EC fan overview: What is an EC fan?

EC stands for Electronically Commutated, which combines AC and DC voltages to achieve a perfect phase change between the two voltages.

The motor runs on DC voltage and can be powered by either a single-phase 230VAC or three-phase 380VAC supply. The motor contains the voltage conversion control circuit inside the motor.

The non-rotating part of the motor (stator) is extended to make room for the electrical circuit board, which includes the AC to DC power conversion as well as the controller.

Our EC motor (electronically commutated) is a Hall-less three-phase permanent magnet synchronous external rotor type motor (PMSM for short). In the commutation circuit, the AC voltage is converted to DC voltage by the commutator.

The motor position depends on the voltage provided through the inverter module (similar to the principle of frequency converters).

EC circuit boards differ from frequency converters in that they decide how to provide current (commutation) to the motor phases in the stator based on position, direction of rotation and default values.

EC external rotor motor structure diagram

The permanent magnets in the rotor generate the magnetic field required for full load operation. This allows high efficiency, low noise and continuous motor speed control. The mounting flange on the rotor is used for impeller assembly. Depending on the motor type, the terminal box is equipped with a cable screw connection or a connecting cable to facilitate quick connection. Depending on the application area, additional control functions (such as constant pressure control, volume flow control, temperature control) can be adopted.

Conventional DC motors have a housing that contains all components such as carbon brushes, commutator, bearings, armature with windings, etc. They are arranged one after another. With EC motor components, more space is saved, and collectors and carbon brushes are not required. As a result, the motor is significantly shorter and therefore has advantages in terms of size and quiet operation during installation.

Compared with conventional motors, the investment cost of EC fans is slightly higher, but due to low energy consumption and low installation costs (no transformer control, frequency converter or phase angle control is required), they can mostly be amortized in the shortest operating time.

Under the current environmental requirements of carbon peak, our domestic motor and fan manufacturers are constantly rising and making real contributions to the beautiful future of green waters and green mountains around the world!