Co-projeto de perspectiva completa para conversores CC-CC com controlador digital

Abstract

Cyber-physical systems performance are dependents of cyber and physical domains. This work applied a cyber-physical approach in digitally controlled power converter. This thesis proposes a new full perspective co-design methodology, incorporating into a single co-design the multidisciplinary steps of electronics, control and computing. In order to develop this methodology is presented an analysis of the co- design stages interdependencies. Which shows some dependencies such as AD converter resolution, DPWM module resolution, converter switching frequency, controller sampling frequency, control algorithm execution time, system dynamic response, inductive and capacitive components. This thesis proposes a new microcontroller test algorithm to estimate the worst-case execution time of digital controller algorithm. Besides that, the ADC and DPWM characteristics is analyzed. The design methodology of converter inductance associates the plant characteristics to facilitate digital controller design. The switching and sampling frequency co-design approach takes into account the closed-loop system dynamic response, the quantizers, the digital controller execution time, and the output voltage ripple. A laboratory prototype is built in order to validate the proposal design methodology. The topology employed is a DC-DC buck converter operating in continuous conduction mode. The mathematical analysis and practical results shown the importance of multiple perspectives co-design. Being that only one of the three computational platforms compared was able to perform the digital controller correctly. Moreover, the small number of parameters forced by the designer reduced the impact of arbitrary choices that exist in traditional design methodologies.