Harmonic Suppression And Faulty-tolerant Control Of Dual Three-Phase PMSM

With the development of modern control theory and microelectronics technology, phase number of AC motor system is no longer restricted, which exploits sufficient advantages of multi-phase motor control system. Compared to the traditional three-phase motor control system, multi-phase motor control system has the advantages such as low power-high power, high reliability. Dual-three phase permanent magnet synchronous motor(DTP-PMSM) has the advantage of permanent magnet motor and multiphase motors.In this paper, the DTP-PMSM was decoupled from six-dimension to three two-dimensional orthogonal sub-planes by using space vector decoupling, and the mathematic model was established in rotating coordinate system. Then the DTP-PMSM’s decoupling control can be achieved by setting the reference of d-axis stator current to zero. To reduce the undesired stator harmonic current, an improved vector control method is proposed based on the proportional resonant (PR) controller. The simulation results show that the strategy can result in a decrease of power consumption and inverter capacity and improvement of its performance.This paper also analyzed the fault-tolerant of DTP-PMSM based on two different methods. The first method based on invariable stator magnetic potential by adjusting currents amplitudes and phase angles. The second adopts a second rotational transformation to achieve asymmetric motor control system decoupling control. This paper also analyzed the effects of different neutral connections for fault tolerant control methods. And presented a unified model of DTP-PMSM under phase open. This model illustrates the coupling relationships between voltage equations. Then we propose a second rotational transformation to eliminating the coupling relationship. And a vector control method based on the minimum stator current amplitude was proposed, which makes asymmetric system have the similar control performance of DC separately excited motor.Finally, the experimental platform was established. Experiments have been carried out on the new platform.