Study of Buck Converter under Supply Voltage Variations

In the presented work, the influence of the supply voltage variations of the electric transport contact networks on the operation of a buck converter in different control algorithms is researched. The studies were performed at constant frequency and pulse width modulation (PWM) and at variable frequency, as well as at constant pulse duration in “ON” state. The results of the study confirm the advantage of control of buck converter with variable frequency at lower supply voltages. The current pulsation for the example is approximately twice as small with variable frequency control.