Nidec Motor Corporation

Eric Coupart

John G Schrader

Ryan M Bastien

Bret S Clark

Cheng-Tsung Liu

Richard A Belley

James D Ellis, Ii

Timothy R Albers

Pranesh Rao

Michael L McClelland

Guo-Jhih Yan

Pei-Chun Shih

Sheng-Chan Yen

Yu-Wei Hsu

Ta-Yin Luo

A variable frequency drive motor system and method with a single variable frequency drive controller controlling multiple synchronous reluctance motors in an open-loop mode using volts-per-Hertz control. Each motor includes a rotor including three or more curved, spaced-apart barrier slots extending longitudinally through each quadrant of the rotor. The rotor also includes a conductive cage including a plurality of conductive rotor bars contained within the barrier slots and also extending longitudinally through each quadrant, and conductive end rings located at opposite ends of the rotor and electrically connected to the respective ends of the rotor bars. The controller controls speed and torque by varying input frequency and voltage in an open-loop mode by adjusting the voltage magnitude of an inverter's output to each motor to match a required load torque in a volts-per-Hertz relationship. An operator interface allows for starting, stopping, adjusting, and otherwise controlling the operation of each motor.

Variable frequency drive synchronous reluctance motor system with volts-per-Hertz control

A dual motor system includes a first motor providing a lower speed range and a second motor providing a higher speed range, wherein the motors are coaxially arranged and aligned on and drive a common shaft, and a motor control system controlling the speed of the first motor and engaging the second motor as needed. The first motor is a variable speed motor providing a lower two-thirds of a full speed range, and the second motor is an induction motor providing the upper one-third in the form of one or more discrete fixed speeds. The system may include a transformer including a first winding tap which provides a first higher speed, and a second winding tap which provides a second higher speed. The system may also include a flow control system for automatically controlling the speed of the motors for particular applications, such as flow control in a pool.

Dual motor system with flow control

Dual motor system

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Clayton, MO, United States of America

Eric Coupart