Abstract: The present disclosure provides a stator core, a magnetic levitation bearing, and a motor. The stator core is used in the magnetic levitation bearing and includes an annual yoke. The annular yoke has an inner circumferential wall and an outer circumferential wall, a plurality of pole pillars are disposed on the inner circumferential wall, and each of the plurality of pole pillars extends towards an axis of the inner circumferential wall, there is a distance D between an axis of the outer circumferential wall and the axis of the inner circumferential wall, and D?0 is satisfied. According to the stator core, the magnetic levitation bearing, and the motor of the present disclosure, the stator core has a non-centrosymmetric structure, so that a cross-sectional area of a magnetic path in some region of the stator core is increased, which is beneficial to an improvement of an output force of the magnetic levitation bearing.

Abstract: The present disclosure relates to a stator of a magnetic levitation bearing, a magnetic levitation bearing, and a compressor. The stator of the magnetic levitation bearing includes a stator core (4), a stator coil (5) wound around the stator core (4), a housing (2) sleeved outside the stator core (4) and having a clearance fit or a transition fit with the stator core (4), and a potting component (3) filled between the housing (2) and the stator core (4).

Abstract: A fault processing method for a displacement sensor includes: receiving a plurality of detected signals from a plurality of detecting probes and a given signal of a spare probe, wherein the detecting probes are configured to detect a displacement value of a rotation shaft of a magnetic levitation motor to obtain the detected signals, and the spare probe is configured to replace a faulty probe among the plurality of detecting probes; determining whether there is a faulty probe among the plurality of detecting probes based on the plurality of detected signals and the given signal; and connecting the given signal of the spare probe to the faulty probe corresponding to a case that a determination result is yes.

Abstract: The present disclosure provides a stator core, a magnetic levitation bearing, and a motor. The stator core is used in the magnetic levitation bearing and includes an annual yoke. The annular yoke has an inner circumferential wall and an outer circumferential wall, a plurality of pole pillars are disposed on the inner circumferential wall, and each of the plurality of pole pillars extends towards an axis of the inner circumferential wall, there is a distance D between an axis of the outer circumferential wall and the axis of the inner circumferential wall, and D?0 is satisfied. According to the stator core, the magnetic levitation bearing, and the motor of the present disclosure, the stator core has a non-centrosymmetric structure, so that a cross-sectional area of a magnetic path in some region of the stator core is increased, which is beneficial to an improvement of an output force of the magnetic levitation bearing.

Abstract: The present disclosure provides a power supply system for a magnetic bearing and a control method therefor. The system includes a rectifying and filtering circuit configured to rectify and filter an alternating current to obtain a first direct current with a first DC bus voltage, the first direct current being configured to supply power to an electric motor controller of an electric motor to which the magnetic bearing belongs; a power obtaining circuit configured to obtain a second direct current with a second DC bus voltage from the first direct current, the second DC bus voltage being within an input voltage range allowed by the DC-DC power supply; a DC-DC power supply configured to convert the second direct current to a third direct current with a third DC bus voltage, the third direct current being configured to supply power to a bearing controller of the magnetic bearing.

Abstract: A power consumption control device includes: a voltage detection circuit configured to detect whether an input power supply of a magnetic levitation system to be controlled is turned off; and a comparison unit configured to detect an operating parameter of a motor of the magnetic levitation system during an operation of the motor as a generator, and compare the operating parameter with a set parameter to obtain a comparison result; a motor controller of the magnetic levitation system controls the motor of the magnetic levitation system to operate as the generator in a case that the input power supply is turned off, a bearing controller of the magnetic levitation system adjusts a magnitude of a bearing bias current of the magnetic levitation system according to the comparison result, to control a power consumption of a magnetic levitation bearing of the magnetic levitation system within a set range.

Abstract: Disclosed is a displacement correction apparatus. The apparatus comprises: a reference circuit and a correction circuit; the reference circuit is configured to provide a reference signal; the correction circuit is configured to perform a logarithm operation on a nonlinear displacement signal to be corrected based on the reference signal, to obtain a corrected linear displacement signal. The displacement correction apparatus can solve the problem of poor detection accuracy resulting from a position signal output by an eddy current sensor being not in a linear relationship with a displacement signal of a shaft, thereby achieving the effect of improving detection accuracy. A magnetic levitation bearing system and a displacement correction method therefor which use the above displacement correction apparatus are also disclosed.

