Nidec Sr Drives, Ltd

Switched Reluctance Drives Limited

Paul Andrew Sykes

Michael James Turner

Phillip George Dickinson

Norman Neilson Fulton

Michael Paul Tankard

Ian Jordison

Thilak Raj Durairaj

A controller for a switched reluctance machine is operated to close a switch which would otherwise be open so as to connect a phase winding to the DC link to which the winding is connected during other parts of the electrical cycle. This produces a condition which allows the insulation of the system to be monitored by applying a voltage between the DC link and ground.

Method of operating a switched reluctance machine

A rotating electrical machine has a rotor composed of laminations having salient poles. The poles have one or more holes which are positioned so as to reduce the peak stress experienced by the laminations when the rotor is rotating. The holes are chosen according to a disclosed design procedure which gives a reduction in peak stress for a given limit on the output of the machine.

Reducing stress in electric-machine rotors by optimizing holes

A switched reluctance machine has an array of poles attached to a stationary holding member to form a stator. The stator has no back-iron. The machine has two arrays of rotor poles, positioned on either side of the stator poles, and circumferentially aligned with each other. When a pair of rotor poles is aligned with a stator pole, a small airgap is formed at each end of the stator pole, across which flux can be driven to produce torque in a rotary arrangement or force in a linear arrangement. When the poles are in the unaligned position, the phase inductance is very low.

Electrical machine with dual radial airgaps

A switched reluctance drive is supplied from a power source. The phases of the machine are controlled by a current controller which uses an excitation strategy to minimize the supply current drawn for a particular output. The strategy alternates the excitation between two phases for a given time until the rotor moves to a desired position. A method of starting a switched reluctance motor having a stator with at least two phases, a moveable part, and a position transducer includes determining from transducer output a plurality of phases that are available to produce force in a desired direction, energizing a first phase of the available phases for a predetermined time period that is independent of the transducer output, and energizing a second phase of the available phases after energization of the first phase is initiated.

Excitation of switched reluctance motors

A power train controller can operate in either motoring or braking modes. Its prime mover accepts a limited proportion of braking power and the remainder of the braking power is dissipated in an energy dump. A control system is arranged to maintain the voltage bus of the power train at a constant value throughout both modes.

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Leeds, United Kingdom

Paul Andrew Sykes