Research On DC1500V Metro Auxiliary Power Supply System

In electrical metro and light railway, the auxiliary power supply system always plays an important role. It supplies all of the on-board loads, except the main traction motors. This thesis proposed a complete scheme of 160kW auxiliary power supply system based on an indirect inverter topology for a practical project, and did a detailed theory research work and a lot of experiments.This thesis analyzed several most used topologies of auxiliary power supply system, and chose the indirect inverter topology. This thesis introduced the whole scheme in two aspects: function and actual structure, and the small signal mathematical model of the full bridge was analyzed in detail. Aimed to keep the dc-bus voltage of the inverter, the output voltage of the inverter, the output voltage and current of the battery charger stable, this thesis proposed three different close-loop control schemes for each one. At the same time the shift control method based on single DSP chip was implemented successfully. The space vector pulse width (SVPWM) algorithm was also introduced in this paper. Considering security and stability, this thesis designed a complete fault detection and protection algorithm for full bridge, inverter and battery charger. The protection of IGBT was also discussed in details.In order to obey to electric module design concepts, the auxiliary power supply system proposed in this paper divided the whole system into three parts: full bridge converter, three phase inverter and battery charger. Each part's signal acquiring, control signal handling and IGBT diver signal firing were introduced in details. The component parameters of hardware of each part were designed respectively, and the method of designing power transformer and electric filter was also introduced. The communication system of the auxiliary power supply system was introduced in details and the multiple function vehicle bus (MVB) was also introduced. At the end of this thesis, some experimental results got from a 160kW engineering prototype were given, which proved the scheme proposed in this thesis met the requirements of the auxiliary power supply system, and performed very good dynamic and static response features.