Extra Freedom Degrees of Six-Phase Induction Motors Used to Diagnose Stator Inter-Turn Faults

Abstract—

Multi-phase electrical machines have recently drawn growing attention and usage, among which, 6-phase induction motors (6PIMs) have gained an important part. They are main candidates to be utilized in the oil and gas industries, hot rolling mill drives, pumps, ship propulsion, and traction. Condition monitoring and fault diagnosis are essential technologies, which enable incipient fault detection and removal in order to prevent serious damages to the machines and catastrophic interrupt of them. Among the incipient faults, the stator winding inter-turn fault is a rather frequent one. In recent decades, numerous studies have dealt with this fault in three-phase induction motors, however, a few reports are available concerning 6PIMs. This paper applies the winding function method to model and simulate the 6PIM with inter-turn fault in a stator phase winding. Then, using the extra degrees of freedom in 6PIM, an analytical method is used to define an efficient index for detecting the stator inter-turn faults. This index also identifies the faulty phase of the stator, shows good sensitivity to the fault severity and is almost insensitive to the load torque change. Various simulation studies and corresponding experimental test results confirm effectiveness of the proposed index.

Keywords:

• extra degrees of freedom
• fault diagnosis
• faulty phase identification
• six-phase induction motor
• stator winding
• inter-turn fault

Additional information

Notes on contributors

Hassan Baghgar Bostan Abad

Hassan Baghgar Bostan Abad received the B.S. degree in Electronics Engineering from the Amirkabir University of Technology, Tehran, Iran in 1999 and the M.S. degree in Electrical Power Engineering from Tarbiat Modares University, Tehran, Iran in 2003. Then, he joined to the Islamic Azad University, Myaneh, Iran as a Faculty Member. Currently, Mr. Baghgar is working toward the PhD in the University of Zanjan, Iran. His research interests include modeling, simulation, and fault diagnosis of electrical machines and drives.

Mansour Ojaghi

Mansour Ojaghi received the B.Sc. degree from Shahid Chamran University, Ahwaz, Iran in 1993, the M.Sc. degree from the University of Tabriz, Tabriz, Iran in 1997, and the Ph.D. degree from the University of Tehran, Tehran, Iran, in 2009 all in Electrical Engineering. He was with the Zanjan Regional Electricity Company for 10 years, where he held the position of Manager of Grid Technical Office. After receiving the Ph.D., Dr. Ojaghi joined the Department of Electrical Engineering, University of Zanjan, Zanjan, Iran, where he is currently working as an Associate Professor. His research interests include modeling, simulation, and fault diagnosis of electrical machines and drives as well as the power system protection.

Asghar Taheri

Asghar Taheri received the B.S., M.S., and Ph.D. degrees, all in electronics engineering, from the Amirkabir University of Technology and the Iran University of Science and Technology, Tehran, Iran, in 1999, 2001, and 2011, respectively. He has been a Member of Faculty at the University of Zanjan, Iran, since 2010, where he was an Assistant Professor from 2011 to 2016 and has been an Associate Professor since 2016. His current research interests include: modeling, analysis, and control of power converters, motor drives, and multi-phase machine drives, multi-level inverter, power electronic systems for renewable energy sources, process control, DSP and FPGA based system designs, hardware in the loop, and computer-aided control.