The Research Of DC Chopper Speed Control System For Speed Sensorless Electric Locomotive

The mine is the important constituent of the national energy. Along with the fast development of national economy, the demand of mine is more and more big. Since the introduction of electric locomotive from other country, the mine electric locomotive has been the most important transportation form of the mine. Now, however, the most of electric locomotive are use the string resistance for speed modulation. Although this method is quite mature, massive energy was wasted in the resistance, this violates with the conservation of energy, therefore the improvement of the speed modulation method is urgently. As the fast development of the microcomputer controller and the electronic technology, an advanced speed modulation appeared,that is DC chopper. The DC chopper saves massive energy, also realized stepless speed regulation and has big starting power.This paper studied a DC chopper system that suitable for electric locomotive of mine. In the Doulble-Closed loop control system of speed and current, the traditional speed gain method is to install the speed-voltage generator or the optical encoder, this methods has disadvantages, such as the anti-jamming is not strong, the precision is insufficient and increase the cost etc. The Speed sensorless control system of DC motor is now the research hot sport. In the paper, an online speed estimation of electric locomotive was proposed which is based on the extend Kalman filter(EKF) algorithm.The technology applied in the electric locomotive has certain innovation, and has good prospect of application. Regarding the closed-loop control of speed, the traditional control method is PID control, the fuzzy control was applied in this paper, and obtained quick dynamic response.The EKF simulation model and Double-closed loop simulation model has been established, and the simulation results have proved that the system designed in the paper has good control performance. Also, a DC chopper was designed in the paper,and have completed the hardware and software design.In the paper, a significant attempt has been carried out in the sensorless speed regulation of DC motor, and has obtained gradual research results.