Dsp-based Direct Torque Control System Study

Direct Torque Control (DTC) technology is a high-performance adjustable speed method with fast torque response, which has many advantages such as simple structure and excellent dynamic and static performance etc. With the development of Power Electronics, specific integrated chips and Control Theory, applying new motion control algorithm and developing full digital control system have become mainstream research. TI 2000 series' DSP, which integrates numerous on-chipped memories and peripheral circuits used for motion control, has been widely used in motion control industry.After the analysis of traditional DTC , this paper concludes characters of direct torque control. Also this thesis expatiates many basic conception of DTC in detail, which include the calculation of flux and torque,hysteresis control of flux and torque,PWM generation and PWM control.According to Sensor-less direct torque control system, this paper constructs the adjustable model by useing the conventional current difference. The speed identification scheme based on model for whole-speed range is adopted with the method of model reference adaptive system. The simulation result is analyzed and summarized, which shows that the speed identification scheme is valid.Finally, this thesis selects three-phase induction motor as object of control. The hardware platform of direct torque control system is constructed for experiment studies, which is based on high-speed digital signal processor (DSP) TMS320F2812 DSP as the controller and intelligent power module (IPM) as the main devices. This thesis explains the realization of hardware control circuit in detail and the corresponding control system software compiling method. The full digital control of direct torque control system was established.