| 摘要 |
This invention relates to the control of electrical machines and is concerned more particularly, though not exclusively, with the control of flux switching brushless permanent magnet and switched reluctance electrical machines without a mechanical shaft position sensor. Brushless Reluctance and permanent magnet motors can be used in many applications, since they do not require the use of commutators or brushes in supplying electrical power to the rotor of the motor. An electrical machine is provided for converting electrical energy into mechanical energy and/or mechanical energy into electrical energy, the machine comprising a stator and a rotor, the stator having one or more electrical windings wherein at least one electrical parameter of the windings have a cyclic variation related to rotor position; at least one control device for controlling supply of electrical current to or from the or each said electrical winding, and at least one rotor position sensor means for detecting at least one electrical signal related to the cyclic variation of at least one electrical parameter of the or each said electrical winding wherein at least one said rotor position sensor means comprises the steps of measuring the said electrical signal at least once during any part of a switching cycle, conversion of the at least one measured electrical signal to a ratiometric quantity representative of an estimate of the rotor position corresponding to the at least one measured electrical signal and using the said ratiometric quantity in a calculation to maintain the current passing through the or each said electrical winding in synchronism with rotor rotation. |
