Multi-phase wound rotor resolver apparatus
View Patent ↗A novel multi-phase resolver topology and apparatus is provided for measuring a displacement of movement body more precisely and economically. In variable reluctance (VR) resolvers, N coil-poles are placed at N equally spaced positions over one turn of the stator, N being an odd number greater than or equal to 5. Each coil serves both as an excitation and a sensing coil, and all N coils are wound with the same number of turns at an identical electrical polarity. Depending on the installed rotor lobe shape, N sinusoidal or quasi-square waveform displacement signals are sensed on multi-phase resolver, and from which two-phase orthogonal displacement signals are optimally and differentially synthesized. The multi-phase resolver topology and differential synthesis method is also applied to other types of resolvers, such as wound-rotor, inductance, capacitive, and magnetic resolvers.
1. A multi-phase wound-rotor (WR) resolver apparatus for measuring a displacement position of a circular movement body, the multi-phase WR resolver apparatus comprising:
a stator including:
an N number of coils placed and wound independently of one another at N equally divided positions over a mechanical or an electrical period of the stator, N being an odd number greater than or equal to 5,
wherein the N number of coils have an identical electrical polarity, are each wound with an equal number of winding turns, and sense a displacement of the rotor; and
a wound-rotor, wherein a coil is wound with a sinusoidally distributed winding, a driving signal carrier is applied to the coil wound on the wound-rotor, and one or more periods of sinusoidal electrical signals are induced on each of the N number of coils on the stator per one turn of the wound-rotor such that N sequentially phase-delayed and amplitude-modulated displacement signals are sensed from the N number of coils on the stator.
2. The multi-phase WR resolver apparatus of claim 1 ,
wherein each of the N number of coils is subdivided into two sensing-coils on the stator,
wherein the two sensing-coils are located at 180° difference in mechanical or electrical angle on the stator,
wherein the two sensing-coils have an opposite electrical polarity, and are serially connected such that the N number of sequentially phase-delayed and amplitude modulated displacement signals are obtained from N sets of two subdivided sensing coils.
3. The multi-phase WR resolver apparatus of claim 2 ,
wherein the two sensing-coils are placed at a dual stator on a shared axis, wherein the dual-stator includes a stator-A and a stator-B on a shared axis,
wherein the two sensing-coils are separately placed on the stator-A and the stator-B at a same electrical angle position, with an opposite electrical polarity, and are serially connected,
wherein a phase-delayed displacement signal, free of a common mode noise induced from a directional external magnetic flux toward the resolver, is attained through the two sensing-coils on the dual stator and wherein the N number of sequentially phase-delayed and amplitude modulated displacement signals are obtained from N sets of the two sensing coils on the dual stator.