Adaptive PWM Controller for Fan Motor Waveform Optimization

The patent changes the control parameter from fixed physical HALL sensor location to dynamically adjustable PWM switching timing parameters. The controller modifies the ON and OFF timing points of the PWM signal based on detected motor speed and period, allowing optimization of the motor driving current waveform without physical sensor repositioning. This resolves the contradiction by enabling waveform optimization through software parameter adjustment rather than time-consuming physical fine-tuning for each fan.

The patent replaces the hardware circuitry adjustment approach with a firmware-based PWM signal generation system. Instead of modifying hardware circuits for different fan characteristics, the controller uses firmware to dynamically calculate and adjust the PWM switching timing based on motor speed and period detection. This substitution eliminates the need for hardware modifications while maintaining waveform optimization capability, resolving the contradiction between waveform quality and ease of manufacture.

The patent implements dynamic adjustment of both the ON time and OFF time of the PWM driving signal based on real-time motor speed and period detection. Rather than statically advancing only the OFF time, the system dynamically coordinates both switching events to maintain waveform balance. The controller calculates appropriate timing adjustments that preserve current waveform symmetry while achieving optimization, resolving the contradiction between waveform adjustability and balance stability.

The patent transforms the fixed HALL sensor location control system into a dynamic control system that adapts to different operating speeds. The firmware detects motor speed and period, then dynamically adjusts PWM switching timing parameters accordingly. At low speeds, the system automatically modifies the timing to prevent excessive current and maintain efficiency, while preserving the simplicity of the physical sensor placement. This resolves the contradiction by adding computational adaptability without increasing physical system complexity.