Advanced Modeling of Electro Motor load

ByKabenla Armah

Supervisor: Jerome JouffroyCo-supervisor: Søren Top

Content

Introduction Modeling method Results Conclusion

Introduction

Main objective

Current Approach

To develop advanced models of electro motor capable ofemulating an arbitrary electro motor and under load conditions.

Using actual motors attached to a load for testing

Introduction

Problems• High

operational cost

• Testing time• Large testing

space• Varying setup

and configurations

Solution

Electric load

Electric motor models

Emulator

Introduction

Three-phase induction motor:

OperationMost popular AC motor for applications in industrial environment

Its operation is based on Faraday’s law of Induction, lenz law and lorentz force

Introduction

Three- phase induction motor

[8] Wikipedia ,http://en.wikipedia.org/wiki/Squirrel-cage rotor

Introduction

A recap of existing literature tells us [1]-[9]

8 equations needed Reduced number of equations using(DQO

transformation matrix) Balanced system

Problem Unbalanced systems

Modeling Method

Modeling Method Approach

Development of these equations using variation in energy Assumptions made: neglect hysterisis and core-loss,

uniform airgap length

Input power

Output power

losses

load

Electromagnetic power

Modeling Method

Stator side equation:

Modeling Method

Modeling Method

0

Modeling Method

Torque equation

Number of poles

Modeling Method

Speed Equation

Load torque

Coefficient of friction

Mechanical speed

Load torque

Results

Results

Simulation scenario Direct-online start(directly connected to

supply) Squirrel-cage induction motor( Vr=0) A load attached to the motor

Results

Case 1 Balanced system

Results

Three-phase Stator currents

Results

Torque Graph

Results

Speed Graph

Results Case 2

Voltage imbalance (single phase)

Results

Torque

Results

Three-phase Current graph

Results

Case 2 Inter-turn short-circuit (Stator Phase A )

Results

Torque Graph

Results

Three-phase current graph

Conclusion

This model Demonstrate the behaviour of the induction

motor under balanced conditions More flexibility in varying parameters to

demonstrate system imbalance

Thank you

References

[1] Dal Y. Ohm, ”Dynamic Model of Induction Motors For Vector Control”, Drivetech, Inc., Blacksburg, Virginia. [2] P.C.Sen,”Principles of Electric Machines and Power Electronics, 2nd Edition”: Wiley, 1996. [3] Erickson, Robert W., Maksimovic, Dragan,”Fundamentals of Power Electronics,2nd Edition”: Springer

2001. [4] A. M. Trzynadlowski, The Field Orientation Principle in Control of Induction Motors :Kluwer Academic

Publishers, 1994. [5] Benot Robyns, Bruno Francois, Philippe Degobert and Jean Paul Hautier,”Vector Control of Induction

Machines, Desensitisation and Optimisation Through Fuzzy Logic”:Springer, 2012. [6] R. J. Lee, P. Pillay and R. G. Harley,” D,Q Reference Frames for the Simulation of Induction Motors”,

Electric Power Systems Research, 8 pp. 15 -26, 1984/85. [7] Chee-Mun Ong,”Dynamic Simulation of Electric Machinery, Using Matlab/Simulink”:Prentice Hall, 1997. [8] Wikipedia ,”http://en.wikipedia.org/wiki/Squirrel-cage rotor” [9] Nidec Corporation,”http://www.nidec.com/en-NA/technology/motor/basic/00026/” [10] TMEIC, ”https://www.tmeic.com/Southeast%20Asia/732-Energy%20Savings%20Wound%20Rotor

%20Induction%20Motor%20Savings- 374” [11] Hsin-Jang Shieh and Kuo-Kai Shyu, ”Nonlinear Sliding-Mode Torque Control with Adaptive Backstepping

Approach for Induction Motor Drive”,IEEE Transactions on Industrial electronics: VOL.46, NO.2, APRIL 1999.

Electric_energy= winding_losses + electromagnetic_energy

Modeling Method

Subscript: s-stator, r-rotor

Modeling Method

Rotor three-phase Equation: