A simplified approach to implementation of state-space control of DC/DC converters on low-cost microcontrollers

The recent emergence of microcontroller platforms for digital control of DC/DC converters requires the deployment of modern control algorithms. State-space based control methods are usually involving complex analytical development and are not easily adopted by industry. This paper proposes a simplified arrangement of control equations and software in order to facilitate the understanding of state-space based control and its implementation on existing low-cost microcontrollers. The control law is herein separated into two terms only: a conventional PI controller module and a "compensation" module expressed as a 4-term sum-of-products, each product being made up with a pair of an offline pre-calculated constant and a measurement sample. Both terms are coded in assembly language for faster calling from a master C program. Several options for current´s estimation are discussed under this software arrangement.