Microcontroller based fuzzy logic technique for dc-dc converter

This paper discuss the design and implementation of a microcontroller based fuzzy logic technique for dc-dc converters. An ldquoon-chiprdquo analog-to-digital (A/D) converter and a PWM generator eliminate the external components needed to perform these functions. Implementation issues include limited on-chip program memory, unsigned integer arithmetic, and computational delay. The duty cycle for the dc-dc converter can only be updated every eight switching cycles because of the time required for the A/D conversion and the control calculations. However, it is demonstrated here that stable responses can be obtained for both buck and boost converters under these conditions. Another important result is that the same microcontroller code, without any modifications, can control both converters because their behavior can be described by the same set of linguistic rules.