Excitation winding dual-mode switching system of hybrid excitation motor and current control mode

Abstract

The invention discloses an excitation winding dual-mode switching system of a hybrid excitation motor and a current control mode, the excitation winding dual-mode switching system comprises an armature winding, an excitation winding, power converters and a relay switch, and the armature winding and the excitation winding are respectively connected with different power converters for power supply; the armature winding and the excitation winding are connected or separated by controlling the relay switch, when the hybrid excitation motor does not need the excitation winding to adjust magnetism, the excitation winding and the armature winding are connected in series by controlling the relay switch, and at the moment, the excitation winding serves as a part of the armature winding, so that the output torque of the motor can be increased; when the hybrid excitation motor needs magnetic increasing or magnetic weakening of the excitation winding, the excitation winding and the armature winding are separated by controlling a relay switch, and the excitation winding and the armature winding work independently and parallelly, so that the output torque of the motor is improved; and each phase of excitation winding in the hybrid excitation motor adopts a current intermittent working mode, so that the loss of the excitation winding is reduced, and the working efficiency of the motor is improved.

Description

Technical field [0001] The present invention relates to the field of motor control, in particular to an excitation winding dual-mode switching system and current control mode of a hybrid excitation motor. Background [0002] Hybrid excitation motors have the advantages of small excitation loss and high efficiency, and have gained wider attention and application; In order to improve the efficiency of the motor, the excitation potential of the hybrid excitation motor is usually dominated by the permanent magnet potential, supplemented by the electric excitation potential, and the permanent magnet potential is significantly greater than the electroexcitation potential. Therefore, in the normal operating state, the motor is usually excited by the permanent magnet, and the electric excitation winding has no current flowing; When the motor needs to run in a low-speed overload state, the electric excitation winding passes through the forward DC current, so that the electrical excitation...

AI Technical Summary

Problems solved by technology

Due to the low utilization rate of the excitation winding, the hybrid excitation motor usually sacrifices a small part of the armature winding space in exchange for the magnetic field adjustment capability, so its torque density is slightly lower than that of the permanent magnet motor

[0003] And the winding method of the armature windings A, B, C and the field windings FA, FB, FC in the hybrid excitation motor is as follows: the field coil is wound on the middle stator pole of a stator pole group composed of three consecutive stator poles , the armature coil is wound across the three stator poles corresponding to the stator pole group, and multiple armature coils of the same phase are connected in series or in parallel or mixed to form the armature winding of the phase; the excitation coil surrounded by the armature coil of the same phase is phase The corresponding field windings are formed in series or in parallel; the armature winding is used for the output of the motor, and the field winding is used for the adjustment of the motor magnetic field. Taking the new flux reversal three-phase double salient pole motor with 18 / 10 structure as an example, its motor structure as attached Image 6 As shown; according to the structure and working principle of the motor, the alignment position of the stator pole in the middle of the A-phase winding is set to be the electrical angle position of 0 degrees; when the angle is in the interval [-90°, 90°], the exciting current of the A-phase is A, B, C The three phases provide excitation flux, and the three phases output force simultaneously; when the electrical angle is in a range around 180°, the armature current of phase A mainly interacts with the magnetic field established by the excitation currents of phases B and C to generate output torque, and the phase A The excitation current contributes little to the output of the motor, and will generate a large leakage flux, thereby increasing the core loss of the motor

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