Research Of Speed Regulating Device Based On Parallel Inverters

Abstract AC speed regulation has risen for the mainstream of electrical driving. At the range of middle low capacity, the PWM inverters of total numerical control which adopts self-shutoff apparatus have been used in industrial area. As for high power inverters of low voltage(voltage is 400V, and the power is from 400KW to 800KW),because the technique of manufacture is very difficult, for the moment ,the applied high power inverters of China at present mainly depend on import, so the cost is very high, which confine the application of high power inverter in industrial production, and also affect the course of production automation. Then it has more important value of research of using middle power inverters parallel to realize high power output.There are many methods for the topology structure of high power inverter. It is very common to use parallel inverter modules to get high power, but there are some problems such as more complex in technical structure and more rigorous of the modules' consistency in this method application. This paper adopted the scheme of using parallel inverters to realize the power synthesis. As for the parallel inverters,using current version two inverters'parallel connection can enlarge power with the purpose of high power export. It has some advantages such as line simplicity, easy realization, and is proved to be a feasible technology scheme.A speed regulating system which uses two parallel inverters and makes DSP for its nucleus is designed in this paper. Through the study of special digital signal processor TMS320LF2407A of Ti corporation for the motor control,the structure,theory and the design method of inverter based on this DSP which used in general inverter to complete some functions such as parallel connection, signal detection, AD conversion are grasped, theory in multiple with repose this strain DSP inverter's design method above with DSP for nuclear general purpose inverter complete include finish include parallel connection, signal detection, AD conversion, data processing, PWM generation, inhibitory realization of circulating-current are grasped,and use the software PSIM to simulate, and the simulation result proves this scheme's feasibility and validity. The author designed and debugged all of experiment circuits and control software, the experiment is carried out with the load of an AC induction motor, the result indicates that the performance of current equalization of the parallel inverters, the design of the system is reasonable and feasible, and it has practical value.