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High Torque Direct Drive Permanent Magnet Motor Low Speed
High Torque Direct Drive Permanent Magnet Motor Low Speed
Specifications
Brand Name :
ENNENG
Model Number :
PMM
Certification :
CE,UL
Place of Origin :
China
MOQ :
1 set
Price :
USD 500-5000/set
Payment Terms :
L/C, T/T
Supply Ability :
20000 sets/year
Delivery Time :
15-120 days
Packaging Details :
seaworthy packing
Name :
Low Speed High Torque Direct Drive Permanent Magnet Motor
Current :
AC
Material :
Rare Earth NdFeB
Power Range :
15-3000kw
Work Mode :
S1
Cooling :
air cooling, liquid cooling, natural cooling
Poles :
2, 4, 6, 8, 10, etc.
Protection Grade :
IP23, IP54, IP55, IP68
Power :
5-3000kw
Efficiency Grade :
IE4, IE5
Description

Low Speed High Torque Direct Drive Permanent Magnet Motor

Energy Efficiency Standards
comply with GB30253-1 grade
Work Mode
S1
Altitude
below 1000m
Environmental Temperature
-15～+40℃
Installation Dimensions
comply with IEC standard
Control Mode
variable frequency vector control
Power Range
15〜3000kw
Install Type
IMB3 IMB5 IMB35
Cooling Way
IC411 or IC416
Rated Efficiency
50,75,125,150Hz(customized as per requirement)
Insulation Class
F(H)
Optional Parts
Encoder, spiral transformer, PTC, PT100
Protection Grade
IP54(IP23 customizable)
Wiring Type
junction box (aviation plug can be customized as per requirement)
Installation
IMB3 IMB5 IMB35
Rated Voltage
380V±10%,660V±10%

Required Environment
below 1000m altitude
temperature -15〜45°C
relative humidity below 90%

What Is The Permanent Magnet Synchronous Motor?

The permanent magnet synchronous motors, like any rotating electric motor, consist of a rotor and a stator. The permanent magnet synchronous motor construction is similar to the basic synchronous motor, but the only difference is with the rotor. In this type of motor, the permanent magnets are mounted on the rotor and the rotor doesn’t have any field winding.

The permanent magnets are used to create field poles. The permanent magnets used in the PMSM are made up of samarium-cobalt and medium, iron, and boron because of their higher permeability. The most widely used permanent magnet is neodymium-boron-iron because of its effective cost and ease of availability.

Detailed pictures
High Torque Direct Drive Permanent Magnet Motor Low Speed
Working Principle:

The working of the permanent magnet synchronous motor is very simple, fast, and effective when compared to conventional motors. Its operation is based on the interaction of the rotating magnetic field of the stator with the constant magnetic field of the rotor. The permanent magnets are used as the rotor to create constant magnetic flux, operates and locks at synchronous speed. These types of motors are similar to brushless DC motors.

The phasor groups are formed by joining the windings of the stator with one another. These phasor groups are joined together to form different connections like a star, Delta, double, and single phases. To reduce harmonic voltages, the windings should be wound shortly with each other.

When the 3-phase AC supply is given to the stator, it creates a rotating magnetic field and the constant magnetic field is induced due to the permanent magnet of the rotor. This rotor operates in synchronism with the synchronous speed. The whole working of the PMSM depends on the air gap between the stator and rotor with no load.

If the air gap is large, then the windage losses of the motor will be reduced. The field poles created by the permanent magnet are salient. The permanent magnet synchronous motors are not self-starting motors. So, it is necessary to control the variable frequency of the stator electronically.

Back-emf waveform
High Torque Direct Drive Permanent Magnet Motor Low Speed

Back emf is short for back electromotive force but is also known as the counter-electromotive force. The back electromotive force is the voltage that occurs in electric motors when there is a relative motion between the stator windings and the rotor’s magnetic field. The geometric properties of the rotor will determine the shape of the back-emf waveform. These waveforms can be sinusoidal, trapezoidal, triangular, or something in between.

Both induction and PM machines generate back-emf waveforms. In an induction machine, the back-emf waveform will decay as the residual rotor field slowly decays because of the lack of a stator field. However, with a PM machine, the rotor generates its own magnetic field. Therefore, a voltage can be induced in the stator windings whenever the rotor is in motion. Back-emf voltage will rise linearly with speed and is a crucial factor in determining maximum operating speed.

High Torque Direct Drive Permanent Magnet Motor Low Speed

A PM motor can be separated into two main categories: surface permanent magnet motors (SPM) and interior permanent magnet motors (IPM). Neither motor design type contains rotor bars. Both types generate magnetic flux by the permanent magnets affixed to or inside of the rotor.

SPM motors have magnets affixed to the exterior of the rotor surface. Because of this mechanical mounting, their mechanical strength is weaker than that of IPM motors. The weakened mechanical strength limits the motor’s maximum safe mechanical speed. In addition, these motors exhibit very limited magnetic saliency (Ld ≈ Lq). Inductance values measured at the rotor terminals are consistent regardless of the rotor position. Because of the near unity saliency ratio, SPM motor designs rely significantly, if not completely, on the magnetic torque component to produce torque.

