devices

城市轨道交通站间距较短导致列车频繁启停,车辆再生制动过程会产生大量能量,随着国内城轨开通运行线路的增多,再生制动能量的有效利用已成为轨道交通普遍关注的话题。能馈装置应用在轨道交通牵引变电站,可以将车辆的再生制动能量回馈到上级电网,并维持牵引网电压稳定。针对三相三电平四象限能馈装置进行研究,提出只工作在能馈模式的城轨能馈装置的判据给定策略,同时针对三电平电路拓扑中点电位平衡问题,结合三电平空间矢量调制(SVPWM)控制策略进行中点电位平衡控制优化,最后通过实验验证了研究内容的可行性。

Due to the short distance between urban rail transit stations,the train operates between traction and brake frequently,so that a lot of energy are generated in the process of regenerative braking.With the increase of domestic urban rail transit operation lines,the effective utilization of regenerative braking energy has become a topic of general concern for urban rail transit.The energy feedback device applied in the traction substation of rail transit can feed back the regenerative braking energy to the superior grid and maintain the voltage stability of the traction network.three phase-three level-four quadrant energy feedback devices were studied,and an algorithm for determining the operation conditions was proposed.At the same time,aiming at the neutral point potential balance problem of three-level circuit topology,the control optimization of neutral point potential balance was carried out based on the three-level space vector pulse width modulation(SVPWM)modulation strategy.Finally,the feasibility of the research content was verified by experiments.