Patent ID: 8022649
Filing Date: 2011-09-20
Classification: H02P

Abstract:
1. An electrical machine for converting electrical energy into mechanical energy and/or mechanical energy into electrical energy, the machine comprising: a rotor having a plurality of rotor poles; a stator for rotatably receiving said rotor and having (i) at least one field magnet device for generating a first magnetomotive force between said rotor and said stator and including at least one first electrical winding, and (ii) at least one armature magnet device including at least one second electrical winding adapted to carry electrical current varying in synchronism with rotation of said rotor relative to said stator to generate a second magnetomotive force having a component transverse to said first magnetomotive force; at least one control device for controlling supply of electrical current to or from the or each said second electrical winding; and at least one rotor position sensor device for detecting at least one electrical signal related to the rotational position of the rotor relative to the stator and induced in a respective said first or second electrical winding as a result of a current passing through a respective second or first electrical winding, wherein at least one said rotor position sensor device comprises at least one divider device for (i) receiving at least one first electrical input signal related to the rate of change of current in at least one said first or second winding, (ii) receiving at least one respective second electrical input signal related to the voltage across at least one respective said second or first winding, current through which causes at least part of at least one said first electrical input signal, and (iii) providing to at least one said control device at least one respective control signal related to the ratio of at least one said first electrical input signal and at least one said second electrical input signal.