Electrical System Design And Research On Straddle Monorail Vehicles Rolling Testbed

To develop urban rail transit is the effective way to solve traffic congestion, noise, air pollution, energy conservation and other issues. At present many big cities have subway and light rail transportation which are operating or building. Chongqing is the first construction mono-rail traffic city of china.In order to test the traction performance of rail vehicles and ensure product quality, assembled rail vehicles generally need to carry out a series of type test and factory test adjustment, so railway vehicles are in formal run before the desired effect. Then the locomotive rolling test bed arises at the historic moment.This paper refer to the existing rolling stock rolling test bed design, full account of the unique structure of monorail vehicles, and design agency programs and Electrical system of single-track vehicles rolling test bed from the structure of single-track vehicles, traction and braking modes, etc. The main features of the system are:1. When the vehicles are under traction condition, dynamometer motor is equivalent to generator; the dynamometer motor is equivalent to motor when under braking condition. The two form mutual doubly-fed system that can better complete the vehicle test and performance test of the traction drive system and traction motor, so it can measure traction and braking characteristics of single-track vehicle under these two operating conditions.2. Rolling test bed adopts the way of reciprocal power fed. The energy flows between vehicles traction motor and dynamometer motor inside. The system's energy consumption is only the loss of the motor and converter, energy efficiency is greatly improved.Dynamometer is the core equipment of monorail locomotive test bed. The main circuit of electrical system adopts DC-AC configuration. In order to achieve energy feedback, this paper selects three-phase PWM converter, and established a model of three-phase voltage-type PWM rectifier, completed controller design of double closed loop control of voltage and current. Adopting voltage-oriented control PWM commute control strategy, the dissertation puts forward an easy digital arithmetic to realize VOC.Secondly, based on the mathematics model of induction machine, the dissertation deeply analyzes flux linkage and torque control theory of DTC and presents a reasonable voltage-vector switch table.At last, three-phase PWM rectifier and the direct torque control of induction motor are simulated by MATLAB/SIMULINK. Simulation results show that the dynamometer can work in two states:power generation and dragging. The dynamometer can not only absorb energy from the grid, but also feedback energy to the network. Direct torque control can basically meet the requirements of the dynamometer speed.