Hysteresis control of a continuous boost regulator

To comply with forthcoming mains harmonic distortion regulations, electronic equipment will require pre-regulators. For high voltage applications, where the DC output exceeds the peak mains supply voltage, the preferred option is a boost converter. The merits of continuous and discontinuous operation are discussed with reference to optimum solutions. The conventional control technique, average current mode control, shows instabilities under certain conditions. An alternative control technique, hysteresis control, is proposed and analysed. This technique is believed to exhibit greater stability. Four hysteresis control algorithms are presented. Practical implementations of these techniques are shown, together with a comparison of the measured circuit performance