In order to absorb the regenerative braking energy of trains, supercapacitor energy storage systems (ESS) are widely used in subways. Although wayside ESS are widely used, because of the influence of no-load voltage, and so on, a wayside ESS cannot absorb all the regenerative braking energy in some special cases, and the brake resistor is still activated, which leading to the wasting of energy. In order to completely replace the on-board brake resistor, this paper configures a certain on-board super-capacitor, and based on a DC-side series super-capacitor topology, proposes a hierarchical optimization energy management strategy (EMS). The EMS is divided into three layers: Firstly, the strategy can increase the inverter-side voltage in a short time without changing the traction network voltage, and improve the train braking characteristic curve by utilizing the short-time overvoltage capability of the inverter and the motor; Secondly, by coordinated control with a wayside supercapacitor, the residual regenerative braking energy can be absorbed even in special cases; Finally, based on loss calculation and current prediction, this strategy can effectively reduce the system loss by adjusting the DC voltage on the inverter-side. The proposed control strategy is validated through RT-LAB experiment, and the experimental results agree well with the theory.

中文翻译：

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考虑列车电制动特性和系统损耗的车载超级电容器储能系统分级优化

为了吸收列车的再生制动能量，超级电容器储能系统（ESS）被广泛应用于地铁。虽然路边ESS应用广泛，但由于空载电压等影响，在一些特殊情况下，路边ESS不能吸收全部再生制动能量，制动电阻仍被激活，导致浪费活力。为了完全替代车载制动电阻，本文配置了某块车载超级电容器，并基于直流侧串联超级电容器拓扑结构，提出了分级优化能量管理策略（EMS）。EMS分为三层：第一，该策略可以在不改变牵引网电压的情况下，在短时间内提高逆变侧电压，利用逆变器和电机的短时过压能力，改善列车制动特性曲线；其次，通过与路边超级电容器的协调控制，即使在特殊情况下也可以吸收剩余的再生制动能量；最后，基于损耗计算和电流预测，该策略可以通过调整逆变侧直流电压来有效降低系统损耗。通过RT-LAB实验验证了所提出的控制策略，实验结果与理论吻合良好。该策略可以通过调节逆变侧直流电压有效降低系统损耗。通过RT-LAB实验验证了所提出的控制策略，实验结果与理论吻合良好。该策略可以通过调节逆变侧直流电压有效降低系统损耗。通过RT-LAB实验验证了所提出的控制策略，实验结果与理论吻合良好。