In my thesis I designed a three-phase voltage source inverter for adjustable speed asynchronous motor drive with V-f control. The speed variation of an induction motor can be achieved by varying the frequency. To hold constant flux in the motor the voltage must be change linearly with the frequency, this is the so called V-f or scalar control. This is suitable for those applications, where the precise speed control is not required.
In the first chapter I introduce the simulations, which was the base of the selection of the semiconductors in the three phase bridge.
In the next chapter I write about the procedure of the designing of the hardware. I designed two PCB, one for the main curcuit and another one for the controlling. The controller of the inverter is a TMS320f28027 digital signal processor (dsp) from Texas Instruments.
After that I introduce the controlling software with examples from the source code. The software capable to change the modulation method of the PWM signals, therefore some improvemenets can be achieved.
Finally I built the inverter and made measurements. In the last chapter I present the results of this measurements.