STEADY-STATE MODEL OF THE AC/DC CONVERTER IN THE HARMONIC DOMAIN

A set of equations are developed that describe the 6-pulse convertor in the steady-state harmonic domain. The method used is to directly convolve in the harmonic domain the DC voltage in each conduction period, with an appropriate sampling function. This avoids the need to use transfer functions, FFTs, or complicated Fourier transforms. The technique is fast and simple, and is able to model effects that have, until now, been largely ignored (such as the DC-ripple effect on commutation duration). Moreover, the equations are suitable for inclusion in a Newton-type solution method, as the partial derivatives are easily obtained.