Valeo Electrical Systems, Inc.

Revolution Motor Technology, LLC

Sergei Kolomeitsev

John Riden Suriano

Joseph P Whinnery

Hong Jiang

Thomas James Gallagher

Craig A Ham

A polyphase electric motor has a rotor, a stator with a plurality of slots, a plurality of main windings and a plurality of auxiliary windings installed in slots of the stator, and a main winding and an auxiliary winding that correspond to a selected phase of an alternating current power source. The auxiliary windings are connected to the motor terminals through a plurality of capacitors, and the auxiliary windings and corresponding capacitors are connected in parallel to the main windings. The main winding and the auxiliary winding of the selected phase are offset by about 60 to about 120 electrical degrees. A power of the plurality of main windings is at least 75% of a power of the polyphase electric motor at full load rating and the power of the plurality of main windings is motoring at 25% of the full load rating.

Polyphase electric motor

A polyphase electric motor has a rotor, a stator with a plurality of slots, a plurality of main windings and a plurality of auxiliary windings installed in slots of the stator, and a main winding and an auxiliary winding that correspond to a selected phase of an alternating current power source. The auxiliary windings are connected to the motor terminals through a plurality of capacitors, and the auxiliary windings and corresponding capacitors are connected in parallel to the main windings. The main winding and the auxiliary winding of the selected phase are offset by about 80 to about 100 electrical degrees. A power of the plurality of main windings is at least 75% of a power of the polyphase electric motor at full load rating and the power of the plurality of main windings is motoring at 25% of the full load rating.

A fault-handling system for a 2-phase motor. When an electric motor is used for power assist in a steering system in a vehicle, malfunctions can cause loss of assist, and detectable vibration. The invention utilizes a 2-phase motor in such an application, and implements alternate modes of operation when certain malfunctions occur, thereby maintaining the assist function in situations wherein the function would otherwise be lost or reduced.

Fault-handling system for electric power steering system

An apparatus and method for controlling sinusoidal currents in inductive loads during zero-crossing to reduce distortion. The apparatus and method utilizes first and second PWM signals during a single PWM cycle to apply opposite voltage signals to obtain a net desired voltage across the inductive load. The voltage applied to the load is compared with a threshold and, when the applied voltage is greater than the threshold, normal PWM signals are applied to the load, and when the applied voltage is less than the threshold, an adjusted voltage formed of first and second PWM signals is applied to the load.

Zero-crossing correction in sinusoidally commutated motors

A control system for an electric motor. Field Oriented Control, FOC, uses a digital control system, and attempts to maintain the rotating stator magnetic field ninety degrees ahead of the rotor field, in order to maximize torque. However, if a three-phase motor is used, which is very common, large amounts of computation are required, to convert from a three-phase coordinate system to an orthogonal coordinate system. The invention replaces the three-phase motor with a two-phase motor, which has been found to impose certain additional costs, but also provides benefits.

Electric power steering system for a vehicle

Torque generating apparatus and method for automotive applications. A brushless DC motor is design optimized to operate at a design voltage, Vs, along an optimal speed/torque profile. A DC/DC converter is provided for supplying power at an alternate voltage, Va, to enable motor operation at speed/torque combinations not on the optimal profile. A switch is provided to enable the motor to be operated selectively at either of the two voltages.

Apparatus and method for generating torque

A segmented stator for a permanent magnet motor. The stator includes a plurality of stator segments forming an annular stator yoke and a plurality of stator teeth extending from an edge of the stator yoke. At least one coupling is between adjacent stator segments and shaped to allow movement of adjacent teeth in a so-called loose tooth design. Slot wedges are located between adjacent teeth to prevent the conductive windings from moving out of the slots through the slot openings. The slot wedges also prevent movement of adjacent teeth with respect to one another. The segmented stator can comprise an annular yoke with a plurality of discrete teeth or a plurality of assemblies including a rim section and a tooth section. The slot wedges can be keyed wedges that maintain their position through interlocking and/or can be integrated with a stator bobbin.

Stator design for permanent magnet motor with combination slot wedge and tooth locator

A rotor for a permanent magnet motor with a rotor yoke and a permanent magnet ring mounted on the rotor yoke, the magnet ring having a plurality of circumferentially spaced poles. One of the rotor yoke and the permanent magnet ring is an annular member including depressed portions along a peripheral edge located around a midpoint between each pole. The depressed portions are shaped so the motor produces a sinusoidal flux density. The other of the rotor yoke and the permanent magnet ring is an annular ring. In another aspect, the rotor has a rotor yoke and a permanent magnet ring mounted on the rotor yoke. The permanent magnet ring includes a plurality of circumferentially spaced poles. One of the rotor yoke and the permanent magnet ring includes a plurality of depressions along an outer peripheral edge shaped so the motor produces a sinusoidal flux density during operation. Each of the plurality of depressions is located around a junction defined by two poles. In either aspect, the rotor yoke can be skewed, and the magnet ring can be tapered.

Magnet shaping and pole concentration for reduction of cogging torque in permanent magnet motors

A stator tooth design for a stator core of a permanent magnet motor. The tooth surface comprises a plurality of surface segments, wherein each surface segment of the plurality of surface segments joins an adjacent surface segment of the plurality of surface segments at an obtuse angle, preferably between 160 and 170 degrees. Alternatively, the tooth surface comprises a single essentially straight surface segment. Each of the plurality of surface segments has a starting edge and an ending edge. Preferably, the starting edge of a surface segment lies along a first circumferential path a predetermined radial distance from the outside edge of the stator core and the ending edge of the surface segment lies along a second circumferential path either closer to or further from the outside edge. The first circumferential path and the second circumferential path can be concentric to the outside edge of the stator core.

Growing community of inventors

Rochester, MI, United States of America

Sergei Kolomeitsev