Development of a low noise system to measure magnetostriction of grain oriented electrical steel under compressive stress

• Grant number: 20/13156-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2020
• End date: July 31, 2021
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Mateus Botani de Souza Dias
• Grantee: Paula David Padilha
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Power transformers are electrical machines that are used to reduce the energy losses at the power grid. Nowadays, the transformer noise is considered an environmental pollution; consequently, it raises the interest of some companies that produce electric steel and transformers. Although there are several factors that can produce this noise, its primary source is related to a magnetic property called magnetostriction, which corresponds to an elastic strain produced by the application of a magnetic field. Moreover, the transformer cores are submitted to compressive stresses during the operation, increasing magnetostriction and noise. Therefore, the magnetostriction study of grain oriented electrical steel under compressive stresses is a concern of the scientific community and companies in the energy sector, such as APERAM and ABB. This project has the goal to improve the performance of the magnetostriction measure system, reducing the amount of noise produced. In order to meet this target, the measurement system will be developed using a full Wheatstone bridge type III. Moreover, this new measure system will be used to evaluate the compressive stress effects on the magnetic properties of coated grain oriented electrical steel, since this condition is close to transformer operation. In summary, the development of a low noise system to measure magnetostriction will improve the quality of our research group, placing us close to the technological level of some international research centers. Besides that, the grain oriented electrical steel companies are very concerned about this subject and it could be crated a partnership between private enterprise and university.