What is the role of magnetically conductive blocks in electric motors or linear motors?

1. Reduce magnetic circuit impedance:

Adding magnetically conductive blocks to the main magnetic circuit of an electric motor/linear motor can significantly reduce the relative magnetic reluctance of the circuit, making it easier for magnetic flux to pass through the main magnetic circuit.

2. Increase air gap flux density:

Magnetically conductive blocks "guide" the magnetic flux to the air gap, enhancing the fundamental component of the air gap flux, thereby increasing electromagnetic thrust or torque. Experimental data shows that after adding magnetically conductive blocks, the thrust increased from 48.32N to 84.25N, an increase of 74%.

3. Affect harmonics and ripple:

Although the fundamental frequency is significantly improved, magnetically conductive blocks also amplify higher harmonics (such as the 4th and 12th harmonics), causing the thrust ripple to increase from 0.16% to approximately 7%. By optimizing the block height, chamfer radius, and coil width, the ripple can be controlled to around 3–4% while maintaining high thrust. 4. Increased core losses: The magnetic flux is concentrated in the core area, which significantly increases hysteresis loss and eddy current loss, requiring corresponding compensation in the heat dissipation design.