Design And Research Of Three-phase Inverter Based On DSPIC

With the rapid development of power electronic technique, much electrical equipment has special requirements. In order to obtain high-quality power supply, the AC power is converted into the necessary power forms by the inverter. The primary objective of this paper is to solve an important issue, which is to convert the DC power supplied by batteries or AC power supplied by the generators into the required power forms in remote areas and no grid access for field operations. To meet the above demands, this paper has been designed and studied three-phase inverter power supply based on the design of single-phase inverter power supply. This will provide favorable conditions for three-phase high-performance inverter power matched by the generator.In this thesis, the inverter technology and the development of the inverter power are described firstly. The overall design program is determined according to the basic principles of three-phase inverter system. In the cases of hardware design, the voltage-type three-phase half-bridge inverter structure is chosen as the main circuit structure and Microchip's DSPIC30F4012 is chosen as the main chip. Then the article designs and researches inverter circuit, driver circuit, working power supply, voltage regulator feedback circuit protection circuit of three-phase inverter power. RCD snubber circuit is proposed to reduce the switching losses of IGBT. The software design parts are to compare the three-phase inverter control algorithms deeply and achieve the SPWM control by equal-area calculation method. In order to avoid the dead zone in the algorithm, a number of improvement works are done.The results are shown that the three-phase AC power output by inverter power presents stable waveform, same amplitude, equal frequency (50Hz), phase difference of 120°and less harmonic. Thus it has the ability to meet actual needs. What's more, the remaining loads can work normally in the case of load short phase. The load terminal voltage's waveform distorts less and the power has a strong ability of load balancing. The anti-jamming design of software and hardware makes the system stable. RCD snubber circuit is designed to solve the IGBT switching loss problem.