Abstract: A system is for a machine having an alternating current (AC) power source with a first side and a second side, one or more windings, an AC polarity detector, a Hall effect device, two or more pairs of power switches, and a motor controller. The motor controller determines which of the power switches to open or close to obtain a direction of current flow through the one or more windings based on signals from the AC polarity detector and the Hall effect device.

Abstract: A system is for a machine having an alternating current (AC) power source with a first side and a second side, one or more windings, an AC polarity detector, a Hall effect device, two or more pairs of power switches, and a motor controller. The motor controller determines which of the power switches to open or close to obtain a direction of current flow through the one or more windings based on signals from the AC polarity detector and the Hall effect device.

Abstract: A system is for a machine having an alternating current (AC) power source with a first side and a second side, one or more windings, an AC polarity detector, a Hall effect device, two or more pairs of power switches, and a motor controller. The motor controller determines which of the power switches to open or close to obtain a direction of current flow through the one or more windings based on signals from the AC polarity detector and the Hall effect device.

Abstract: A method is for a machine having an alternating current (AC) power source with a first side (L1) and a second side (L2), two or more pairs of power switches, and one or more windings. The method comprises closing one pair of power switches by a control circuit to cause current to flow from a first side of the AC power source, through the one or more windings, and to the second side of the AC power source and closing another pair of power switches by the control circuit to cause current to flow from the second side of the AC power source, through the one or more windings, and to the first side of the AC power source.

Abstract: A method is for a machine having an alternating current (AC) power source with a first side (L1) and a second side (L2), two or more pairs of power switches, and one or more windings. The method comprises closing one pair of power switches by a control circuit to cause current to flow from a first side of the AC power source, through the one or more windings, and to the second side of the AC power source and closing another pair of power switches by the control circuit to cause current to flow from the second side of the AC power source, through the one or more windings, and to the first side of the AC power source.

Abstract: A multispeed alternating current (AC) machine circuit is for an AC power source having a first side and a second side. The AC machine circuit includes two or more pairs of power switches, one or more windings, and a control circuit to close one pair of power switches to cause current to flow from a first side of the AC power source, through the one or more windings, to the second side of the AC power source and to close the other pair of power switches to cause current to flow from the second side of the AC power source, through the one or more windings, to the first side of the AC power source.

Abstract: A multispeed alternating current (AC) machine circuit is for an AC power source having a first side and a second side. The AC machine circuit includes two or more pairs of power switches, one or more windings, and a control circuit to close one pair of power switches to cause current to flow from a first side of the AC power source, through the one or more windings, to the second side of the AC power source and to close the other pair of power switches to cause current to flow from the second side of the AC power source, through the one or more windings, to the first side of the AC power source.

Abstract: Devices and methods for producing mechanical vibration for the purpose of evaluating the durability or vibration response of a test article. More particularly, the devices and methods produce mechanical vibration of a test fixture without mechanical contact, thereby enabling the evaluation of the durability and vibration response of a test article connected to the test fixture. The device and method are particularly suitable for testing disk drives for portable computers and similar articles.

Abstract: A power supply device for providing uninterrupted power for a period of time is disclosed. The power supply device has a controller and a flywheel device. The flywheel device has a housing that contains a flywheel rotor and a motor/generator rotor. The flywheel rotor and the motor/generator rotor are mounted on a common shaft. An active axial magnetic bearing is located to support the shaft for frictionless rotation. The bearing provides support for the shaft, the flywheel rotor and motor/generator rotor. The axial magnetic bearing is attached to the housing and provides, in combination with the motor/generator rotor, a flux path and magnetic field to exert a magnetic force to lift the motor/generator rotor and the shaft on which it is mounted.

Abstract: A rotary motor and a rotary magnetic bearing are integrated in a compact assembly that is contact-less. A stator assembly surrounds a ferromagnetic rotor with an annular air gap which can accommodate a cylindrical wall, e.g. of a chamber for semiconductor wafer processing. The stator assembly has a permanent magnet or magnets sandwiched between vertically spaced magnetic stator plates with plural pole segments. The rotor is preferably a ring of a magnetic stainless steel with complementary pole teeth. The stator assembly (i) levitates and passively centers the rotor along a vertical axis and against tilt about either horizontal axis, (ii) provides a radial position bias for the rotor, and (iii) establishes a motor flux field at the rotor poles. Polyphase coils wound on the stator plates produce a rotating flux field that drives the rotor as a synchronous homopolar motor. A rotor without pole teeth allows operation with an asynchronous inductive drive.

Abstract: A rotary motor and a rotary magnetic bearing are integrated in a compact assembly that is contact-less. A stator assembly surrounds a ferromagnetic rotor with an annular air gap which can accommodate a cylindrical wall, e.g. of a chamber for semiconductor wafer processing. The stator assembly has a permanent magnet or magnets sandwiched between vertically spaced magnetic stator plates with plural pole segments. The rotor is preferably a ring of a magnetic stainless steel with complementary pole teeth. The stator assembly (i) levitates and passively centers the rotor along a vertical axis and against tilt about either horizontal axis, (ii) provides a radial position bias for the rotor, and (iii) establishes a motor flux field at the rotor poles. Polyphase coils wound on the stator plates produce a rotating flux field that drives the rotor as a synchronous homopolar motor. A rotor without pole teeth allows operation with an asynchronous inductive drive.