Single-phase brushless DC motor overcomes a key impediment in AC to DC replacement by matching vibration and noise with three-phase BLDC.
Electric fans commonly use low-cost AC motors built around capacitors, which now increasingly demand replacement due to high power consumption. However, while three-phase brushless DC (BLDC) motors offer better durability, noise level and controllability, their prices are higher than those of AC motors.
Next, single-phase brushless DC motors, despite providing better cost and energy efficiency, have torques fluctuate widely while the motors are rotating. That, in turn, generates large vibration and noise. Nidec’s answer to this key impediment in AC to DC motor replacement: single-phase brushless DC motor that is lower in price than common AC motors and generates approximately the same amounts of noise and vibration.
In other words, the single-phase BLDC motor retains the high energy efficiency, controllability, and other advantages of conventional three-phase BLDC motors. So, it can be installed in household electric fans used in living rooms and bedrooms.
Source: Nidec Corp.
Brushless DC motor, a device that converts electricity to mechanical power, uses less energy than other motor types. In a brushless DC motor, electrical current is passed through coils that are arranged within a fixed magnetic field. The current generates magnetic fields in the coils, which causes the coil assembly to rotate.
Beyond electric fans, much development is underway to improve BLDC motor control systems in applications such as heating, ventilation, and air conditioning (HVAC), refrigeration, and robotics. For instance, new power ICs redefine BLDC motor control performance by optimizing power stage placement and reducing noise. Then there are advanced commutation algorithms that help improve control over the motor’s flux and torque over a wide speed range.
This article was originally published on EDN.
Majeed Ahmad, Editor-in-Chief of EDN and Planet Analog, has covered the electronics design industry for more than two decades.