Investigation of the effects of the equivalent circuit parameters on induction motor torque using three different equivalent circuit models

Abstract

In this study, the most vital characteristic properties of induction motor, motor starting, maximum and nominal torque are analyzed for what are affected. For the analysis of torque, L type, T type and IEEE 112 equivalent circuit model is employed. Torque change is investigated with the help of codes developed in MATLAB to be used in electrical machines course. First, the slip-moment characteristic curve of the induction motor is divided into three working zones and it was determined which equivalent circuit model gave the best results in these study zones. Later, such parameters as stator and rotor resistance, stator and rotor reactance, magnetization reactance, core resistance and slip are researched for how torque values are affected from. The obtained values for each of the three equivalent circuit models are given and compared with experimental results. 50 HP squirrel cage induction motor parameters are used in analysis. In the analysis, the most influential parameters on the starting torque are found as rotor resistance and stator and rotor reactance. Change of other parameters’ impact ratio depending upon right proportion and inverse proportion is observed. When nominal torque variations are investigated, again rotor resistance is the most influential parameter and by selecting proper factor effecting rotor resistance during design, the result of acquiring desired rotor resistance is obtained. When the maximum torque variations are examined, it appears that the stator and rotor reactance values are effective. Starting, maximum and nominal torque expressions change with square of voltage alters the effect on them a lot. Therefore, triangle or star connection importance arises during machine design.

Analytical transformations software for stationary modes of induction motors and electric drives

“…The proposed equivalent circuit of the IM with the skew effect, stray load loss, iron core loss, and mechanical losses [6] Figure 12. The induction machine RML-EC [7] Figures [13][14][15][16][17][18][19] show the curves ω=f(T), which show the experimentally obtained curves ω=f(T) in stationary mode. They illustrate the curves ω=f(T) for various asynchronous motors.…”

“…However, the cited papers did not discuss, set and solve the problem of calculating the whole family of characteristics for different IMs, as it was done in our paper. Thus, the papers [2]- [7], [8]- [13], [14]- [20] only show the existence and reality of the problem of obtaining an extensive family of IM characteristics, based on the variety of their equivalent circuits.…”

Derived Functions for MATLAB Non-linear Solvers – an optimal Stator Slot Design Stopgap

“…In order to eliminate the few drawbacks of the SCIM, the designer should make a preliminary modeling and determine the physical size via parametric optimization with modern software in accordance with the requirements of the application [4]. The induction motor design is considered a nonlinear programming problem, where one or more objective cost functions of the design are minimized.…”

The influence of non-sinusoidal voltage sources on the steady state performance of different NEMA Designs of IMs

“…The most important loads used in the electric power system are electric motors, which in industrial applications consume about 40% of all the generated electrical energy worldwide (Ruthes et al, 2016). Among them, squirrel cage induction motors (SCIMs) are extensively used in a variety of industrial applications such as centrifugal pumps, industrial drives, large blowers and fans, machine tools, lathes, , and other turning equipment due to their characteristics such as simple and robust structure, low cost, wide speed adjustment, minimal maintenance need, wide power range, reliable operation, and mass production technology (Tezcan et al, 2018).…”