Abstract: A control method for a magnetic bearing includes following steps: acquiring a suspension stopping instruction for the magnetic bearing, and respectively applying a control current to one or more control coils of the magnetic bearing to subject a rotor to a vertically or obliquely upwards electromagnetic force, a vertical component of the electromagnetic force is less than the gravity of the rotor. A control device for a magnetic bearing is also disclosed, including a suspension stopping instruction acquiring unit and a control current applying unit. The control method and control device for a magnetic bearing can control a falling velocity of the rotor to be lower than that of the rotor being subjected only to the gravity, and have higher control efficiency.

Abstract: Provided are a method and a system for detecting bend in the rotating shaft of magnetic bearing. The system comprises a first displacement sensor, a second displacement sensor, and a processor electrically connected with the first displacement sensor and the second displacement sensor; the processor comprises a calculating unit, a first judging unit and a second judging unit; the calculating unit is configured to calculate center positions of the rotating shaft stopping at different positions during rotating a circle; the first judging unit judges whether the rotating shaft is bent or not according to a curve of the changed center positions, and outputs a test result of qualification if the rotating shaft is not bent. Users are able to determine whether the rotating shaft needs to be processed or not, to avoid causing destructive effects on the magnetic bearing system due to excessive bend degree of the rotating shaft.

Abstract: The present disclosure provides a power supply system for a magnetic bearing and a control method therefor. The system includes a rectifying and filtering circuit configured to rectify and filter an alternating current to obtain a first direct current with a first DC bus voltage, the first direct current being configured to supply power to an electric motor controller of an electric motor to which the magnetic bearing belongs; a power obtaining circuit configured to obtain a second direct current with a second DC bus voltage from the first direct current, the second DC bus voltage being within an input voltage range allowed by the DC-DC power supply; a DC-DC power supply configured to convert the second direct current to a third direct current with a third DC bus voltage, the third direct current being configured to supply power to a bearing controller of the magnetic bearing.

Abstract: Provided are a protection circuit for a brushless DC motor, and a control device. The protection circuit is applied to a control device for a brushless DC motor, the control device including a main control chip and a protection circuit for driving a brushless DC motor. The protection circuit includes a sampling signal input end (RNF), a first resistor (R1), a first capacitor (C1), a second capacitor (C2), a comparator (IC2) and a switching element (IC1), connected together in a preset structure.

Abstract: A shaft control method and device for a magnetic suspension system. The shaft control method for the magnetic suspension system includes: acquiring a displacement signal obtained by detecting displacement of a shaft in the magnetic suspension system (Step 101); separating whirling displacement from the displacement signal (Step 102); and controlling whirling of the shaft according to the whirling displacement (Step 103). By the disclosure, the effect of suppressing the whirling of the shaft during high-speed rotation of the magnetic suspension system is achieved.

Abstract: Provided are a method and a system for detecting bend in the rotating shaft of magnetic bearing. The system comprises a first displacement sensor, a second displacement sensor, and a processor electrically connected with the first displacement sensor and the second displacement sensor; the processor comprises a calculating unit, a first judging unit and a second judging unit; the calculating unit is configured to calculate center positions of the rotating shaft stopping at different positions during rotating a circle; the first judging unit judges whether the rotating shaft is bent or not according to a curve of the changed center positions, and outputs a test result of qualification if the rotating shaft is not bent. Users are able to determine whether the rotating shaft needs to be processed or not, to avoid causing destructive effects on the magnetic bearing system due to excessive bend degree of the rotating shaft.

Abstract: Provided are a protection circuit for a brushless DC motor, and a control device. The protection circuit is applied to a control device for a brushless DC motor, the control device including a main control chip and a protection circuit for driving a brushless DC motor. The protection circuit includes a sampling signal input end (RNF), a first resistor (R1), a first capacitor (C1), a second capacitor (C2), a comparator (IC2) and a switching element (IC1), connected together in a preset structure.

Abstract: A control method for a magnetic bearing comprises following steps: acquiring a suspension stopping instruction for the magnetic bearing, and respectively applying a control current to one or more control coils of the magnetic bearing to subject a rotor to a vertically or obliquely upwards electromagnetic force, a vertical component of the electromagnetic force is less than the gravity of the rotor. A control device for a magnetic bearing is also disclosed, comprising a suspension stopping instruction acquiring unit and a control current applying unit. The control method and control device for a magnetic bearing can control a falling velocity of the rotor to be lower than that of the rotor being subjected only to the gravity, and have higher control efficiency.

Abstract: A shaft control method and device for a magnetic suspension system. The shaft control method for the magnetic suspension system includes: acquiring a displacement signal obtained by detecting displacement of a shaft in the magnetic suspension system (Step 101); separating whirling displacement from the displacement signal (Step 102); and controlling whirling of the shaft according to the whirling displacement (Step 103). By the disclosure, the effect of suppressing the whirling of the shaft during high-speed rotation of the magnetic suspension system is achieved.