A variable frequency resonant commutated converter

A novel DC link power converter utilizing resonant commutation is presented. Since resonant commutation is accomplished, the power converter switches are SCRs with lower costs than forced commutated devices. The focus of this paper is on the variable frequency operation of the power converter with potential application in variable frequency custom power delivery or adjustable speed motor drives. The converter operates with greater stored energy in the DC link thus offering current holdup capabilities during a contingency which cannot be attained with a conventional resonant DC link power converter and achieves minimum switching losses without increased conduction losses. Harmonic elimination is achieved by employing sinusoidal pulse width modulation (SPWM) control of the power converter. Simulation results and experimental validation of the resonant commutation of a laboratory model are discussed