Sign In | Join Free | My himfr.com |
|
Ask Lasest Price | |
Brand Name : | ENNENG |
Model Number : | PMM |
Certification : | CE,UL |
Price : | USD 500-5000/set |
Payment Terms : | L/C, T/T |
Supply Ability : | 20000 sets/year |
Delivery Time : | 15-120 days |
Energy Saving Small Size High-Efficiency Interior Permanent Magnet Motor
What Is The Permanent Magnet Synchronous Motor?
The Permanent Magnet Synchronous Motor (PMSM) is a type of electric
motor that operates using permanent magnets embedded in its rotor.
It is also sometimes referred to as a brushless AC motor or a
synchronous permanent magnet motor.
In a PMSM, the stator (the stationary part of the motor) contains a
series of coils that are energized in a sequence to create a
rotating magnetic field. The rotor (the rotating part of the motor)
contains a series of permanent magnets that are arranged to produce
a magnetic field that interacts with the magnetic field produced by
the stator.
As the two magnetic fields interact, the rotor rotates, producing
mechanical energy that can be used to power machinery or other
devices. Because the permanent magnets in the rotor provide a
strong, constant magnetic field, PMSMs are highly efficient and
require less energy to operate than other types of electric motors.
PMSMs are used in a wide variety of applications, including
electric vehicles, industrial machinery, and household appliances.
They are known for their high efficiency, low maintenance
requirements, and precise control, which makes them a popular
choice for many different types of systems.
Working of Permanent Magnet Synchronous Motor
The working of the permanent magnet synchronous motor is very simple, fast, and effective when compared to conventional motors. The working of PMSM depends on the rotating magnetic field of the stator and the constant magnetic field of the rotor. The permanent magnets are used as the rotor to create constant magnetic flux and operate and lock 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, and 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.
Analysis of the principle of the technical advantages of permanent
magnet motor
The principle of a permanent magnet synchronous motor is as
follows: In the motor's stator winding into the three-phase
current, after the pass-in current, it will form a rotating
magnetic field for the motor's stator winding. Because the rotor is
installed with the permanent magnet, the permanent magnet's
magnetic pole is fixed, according to the principle of magnetic
poles of the same phase attracting different repulsion, the
rotating magnetic field generated in the stator will drive the
rotor to rotate, The rotation speed of the rotor is equal to the
speed of the rotating pole produced in the stator.
Back-emf waveform:
>
>
>
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.
Permanent magnet AC (PMAC) motors have a wide range of applications
including:
Industrial Machinery: PMAC motors are used in a variety of
industrial machinery applications, such as pumps, compressors,
fans, and machine tools. They offer high efficiency, high power
density, and precise control, making them ideal for these
applications.
Robotics: PMAC motors are used in robotics and automation
applications, where they offer high torque density, precise
control, and high efficiency. They are often used in robotic arms,
grippers, and other motion control systems.
HVAC Systems: PMAC motors are used in heating, ventilation, and air
conditioning (HVAC) systems, where they offer high efficiency,
precise control, and low noise levels. They are often used in fans
and pumps in these systems.
Renewable Energy Systems: PMAC motors are used in renewable energy
systems, such as wind turbines and solar trackers, where they offer
high efficiency, high power density, and precise control. They are
often used in the generators and tracking systems in these systems.
Medical Equipment: PMAC motors are used in medical equipment, such
as MRI machines, where they offer high torque density, precise
control, and low noise levels. They are often used in the motors
that drive the moving parts in these machines.
Depending on how magnets are attached to the rotor and the design
of the rotor, permanent magnet synchronous motors can be classified
into two types:
Surface permanent magnet synchronous motor (SPMSM)
Interior permanent magnet synchronous motor (IPMSM).
SPMSM mounts all magnet pieces on the surface, and IPMSM places
magnets inside the rotor.
Advantages
Small And Lightweight
In special electromagnetic and structural design, the
volume-to-weight ratio is reduced by 20%, the length of the whole
machine is reduced by 10%, and the full rate of stator slots is
increased to 90%.
Highly Integrated
The motor and the inverter are highly integrated, avoiding the
external circuit connection between the motor and the inverter, and
improving the reliability of the system products.
Energy Efficient
High-performance rare-earth permanent magnet material, special
stator slot, and rotor structure make this motor efficient up to
IE4 standard.
Custom Design
Customized design and manufacture, dedicated to special machines,
reduce redundant functions and design margins and minimize costs.
Low Vibration And Noise
The motor is directly driven, the equipment noise and vibration are
small, and the impact on the construction work environment is
reduced.
Maintenance Free
No high-speed gear parts, no need to change gear lubricant
regularly, and truly maintenance-free equipment.
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.
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.
Why you should choose an IPM motor instead of an SPM?
1. High torque is achieved by using reluctance torque in addition to magnetic torque.
2. IPM motors consume up to 30% less power compared to conventional electric motors.
3. Mechanical safety is improved as, unlike in an SPM, the magnet will not detach due to centrifugal force.
4. It can respond to high-speed motor rotation by controlling the two types of torque using vector control.
![]() |