A Method for Determining Nonlinear Inductances of Electrical Equivalent Circuit for Three-Phase Induction Motor

Abstract

Accurate values of the equivalent circuit parameters of three-phase induction motor are critical for its precise performance evaluation. Motor parameters, mainly the inductances obtained from conventional no-load and blocked rotor tests are constant parameters for all load conditions. However, due to inherent nature of the core material property, i.e., nonlinear B-H curve, the inductances do not remain constant in practical. This work proposes a method comprising simple tests using which all the motor nonlinear inductances can be determined. The motor mathematical model under the test conditions is also developed. The results obtained from equivalent circuit using the nonlinear inductances are validated with experimental results for two different motors and good agreement has been achieved. It is observed that the motor performances calculated using nonlinear inductances matches more closely to experimental results as compared to that using constant inductances.

Keywords::

• equivalent circuits
• inductance measurement
• induction motors
• mathematical model
• nonlinear circuits
• parameter estimation
• performance evaluation
• saturation magnetization
• tests

Additional information

Notes on contributors

Mohammed Nasir Ansari

Mohammed Nasir Ansari was born in Namchi, India in 1976. He received the B. Tech. degree in electrical engineering from R.E.C. Hamirpur (now N.I.T. Hamirpur), Hamirpur, H.P., India in 1998; M. Tech. degree in machines, drives and power electronics from I.I.T Kharagpur, Kharagpur, West Bengal, India in 2008. Since 2001, he has been working with the Department of Electrical and Electronics Engineering, Sikkim Manipal Institute of Technology and is presently posted as Associate Professor. He is also pursuing Ph.D. from Department of Electronics and Electrical Engineering,

I.I.T. Guwahati, Guwahati, Assam, India. His current research interests includes analysis of electrical motors and electric motor drives.

Ankit Dalal

Ankit Dalal was born in Burhanpur, India in 1988. He received the B. Tech. degree in electrical engineering from S.V.N.I.T. Surat, Gujrat, India in 2011. He received his Ph.D. degree in electrical engineering from I.I.T. Guwahati, Guwahati, Assam, India in 2017. Since 2016, he is working in Nonferrous Materials Technology Centre (NFTDC), a Research and Development Institute in Hyderabad, India. His main research interest includes Electrical machine design, Power electronics and Drives for electric vehicles.

Praveen Kumar

Praveen Kumar has core expertise of both Electrical Engineering Industry and Academics. Currently he is working as Associate Professor in the Department of Electronics and Electrical Engineering in Indian Institute of Technology Guwahati. His research activities are in optimization of electrical motors and drives; state of the art algorithm development for multi-objective optimization and simulation; and design of electrical motors and actuators using finite element methods; besides years long hands on experience with analytical modeling of electrical motors for rapid simulation.