Design And Application On Electrical System Of DC Over-head Line Mine Railway Maintenance Vehicle

In current stage, our country's conveying device for mine mostly are over-head line locomotive and storage battery locomotive, whose electrical system mostly adopted DC transmission technique, the way of control is out of behind and exists much potential safety hazard, transportation cost is expensive, so it has become bottle-neck of further improving the minerals' quality. In recent years, with the development of power-electronic technology, computer technology, automatic control, its advantages, such as great driving, good braking ability, wide application, high technique index, good security and economical efficiency, etc have been widely used in the driving electric locomotive field.The aims of the study on this subject is to put AC transmission technique to use in the factories and the electrical system of mines electric locomotive and finish the task of changing from DC transmission to AC transmission and catch up with the developing countries in the driving electrical equipment field as soon as possible.This paper mainly deals with electrical control system of the DC over-head line locomotive by adopting AC frequency control transmission technique on the basis of PWM, adopting IGBT power model as on-off element to institute DC-AC voltage inverter, adopting three-phrase high precision PWM generator SA4828 and SCM(Single Chip Micyoco) forming control circuits ,changing the DC into three-phrase AC, and supply AC driving electric motor to drive rail-maintain locomotive. It mainly introduces electrical principles of driving mines electric locomotive and function of electrical control and illustrates about this locomotive circuit design thoughts, operational principle, hardware organization, and calculates technological parameter and chooses component, finishes circuit system design of electrical control function, explores and applies it into practice, and it works very well.The study content contains following points:(1) Analyzing theoretically and testing AC driving electrical control principle.(2) For frequency control as central part, analyzing its structure and principle, designing and calculating its technique parameter, calculating its electric locomotive parameter and choosing its parameter, analyzing and calculation on the braking resistor.(3) Having parameter calculating and analyzing the corresponding component's parameter of the control circuits and auxiliary circuits in electrical control system.(4) Finishing the principle design, function analysis and component selection of electrical control system.(5) Finishing the experimental work needed for electrical control design, realizing the operation of electrical control system, completely embodied the good operation of AC transmission technique in electrical control system.This system realizes the function of soft startup, soft turn-off function of electric locomotive by adopting frequency control technique, its voltage utilization ratio is better than normal , it has many advantages, such as simple control, few periphery circuits, visible energy saving high performance-price ratio. And it can meet the performance of AC driving frequency-converter . It was suited to rail haulage industry, such as: subway construction, excavating mdustry, coal industry, nonferrous metal industry, construction of tunnel; and it was also suited to underworkings for transportation driving.