Abstract:
A digital nonlinear corrector of an active magnetic bearing receiving an input signal x(t) and outputting an output control signal u(t) for controlling the position of said active magnetic bearing, the input signal being digitalized by a ADC circuit and provided to an adder, the digital nonlinear corrector comprising a closed control loop delivering an intermediary sequence of numbers y[kT] and having a direct branch comprising a first proportional gain circuit and a feedback branch comprising a series connection of a low-pass filter and a dead zone circuit, such that said low-pass filter is activated when determined upper and lower values of said output control signal are reached, the output control signal reproducing the input signal when these determined upper and lower values are not reached.
Abstract:
A magnetic bearing, comprising: a magnetic base; at least three actuator bobbins mounted on the magnetic base; and magnetic sensors associated with the actuator bobbins. At least one magnetic system amidst the magnetic actuators and the magnetic sensors comprises together: a coil holder; a coil wound up around the coil holder; and a connector device integrated to the coil holder and designed for plugging at least one wire. Additionally disclosed is an apparatus comprising such a magnetic bearing and a method for manufacturing such a magnetic bearing.
Abstract:
A position detection device of active magnetic bearings (AMB's) maintaining the position of a rotating shaft and comprising two sensing inductance coils, the position detection device comprising a programmable digital component for generating a 25 KHz square waveform signal, a current amplifier receiving the 25 KHz square waveform signal and injecting two identical control currents in the two sensing inductance coils, a differential amplifier for amplifying a voltage difference between the resulting voltages in the two sensing inductance coils and, depending on the displacement of the rotating shaft, an analog to digital (A/D) converter for delivering a position value from the voltage difference.
Abstract translation:一种主动磁轴承(AMB)的位置检测装置,其保持旋转轴的位置并且包括两个感测电感线圈,该位置检测装置包括用于产生25KHz方波信号的可编程数字分量,接收25KHz的电流放大器 在两个感测电感线圈中注入两个相同的控制电流的差分放大器,用于放大两个感测电感线圈中产生的电压之间的电压差的差分放大器,并且根据旋转轴的位移,模拟数字( A / D)转换器,用于从电压差传递位置值。
Abstract:
An electronic magnetic bearing controller for controlling the position of a rotor of an electrical machine supported by an active magnetic bearing the position of which being measured by at least one inductive position sensor having an inductive coil, comprising an automatic reactive power compensation device for automatically compensating the reactive power consumed by the inductive position sensor.
Abstract:
A rotor sensor target for magnetic bearings, the rotor sensor target comprising a ring-shaped assembly of magnetic material mounted on a generally ring-shaped assembly of non-magnetic material. The magnetic and non-magnetic ring shaped assemblies are coaxially arranged and mounted on a shaft having a longitudinal axis of rotation X′-X. The generally ring-shaped assembly of non-magnetic material comprises at least one ring-shaped slit having the longitudinal axis X′-X and may be made of a cheaper material, such as aluminum. The ring-shaped slit provides flexibility which permits operation over a wide range of temperatures without risking of damaging the ring-shaped assembly of magnetic material.
Abstract:
A thrust disc for a magnetic bearing, wherein the thrust disc comprises: a body, which is adapted to be mounted on a shaft and which has a first offset yield strength and a first magnetic permeability, and at least one flange which is fixed to the body in a position where it can interact with a thrust stator in order to form a magnetic bearing and which has a second offset yield strength and a second magnetic permeability; wherein the first offset yield strength is higher than the second offset yield strength; and wherein the first magnetic permeability is smaller than the second magnetic permeability. Additionally, the magnetic bearing can be equipped with such a thrust disc. An apparatus can be equipped with such a magnetic bearing.
Abstract:
A jacketed electromagnetic machine stator for a pressurized rotary machine operating in a corrosive atmosphere containing H2S or wet CO2 and including a plurality of pole pieces separated from a rotor by an airgap, wherein the hermetically sealed enclosure protecting said stator from said corrosive atmosphere includes a jacket constituted by a non-magnetic cylinder having magnetic material inlays situated in register with said pole pieces and that are not in contact with said corrosive atmosphere, said hermetically sealed enclosure being constituted externally solely by parts made of non-magnetic material that are secured to one another by welds that have not been subjected to any heat treatment.
Abstract:
An assembly that includes a rotating shaft supported with respect to a stationary housing by at least one active magnetic bearing presenting a mean radial air gap and at least one auxiliary bearing having a bushing fixed to the housing and a sleeve fixed on the rotating shaft. The bushing and the sleeve have opposite surfaces that define a clearance (E2) which is less than the mean radial air gap (E1). The bushing and the sleeve each exhibit symmetry around a longitudinal axis of the shaft and have different profiles in a longitudinal cross-section including the longitudinal axis to optimize the contact pressure distribution when the rotating shaft lands on the auxiliary bearing.
Abstract:
A device for detecting the axial position of a rotary shaft of a rotary machine comprises a target of ferromagnetic material placed at the end of the rotary shaft, an induction coil associated with a stationary magnetic circuit and placed facing the target while leaving an airgap, and a power supply circuit. The power supply circuit comprises an AC voltage source connected between a first end of the induction coil and a zone situated at a reference voltage, at least one capacitor connected between the ends of the induction coil, and a detector device interposed between a second end of the induction coil and the zone situated at the reference voltage, in order to deliver on a line information about the magnitude of the current flowing between the second end and the zone situated at the reference voltage.