US 9,425,728 B2Granted

Dynamic power control for induction motors

AssigneeV Square/R LLC

InventorsLeo F. Valenti, James C. Daly, Thomas J. Valenti

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Abstract

An example electric motor including a conductive winding, a switching device, a rotor, and a controller is disclosed. The switching device is configured to selectively energize, by an AC source, a first portion of the conductive winding in a first state and a second portion of the conductive winding in a second state. The conductive winding generates a magnetic field having a first strength in the first state and a second strength in the second state. The rotor magnetically interacts with the magnetic field such that a torque is applied to the rotor. The amount of torque applied is related to the strength of the magnetic field. The controller is configured to: (i) determine a metric indicative of a load condition of the electric motor; and (ii) based on the determined metric, cause the switching device to switch between the first state and the second state one or more times.

Claims20

Dependent claims

An electric motor comprising:

a conductive winding including a plurality of turns, a first terminal, a second terminal, and a third terminal, wherein a first number of the plurality of turns are between the first terminal and the third terminal, a second number of the plurality of turns are between the second terminal and the third terminal, and the first number is different from the second number;
a switching device configured to selectively conduct power from the AC source to the first terminal in a first state and the second terminal in a second state, wherein, with the switching device in the first state, the conductive winding generates a first magnetic field responsive to the AC source conducting power to the first terminal, and wherein, with the switching device in the second state, the conductive winding generates a second magnetic field responsive to the AC source conducting power to the second terminal;
a rotor configured to magnetically interact with the first and second magnetic fields generated by the conductive winding such that a torque is applied on the rotor;
and
a controller configured to:
determine a metric indicative of a load condition of the electric motor;
and
based on the determined metric, cause the switching device to switch between the first state and the second state one or more times.

5 more elements

A method of regulating an amount of power delivered to a load via magnetic induction by a conductive winding comprising:

causing the conductive winding to generate a first magnetic field having a first strength by energizing a portion of the conductive winding from an alternating current (AC) source;
determining a metric indicative of a ratio of power between (i) power delivered to the conductive winding from the AC source and (ii) power consumed by the load;
determining that the metric is within a threshold range;
and
responsive to the determination that the metric is within the threshold range, causing the conductive winding to generate a second magnetic field having a second strength, wherein the first strength is different from the second strength.

2 more elements

An apparatus for regulating an amount of power provided to an electric motor comprising:

a switching device configured to selectively conduct power to a conductive winding of the electric motor from (i) a first AC source having a first voltage level in a first state and (ii) a second AC source having a second voltage level in a second state, wherein the first voltage level is different from the second voltage level, wherein, with the switching device in the first state, the conductive winding generates a first magnetic field having a first strength, wherein, with the switching device in the second state, the conductive winding generates a second magnetic field having a second strength, and wherein the first strength is different from the second strength;
a rotor configured to magnetically interact with magnetic fields generated by the conductive winding such that a torque is applied on the rotor;
and
a controller configured to:
determine a metric indicative of a ratio of power between power delivered to the conductive winding from the AC source and power consumed by the load;
determine that the metric is within a threshold range;
and
responsive to the determination that the metric is within the threshold range, cause the switching device to switch between the first state and the second state one or more times.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 14/931,368Filed 3 Nov 2015 · continuation in part
Priority: 12 Jun 2013
Published: US 2016/0056748 A125 Feb 2016
Granted: 23 Aug 2016
Term ends: Not estimatedThe source records don’t support an estimate.

Classification4 codes

H02P 25/18
Characterised by the circuit arrangement or by the kind of wiring: with arrangements for switching the windings, e.g. with mechanical switches or…
H02P 23/02
Arrangements or methods for the control of AC motors characterised by a control method other than vector control: specially adapted for optimising…
H02P 23/14
Arrangements or methods for the control of AC motors characterised by a control method other than vector control: estimation or adaptation of…
H02P
Control or regulation of electric motors, electric generators or dynamo-electric converters

Family

Application61/834,221Us provisional application · filed 12 Jun 2013
Application61/912,016Us provisional application · filed 5 Dec 2013
Application14/210,773Parent of this continuation-in-part · filed 14 Mar 2014
Application62/101,753Us provisional application · filed 9 Jan 2015
US 2016/0056748 A1Pre-grant publication · published 25 Feb 2016
US 9,397,603 B2Parent of this continuation-in-part
US 2014/0368093 A1Published application
US 9,425,728 B2This patent

From the US filing history. Foreign family members aren’t listed.