Transputer-based harmonic-elimination PWM control of inverter drives

Harmonic elimination PWM strategies for voltage source inverter and current source inverter (VSI and CSI) drives have been developed using modified regular sampling techniques. These strategies can be generated online in real time using a simple microprocessor software algorithm and can be used over the complete voltage/frequency range of the drive up to and including the transition from PWM to quasi-square wave (QSW) operation. The implementation and generation of these techniques using the parallel processing INMOS transputer are discussed, and the concurrency programming ability of the transputer for PWM generation is emphasized. The implementation of the new PWM strategy can also be performed on any standard 8 or 16 b microprocessor using 4 or 1 timer implementations. Results from an experimental transputer-controlled PWM inverter drive are presented to demonstrate and confirm the special features of the new regular sampled harmonic elimination PWM control strategies