| This dissertation studies IGBT,which is a new type large power thyristor,and its applying technique. According to its lots of advantage,a scheme of remodeling original locomotive resistance-load test bed has been proposed which will make it automatic and numerical.Locomotive load test is a very important link of railway department repairing locomotive. At present,there are two modes of load test. One is water-resistance load;the other is resistance-load. The resistance load mode is developing and it can protect environment. But the original locomotive resistance-load test bed adopts SCR as switched element,as a result,switched circuit cannot regulate the current freely,and the speed of motor with air-blower cannot be regulated too. The new resistance-load test bed has been applied IGBT> technique of computer measurement and controK PWM control technique and coefficient resistantce(numerical technique),consequently,it can regulate the current freely process data and analyze the result and so on.In chapter l,the present state of locomotive load test is summarized;the defect of water resistance-load and original resistance-load is analyzed;then IGBT being applied in resistance-load test bed is proposed and the trend of the thyristor is forsightIn chapter 2,the principle of IGBT driving & protecting circuit is studied,and the dissertation introduces the hybrid circuit designed for driving IGBT module and its protection technique.In chapter 3 and 4,a scheme of remodeling original locomotive resistance-load test bed is present. According to the scheme,all parameters are calibrated,the dissertation research the application of single-unit IGBT and PWM technique in irreversible speed regulating system of a DC motor,and analyzes signal generating of PWM and its feedback control circuit.In chapter 5,the results of two tests are analyzed,and the feasibility of IGBT applied in locomotive resistance-load test bed is affirmed.Finally,a summarization of the dissertation is given.
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