Abstract
In this paper, TMS320F2812 type DSP is utilized as the core of system control chip, according to the principle of variable voltage variable frequency (VVVF) and sine wave pulse width modulation technology(SPWM), thus the start accelerating of three-phase asynchronous motors is successfully achieved. In order to simplify the structure of the system and reduce the cost of the entire device, the main system circuit adopted the construction AC-DC-AC, constituting three-phase bridge rectifier by a power diode(SR) and three-phase inverter bridge by an insulated gate bipolar transistor(IGBT). By changing the output voltage and frequency of main circuit, the constant voltage frequency ratio control of three-phase asynchronous motor can be achieved. The experimental results verify the correctness and feasibility of the proposed scheme.