It can be analyzed from the figure that two generator coils, two excitation coils, the excitation coil provides a horizontal magnetic field, and the structure of the generator coil must be the key to the equipment, why are there two coils instead of one generator coil, the generator coil The appearance structure is a square, the height and width are basically the same. Explain that the coil length in the horizontal direction affects the structure of the generator coil, and the length should not be too long, indicating that the width should be less than or equal to the height. On the other hand, the winding method of the coil is not the winding method of an ordinary coil, nor is it an ordinary double-wire parallel winding.