Computer-aided design of PWM inverter drives using general purpose circuit analysis packages

Modeling techniques are presented which allow general-purpose circuit-analysis CAD (computer-aided design) packages to be modified and used for PWM (pulsewidth-modulated) inverter drive simulation. Circuit-equivalent PWM techniques which allow any PWM control strategy to be implemented in circuit-analysis CAD packages are presented. In addition, the details of circuit-equivalent motor models, based on two-axis theory, for transient motor performance simulation are presented. It is shown how these models can be simply interconnected to produce a complete-circuit-equivalent CAD simulation of the complete inverter-motor drive system. Typical examples, both computed and experimental, for various operational modes for both voltage-source-inverter and current-source-inverter PWM variable-speed drives are presented to confirm the validity and accuracy of the modeling techniques, and to demonstrate the advantages of the circuit-analysis CAD PWM drive package.<>