The efficiency that everyone often says refers to the proportion of output power and input power of small DC motor of large gear reducer manufacturer, such as the loss of 3W power of small DC motor, and its actual power is only 2.55w, then the efficiency is only 85%, and where is the remaining 15% of the power?

The power lost by small DC motor is mostly released by power energy. The key reason is that the mechanical energy is not used in the original work, which makes it harmful to some mechanical energy. That is to say, to improve the efficiency of small DC motor, the gear repair of reducer must reduce the ineffective perm. What part of the small DC motor is hot?

The small DC motor is a part of the initial thought that when the total electric flow is over the magnet coil, the group call this situation copper loss, in addition to this is also iron loss, eddy current damage, etc. The iron loss is caused by the structure of the core, magnetic field and yoke of small DC motor. There are two kinds of iron consumption: hysteresis loss and eddy current loss. Hysteresis loss is the mechanical energy consumed by the rotation of the magnetic field in the permanent magnet material in small DC motor. In the permanent magnet, the direction of the magnetic field is the same, and the mechanical energy is necessary for the external magnetic field to change the direction of the magnetic field. Eddy current loss refers to the loss of eddy current in closed circuit, which can be prevented by changing the high or low flux or direction. The change of flux will lead to eddy current, and eddy current will lead to permeating. In order to reduce iron loss, the permanent magnet materials must be improved. The cost of non-consumption raw materials will be higher. The transformer core rotor can improve the resistance of raw materials to reduce eddy current. If iron loss is to be removed, the iron core and permanent magnet materials of transformer shall be cancelled, which will lead to the iron loss pre-made components. The iron loss can be reduced by the transformer free core motor, and the efficiency of small DC motor shall be more than 90%.