Brushless DC Motor Model and Its PIC Control Algorithm Implementation

This article presents a brushless DC motor model integrated with a PIC microcontroller-based control algorithm, designed to deepen understanding of brushless DC motor operational principles. We will elaborate on the model construction process, covering material selection criteria and circuit design methodologies. The implementation incorporates PWM signal generation for commutation control and Hall sensor feedback processing through PIC's built-in capture/compare modules. For practical control applications, we detail the PIC control algorithm's architecture, including position sensing via back-EMF zero-crossing detection and six-step commutation logic implemented in C code. The algorithm utilizes PIC's peripheral pin select (PPS) feature for flexible pin mapping and timer interrupts for precise timing control. Practical examples demonstrate algorithm implementation with code snippets showing initialization routines for ADC conversion (current sensing) and complementary PWM output configuration. Finally, we explore the model's evolution potential, discussing enhancements like sensorless control using advanced position estimation algorithms and field-oriented control (FOC) implementation for improved torque efficiency.