The Experiment Study Of A New Kind SVPWM Variable-frequency Method To Single-phase AC Machines

Single-phase AC machines, which consume a large amount of energy, are widely used in household electrical machines and other low-power situations. In response to the current energy crisis, the "speed-adjustment energy-saving" project is adopted in the industrial area. On the one hand, it can realize "energy-saving and consumption-reducing"; on the other hand, it can also improve the environment. For the energy-saving in the field of household electrical machines, the single-phase AC Machine Speed Control method comes into mind.Speeds in traditional single-phase AC machine are usually obtained using changing machine's terminal voltage or number of pole-pairs. With the development of the microprocessor and power electronic technology, people pay more attention on the application of frequency control to single-phase AC machine, and its application extension are also being observed.Nevertheless, there are still many problems, such as high switching energy loss due to high frequency of power electronic devices in VVVF, which possibly counteracts energy saved due to variable-speed operation. At present, one of the effective measurement to solve this problem is adopting Space Vector Pulse Width Modulation (SVPWM) technology. SVPWM technology has some merits such as low switching frequency and effective utilization of voltage. Therefore it has found widely application in the three-phase AC motor. Enough related research and application have been found on this aspect. However, only a few papers exist in the field using SVPWM technology in single-phase AC machines.Related technologies and methods of single-phase AC machine's VVVF have been studied in this paper. Beginning with the principle of single-phase machines by VVVF, this paper analyzes the inverter's topology of single-phase machines SVPWM technology. Then a new two-phase SVPWM method based on the two-phase-three-bridge inverter is put forward, which increases the DC voltage inverter utilization and also achieves energy-saving. In order to evaluate the method above, relevant hardware and software are designed based on TI's TMS320LF2407ADSP. Experimental results show effectiveness of this method.