Polyphase series capacitor DC-DC converter and control method

Abstract

A multi-phase series capacitor DC-DC converter, comprising: a power stage circuit for converting an input DC voltage into a stable DC voltage required by a load, wherein the power stage circuit includes at least two-phase inductors, and a difference between the inductor currents of each phase is provided. There is a phase difference with a preset interval between them, which is used to charge the load alternately in turn. A bidirectional switch is provided between each adjacent two-phase inductance. When the bidirectional switch is turned on, the corresponding two-phase inductance simultaneously charges the load. Charging; the load transient response circuit is used to control at least one bidirectional switch to conduct when a load transient forward jump occurs, so that at least two-phase inductors can charge the load at the same time, so as to quickly respond to the transient change of the load. The present disclosure also provides a control method of the converter, which can realize fast response to load transient changes.

Description

technical field [0001] The present disclosure relates to the field of electronic technology, and in particular, to a multi-phase series capacitor DC-DC converter and a control method. Background technique [0002] Existing multiphase series capacitor DC-DC converters are usually optimized for the control loop to improve the load transient response speed, but the load transient response speed is still limited by the rising slope of the inductor current. The traditional transient enhancement technology improves the rising slope of the inductor current by increasing the switching frequency. However, the increase of the switching frequency further compresses the on-time of the power tube, which poses a very high challenge to the design of the control and drive circuits; the increase of the switching frequency greatly increases. The switching loss of the power tube deteriorates the conversion efficiency. In order to avoid the overlap of the on-time of the multi-phase power tubes...

AI Technical Summary

Problems solved by technology

The traditional transient enhancement technology increases the rising slope of the inductor current by increasing the switching frequency. However, the increase in the switching frequency further compresses the conduction time of the power transistor, which poses a very high challenge to the design of the control and drive circuits; the increase in the switching frequency greatly increases the The switching loss of the power tube deteriorates the conversion efficiency

In order to avoid overlapping conduction times of multi-phase power tubes, the power tube control signals need to maintain a fixed phase difference of 360° / N, and the N-phase inductor current cannot be used to charge the load at the same time, and the load transient response speed is limited.

Images