Redundant Design Of PWM Rectifier Applied To Arc-Suppressing Power Supply

ABSTRACT:As electric railway begins to develop in the direction of high-speed and heavy-hauling,the arc of the joint section of the articulated phase insulator has become an urgent problem to be solved.At present,technology of automatic passing neutral section is becoming more and more mature.The arc-suppressing power supply is added to the device of automatic passing neutral section.By applying the amplitude-and phase-controllable arc-suppressing voltage to adjust the current relationship of the neutral section,the problem can be realized.Due to the particularity of the application and working state,the arc-suppressing power supply needs to ensure high reliability and stability to achieve the arc-suppressing function and ensure the normal operation of the railway system.In this paper,combined with the development of arc-suppressing power supply,the redundant design of PWM rectifier is studied around the function realization and reliability improvement of PWM rectifier parallel system for arc-suppressing power supply.The model establishment and control strategy research and control of three-phase PWM rectifier are completed.In this thesis,the three-phase PWM rectifier is modeled and analyzed.The mathematical model of three-phase stationary coordinate system,two-phase stationary coordinate system and synchronous rotating coordinate system is established.The feedforward decoupling based on two-phase synchronous rotating coordinate system is studied.The direct current control strategy and the design method of the voltage outer loop and the current inner loop are given.Then,for the redundant parallel system of PWM rectifier,the mechanism of parallel circulation generation is analyzed and the circulation model is established.On this basis,the design of the parallel system control scheme of the arc-suppressing power supply PWM rectifier is carried out,and the synchronous control scheme based on the hardware interconnection of the dual control system and the operation state monitoring method based on the CAN communication information interaction are determined.The circulation of the system is simulated and analyzed.Finally,the parameter design of the main circuit and software design of PWM rectifier are completed.The parameter design method and software structure for implementing redundant control function and fault detection and processing are given.A small power experimental platform is built.Parallel experiments of the PWM rectifiers verify the effectiveness of the aforementioned control scheme and the applicability to the arc-suppressing power supply.