High-Speed Digital Control in a Switching-Synchronized Sampled-State Space for Variable Frequency Multi-Phase Buck Converters

This paper presents a new method for control-ling variable frequency, multi-phase buck converters. At the MHz-range switching frequency for each phase, cycle-by-cycle digital control of current and voltage results in a fast transient response to and fast settling from disturbances. A key challenge in adding phases or increasing frequency is maintaining the ability to measure voltage without interference from switching transients; cycle-by-cycle voltage averaging is fast and largely impervious to these effects. Additional benefits include ease of design and implementation. Theory and modeling are presented and results are demonstrated in simulation.