A Suppressed Noise Dc-Dc Buck Converter Introducing A Novel Modulation Scheme with Random Pulse Sequence

This paper describes a dc-dc buck converter that can suppress switching noise. Nowadays, switching power supplies are widely used as power supplies. However, the switching noise generated by the power supply may adversely affect other equipment, and countermeasures are required. Currently, PWM method is widely used to control the switch devices of the switching power supply, but when this switch control method is used, large switching noise occurs. In the case that delta-sigma modulation measure is used for switch control of power inverters, no large switching noise component is generated. However, when this method is used for dc-dc converter, large switching noise components are generated like PWM method. In order to solve this problem, this paper proposes a switch control method that introduces delta-sigma modulation technique with a random pulse sequence. The proposed control method is applied to dc-dc buck converter and confirmed the noise suppression effect. Moreover, the switching number of the proposed dc-dc converter can be small and the switching loss becomes low.