Benefits of PMSM motors:
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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.

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.

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.

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.

A few small problems that are easily overlooked about the motor:

1. Why can't general motors be used in plateau areas?

Altitude has adverse effects on motor temperature rise, motor corona (high voltage motor) and commutation of DC motor. The following three aspects should be noted:

(1) The higher the altitude, the higher the temperature rise of the motor, the lower the output power. However, when the temperature decreases with the increase of altitude enough to compensate for the influence of altitude on the temperature rise, the rated output power of the motor can remain unchanged;

(2) Anti-corona measures should be taken when the high-voltage motor is used in the plateau;

(3) The altitude is not good for the commutation of the DC motor, so pay attention to the selection of carbon brush materials.

2. Why is the motor not suitable for light load operation?

When the motor runs at light load, it will cause:

(1) The power factor of the motor is low;

(2) The motor efficiency is low.

(3) It will cause equipment waste and uneconomical operation.

3. Why can't the motor start in cold environment?

Excessive use of the motor in a low temperature environment will cause:

(1) Motor insulation cracks;

(2) Bearing grease freezes;

(3) The solder powder of the wire joint is powdered.

Therefore, the motor should be heated and stored in a cold environment, and the windings and bearings should be checked before running.

4. Why can't a 60Hz motor use a 50Hz power supply?

When the motor is designed, the silicon steel sheet generally works in the saturation region of the magnetization curve. When the power supply voltage is constant, reducing the frequency will increase the magnetic flux and the excitation current, resulting in an increase in the motor current and copper consumption, which will eventually lead to an increase in the temperature rise of the motor. In severe cases, the motor may be burned due to overheating of the coil.

5.Motor soft start

Soft start has limited energy-saving effect, but it can reduce the impact of start-up on the power grid, and can also achieve smooth start to protect the motor unit. According to the theory of energy conservation, due to the addition of a relatively complex control circuit, soft start not only does not save energy, and also increases energy consumption. But it can reduce the starting current of the circuit and play a protective role.