electric motor manufacturing

Three Phase Motor

Complete product specifications, quality assurance


What is a Three-Phase Motor?

Three-phase motors are a type of AC motor that is a specific example of a polyphase motor. These motors can be either an induction motor (also called an asynchronous motor) or synchronous motor.

The motors consist of three main components – the stator, the rotor, and the enclosure. The stator consists of a series of alloy steel laminations wound with wire to form induction coils, one coil for each phase of the electrical power source. The stator coils are energized from the three-phase power source.The rotor also contains induction coils and metal bars connected to form a circuit. The rotor surrounds the motor shaft and is the motor component that rotates to produce the mechanical energy output of the motor.

The enclosure of the motor holds the rotor with its motor shaft on a set of bearings to reduce the friction of the rotating shaft. The section has end caps that hold the bearing mounts and house a fan that is attached to the motor shaft, which spins as the motor shaft turns.

The spinning fan draws ambient air from outside the enclosure. It forces the air across the stator and rotor to cool the motor components and dissipate heat that is generated in the various coils from the coil resistance.


Types of Three-Phase Motors

There are three main types of 3-phase motors

Squirrel Cage Motor

The construction is simple and rugged and consists of a cylindrical laminated core rotor with slots on the external periphery. The structure of this rotor assembly resembles the shape of a squirrel cage. The squirrel cage has rotor bars instead of the expected rotor windings. This motor does not use slip rings or brushes, making construction more straightforward and robust.

Wound Rotor Motors

The stator on a wound rotor motor is similar to that of the squirrel cage motor, but the rotor is built differently. The rotor is built to include slip rings and brushes that conduct the electricity to the rotor since the rotor in a wound rotor motor is insulated. The purpose of slip rings is to create resistance in series with the rotor windings while the motor is starting. This helps to reduce the current draw of the motor on start-up.

Synchronous Motor

Synchronous motors need a secondary DC power supply in order to feed and magnetize the rotor, the DC current is fed to the motor through the use of split rings. Permanent magnets can be used on the rotor as well. Since the motor needs to be operating at synchronous speed to work, a starting mechanism is usually necessary to spin the motor at or near operating speed before the motor can operate properly.


Advantages of 3-phase motors


It has simple and rugged construction.


It requires less maintenance.


It has high efficiency and good power factor.


It has self-starting torque.

working principle

How does a 3-Phase Motor Work?

we produces

Popular products

EPT is an electric motor manufacturer that offers many different three-phase and single-phase motors; Our electric motor factory is in China. We are making the three-phase motor with a cast iron body and an Aluminium body for IE1, IE2, and IE3 standards. The three-phase motors with cast iron bodies are special for heavy-duty industry machines, water pumps, etc.

IE1 basic standard motor

It has the characteristics of high efficiency, energy saving, high starting torque, low noise, low vibration, and easy maintenance;

IE2 high-efficiency motor

IE2 series motors can be widely used for driving equipment of various types of machinery, such as machine tools, blowers, pumps, compressors, Packing machinery, mine machinery, and construction machinery.

IE3 super-high efficiency motor

The product is used in various fields of the national economy, such as machine tools, pumps, fans, and compressors; it also applies to transport, stirring, printing, agricultural machinery, and other types of food that do not contain flammable, explosive, I’ve or corrosive gas applications.

related information

Industry News

These two situations are involved for the three-phase asynchronous motor, regardless of its rotor design, stator manufacturing, or rotor manufacturing. When a single delta connection is used, the three-phase asynchronous motor can still start generally in the case of phase loss. However, under the long-term operation of the rotor of the three-phase asynchronous motor, if there is no starting torque, the starting current will increase, and the grid’s voltage will decrease. Happening. For a three-phase asynchronous motor with a delta connection, the line voltage is three times the root of the phase voltage, and if it is a star connection, it is three times the root of the phase voltage.
What are the three-phase asynchronous motor starting methods?

The basic idea behind how electric motors work is simple: the rotor spins inside a stator that is connected to an electrical supply. The rotor rotates when an electromagnetic field produces attractive and repulsive forces. When the rotor turns faster than the magnetic field, it recharges the battery and acts as an alternator. Coils of wire connect the rotor and electromagnets in an electric motor. When power is applied to a coil, the coils of wire turn into an electromagnet. This electromagnet attracts the opposite pole of the magnet. The current is then switched from one bar to the other by changing the polarity of the commutator. The physical principle of electric motors is the same for both DC and alternating current (AC) motors.

How electric motors work?

A three-phase asynchronous motor is a component of the engine. Aging, dampness, heat, erosion, foreign matter intrusion, and impact from external forces will cause damage to the three-phase asynchronous motor. Motor overload, Undervoltage, overvoltage, and lack of phase operation can also cause damage to the three-phase asynchronous motor. The three-phase asynchronous motor is faulty. Three-phase asynchronous motor faults are generally divided into three-phase asynchronous motor grounding, short circuit, open circuit, and wiring errors. The grounding of the three-phase asynchronous motor refers to the grounding caused by the insulation damage between the three-phase asynchronous motor and the iron core or the casing.

What are the faults of three-phase asynchronous motors?

Operating conditions

Y2/Y3 Series Three-Phase Asynchronous Motor

Ambient temperature


Rated voltage

380V or any voltage between 220-760V

Rated frequency


YE3/YX3 Series Three-Phase Asynchronous Motor

Protection class


Insulation class



Star-connection for up to 3kw,

MS Series Three-Phase Asynchronous Motor

Rated voltage


Protection class


Insulation class

Class B/F

YDT Series Three-Phase Consequent-Poles Asynchronous Motor

Rated frenquency


Rated voltage




YT Series Three-Phase Asynchronous Motor

Rated voltage

380V or any voltage between 220-760V

Protection class


Insulation class


Contact us to customize your three-phase motor

We provide a Wholesale 3-phase induction motor widely used in air compressors, washing machines, water pumps, fans, the mechanical industry, reducers, and hosts. The products sell well all over the country and are exported to Southeast Asia, Germany, Italy, Poland, Britain, France, the Middle East, South America, Africa, Asia, etc. More than 80 countries and regions.