Magnetic bearing control device and control method are disclosed. A magnetic bearing control device according to an embodiment of the present invention comprises: a bearing control unit for outputting a plurality of switch control signals on the basis of gap information of a bearing coil and a rotor and current information applied to the bearing coil; and a coil driving unit for turning a plurality of self-formed switching elements on/off in accordance with the plurality of switch control signals and controlling the amount of current applied to the bearing coil and thus adjusting the magnetic field strength between the bearing coil and the rotor. The bearing control unit generates and outputs the plurality of switch control signals such that bootstrap capacitor charging time of the coil driving unit may be secured. Therefore, a magnetic bearing control circuit structure may be simplified by means of an additional bootstrap capacitor structure.

A system for compensating for the stresses applied to a bearing that rotatably supports a rotor shaft of a rotating machine relative to a stator of the machine. The system provides at least one sensor for measuring an input signal positioned on an element of the bearing, a module for acquiring the input signal configured to convert the input signal into a value of the deformation applied to the rolling bearing, a module for determining a compensation signal as a function of the deformation value, and an amplifier module configured to control a magnetic actuator rotatably supporting the shaft of the rotor and including at least one electromagnet, the amplifier module being configured to convert the compensation signal into a voltage signal transmitted to the electromagnet of the magnetic actuator, the magnetic actuator being configured to exert a force on the rotor shaft as a function of the voltage signal.

An electrical drive includes an electrical machine, a first converter stage connected to terminals of stator phase-windings of the electrical machine, and a second converter stage connected to intermediate points of the stator phase-windings. A control device determines first component currents and second component currents so that torque is generated in accordance with electrical machine control and magnetic levitation force is directed to a rotor of the electrical machine in accordance with levitation control when portions of the phase-windings between the terminals and the intermediate points carry both the first and second component currents and the other portions of the phase-windings carry the first component currents. The reference currents for the first converter stage are determined based on the first and second component currents, and the reference currents for the second converter stage are determined based on the second component currents.

The present disclosure relates to a stiffness enhancing mechanism for a magnetic suspension bearing, a magnetic suspension bearing including the stiffness enhancing mechanism, and a blood pump. The magnetic suspension bearing comprises a stator with stator teeth and a rotor disposed within the stator. The stiffness enhancing mechanism comprises: a rotor permanent magnet, a stator permanent magnet, and an axial driving body. The rotor permanent magnet and the rotor of the magnetic suspension bearing form a rotor assembly, which has an asymmetric structure with respect to the main plane (P) of the rotor. The stiffness enhancing mechanism is configured such that the stator permanent magnet generates a radial attractive force to the rotor permanent magnet, and the axial driving body generates an axial repulsive force to the rotor permanent magnet, wherein the magnitude of the axial repulsive force is variable with a change of an axial distance between the axial driving body and the rotor permanent magnet). The stiffness enhancing mechanism can increase the torsional stiffness of the rotor of the magnetic suspension bearing and facilitate the miniaturization of the magnetic suspension bearing.

A method for constructing an active magnetic bearing controller based on a look-up table method includes: building finite element models of an active magnetic bearing to obtain two universal Kriging prediction models in X-axis and Y-axis directions about actual suspension forces being in association with actual displacement eccentricities and actual control currents in the X-axis and Y-axis directions of the active magnetic bearing based on a universal Kriging model; creating two model state tables in the X-axis and Y-axis directions about the actual suspension forces being in association with the actual displacement eccentricities and the actual control currents to construct two look-up table modules with the two built-in model state tables, respectively; and constructing an active magnetic bearing controller by using two fuzzy adaptive PID controllers, two amplifier modules in the X-axis and Y-axis directions, the two look-up table modules, and two measurement modules in the X-axis and Y-axis directions.

There is provided a controller for magnetic levitation equipment comprising a plurality of current source modules for connecting to at least one power supply for direct current, DC, and said current source modules comprising current channels for actuating coils of the magnetic levitation equipment, and a controller device connected to the current source modules by a control connection for controlling switching of electric current by the current source modules to the current channels. The current source modules combine discrete components for amplifying and switching electric current to the current channels into a single package. In this way, manufacturing and maintenance of the controller is facilitated, since manufacturing and maintenance may be based on the current source modules instead of discrete components, e.g. gate drivers, IGBTs, power mosfets and diodes.

The present invention is to reduce the load on a control device by reliably classifying vibration modes of a rotor, thereby facilitating stabilization design of a magnetic bearing. The present invention includes: magnetic bearings including electromagnets provided at one end and the other end of a rotor to contactlessly support the one end and the other end of the rotor by the magnetic attraction forces of the electromagnets; and displacement sensors that measure an inclination at the one end of the rotor and an inclination at the other end of the rotor, in which the magnetic attraction forces of the electromagnets are controlled based on the inclinations measured by the displacement sensors.

A magnetic bearing device includes a magnetic bearing including a plurality of electromagnets, a displacement sensor configured to output an output signal in accordance with a displacement of a shaft, and a controller configured to control the electromagnets. The controller compensates for a change in levels of the output signal, the change occurring in accordance with a change in ambient temperature around the displacement sensor, based on one or more reference values correlating with the change in levels of the output signal. The one or more reference values are detected for use in controlling the rotary electric machine, a fluid machine system including the rotary electric machine, or an apparatus including the fluid machine system.

A system for compensating for the stresses applied to a bearing that rotatably supports a rotor shaft of a rotating machine relative to a stator of the machine. The system provides at least one sensor for measuring an input signal positioned on an element of the bearing, a module for acquiring the input signal configured to convert the input signal into a value of the deformation applied to the rolling bearing, a module for determining a compensation signal as a function of the deformation value, and an amplifier module configured to control a magnetic actuator rotatably supporting the shaft of the rotor and including at least one electromagnet, the amplifier module being configured to convert the compensation signal into a voltage signal transmitted to the electromagnet of the magnetic actuator, the magnetic actuator being configured to exert a force on the rotor shaft as a function of the voltage signal.

A bearingless hub assembly comprising a rim hollowed to receive a tube magnet, and magnets embedded around the circumference of the rim on both ends. The rim is capped by front and rear rim plates configured to hold the embedded magnets in place and fitted to receive respective circular magnets. Similar magnets in corresponding front or rear drive plate maintain space (i.e., levitation) vis-à-vis the front and rear rim caps by repelling each other, thus allowing the rim (and, as applied, a mechanically-attached tire assembly) to move freely with no friction. The front and rear drive plate carry forward and reverse electromagnetic actuators as well as forward and reverse levitation control units, power generators and speed sensors. These components mount 360 degrees around the circumference of the drive plates while the embedded magnets of the rim spin through when in motion.