A 3-phase BLDC motor drive reference design with Field Oriented Control (FOC) sensorless mode specifically for ceiling fan applications, supporting power up to 50 W.
A Brushless DC (BLDC) fan controller is essential for improved energy efficiency, reducing power consumption and lowering electricity costs. It enables precise speed control, allowing users to adjust fan speeds according to their specific needs and preferences. BLDC fans operate silently due to their brushless design, ensuring a noise-free environment. With a longer lifespan than traditional fans, BLDC fan controllers offer durability and reduced maintenance requirements. To address the issues, STMicroelectronics have launched a 3-phase BLDC motor drive up to 50 W, STEVAL-IHM038V1 reference design suitable for fan controllers. The design uses Field Oriented Control (FOC) sensorless mode, specifically designed for ceiling fan applications.
The design is based on a 32-bit ARM Cortex M3 core microcontroller STM32F100C6T6B. The solution integrates a comprehensive inverter stage and control stage, enabling the drive of a 3-phase BLDC fan motor in the power range of 30-35 W. A passive PFC (Power Factor Correction) stage is incorporated for power factor correction, ensuring a power factor of up to 0.90, meeting the minimum recommended requirement for ceiling fan applications. The design supports a maximum input voltage of 265 V AC or 375 V DC and a minimum input voltage of 90 V AC or 128 V DC. The applied motor can handle a maximum continuous output power of up to 50 W.
A passive power factor correction (PFC) circuit is implemented, utilizing a standard Valley fill design for improved power factor by reducing ripple current. The compact design uses an auxiliary power supply of +15 V. An infrared (IR) receiver/demodulator is onboard, allowing speed and on/off control via an IR remote. The system includes hardware protection for overcurrent situations and overtemperature protection using an NTC thermistor. The reference design also incorporates Overvoltage and Undervoltage detection mechanisms for enhanced safety and performance. The system comprises four main blocks: control block, power block, motor and power supply block. The Printed Circuit Board (PCB) size of the design is tailored to fit perfectly within the form factor of a ceiling fan.
STMicroelectronics has tested this reference design. It comes with a Bill of Material (BOM), schematics, PCB layout, etc. You can find additional data about the reference design on the company’s website. To read more about this reference design, click here.