IPM motors have a permanent magnet embedded into the rotor itself. Unlike their SPM counterparts, the location of the permanent magnets makes IPM motors very mechanically sound, and suitable for operating at very high speeds. These motors also are defined by their relatively high magnetic saliency ratio (Lq > Ld). Due to their magnetic saliency, an IPM motor has the ability to generate torque by taking advantage of both the magnetic and reluctance torque components of the motor.

Self-sensing versus closed-loop operation

Recent advances in drive technology allow standard ac drives to “self-detect” and track the motor magnet position. A closed-loop system typically uses the z-pulse channel to optimize performance. Through certain routines, the drive knows the exact position of the motor magnet by tracking the A/B channels and correcting for errors with the z-channel. Knowing the exact position of the magnet allows for optimum torque production resulting in optimum efficiency.

What applications use PMSM motors?

‍

Industries that use PMSM motors include Metallurgical, Ceramic, Rubber, Petroleum, Textiles, and many others. PMSM motors can be designed to operate at synchronous speed from a supply of constant voltage and frequency as well as Variable Speed Drive (VSD) applications. Widely used in electric vehicles (EVs) due to high efficiency and power and torque densities, they are generally a superior choice in high torque applications such as mixers, grinders, pumps, fans, blowers, conveyors, and industrial applications where traditionally induction motors are found.

Permanent magnet synchronous motors with internal magnets: Maximum energy efficiency

The permanent magnet synchronous motor with internal magnets (IPMSM) is the ideal motor for traction applications where the maximum torque does not occur at maximum speed. This type of motor is used in applications that require high dynamics and overload capacity. And it is also the perfect choice if you want to operate fans or pumps in the IE4 and IE5 range. The high purchase costs are usually recouped through energy savings over the run time, provided that you operate it with the right variable frequency drive.

Our motor-mounted variable frequency drives use an integrated control strategy based on MTPA (Maximum Torque per Ampere). This allows you to operate your permanent magnet synchronous motors with maximum energy efficiency. The overload of 200 %, the excellent starting torque, and the extended speed control range also allow you to fully exploit the motor rating. For fast recovery of costs and the most efficient control processes.

Permanent magnet synchronous motors with external magnets for classic servo applications

Permanent magnet synchronous motors with external magnets (SPMSM) are ideal motors when you need high overloads and rapid acceleration, for example in classic servo applications. The elongated design also results in low mass inertia and can be optimally installed. However, one disadvantage of the system consisting of SPMSM and variable frequency drive is the costs associated with it, as expensive plug technology and high-quality encoders are often used.

Flux weakening/intensifying of PM motors

Flux in a permanent magnet motor is generated by the magnets. The flux field follows a certain path, which can be boosted or opposed. Boosting or intensifying the flux field will allow the motor to temporarily increase torque production. Opposing the flux field will negate the existing magnet field of the motor. The reduced magnet field will limit torque production, but reduce the back-emf voltage. The reduced back-emf voltage frees up the voltage to push the motor to operate at higher output speeds. Both types of operation require additional motor current. The direction of the motor current across the d-axis, provided by the motor controller, determines the desired effect.

Benefits of PMSM motors

‍

High efficiency

This is particularly true at lower speeds. The permanent magnet motor does not require current to be supplied to its rotor to generate the rotor field, therefore eliminating the rotor losses almost completely. When compared to induction or reluctance motors it also requires lower currents on the stator and has a bigger power factor, leading to smaller current ratings on the controller, and increasing the overall drive system efficiency.

Driving lower speeds at higher efficiency than an induction motor might delete the requirement of a speed-reduction transmission, taking the complexity out of the mechanical arrangement.

Constant torque

This type of motor can generate constant torque and maintain full torque at low speeds.

Size

The smaller size, lighter weight, and less coil provide a higher power density.

Cost-effective

With the absence of brushes, there are reduced maintenance costs.

Minimal heat

In PMSM the heat is generated on the stator coils and there are no brushes and only minimal heat generated on the rotor, facilitating the cooling of the motor. As they run cooler than induction motors, the motor's reliability and lifespan are increased.

Speed range

This type of motor can have a wide speed range with the use of Field Weakening and can adopt the maximum torque/current (MTPA) control strategy during constant torque operation.

Product tags

direct drive torque motor

,

high torque low speed electric motor

,

low speed high torque electric motor
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High Torque Direct Drive Permanent Magnet Motor Low Speed

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Product Detail
Brand Name :
ENNENG
Model Number :
PMM
Certification :
CE,UL
Place of Origin :
China
MOQ :
1 set
Price :
USD 500-5000/set
Contact Supplier
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High Torque Direct Drive Permanent Magnet Motor Low Speed

QINGDAO ENNENG MOTOR CO.,LTD.

Site Member
3 Years
shandong, qingdao
Since 2014
Business Type :
Manufacturer
Main Products :
PMAC Motor, Permanent Magnet Synchronous Motor, PMSM Electric Motor
Total Annual :
2,000,000.00-4,000,000.00
Employee Number :
100~200
Certification Level :
Site Member
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