How to improve motor efficiency?

Studying motor efficiency is essentially analyzing the process of various losses and identifying the key factors that affect them.

Reduce losses when current flows through the winding. The most direct way to improve motor efficiency is to reduce armature winding losses. For example, by increasing the slot area to use more copper to increase the cross-sectional area of the winding and reduce its resistance, the losses caused by current flowing through the winding can be reduced.

Control of iron core loss. The iron core loss is related to two major factors: magnetic flux density and frequency in the iron core. Usually, the power frequency is fixed, so in order to reduce iron core losses, the method of lengthening the iron core is generally adopted.

The improvement of efficiency is closely related to material consumption. In order to achieve the required energy consumption level, an increase in copper usage and iron core volume is inevitable. However, the decrease in losses is not always positively correlated with the increase in copper and iron consumption. When the cross-section of the iron core and coil increases to a certain extent, the loss will actually increase, because the increase in the volume of the iron core will also increase the loss of the iron core and coil. If it exceeds the reduction caused by the decrease in resistance and iron core unsaturation, the efficiency will actually decrease. There may be a point beyond which the loss actually increases when increasing the volume of the iron core. Similarly, for a certain magnetic flux density, eddy current losses can be reduced by using thinner laminations.

Technological innovation enhances efficiency. Breaking through the technical barriers of closed slot rotors and cast copper rotors, the efficiency level of the motor will achieve a qualitative leap.