Field winding rotating electrical machine and method for controlling field current of a field winding rotating electrical machine

US9294025B2 · US · B2

Patent metadata
FieldValue
Publication numberUS-9294025-B2
Application numberUS-201214386077-A
CountryUS
Kind codeB2
Filing dateMay 15, 2012
Priority dateMay 15, 2012
Publication dateMar 22, 2016
Grant dateMar 22, 2016

How to read this patent

A practical reading order for non-experts. Skip the full description unless you need deep technical detail.

  1. Title

    What the patent document calls the invention.

  2. Abstract

    A short plain-language summary of the technical disclosure.

  3. Assignees and inventors

    Who owns or filed the patent and who is credited as inventor.

  4. Key dates

    Filing, priority, publication, and grant dates set the timeline.

  5. First independent claim

    The legal scope of protection — read this for what is actually claimed.

  6. CPC / IPC classifications

    Technology tags used to group this patent with similar filings.

  7. Citations and related patents

    Prior art links and similar publications in this corpus.

Abstract

Official abstract text for this publication.

A field winding rotating electrical machine includes a field current detection section, a field current control section configured to calculate a duty ratio of a current supplied to the field winding based on a field current detection value, to thereby control current supply to the field winding by using a switching element, and a field current correction section configured to estimate a time point when the field current becomes 0 A based on a control state of the field current, to specify the field current detection value at the estimated time point to be a field current correction value, and to subtract the field current correction value from the field current detection value, to thereby calculate the corrected field current value. The field current control section controls the current supply based on the corrected field current value calculated by the field current correction section.

First claim

Opening claim text (preview).

The invention claimed is: 1. A field winding rotating electrical machine, comprising: an armature winding; a field winding; a field current detection section configured to detect a field current flowing in the field winding; a field current control section configured to calculate a duty ratio of a current supplied to the field winding based on a field current detection value detected by the field current detection section, to thereby control current supply to the field winding by using a switching element; and a field current correction section configured to estimate a time point when the field current becomes 0 A based on a control state of the field current, to specify the field current detection value detected by the field current detection section at the estimated time point to be a field current correction value, and to subtract the specified field current correction value from the field current detection value detected by the field current detection section, to thereby calculate the corrected field current value, wherein the field current control section controls the current supply based on the corrected field current value calculated by the field current correction section. 2. A field winding rotating electrical machine according to claim 1 , wherein the field current correction section estimates a time point when a state where the duty ratio calculated by the field current control section is zero, which corresponds to the control state of the field current, continues for a predetermined time period to be the time point when the field current becomes 0 A, and specifies the field current correction value. 3. A field winding rotating electrical machine according to claim 2 , wherein the predetermined time period used by the field current correction section is set to a value based on a time constant of the field winding. 4. A field winding rotating electrical machine according to claim 3 , further comprising a temperature detection section configured to detect ambient temperature of the field current detection section, wherein the field current correction section stores the ambient temperature detected by the temperature detection section when the field current correction value is specified as ambient temperature of the correction, wherein when the ambient temperature detected by the temperature detection section is within a predetermined range from the ambient temperature of the correction, the field current correction section avoids specifying the field current correction value, and wherein when the ambient temperature detected by the temperature detection section is outside the predetermined range from the ambient temperature of the correction, the field current correction section specifies the field current correction value. 5. A field winding rotating electrical machine according to claim 2 , further comprising a temperature detection section configured to detect ambient temperature of the field current detection section, wherein the field current correction section stores the ambient temperature detected by the temperature detection section when the field current correction value is specified as ambient temperature of the correction, wherein when the ambient temperature detected by the temperature detection section is within a predetermined range from the ambient temperature of the correction, the field current correction section avoids specifying the field current correction value, and wherein when the ambient temperature detected by the temperature detection section is outside the predetermined range from the ambient temperature of the correction, the field current correction section specifies the field current correction value. 6. A field winding rotating electrical machine according to claim 1 , wherein in a case where a control mode includes: as the control modes, one or more operation modes, to which the mode transits in accordance with an operation command sent from outside; and a halt mode in which current supply control to the armature winding and the field winding is not performed, the field current correction section estimates a time point when one of a state where the control mode is not one of the operation mode and the halt mode and a state of the halt mode as the control state of the field current continues for a predetermined time period to be the time point when the field current becomes 0 A, and specifies the field current correction value. 7. A field winding rotating electrical machine according to claim 6 , wherein the predetermined time period used by the field current correction section is set to a value based on a time constant of the field winding. 8. A field winding rotating electrical machine according to claim 7 , further comprising a temperature detection section configured to detect ambient temperature of the field current detection section, wherein the field current correction section stores the ambient temperature detected by the temperature detection section when the field current correction value is specified as ambient temperature of the correction, wherein when the ambient temperature detected by the temperature detection section is within a predetermined range from the ambient temperature of the correction, the field current correction section avoids specifying the field current correction value, and wherein when the ambient temperature detected by the temperature detection section is outside the predetermined range from the ambient temperature of the correction, the field current correction section specifies the field current correction value. 9. A field winding rotating electrical machine according to claim 6 , further comprising a temperature detection section configured to detect ambient temperature of the field current detection section, wherein the field current correction section stores the ambient temperature detected by the temperature detection section when the field current correction value is specified as ambient temperature of the correction, wherein when the ambient temperature detected by the temperature detection section is within a predetermined range from the ambient temperature of the correction, the field current correction section avoids specifying the field current correction value, and wherein when the ambient temperature detected by the temperature detection section is outside the predetermined range from the ambient temperature of the correction, the field current correction section specifies the field current correction value. 10. A field winding rotating electrical machine according to claim 1 , wherein in a case where a vehicle equipped with an idle stop system performs field current control, the field current correction section estimates a time point when a state where the vehicle performs idle reduction, which corresponds to the control state of the field current, continues for a predetermined time period to be the time point when the field current becomes 0 A, and specifies the field current correction value. 11. A field winding rotating electrical machine according to claim 10 , wherein the predetermined time period used by the field current correction section is set to a value based on a time constant of the field winding. 12. A field winding rotating electrical machine according to claim 11 , further comprising a temperature detection section configured to detect ambient temperature of the field current detection section, wherein the field current correction section stores the ambient temperature detected by the temperature detection section when the field current correction value is specified as ambient temperature of the correction, wherein when the ambient temperature detected by the

Assignees

Inventors

Classifications

  • H02P7/282Primary

    controlling field supply only · CPC title

  • H02P9/30Primary

    using semiconductor devices · CPC title

  • Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode · CPC title

  • Cross-Sectional Technologies · mapped topic

  • Cross-Sectional Technologies · mapped topic

Patent family

Related publications grouped by family.

External sources

Frequently asked questions

Answers are generated from the same data shown on this page.

What does patent US9294025B2 cover?
A field winding rotating electrical machine includes a field current detection section, a field current control section configured to calculate a duty ratio of a current supplied to the field winding based on a field current detection value, to thereby control current supply to the field winding by using a switching element, and a field current correction section configured to estimate a time p…
Who is the assignee on this patent?
Akita Kenichi, Mori Masato, Tabata Mitsunori, and 1 more
What technology area does this patent fall under?
Primary CPC classification H02P7/282. Mapped technology areas include Electricity.
When was this patent published?
Publication date Tue Mar 22 2016 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
What related patents are in patentsdb?
We list 8 related publications on this page (citations in our corpus or others sharing the same primary CPC).