| Abstract |
A signal processor based high power drive system with three-level voltage source inverter feeding an induction machine is presented. In order to achieve quick response of the complete drive system, an advanced field-oriented control technique with novel flux-calculator is employed. Precontrol networks for stator current and rotor flux regulation contributes to an excellent dynamic behaviour. To attain the megawatt range, a gate-turn-off thyristor (GTO) equipped three-level inverter is used. A new pulse width modulation (PWM) method enables high quality realization of voltages as well as high dynamic performance. The novel inverter trigger set, developed from two-level inverter control, performs an on-line calculation of three-level PWM waveforms. It effects voltage space vector approximation with optimal switching sequence of the inverters GTOs. Both, field-oriented control and generation of pulse-patterns are implemented on a digital signal processor (DSP). The necessary calculation time is short enough to enable additional tasks, e.g. identification, diagnostics, communication, etc. |
