The Study And Design Of Single-phase High Speed Trains Isolated Inverter

With the rapid development of the national economy, the demand of high quality electrical energy has been increasing recently. It draws much attention of researchers to design the inverters with simple structure, excellent static and dynamic performance and high load carrying capacity. In recent years, high speed trains have developed rapidly in China. Based on this background, this paper analyses the control strategy of 110VDC to 220V/50Hz inverter in the auxiliary power supply system of high speed trains, and then designs a 3kVA single phase isolated inverter, which can be used as the power supply for computers, vacuum cleaners and other electrical equipments in high speed trains.Firstly, this paper discusses the hardware design scheme of the inverter power supply system, and then completes the hardware design of the single-phase inverter system according to the design requirements. The hardware system can be divided into four parts including inverter main circuit、drive circuit、control circuit and auxiliary power.Next, this paper establishes the mathematical model of the main topology of the single phase segregation inverter power supply. This system uses the voltage, current instantaneous value feedback control strategy to enhance the control effect, after the comparion of performance between inductor current feedback and the capacitor current feedback, the inductor current feedback control strategy has been selected. In order to simplify the controller design and enhance the control performance of the system, load current feed-forward and output voltage feed-forward decoupling links are adopted. To realize no static difference and fast tracking of the given AC voltage signal, outer loop voltage non-ideal proportional resonant control and inner loop current proportional controller control structure have been introduced in this system. The control effect of voltage and current double closed loop feedback control strategy is verified by PSIM software simulation.At last, this paper completes the software design of the single-phase inverter system, the flow chart of the main program of the system and the flow chart of each interrupt routine are given. Then, the 3kVA experimental prototype is manufactured according to the hardware and software design in this paper, and the principle verification experiment is carried out. It proves that the design of this system is reasonable and feasible according to the analysis of the relevant waveform and data obtained in the experiment.