Frequency & duty cycle control considerations for soft-switching buck chopper

This paper presents considerations on the switching frequency and duty cycle and operating equations of soft-switching BUCK chopper. These considerations are discussed and applied to selected soft-switching families such as ZVS-QRC, ZCS-QRC, ZVS-QSW-CV, ZCS-QSWCC, ZVT-PWM and ZCT-PWM [1]. The limitations on switching frequency and duty cycle are derived in terms of. chopper input voltage (V-g), chopper output current (I-F), resonant elements values including (C-n L-r), voltage and current of: filter capacitor and reactor or initial values of capacitor and reactor (V-I,V- (I)).