Temperature Rise Control of EC Motors
Fan EC Motor Permanent Magnet Synchronous Motor Selection Part 8 - Temperature Rise Control of EC Motors
As mentioned in the previous article, "fan EC motor is a high-performance fan power system with permanent magnet synchronous motor +FOC vector control controller, which designs and optimizes the performance, structure and power of the motor system according to the application characteristics of the fan." It is an application extension of permanent magnet synchronous motor +FOC vector control controller. Temperature rise control of fan EC motor is very important in the process of motor selection, which is mainly related to the following aspects.
Introduction of Temperature Rise Control of Fan EC Motor First, the provisions of IEC Motor Insulation Grade and National Standard for Sintered NdFeB on the maximum working temperature of the main raw materials of the motor are introduced.
Insulation temperature class A, E, B, F, H.
Maximum allowable temperature (℃)105 120 130 155 180
Rare earth NdFeB:
Sintered NdFeB, N, M, H, SH, UH, EH.
The highest working temperature (℃) is 80 100 120 150 180 200.
Rare earth NdFeB and enameled wire do not generate heat themselves. When the electric energy driving the motor to rotate passes through the copper wire, heat is generated. Exceeding the maximum working temperature specified by different grades and grades of rare earth NdFeB and enameled wire will cause demagnetization of rare earth NdFeB and breakdown of insulation layer. This will reduce the efficiency of the motor and eventually damage the motor.
The material selection of fan EC motor is not the higher, the better. According to the equipment site conditions, the enterprise's own motor design optimization capability and specific selection of production process are required. Design and selection of air gap for permanent magnet synchronous motor: Winding wire diameter conforming to actual working conditions and load characteristics; A manufacturing proces with higher tank full rate; Measures such as lower grade and thinner silicon steel sheets can effectively control the temperature rise of the permanent magnet synchronous motor of the fan.
General fan permanent magnet synchronous motors will choose F-grade insulated enameled wire and SH-grade rare earth NdFeB. Permanent magnet synchronous motors comply with Class I and IE4 energy efficiency of the National Standard for Energy Efficiency of Permanent Magnet Synchronous Motors. The coil temperature is between 20℃ and 50℃, leaving a certain margin for fan EC motors to prevent motor damage caused by possible overload or regional temperature fluctuation.