Sidra Inam
University of Engineering & Technology
12/10/2012
2012
Sidra Inam
University of Engineering & Technology
12/10/2012
Why Starting Current of Induction Motor Is Higher Than the Synchronous Motor
Why Starting Current of Induction Motor Is Higher Than the Synchronous Motor
Starting Current Of Induction And Synchronous Motors:-
Starting Current of both motors were different, when analyzed using ETAP. Starting current of Induction motor was more than that of the synchronous motor. However Induction motor is used for Stable operation in running condition [1]
Reason:-
Before Complete description following parameters should be known * Current in rotor in case of Induction motor is “AC” and in case of synchronous it is “DC”[2] * Magnetization in case of Induction motor is induced while in Synchronous it is fed by external source[2] * Torque of Induction Motor is lower than synchronous motor[2] * An induction machine is an asynchronous machine that has a magnetic circuit interlinked with two electric circuits, or sets of circuits, rotating with respect to each other.[3] * Power is transferred from one circuit to another by electromagnetic induction.[3]
Induction Motor:- Many problems are a result of high or low voltage, unbalanced voltage, ungrounded power systems, or voltage spikes. When specifying the motor, it is important to understand what the true voltage at the motor terminals is during starting. This is not the power system voltage, or the tap on the autotransformer. To determine this voltage, one must take into account the total line drop to the motor terminals during the high current draw, which is present while the motor is starting.
There is a common misconception that high locked rotor torque (LRT) will ensure successful starting of the motor and its driven equipment. In the majority of applications, successful starting has little to do with the LRT. In fact, requiring a high LRT and
References: - [1] www.abb.com/motors&generators [2] Technical note Induction versus synchronous: how to select the right type of motor [3] http://www.pdhengineer.com/pages/E‐1005.htm [4] Troubleshooting Induction Motors by William R. Finley (Senior Member) Large Motors & Pumps Siemens Energy & Automation [5] Course № E-1005 Induction and Synchronous Motor Fundamentals [6] Synchronous motors by Dr. Suad Ibrahim Shahl [7] weg report on synchronous motor