effectiveness and optimal placement of bidirectional substations for regenerativebraking energy recovery in electrical network of metro system

Using bidirectional converters in metro substations, regenerative braking energy can be fed back to the ac grid to decrease the braking energy loss. in this paper, effectiveness of bidirectional rectifiers and their placement are investigated. a case study is provided for determination of optimal location and capacity of bidirectional rectifiers in 8 rectifier substations for different traffic scenarios in portion of line 1 of the tehran metro system. particle swarm optimization (pso) method is used for selection of optimal traction substation for inverter placement, finally, the results of simulation and optimization using the software built in matlab / symulink is presented. simulation results confirm the effectiveness of using bidirectional rectifiers as well as the optimization method.