Harmonic Electromagnetic Torque Analysis of Turbo-Generators by a Novel Lumped Magnetic Parameter Method and Finite Element Method

Abstract–

Because of the absence of theoretical method for harmonic electromagnetic torque calculation, based on the relationship between the electromagnetic torque and the electromagnetic power, a new lumped magnetic parameter method (NLMPM) for harmonic electromagnetic torque calculation is introduced in this paper. Then based on the NLMPM, the effect of damper winding on harmonic component of the electromagnetic torque is investigated, including the existence of damper winding and the material alteration of damper winding. After that, to test the effectiveness of the theoretical analysis, the finite element models of a 1400MVA and a 30kVA turbo-generator are built up. Also, the experimental data proves the correctness of finite element models. The results achieved by the NLMPM and the finite element method (FEM) have a very good agreement. The concrete error between the NLMPM and the FEM at small current asymmetrical degree and big current asymmetrical degree is given respectively. The effect of damper winding on harmonic component of the electromagnetic torque is studied from a totally new perspective, as well. The theoretical method introduced in this paper can accurately help detect the harmonic electromagnetic torque vibration according to the lumped magnetic parameters.

Keywords:

• electromagnetic torque
• new lumped magnetic parameter method (NLMPM)
• damper winding
• finite element method (FEM)

Additional information

Funding

This work is supported by National major projects of science and technology in China (Calculation and analysis of magnetic field and electromagnetic force in negative sequence operation of large half speed turbo-generator) Grant 2009ZX06004-013-04-01, National Science Foundation of China under Grant 51677057, Basic scientific research project of universities in Heilongjiang province in 2019 Grant Hkdqg201908, Hkdxp201904 and Hkdxp201905, and Basic scientific research project of universities in Heilongjiang province in 2020 2020-KYYWF-0700.

Notes on contributors

Pin Lv

Pin Lv was born in Harbin in China, on November 8, 1989. She graduated from Harbin University of Science and Technology and got her master and doctor diploma there. Currently, she is working at Heilongjiang University of Science and Technology. Additionally, she is doing post-doctoral research at China University of Mining and Technology. She is specialized in electrical apparatus theoretical analysis, fault diagnosis and simulation calculation. She also has plenty knowledge about insulation calculation and smart-grids. Additionally, she is an expert at the new energy machines.

Xiaojie Wu

Xiaojie Wu was born in China, 1966. He got his master and doctor diploma in 1991 and 2000. From 2002 to 2004, he worked in the electrical engineering postdoctoral mobile station of the Department of electrical engineering, Tsinghua University. Currently, he works at China University of Mining and Technology as a professor and doctoral supervisor. He has undertaken or participated in more than 20 projects, including general projects of NSFC, Doctoral Program Fund of Ministry of education, national "863" key projects, national support plan and enterprise entrusted projects. He also won 1 second prize and 1 third prize of provincial and ministerial level scientific and technological progress. His main research field is motor control and protection, power electronics and power transmission.

Xunwen Su

Xunwen Su was born in China, 1976. He got his master and doctor diploma in 2005 and 2010 from North China Electric Power University. He did post-doctoral research at Harbin Institute of Technology from 2010 to 2014. Currently, he is currently working as Professor in Department of Electrical Engineering, Heilongjiang University of Science and Technology, Harbin, China. He has undertaken or participated in National Science Foundation of China projects. His research interests include modeling of wind farms, M-VSC-HVdc, and renewable energy generation.

Ying Yang

Ying Yang was born in China, 1976. She received M.S. degree in electrical engineering and the Ph.D. degree in electrical engineering from Harbin Institute of Technology and Harbin Engineering University in 2006 and 2014, respectively. Currently, she is working at Heilongjiang University of Science and Technology. She is mainly engaged in new energy micro grid modeling and control, underwater robot, nonlinear control and other related fields.

Xianhui Zhu

Xianhui Zhu received M.S. degree in electrical engineering from Harbin University of Science and Technology and the Ph.D. degree in electrical engineering from Harbin Institute of Technology, Heilongjiang, China, in 2006 and 2013, respectively. He is currently a lecturer in the College of Electrical and Control Engineering, Heilongjiang University of Science and Technology. His research interests include the areas of network reliability and control for renewable energy interface especially photovoltaic (PV), PV array configuration and PV system design.

Peng Lin

Peng Lin was born in China, 1983. He received M.S. degree in electrical engineering from Harbin University of Science and Technology and the Ph.D. degree in electrical engineering from Harbin University of Science and Technology, Heilongjiang, China, in 2009 and 2015, respectively. Currently, he is working at Harbin University of Science and Technology. He is mainly engaged in electrical apparatus theoretical analysis and fault diagnosis.