Study On Detection And Control Of Active Comprehensive Compensation Device On Electrified Railway

Power quality deterioration and damage to the power system caused by ecectrified railway traction power supply system has been paid extensive attention, researching on technology and equipment for better control of the problem of power quality, which is caused by electrified railway traction power supply system, has become important issues for experts and scholars at this stage.Aiming at the problem of the harmonic and reactive power in electrified railway traction power supply system, the thesis analyzes present detection and control method of the harmonic and reactive power, according to the results, thesis studies the method of control and detedtion for the active comprehensive compensation device in electrified railway.First, the thesis analyzes two common-used single-phase circuit harmonics and reactive power detection, the method based on the phase distinguishing technology can rapidly detect but it have to design phase-locked loop, while in recent years scholars have proposed single-phase circuit without phase-locked loop method of detection but has a bigger computation. So thesis applies the principle of synchronous detection method from three-phase circuit to single-phase system, simulation shows the accuracy of the method in detecting the harmonic and reactive power, it can detect exactly and has small computation and good real-time in the case of voltage distortion.Then the thesis analyzes the method of comprehensive compensation device control, including current tracking control and DC voltage. The control of the DC voltage uses the active power conservation pattern to avoid obtaining parameters of Proportion Integration(PI) control. Research on the control of the converter including unipolar and bipolar hysteresis loop control control, analyzes the switch frequency of bipolar hysteresis loop control and optimized unipolar hysteresis loop control. The experimental results demonstrates the superiority of optimized unipolar hysteresis loop control.According to the analysis and research in the first few chapters, a hardware experimental platform of comprehensive compensation system was established, and the design of the control board was finished, at the same time, the design scheme of software and hardware was given, and a soft-start scheme for practical applications has been proposed.Experimental results show the correctness and feasibility of the detection and control methods, hardware and software solutions in this thesis.