SUNGLASSES DRESIGN

These six phase motors are designed based on permanent magnet synchronous brushless servo motors, using a dual three phase winding asymmetric phase shift design of 30 ° (with a 30 degree interval between the two sets of windings). All intermediate nodes of the six phase motors (dual three-phase windings) are led out, with a total of 12 motor leads and a built-in 2500 wire photoelectric encoder or rotary converter. It can be widely used in ship propulsion systems, automotive power systems, power control systems, and other high-end power systems.

The phase band angle of the asymmetric six phase motor is consistent with that of the symmetric twelve phase motor, which is 30 °. Therefore, its magnetic potential spatial distribution is consistent with that of the symmetric twelve phase motor, that is, the asymmetric six phase motor eliminates the 5th and 7th harmonic magnetic potentials internally, thereby eliminating the 6th torque ripple. The minimum number of torque pulsations has been increased to 12, thus it has a greater advantage in suppressing torque pulsations.

A six phase motor can achieve high power output at low voltage. As the number of phases in the motor increases, the permanent magnet flux or back electromotive force of each phase winding will decrease proportionally, resulting in a decrease in the supply voltage, which can achieve high power output at low voltage.

When one or more phase faults occur in the stator winding of a six phase motor, it can be operated at reduced capacity without the need for a neutral line, and there is no need to stop and reassemble. In this case, by adopting an appropriate fault-tolerant control strategy, the remaining motor windings can be recombined into a circular rotating magnetic potential trajectory, allowing the motor to continue stable operation. Therefore, multiphase motors are very suitable for high reliability requirements where mid stop is strictly prohibited.

As the number of motor phases increases, the number of spatial harmonics increases, and the frequency of torque ripple increases

High amplitude reduces the noise and vibration during motor operation. The more phases a motor has, the higher the frequency of torque ripple generated by the fundamental current.

For a six phase motor, constant torque can be generated by injecting a suitable ratio of low order harmonic current and corresponding harmonic magnetic field, thereby increasing the power density of the motor. The spatial voltage vector of multiphase inverters increases exponentially, providing abundant control resources for the control of multiphase motors, such as PWM modulation, direct torque control, and predictive current control. Multiphase motors can achieve decoupling of fundamental torque components and harmonic components through vector space decoupling; By controlling the harmonic sub plane components, dead zone compensation and asymmetric compensation can be achieved; Overmodulation and parameter identification can also be achieved by injecting harmonic components.