Patent Application
20190206614
An apparatus for phase-shifting sinusoidal commutation.
An apparatus for motor commutation is well known to consist of a stator system, a rotating shaft being rotatably mounted in the stator system, one or more rotor magnets, having a magnetic field with a magnetic polarization, being affixed to the rotating shaft such that the rotor magnet's magnetic polarization is not parallel with the rotating shaft's axis of rotation. One or more stator phases are also necessary—each stator phase consisting of electromagnets having electrical leads at opposing ends of windings of insulated electrically conductive material, one lead being electrically continuous with the other, that are mechanically affixed to the stator system and disposed about the rotor magnet(s) to deliver an electromagnetic force onto the rotor magnet(s) when electric current is applied to the stator phases.
A shaft sinusoid generating circuit, having output terminals which are connected to electrical components that generate an electrical signal having sinusoidal form whose instantaneous frequency is commensurate with the instantaneous frequency of the rotating shaft's angular displacement, is also well established in the prior art in such technologies as magneto-resistive sensors.
Prior art, apparently disjoint from motor commutation technology, also consists of phase-shifting circuits being formed of input terminals, output terminals and electrical circuitry which generates a phase-shifted version of the signal applied to its input terminals at its output terminals.
This invention employs a phase-shifting and control circuit being formed of input terminals, output terminals, and electrical components generating current capable of causing a magnetic field in a motor's stator phases to cause its rotating shaft to rotate when the stator phases are connected to the output terminals of a phase-shifting and control circuit. The phase-shifting and control circuit routes the signal of a shaft sinusoid generating circuit through one or more phase-shifting circuit(s) which is in turn amplified and otherwise conditioned prior to being supplied to one or more of the stator phases.
The purported optimal means of commutating a motor is achieved by employing sinusoidal commutation which is reported to provide smooth torque and linear motion control similar to brushed motors without the disadvantages of brushed commutation. Unfortunately, present implementations of sinusoidal commutation do not work well for motors spinning at high speeds. This deficit has generated other techniques such as space-vector modulation which utilizes complex computational algorithms.
The invention in its broadest aspect provides for motor commutation achieved via phase-shifting technology.
Other advantages of the present invention will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
Referring to the
The apparatus includes a stator system having three electrical coils—each coil acting as a first, second and third electrical phase. A rotating shaft is rotatably mounted within the stator system; the stator system generates magnetic fields that act on a rotor magnet which is mechanically affixed to the rotating shaft. The rotor magnet can be an electromagnet formed of windings of electrically conductive material having two leads at opposing extremes each being electrically continuous with the other forming its input terminals. The rotor magnet is affixed to the rotating shaft. The rotor magnet is mechanically affixed on the rotating shaft at the intersection of the rotating shaft and the plane formed from the electrical phases which are dispersed with angularly equidistant spacing about the rotor electromagnet at right angles to the rotating shaft.
The primary basis of this invention is a shaft sinusoid generating circuit having output terminals which are connected to electrical components generating an electrical signal having sinusoidal form whose instantaneous frequency is commensurate with the instantaneous frequency of the rotating shaft's angular displacement. The second basis of the invention is found in a phase-shifting circuit that is formed of input terminals, output terminals and electrical circuitry which generates a phase-shifted version of the signal applied to the phase-shifting circuit's input terminals at its output terminals. The technology underlying the phase shifting circuit is a well-known clement in the state of the art as described in such teachings as U.S. Pat. No. 4,122,364 A and in: Poon and Taghivand. Supporting and Enabling Circuits for Antenna Arrays in Wireless Communications, Proceedings of the IEEE, Vol 100, No. 7, pp 2207-2218, July 2012 (DOI 10.1109/JPROC.2012.2186949).
Each electrical phase is excited by a phase-shifting and control circuit being formed of input terminals, output terminals, and electrical components generating an amplified, electrically conditioned and phase-shifted version of the signal generated from the shaft sinusoid generating circuit having current capable of causing a magnetic field in the stator phases to cause the rotating shaft to rotate when an electromagnetic field is present on the rotor magnet. To generate a phase shift, the phase-shifting and control circuit is constituted in part by one or more phase-shifting circuits.
A voltage command line is configured to receive a voltage level indicating a command for the stator phases to apply an electromagnetic force to the rotor magnet's electromagnetic field which is also initiated by voltage applied on the voltage command line.
Obviously, many modifications and variations of the present invention are possible in light of the above teachings and may be practiced otherwise than as specifically described while within the scope of the appended claims. That which is prior art in the claims precedes the novelty set forth in the “characterized by” clause. The novelty is meant to be particularly and distinctly recited in the “characterized by” clause whereas the antecedent recitations merely set forth the old and well-known combination in which the invention resides. These antecedent recitations should be interpreted to cover any combination in which the inventive novelty exercises its utility. The use of the word “said” in the apparatus claims refers to an antecedent that is a positive recitation meant to be included in the coverage of the claims whereas the word “the” precedes a word not meant to be included in the coverage of the claims. In addition, the reference numerals in the claims are merely for convenience and are not to be read in any way as limiting.
This application claims the benefit of the provisional application Ser. No. 62/437,644 filed 21 Dec. 2016.
