Computer-aided design of PWM controlled power electronic systems using general purpose circuit analysis packages

Computer-aided design (CAD) techniques are presented which address the general problem of including complex pulse-width modulated (PWM) control strategies into power-electronic system simulations, using circuit-analysis CAD packages. Circuit-equivalent PWM techniques which allow any of the currently available PWM control strategies-natural-sampled, regularly-sampled, harmonic elimination, and optimized PWM-to be implemented in circuit-analysis CAD packages are presented. This CAD package allows complex open-loop and closed-loop PWM control schemes to be simulated for virtually any practical power-electronic system, including uninterruptible power supplies, static frequency changers, and variable-speed drives. Power-electronic system simulation examples and results are presented which demonstrate the ease of simulation using the PWM CAD package, together with comparative experimental results obtained from a microprocessor-controlled PWM inverter system.<>