The terms of the classification of the motor

1. Shaded pole motor

It is a kind of single-phase AC motor, usually using cast aluminum rotor with cage chute. According to the different shape and structure of the stator, it is divided into salient pole shaded pole motor and hidden pole shaded pole motor.

2. Universal motor

An electromagnet excitation beam type DC motor that generates excitation beam through an electromagnet, in which the excitation winding and the armature winding are in series.

This characteristic is that the rotation speed will change drastically with the change of load. When starting or at low speed, a large torque will occur. When the load decreases, the rotation speed will increase.

This characteristic is generally referred to as the series excitation characteristic. It was mainly used for specific purposes such as trams and elevators. It has now been replaced by a variable speed control method for induction motors and synchronous motors using frequency converters.

This type of motor can also be used with AC. However, if a motor designed as a DC motor is used with AC, the loss such as iron loss will increase, so it will generate abnormal heat.

3. Stepper motor

Stepper motor is an open-loop control motor that converts electrical pulse signals into angular displacement or linear displacement. It is an induction motor.

Stepper motors can be easily controlled by digital signals. In addition to industrial applications and computer peripherals, they are also used in office equipment such as fax machines and copiers. Stepper motors are generally divided into HB hybrid stepper motors and PM type stepper motors.

4. AC servor motor

Motors that work with AC power are called AC motors, and AC servor motors are divided into induction motors and brushless DC motors. The brushless DC motor is called an AC motor mainly because an alternating voltage with voltage variation is applied to the coil of the rotating brushless DC motor.

5. PM motor

Motors using permanent magnets, which are divided into brushed DC motors and brushless DC motors.

6. Brushless DC motor

Brushless DC motor overcomes the shortcomings of brush DC motor of brush wear and electrical interference by removing the brush. It has the characteristics of maintenance-free, miniaturization, high motor efficiency and good heat dissipation performance. It is also called commutatorless motor and brushless motor.

The terms of characteristics of the motor

1. Holding torque

When the stepper motor is stopped in the energized state, even if an external force is applied, due to the attractive force between the rotor and the stator, the stop position can still be maintained. This torque that can resist the external force is called the holding torque.

2. Stop torque

When the PM type and HB type stepper motor is not energized, it also has a certain degree of holding torque under the effect of the attraction of the rotor magnet, which is called the stop torque

3. Pulse frequency

The speed of a stepper motor is generally expressed in pulses per second (steps) [pps]. Also called pulse rate or step rate.

4. surge

Refers to the working interval where the fan air volume is periodically in an unstable state. Noise will also increase, so choose a fan that will not surge is needed.

5. Pole number

The so-called pole number or pole refers to the number of magnetic poles appearing on the face after the motor is cut in a direction perpendicular to the axis.

Basically, the number of poles is even (2,4,6,8 ...), and the winding method is divided into distributed winding and centralized winding. The centralized winding is suitable for brushless motors, and the number of poles can be easily changed according to the wiring of the coil. For 6-coil stators, 2-pole, 4-pole or 8-pole wiring can be performed. But the motor that has been completed cannot change the number of poles to 4 or 8 poles. In the 9-slot rotor, 12-pole distributed winding is mostly used, which is suitable for induction motors, and the number of poles must be determined before winding.

Before the advent of 2-pole brushless motors running at high speeds of 50 or 60 revolutions per second, small motors were mostly 4-poles, and their wiring was complicated. It was difficult to call them distributed windings or centralized windings. Induction motor poles can be changed by changing the wiring This is a technology that changes the synchronization speed to achieve dual speed operation.

6. Protection level

According to the structure of the motor housing, the protection methods are divided into the following types.
-Open type: unprotected structure
-Protection type: The housing has an opening, and the external air around the motor can circulate with the internal structure (IP2X)
-Fully enclosed type: the housing is closed to prevent external air around the motor from entering the motor (IP4X)
-Drip-proof type: A structure with waterproof protection (IPX2)
-Drip-proof protection type: a structure that satisfies both the protection type and the drip-proof type (IP22)
-Fully enclosed external fan type: Fully enclosed type with fan. Structure for cooling the shell surface
-Fully closed self-cooling type: fully closed type without fan. Natural cooling method
-Fully enclosed external force ventilation type: Fully enclosed type without fan, the external air has a fixed air flow, which has the same cooling function as the external fan
-Explosion-proof type: It can be used normally in places with explosive gas. Divided into safety enhanced explosion-proof type, pressure-proof explosion-proof type, etc.
-Indoor type: the type used in the house
-Outdoor type: The type that can be used outdoors even after the sealing material is installed

The terms of structure of the motor

1. Coil

In a motor, a wire is generally wring on a magnetic pole and is called a coil, and each coil is connected to each other to form a winding.

2. Rotor

The rotating part. Also called the rotor.

3. Iron core

The so-called iron core is a magnetic channel. As the literal meaning is, the material is iron and silicon is added, commonly known as silicon steel. In addition, iron that combines two magnets with magnetic flux is generally called a yoke.

In the motor, the iron core is divided into a stator iron core and a rotor iron core, and the magnetic circuit is formed by the gap between the two.

The magnetic poles of the stator core that constitutes the excitation circuit of the electromagnet excitation type DC motor are excited by direct current. Therefore, the iron core does not need to have a laminated structure, and soft steel can be used.

On the other hand, the magnetic flux of the rotor core constituting the armature circuit changes when it rotates. Therefore, a laminated core is used, and the magnetic pole of a small DC motor generally uses a permanent magnet.

Since the excitation is performed by AC, the stator core of the synchronous motor, the stator of the induction motor and the iron core of the rotor are preferably laminated iron cores.

4. Shaft

Refers to “the output shaft”.

5. Bearing

Bearings can be used to reduce wear on rotating parts.

The terms of evaluating the motor

1. Motor efficiency

The efficiency of a motor in converting electricity into power refers to the ratio of mechanical output to input power expressed as a percentage.

2. N-T characteristics

The motor characteristic diagram showing the relationship between the rotation speed and torque is also called "TN characteristic" and "NT characteristic". Together with the TI characteristic diagram showing the relationship between torque and motor current, it is collectively called the TI-TN characteristic diagram.

3. TI characteristics

The motor characteristic diagram showing the relationship between the torque and the motor current, together with the TN characteristic diagram showing the relationship between the torque and the rotation speed, is collectively called the TI-TN characteristic diagram.

4. TN characteristics

The motor characteristic diagram showing the relationship between the rotation speed and torque is also called "TN characteristic" and "NT characteristic". Together with the TI characteristic diagram showing the relationship between torque and motor current, it is collectively called the TI-TN characteristic diagram.

5. P-Q curve

The fan air volume-static pressure characteristic diagram (P-Q curve) is a curve that represents the relationship between the air volume and the static pressure caused by the loss of pressure acting on the air inlet and air outlet. When the loss due to pressure (static pressure) is 0, it is called the maximum air volume, and when the pressure loss (static pressure) is maximum, it is called the maximum static pressure.