Combined Inverter Design And Research

With the development of electronic technology, the requirements for better power system are enhanced. Inverter power system is developed to achieve higher efficiency, higher power density, higher dependability, online communication and watching. As an equipment of DC to AC power conversion, sine inverter takes on the broad market in both industry and folk applications. In the paper, a whole digital sine inverter is introduced, which is universal, programmable, intelligent, and combinable.At the beginning, the basic topology and working theory of the inverting circuit is introduced. Following, the paper analyses and discusses the issues of hardware composing, parameter choice, controlling methods, and software implementing in the system.To show the designing and analyzing process of the control system, the article mainly discussed two parts. One is the power circuit part, which includes designing of the output filter and the IGBT drive circuit based on M57966L, the way for IGBT controlling and Protection and also the control circuit based on DSP. The other is control system for the inverter, which includes the way of Producing SPWM wave using Microprocessor, the hardware system of the inverter and the other assistant circuit. Tested by Saber simulation and small power experiment, the designing Project "adjusting output voltage by changing on and off time of the SPWM" is Practical. The author has completed development of the hardware and software for the control system on the experiment. Finally, the sine inverters have been developed successfully and the auto-synchronous operation of the three single-phase inverters is implemented.A new controlling method to the auto-synchronous operation of the three single-phase inverters is issued in the paper, that is, three independent single-phase inverters can implement three-phase symmetrical AC output by being connected with each other, which can avoid the effect to the output of the inverter because of the asymmetric load.The following works has been finished during this item:Firstly, the topology of three- phase inverter is analyzed. Several current topologies are introduced. The circuit topology and work principle are analyzed in detail. Each part of the circuit is simulated in detail. Secondly, based on circuit...