What is an EC motor and how does it work?

An EC motor is an electronically commutated motor - that is, a permanent-magnet synchronous motor whose operation is controlled by embedded electronics. It is these electronics that make the EC motor the foundation of energy-efficient ventilation.

An EC fan can operate on either an alternating current (AC) or a direct current (DC) power source. If AC is applied to the input, the control board first converts it to DC and then generates AC with the required frequency, which is set by the electronics itself. As a result, the speed is not tied to the mains frequency, and the motor operates just as stably at both 50 Hz and 60 Hz.

Structurally, an EC motor consists of three main components:

• A permanent magnet rotor - the rotating part that does not require a separate power supply;
• A stator with winding - the stationary part through which current flows;
• A control board - the “brain” of the motor, integrated directly into the casing.

The operating principle can be described as follows:

1. Power-either AC or DC is supplied to the fan;
2. The control board performs the necessary current conversions and supplies it to the stator windings;
3. The current flowing through the windings creates a magnetic field;
4. The magnetic field turns the permanent magnet rotor and the impeller rotates along with the rotor.

Since the switching timing is controlled by electronics rather than the mains frequency, the speed can be adjusted precisely and smoothly with no need for an external frequency converter. EC motors offer significant advantages over AC (asynchronous motors): lower energy consumption and higher efficiency, less heat generation, and built-in speed control.

Why EC fans are now a market necessity rather than a mere whim – this is a topic for a separate article, which you’ll be able to read in our upcoming publications.