Abstract: An electric machine comprising a power supply and an electrically excited synchronous machine is provided. The electrically excited synchronous machine comprises a stator with stator windings and a rotor with a plurality of rotor poles, wherein the rotor has a magnetic field knee region and rotor field windings around the plurality of rotor poles. A power converter is coupled between the power supply and the electrically excited synchronous machine. The power converter is arranged to provide a pulsed operation by providing a pulsed current to the stator windings and a pulsed DC current to the rotor field windings, wherein the pulsed DC current continuously provides a magnetic field in the rotor.

Abstract: An electric machine, comprising a power supply and an electrically excited synchronous machine is provided. The electrically excited synchronous machine comprises a stator with stator windings, a rotor, comprising rotor poles with field windings and a plurality of permanent magnets magnetically connected to the rotor pole. A power converter is coupled between the power supply and the electrically excited synchronous machine, the power converter is arranged to provide a pulsed operation by providing a pulsed AC current to the stator windings and a pulsed DC current to the rotor field windings, wherein the pulsed DC current to the rotor field windings causes the rotor poles to have a magnetic orientation that has a same magnetic orientation as the permanent magnets magnetically connected to the rotor poles.

Abstract: A method of controlling an electric machine having a separately excitable rotor and stator includes pulsing the electric machine and controlling the electric machine to an OFF state. Pulsing the electric machine includes exiting the rotor with direction current and the stator with a stator biasing current at the same time to generate magnetic flux in the rotor via two separate paths. Pulsing the electric machine may also include terminating the stator basing current when a desired magnetic flux is generated in the rotor. Pulsing the electric machine may include proving a stator flux to the stator such that the electric machine provides a pulse torque.

Abstract: A method of braking for a vehicle with a multi-phase electric motor, said motor including at least one stator group including a first stator arrangement and a second stator arrangement, each arrangement including three coils, each arrangement connected to respective low side and/or high side circuitry, each low side and/or high side circuitry including respective low side switches and high side switches, said method including: for either of said second or first arrangements, i) setting any two of said switches in said low side circuitry to a closed state and the other switch in an open state, and setting all the switches in the high side to an open state; and/or ii) setting any two of said switches in said high side circuitry to a closed state and setting the other switch to an open state, and setting all the switches on the low side to an open state.

Abstract: A method of controlling an electric machine having a separately excitable rotor and stator includes pulsing the electric machine and controlling the electric machine to an OFF state. Pulsing the electric machine includes exiting the rotor with direction current and the stator with a stator biasing current at the same time to generate magnetic flux in the rotor via two separate paths. Pulsing the electric machine may also include terminating the stator basing current when a desired magnetic flux is generated in the rotor. Pulsing the electric machine may include proving a stator flux to the stator such that the electric machine provides a pulse torque.

Abstract: An electric machine is provided. A power converter is coupled between a power supply and a wound field synchronous machine. The power converter is arranged to provide a pulsed operation by providing a pulsed DC current to field windings of the wound field synchronous machine.

Abstract: A method of braking in an electrically powered vehicle, said vehicle including a drive system which includes a multi-phase motor electric motor, said motor comprising at least one stator group; said stator group comprising a first stator arrangement including three coils (e2, e4, e6) and a second stator arrangement including threes coils, (e2* e4* e6*) being angularly offset from said first coil arrangement, and where, said first arrangement is connected to respective low side and/or high side circuitry, including a low side switches (32, 34, 36) and/or high side switches (31, 33, 35) for each of the said coils respectively, adapted to selectively allow current to flow through said respective coils of said first stator arrangement from a power source, and where said second arrangements is connected to respective low side and/or high side circuitry, including a low side switches (32*, 34, *36*) and/or high side switches (31*, 33*, 35*) for each of the said coils respectively, adapted to selectively allow curre

Abstract: A cam drive apparatus comprising a magnetic gear adapted to communicate rotational movement between a crankshaft and a cam shaft, wherein said magnetic gear comprises an outer member comprising a plurality of circumferentially spaced magnet means, said outer member being mounted for rotation with one of said crankshaft and camshaft, an inner member comprising a plurality of circumferentially spaced magnet means, said inner member being concentrically arranged within said outer member to define an annular gap therebetween, and an intermediate member comprising a plurality of circumferentially spaced ferromagnetic pole.pieces located within said annular gap between said inner and outer members and being mounted for rotation with the other of said crankshaft and camshaft.