Reliability has always been an important consideration for the user to choose the motor. The longer life of the motor, the more compact structure is the embodiment of high reliability. Motor life and long temperature and temperature has a very large relationship, improve motor efficiency, reduce the temperature rise, can effectively extend the life of the motor.
Direct drive system motor structure is more compact, can achieve the highest dynamic performance, accuracy and cost-effectiveness. Due to the abandonment of mechanical transmission components, such as reducer and belt, thus simplifying the mechanical design, significantly improve the availability and reduce operating costs.
But we also see that the permanent magnet direct drive motor also has its own problems, first of all rare earth permanent magnet material costs are high, resulting in a relatively high cost of the whole machine, and secondly, is also the most important problem, permanent magnet materials in high temperature, vibration and Over-current conditions, there may be a permanent demagnetization, resulting in the overall retirement of the generator, which is a direct drive permanent magnet generator major defects. So in some of the special requirements of high reliability, direct drive motor is difficult to be preferred, asynchronous motor now has an irreplaceable advantage.