Search for dissertations about: "rotors"

Showing result 1 - 5 of 36 swedish dissertations containing the word rotors.

2. 1. Analysis and Reduction of Parasitic Effects in Induction Motors With Die-Cast Rotors

   Author : Alexander Stening; Chandur Sadarangani; Nicola Bianchi; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aluminium rotors; asynchronous torques; copper rotors; die-cast rotors; induction machines; inter-bar currents; modulated rotors; starting torque; stray losses; synchronous torques;

   Abstract : This thesis presents a study of inter-bar current effects on induction motors with die-cast aluminium and die-cast copper rotors. The parasitic effects introduced by these currents are analyzed and possible solutions to these problems are presented. This is realized by developing analytical tools for the simulation of inter-bar current effects. READ MORE

4. 2. On Inter-bar Currents in Induction Motors with Cast Aluminium and Cast Copper Rotors

   Author : Alexander Stening; Chandur Sadarangani; Ola Aglén; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Induction motors; Inter-bar currents; Copper rotors; Aluminium rotors; Starting torque; Asynchronous torques; Starting current; Stray losses; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Abstract : This thesis presents a study of the effects of inter-bar currents on inductionmotor starting performance and stray-load losses. The work is focused on theperformance differences between aluminium and copper casted rotors.A method to predict the stator current when starting direct-on-line isdeveloped. READ MORE

5. 3. Dynamics of Rotors Influenced by Rubbing Contacts

   Author : John L. Isaksson; Göran Gerbert; Linköpings universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : This thesis concerns theoretical studies of the dynamical behaviour of a rotor interacting with its non-rotating surroundings. Rotor-stator rubs make the rotor system strongly non-linear, which leads to phenomena that are not seen for ordinary rotors. READ MORE

6. 4. Modelling and analysis of hydropower generator rotors

   Author : Rolf Gustavsson; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Datorstödd maskinkonstruktion; Computer Aided Design;

   Abstract : In almost all production of electricity the rotating machines serves as an important part of the energy transformation system. In hydropower units, a hydraulic turbine connected to a generator converts the potential energy stored in the water reservoir into electrical energy in the generator. READ MORE

7. 5. Simplified models to evaluate nonlinear dynamics in hydropower rotors

   Author : Florian Thiery; Yukio Ishida; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Computer Aided Design; Datorstödd maskinkonstruktion;

   Abstract : In hydropower systems, it is essential to avoid catastrophic failures that lead to human and economic losses. Unfortunately, a hydropower rotor can behave abnormally since several nonlinear effects occur during start-up, shut-downs or when running at nominal speed. READ MORE