Abstract
The Goerges phenomenon is the operation of a 3-phase wound-rotor induction motor at half of synchronous speed, and it is obtained by unbalancing the rotor circuit. If the motor is started with one rotor phase opened or with rotor impedances greatly unbalanced, it will accelerate to half speed and operate stably as a motor or generator. Several investigators have made tests and analyses to find the characteristics of a motor operated in this way. In the present work a physical explanation and an equivalent circuit are given. Results of tests and calculations for a 5-horsepower motor are compared and found to be in good agreement. The unbalanced rotor impedances cause unbalanced rotor currents of slip frequency, and balanced stator currents of two frequencies, the fundamental and a subharmonic, the frequency of which depends on the speed. The motor may be operated stably at half or full speed. The torque at half speed is greater than at full speed, and may be almost as great as the rated torque for a balanced rotor. It may be desirable to operate an induction motor at half speed intermittently or as a temporary measure. Disadvantages of half speed operation are the low power factor, low pull-out torque, the subfrequency line currents, and motor vibrations.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Transactions of the American Institute of Electrical Engineers
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
