The motor structure of the direct drive system is more compact, achieving the highest dynamic performance, accuracy and cost effectiveness. The elimination of mechanical transmission components, such as reducers and belts, simplifies mechanical design, significantly increases usability and reduces operating costs.

The permanent magnet direct drive motor also has its own problems. Firstly, the high cost of the rare earth permanent magnet material leads to the relatively high cost of the whole machine. Secondly, it is also the most important problem. The permanent magnet material has high temperature, vibration and over current conditions. It may be permanently demagnetized, causing the generator to be scrapped as a whole, which is a major defect of the direct drive permanent magnet generator. Therefore, in some places where reliability is required, direct drive motors are difficult to be the first choice.

At present, the technology maturity of direct drive motors is still not high, and it is developing well in the field of low power applications, but the application technology in the field of high power is not very mature. Asynchronous motors still have irreplaceable advantages for high reliability technical requirements.