The SVPWM Method Hits The Target In The AC Invert Air-conditioner's Application And Research

In this paper, the method of AC motor speed regulation was discussed and the application of variable-frequency-speed-regulation technology in home invert air-conditioner was displayed. With advantages such as higher usage of DC voltage, adapt to digital-control, the capacity of building high performance speed regulation system, et al., Space-Vector-Pulse-Width-Modulation(SVPWM) is a better method than Sinusoidal Pulse Width Modulation in field of AC motor speed regulation. Under the light of simulating AC ansynchronization-motor as DC motor, frequency conversion technology with vector-control depends on completely research of ansynchronization-motor's mathematic model. So, the ansynchronization-motor's mathematic model was analyzed and the model was treated with orthogonal transform. From the transform, a new mathematic model in 2-phase-rotation-coordinates with synchronous speed appears and the stator current is synthesized by two components: one is the torque component, and the other is the flux component. By controlling the two current, AC motor can be controlled like a DC machine which torque and field can be adjusted respectively.In this paper, a inbuilt system was investigated and analyzed to realize the SVPWM slid frequency system, as while as the voltage-vector-output-configuration of the inverter and the Space Vector Modulation(SVM) scheme and the measurements of rotor-flux were studied. The system hardwares, including control/drive board and current detective circuitry and so on, were researched. The system software which makes up of vector transforming, SVM, PWM wave output, current detecting, environment temperature detecting, coil temperature detecting, compressor temperature detecing was designed, too.Software was debugged and emulated by using the tools and software that Fujitsu Company provided. Fujitsu's software—Softune V3 can compile and link the C language program, and it also can find the errors of sourse program conveniently. It can emulate the sourse program without connecting the hardware, so it is easy to develop software program. Conneted hardware tools and target board, we can do hardware debugging. We can see the variable's value on time in debugging.Experiments were given to test the research. The results of experiments indicated that the scheme of hardwares and softwares were feasible and the SVPWM speed-regulation-system could work normally under the given load. The output waves of voltage, currents and speed curve were coincident with the expectable one.On the basis of this paper, the system software and hardware also can be improved. In order to decrease the harmonics components, the PWM carrier frequency should be increased. At the same time, by researching a better control method and combining a better cooling system, the inverter air conditioner's capability will be enhanced greatly.