This application note describes a low-cost PMAC motor drive system using the ST7FLITE35 microcontroller and STS8C5H30L complementary MOSFETs. It is suitable for PMAC motors up to 12V-50W. The document provides reference schematics, firmware library, and convenient functions for sinusoidal waveform generation, synchronization mechanism, and closed-loop control of PMAC motors.
The document details a low-voltage single-sensor three-phase AC permanent magnet (PMAC) or brushless AC (BLAC) control system. It focuses on achieving high efficiency, power density, and silent operation by synchronizing excitation with rotor motion using direct feedback of the angular position.
The solution is implemented on the ST7FLITE35 microcontroller, utilizing its Lite Timer to measure Hall sensor signals for synchronization and a 12-bit autoreload timer in PWM mode to generate sinusoidal waveforms. The note provides reference schematics suitable for motors up to 50W at 12V, firmware library details, and guidance on configuring parameters for initial operation.
The reference schematics can be used for PMAC motors up to 12V and 50W.
The system supports the usage of only one sensor to detect rotor angular position.
PMAC motors are designed to be excited with a sinusoidal current waveform.