A fast algorithm for software implementation of state-space control of DC-DC converters

This paper demonstrates the use of state-space based control method as an enabler for Software-Intensive Control of dc/dc converters, with a worked example for a boost converter. The entire process flow is software controlled: design, optimization, and implementation. Despite having the theory of state-space control known for over 20 years, the power supply industry seemed to avoid its use due to complexity of mathematic apparatus and implementation. A novel algorithm is proposed within this paper to allow running the microcontroller code at higher frequency rates. The control software yields very simple and it is demonstrated to be implementable on any general use microcontroller, with generic software functions from C-language or assembly libraries. Snippets of software routines are provided for a Microchip platform to illustrate their simplicity. Execution time is compared with previous solutions to demonstrate this as possibly the fastest algorithm, at around 4 μsec or 250 kHz, for control including current estimation, run on a general use processor without dedicated digital hardware controller. Optimization of code and design are followed up with MATLAB and Microchip microcontroller example details.