Simulation Experiment Study On Active Comprehensive Compensation System Of Traction Substation

In the current power supply system of the electrified railway traction, the problems of the electric-railway harmonic and reactive have received much attention. So many studies about the problems have also appeared. With the breakthrough development of manufacturing technology about the high-power semiconductor device, power electronic technology, micro-computer technology and other key technologies, it also promotes the development of active comprehensive compensation of traction substation rapidly and perfectly. The system of active comprehensive compensation is dynamic which consists of balanced transformer, power electronic equipments, advance detection and control methods. The system has high performance-to-price ratio, academic research value and engineering applications, so many scholars pay much attention to it at present.Aiming at harmonic, reactive power and negative sequence current problems which happened in three-phase power supply of 110kV/27.5kV, the thesis uses Y/>/V balanced transformer and conducts the simulation under the conditions of laboratory. According to the usual using condition, the thesis chooses 380V/220V balanced transformer as the research setting in order to simulate the rail-powered three-phase 110kV transformer balanced working condition. It is used for solving the problems of active comprehensive compensation devices.Firstly, the thesis analyzes the topological structure and working principle of the active comprehensive compensation system and discusses the method of the single-phase circuit harmonic and reactive power compensation detection. It also analyzes the control method of 4-quadrant converter and DC side voltage. The simulation model of active comprehensive compensation is demonstrated to be correct and acceptable on the base of Matlab. Secondly, according to the simulation results, hardware circuit is designed and selected appropriately, as well as the corresponding PCB. In order to realize corresponding control system of voltage source PWM converter, better hardware and software design, the thesis selects the Hall voltage, the Hall current sensors and other detection devices as well as the corresponding circuit which can complete the control function. Finally, the thesis also chooses TI's new high-performance DSP chip TMS320F28335 as the core of control and Mitsubishi's intelligent power module(IPM)PS21865-P as the power device to complete the low-power experiment of active comprehensive compensation system.The thesis focuses on the hardware circuit design and realization of the active comprehensive compensation for experiment use in laboratory condition. Important content of this thesis includes hardware circuit design, device design and selection, the controller design, device development and the prototype experiment. By building an intelligent power module (IPM)PS21865-P and TMS320F28335 DSP controller as the core of the main circuit, and designing the sensor detection circuit, voltage zero detection circuit, signal regulate circuit, driving isolating circuit,power circuit and so on,the flow of software design and programming have been taken for the active comprehensive compensation system,the final devices are designed to connect the hardware and software to complete the commissioning of the system, and debugged the experimental prototype system to verify the practical feasibility and correctness.