When the motor windings are distributed in the core slo […]
When the motor windings are distributed in the core slots, they must be embedded and connected according to a certain rule in order to output symmetrical sinusoidal alternating current or generate a rotating magnetic field. In addition to some other parameters, we also need to use the concept of electrical cost when reflecting the law of the relative position between the coils and windings. It is known from mechanics that a circle can be equally divided into 360 °, and this 360 ° is usually the mechanical angle. In electrical engineering, the angle unit for measuring the electromagnetic relationship is called electrical angle, which is to divide each cycle of sinusoidal alternating current on the abscissa into 360 °, that is, the conductor space changes electromagnetically by 360 when it passes through a pair of magnetic poles. ° Electrical angle.
Therefore, the relationship between the electrical angle and the mechanical angle in the motor is: electrical angle α = number of pole pairs xPx360 °. For example, for a two-pole motor, the number of pole pairs is p = 1, and the electrical angle is equal to the mechanical angle. For a four-pole motor, p = 2, when the motor has two pairs of magnetic poles on one circumference, the corresponding electrical angle is 2 × 360 °. = 720 °. And so on.