Elastic matrix determination method and vibration analysis method for laminated iron core

Patent metadata

Field	Value
Publication number	US-11513101-B2
Application number	US-201916960931-A
Country	US
Kind code	B2
Filing date	Jan 21, 2019
Priority date	Jan 24, 2018
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

An elastic matrix determination method and a vibration analysis method for a laminated iron core, with which it is possible to optimally determine an elastic modulus of a laminated iron core. When a vibration analysis of a laminated iron core obtained by laminating steel sheets is performed by using a configuration expression indicating a relationship between stress and strain in a matrix display by using an elastic matrix, a shear modulus in two surfaces including a laminating direction of the laminated iron core included in the elastic matrix in the configuration expression is determined in consideration of slip between laminated steel sheets.

First claim

The invention claimed is:

1. An elastic matrix determination method for a laminated iron core obtained by laminating steel sheets in a laminating direction, the method comprising:
creating an iron core for testing obtained by laminating steel sheets each using a same steel sheets as the laminated iron core in the laminating direction;
supporting a center of the created iron core for testing, and measuring an actual measurement value of a natural frequency by vibrating the created iron core for testing in the laminating direction;
estimating a relationship between a shear modulus in two planes of the iron core for testing and the natural frequency by performing a structural analysis plurality times using structural analysis software for the iron core for testing, the two planes being orthogonal to each other and extending in the laminating direction; and
determining the shear modulus from a relationship between the shear modulus and the natural frequency estimated by using the actual measurement value of the natural frequency.

2. The elastic matrix determination method according to claim 1 , wherein the laminated iron core is configured by laminating a plurality of electrical steel sheets.

3. The elastic matrix determination method according to claim 2 , wherein the laminated iron core is a laminated iron core for a transformer.

4. A vibration analysis method for a laminated iron core obtained by laminating steel sheets, the method comprising:
performing a vibration analysis of a laminated iron core by incorporating a shear modulus determined by the elastic matrix determination method according to claim 1 into an elastic matrix of a configuration expression in which a relationship between stress and strain is expressed by a tensor display using a response function.

5. The vibration analysis method for a laminated iron core according to claim 4 , wherein the laminated iron core is an iron core for a transformer, obtained by laminating a plurality of electrical steel sheets.

6. The elastic matrix determination method according to claim 1 , wherein the iron core for testing is a rectangular parallelepiped.

7. The elastic matrix determination method according to claim 1 , wherein the structural analysis is performed by taking, as a parameter, the shear modulus.

8. An elastic matrix determination method for a laminated iron core obtained by laminating steel sheets in a laminating direction, the method comprising:
forming an iron core for testing obtained by laminating steel sheets each using a same steel sheets as the laminated iron core in the laminating direction, and measuring an actual measurement value of a natural frequency by vibrating the iron core for testing in the laminating direction;
measuring a relationship between a shear modulus in two planes of the iron core for testing, an elastic modulus, and the natural frequency by performing a structural analysis plurality times, for the iron core for testing, the two planes being orthogonal to each other and extending in the laminating direction; and
determining the shear modulus and the elastic modulus from a relationship between the shear modulus, the elastic modulus, and the natural frequency measured by using the actual measurement value of the natural frequency.

9. A vibration analysis method for a laminated iron core obtained by laminating steel sheets, the method comprising:
performing a vibration analysis of a laminated iron core by incorporating a shear modulus and an elastic modulus determined by the elastic matrix determination method according to claim 8 into an elastic matrix of a configuration expression in which a relationship between stress and strain is expressed by a tensor display using a response function.

10. The vibration analysis method for a laminated iron core according to claim 9 , wherein the laminated iron core is an iron core for a transformer, obtained by laminating a plurality of electrical steel sheets.

11. The elastic matrix determination method according to claim 8 , wherein the laminated iron core is configured by laminating a plurality of electrical steel sheets.

12. The elastic matrix determination method according to claim 8 , wherein the structural analysis is performed by taking, as individual parameters, the shear modulus and the elastic modulus.

Assignees

• Jfe Steel Corp

Inventors

• Namikawa Misao
• Kijima Gou

Classifications

• G01N33/204 Primary

  Structure thereof, e.g. crystal structure · CPC title

• H01F41/0233

  Manufacturing of magnetic circuits made from sheets (magnetic cores made from sheets H01F27/245; soft magnetic alloys in the form of sheets H01F1/16) · CPC title

• G06F30/23

  using finite element methods [FEM] or finite difference methods [FDM] · CPC title

• G06F2119/14

  Force analysis or force optimisation, e.g. static or dynamic forces · CPC title

• G01N2291/26

  Scanned objects · CPC title