Energy-efficient asynchronous machine

Patent metadata

Field	Value
Publication number	US-11283383-B2
Application number	US-201816649646-A
Country	US
Kind code	B2
Filing date	Sep 20, 2018
Priority date	Sep 29, 2017
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

In a method for determining a flux of an asynchronous machine, the flux is adjusted according to a loss of the asynchronous machine. Therefore, an apparatus for determining the flux of the asynchronous machine is provided with a model for calculating a loss of the asynchronous machine according to the flux of the asynchronous machine. A selection facility selects a flux according to the loss.

First claim

The invention claimed is:

1. A method for determining a flux of an asynchronous machine, said method comprising:
setting the flux as a function of a loss of the asynchronous machine using a non-linear saturation characteristic curve;
determining the loss with a model; and
either reducing the flux below 100% or increasing the flux above 100%,
wherein the model has a thermal model.

2. The method of claim 1 , further comprising setting the flux with a minimal loss.

3. The method of claim 1 , further comprising optimizing efficiency of the asynchronous machine.

4. The method of claim 1 , further comprising setting the flux as a function of load.

5. The method of claim 1 , further comprising:
calculating a change in the loss as a function of a change in the flux, and
setting the flux as a function of the calculated loss.

6. The method of claim 1 , further comprising:
calculating the loss in a case of a current flux, the loss in a case of a reduced flux, and the loss in a case of an increased flux;
determining a minimum of a curve or of a function based on the calculated losses; and
setting the flux with minimal loss.

7. A device for determining a flux of an asynchronous machine comprising:
a thermal model for calculating a loss of the asynchronous machine as a function of the flux of the asynchronous machine; and
a selection facility for selecting the flux as a function of the calculated loss,
wherein the device is configured to set the flux as a function of the loss using a non-linear saturation characteristic curve and either reducing the flux below 100% or increasing the flux above 100%.

8. The device of claim 7 , further comprising an activation device for said device, said activation device activated as a function of load dynamics of the asynchronous machine.

9. The device of claim 7 , wherein the device is integrated in a rectifier.

10. The device of claim 7 , wherein the selection facility is configured to optimize efficiency of the asynchronous machine by the selection of the flux.

Assignees

• Siemens Ag

Inventors

• Nemeth-Csoka Mihaly

Classifications

• Y02P80/10

  Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier · CPC title

• H02P21/0089

  using field weakening · CPC title

• H02P21/02 Primary

  specially adapted for optimising the efficiency at low load · CPC title

• H02P21/12 Primary

  Stator flux based control involving the use of rotor position or rotor speed sensors · CPC title