Special permanent magnet direct drive motor for belt conveyor:

The special low-speed high-power permanent magnet drive system for belt conveyors is a high-efficiency and energy-saving direct-drive electric drive system, which directly drives the load equipment. Different from the traditional asynchronous motor, the selection of the system depends on the actual equipment speed range and the equipment load torque. The specific selection rules are as follows:

Determine the motor speed range according to the belt speed and roller outer diameter of the belt conveyor, to select the motor drive system whose speed range is not less than and closest to the actual demand. The standard rated speed is 0~60r/min, 0~75r/min, 0~90r/min, and other speed ranges can be adjusted and customized according to the actual requirements of customers.

Confirm the torque required by the belt conveyor first to select the appropriate permanent magnet drive system. The actual torque of the equipment can also be calculated according to the parameters of a traditional asynchronous motor and the speed ratio of the reducer.

Determine the rated voltage of the motor. The common voltage of the motor under the torque of 30000N.m is 380V, 660V, 1140V. The motor voltage above the torque of 30000N.m is 1140V, 3300V, 6kV, 10kV. Other voltage levels can be customized according to customer needs.

The motor cooling mode includes natural cooling, forced air cooling, and water cooling, which can be selected according to customer's actual needs.

The motors can be designed and manufactured according to the technical parameters provided by users.

Why choose permanent magnet AC motors?

Permanent magnet AC (PMAC) motors offer several advantages over other types of motors, including:

High Efficiency: PMAC motors are highly efficient due to the absence of rotor copper losses and reduced winding losses. They can achieve efficiencies of up to 97%, resulting in significant energy savings.

High Power Density: PMAC motors have a higher power density compared to other motor types, which means they can produce more power per unit of size and weight. This makes them ideal for applications where space is limited.

High Torque Density: PMAC motors have a high torque density, which means they can produce more torque per unit of size and weight. This makes them ideal for applications where high torque is required.

Reduced Maintenance: Since PMAC motors have no brushes, they require less maintenance and have a longer lifespan than other motor types.

Improved Control: PMAC motors have better speed and torque control compared to other motor types, making them ideal for applications where precise control is required.

Environmentally Friendly: PMAC motors are more environmentally friendly than other motor types since they use rare earth metals, which are easier to recycle and produce less waste compared to other motor types.

Overall, the advantages of PMAC motors make them an excellent choice for a wide range of applications, including electric vehicles, industrial machinery, and renewable energy systems.

How to prevent the demagnetization of permanent magnet motors?

01. Correct selection of permanent magnet motor power:

Demagnetization is related to the power selection of permanent magnet motors. Correct selection of PM motor power can prevent or delay demagnetization. The main reason for the demagnetization of the permanent magnet synchronous motor is that the temperature is too high, and the overload is the main reason for the high temperature. Therefore, a certain margin should be left when selecting the power of the permanent magnet motor. According to the actual situation of the load, generally, about 20% is more appropriate.

02. Avoid heavy load starting and frequent starting:

Permanent magnet synchronous motors try to avoid direct starting or frequent starting of heavy loads. During the starting process, the starting torque oscillates, and in the valley section of the starting torque, the stator magnetic field is demagnetizing the rotor magnetic pole. Therefore, try to avoid the heavy load and frequent starting of the permanent magnet synchronous motor.

03. Improve the design:

(1) Appropriately increase the thickness of the permanent magnet:

From the perspective of permanent magnet synchronous motor design and manufacture, the relationship between armature reaction, electromagnetic torque, and permanent magnet demagnetization should be considered.

Under the combined action of the magnetic flux produced by the torque winding current and the magnetic flux produced by the radial force winding, the permanent magnets on the rotor surface easily cause demagnetization.

Under the condition that the air gap of the motor remains unchanged, to ensure that the permanent magnet does not demagnetize, the most effective method is to appropriately increase the thickness of the permanent magnet.

(2) There is a ventilation groove circuit inside the rotor to reduce the temperature rise of the rotor:

If the temperature of the rotor is too high, the permanent magnet will cause irreversible loss of magnetism. In the structural design, the internal ventilation circuit of the rotor can be designed to directly cool the magnetic steel. Not only reduces the temperature of the magnetic steel but also improves the efficiency.