Abstract—The study of induction machine is becoming important in power system dynamic analysis. An accurate algorithm for determining induction machine transients is presented here. Higher order model of double cage induction machine is simplified and solved using Runge-Kutta, Trapezoidal and Euler’s methods in Mat-lab platform. The authors compute the rotor speed versus time profile, stator current and stator flux linkage for various load conditions and supply voltage disturbances using the concept of the speed-build up of induction machines. The 7th order model of a double cage induction machine has been reduced here to a 5th order model with a structure different from the regular 5th order model for single cage induction machine. Model Order Reduction (MOR) incorporates a set of techniques aiming at generating reduced order models with lower complexity while ensuring the I/O response and other characteristics of the original model (such as passivity). To obtain stability in digital simulation, winding flux-linkages are used as state variables in contrast to current flow. Comparison of computational times in the reported three methods is made. We have verified less computation time in reduced order models and an improvement in the accuracy is also observed.

Index Terms—Induction machine, Order reduction, Stability, Transient analysis, Power System.

Sudhir Kumar and P. K. Ghosh are with Faculty of Engineering and Technology, Mody Institute of Technology and Science (Deemed University), Lakshmangarh-332 311, Distt. Sikar, (Rajasthan), India. (Fax:+91-1573-225042;email:skumar_icfai@yahoo.co.in;pkghosh_ece@yahoo.co.in).
S. Mukherjee is with the Department of Electrical Engineering, Indian Institute of Technology Roorkee, Uttrakhand, India.(email:mukherjee.shaktidev@gmail.com).

Cite: Sudhir Kumar, P. K. Ghosh and S. Mukherjee, "The d-q Modeling, Order Reduction and Numerical Analysis of Double Cage Three Phase Induction Machine for Power System Studies," International Journal of Computer and Electrical Engineering vol. 3, no. 2, pp. 303-308, 2011.