Abstract:
A permanent magnet rotor shaft assembly for a high speed electrical machine provides a permanent magnet cylindrical core having a longitudinal axis, the cylindrical core being axially compressed by first and second end shafts and being radially compressed by a sleeve made of a non-magnetic high strength metal. At least one of the first and second end shafts includes, facing the cylindrical core, a central shoulder head that cooperates with a mating central recess made in a central portion of a front face of the cylindrical core. An easy concentric alignment of the first and second end shafts with the permanent magnet cylindrical core is allowed while inserting the sleeve and the stiffness of the assembled set is enhanced.
Abstract:
An axial magnetic bearing comprising a rotor stop disc which is mounted perpendicularly and integral with a rotating shaft and a coaxially stator assembly and comprising at least one stator element of magnetic material having an inner face parallel to a side of the rotor stop disc and separated from it by an air gap, the at least one stator element comprising two annular coils and housed in two annular notches formed continuously in the magnetic material of the at least one stator element and opening to the side of the rotor stop disc, the two annular notches being separated by an annular tooth, rolled in series and are formed by a single continuous wire, a bridging recess being cut in the annular tooth for receiving a massive insert part that extends the annular tooth without locally modifying the air gap with the rotor stop disc.
Abstract:
The invention concerns an electrical installation providing an apparatus, a three-phase inverter and a control device, the inverter being adapted for generating a three-phase current presenting a first frequency for operating the apparatus and an undesired frequency component presenting a second frequency. The control device is adapted for measuring a parameter of each phase of the current, the measured parameters forming a measurement vector, and for calculating a Clarke transform, providing a first vector represented in a first basis of a two-dimensional vector space, of the measurement vector. The control device is adapted for generating a representation of the first vector in a second basis of the vector space, the second basis rotating at the second frequency with respect to the first basis.
Abstract:
A method of protecting ferromagnetic lamination stacks of a component of an electric machine, comprises the following steps: creating a component module by arranging a laminations stack of ferromagnetic sheets into a housing, (b) protecting locations of the component module where coating is unwanted, (c) inserting the component module into a hermetic chamber receiving an ionized gas, (d) polarizing the component module to submit a fixed electric potential to the component module, (e) depositing a thin layer of protective coating on the laminations stack of ferromagnetic sheets through a method of Plasma Enhanced Chemical Vapor Deposition (PECVD) at a temperature lower than 150° C., (f) monitoring the deposition homogeneity and deposition thickness of the thin layer of protective coating until desired thickness, and (g) rectifying the surface of the thin layer of protective coating to have a uniform protective layer.
Abstract:
An electrical machine (20) coupled to a compressor (12) having a rotatable shaft (16), comprising: a rotor forming part of the rotatable shaft and having at least two magnetic portions (22A, 22B) separated by an inclined non-magnetic portion (24) and two elements (26A, 26B) of non-magnetic material at each end of the rotatable shaft, a stator comprising a laminated magnetic iron stack (28) surrounded by a winding (30) and disposed along a periphery of the rotor to define a first annular gap (32), a ring (34) of non-magnetic material disposed around the stator, and a casing (40) of magnetic material comprising permanent magnets (36), disposed around the non magnetic ring and having radial walls (40A, 40B) that project inwardly towards the rotor by defining a second annular gap (42) therebetween.
Abstract:
A modular motor and magnetic bearing assembly comprising a positioning casing having a plane reference surface, an outer cylindrical reference surface, a central portion provided on an outer face with cooling liquid flow channels, and intermediate portions provided with openings for gaseous fluid entry and exit; a rotor presenting an inner cylindrical reference surface and a plane reference surface; an electric motor; radial magnetic bearings; an axial abutment; and auxiliary mechanical bearings. The modular assembly can then be incorporated in a main casing simply by sliding and it can be connected directly to a functional unit without reworking adjustments of the magnetic bearings.
Abstract:
The present invention relates to a transmission belt providing a belt member, and at least one RFID tag attached to the belt member, the at least one RFID tag including an integrated circuit, and an antenna connected to the integrated circuit for transmitting a signal indicative of a state of the transmission belt. The signal indicative of the state of the transmission belt is determined on the basis of a current deflection of the antenna.
Abstract:
A device (17) for detecting the direction of rotation of a rotor for a magnetic bearing includes comparing means (100), first determining means (105), and second determining means (107). The comparing means (100) compares the speed of rotation of the rotor with a predefined speed threshold (Se). The first determining means (105) determines the speed of rotation gradient of the rotor. The second determining means (107) determines the direction of rotation of the rotor from the result of the comparison of the speed of rotation of the rotor with the predefined speed threshold (Se) and the value of the determined parameter representative of the kinetics of the rotor.
Abstract:
A transmission belt arrangement includes at least one transmission belt, at least one sensor configured to measure a parameter indicative of a surface mapping of the at least one transmission belt, and processing circuitry operatively connected to the at least one sensor and configured to determine a state of the at least one transmission belt based on the parameter indicative of the surface mapping.
Abstract:
Rotating machine vibration monitoring process for detecting degradations within a rotating machine providing an output axle fitted with magnetic bearings, the magnetic bearings having at least a position sensor and at least a magnetic actuator, the process provides the following steps: 1) defining a set of excitations that does not destabilizes the rotating machine, 2) injecting the set of excitations in the rotating machine through the magnetic actuators and 3) measuring the response of the rotating machine checking whether the response verifies at least one predefined criterium, 4) if it is not the case, adjusting the properties of the set of excitations and resuming the process at the injection step, 5) if the response verifies the at least one criterium, determining at least one condition indicator based on the response measured, 6) determining if an alarm is to be triggered based on the condition indicator determined.