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close this bookElectrical Machines - Basic vocational knowledge (Institut für Berufliche Entwicklung, 144 p.)
View the document(introduction...)
View the documentIntroduction
close this folder1. General information about electrical machines
View the document1.1. Definition of terms
View the document1.2. Types of electrical machines
View the document1.3. Operations of electrical machines
View the document1.4. System of rotating electrical machines (generators, motors, converters)
View the document1.5. System of stationary electrical machines (transformers)
close this folder2. Basic principles
close this folder2.1. The magnetic field
View the document2.1.1. Definition and presentation of the magnetic field
View the document2.1.2. Magnets Magnetic field
View the document2.1.3. Magnetic field of a current-carrying conductor
View the document2.1.4. Magnetic field of a current-carrying coil
View the document2.1.5. Magnetic fields in electrical machines
close this folder2.2. Measurable variables of the magnetic field
View the document2.2.1. Magnetomotive force
View the document2.2.2. Magnetic flow
View the document2.2.3. Magnetic flow density
close this folder2.3. Force action of the magnetic field
View the document2.3.1. Force action on cur rent-carrying conductors
View the document2.3.2. Force action on current-carrying coils (motor principle)
close this folder2.4. Voltage generation through induction
View the document2.4.1. General law of induction
View the document2.4.2. Stationary induction (transformer principle)
View the document2.4.3. Motional induction (generator principle)
close this folder3. Execution of rotating electrical machines
View the document3.1. Size
close this folder3.2. Designs
View the document3.2.1. Definition
View the document3.2.2. Designation
close this folder3.3. Degree of protection
View the document3.3.1. Definition
View the document3.3.2. Designation
close this folder3.4. Cooling
View the document3.4.1. Cooling category
View the document3.4.2. Cooling category designation
close this folder3.5. Mode of operation
View the document3.5.1. Definition
View the document3.5.2. Operational mode designation
View the document3.5.3. Frequent nominal cycle ratings
View the document3.6. Heat resistance categories
close this folder3.7. Connection designations of electrical machines
View the document3.7.1. Transformers
View the document3.7.2. Rotating electrical machines
close this folder3.8. Rotating electrical machines in rotational sense
View the document3.8.1. Clockwise rotation stipulation
View the document3.8.2. Direct current machines
View the document3.8.3. Alternating current and three-phase machines
View the document3.9. Rating plate
close this folder4. Synchronous machines
close this folder4.1. Operating principles
View the document4.1.1. Synchronous generator
View the document4.1.2. Synchronous motor
close this folder4.2. Constructional assembly
View the document4.2.1. Stator
View the document4.2.2. Rotor
close this folder4.3. Operational behaviour
View the document4.3.1. Synchronous generator
View the document4.3.2. Synchronous motor
close this folder4.4. Use of synchronous machines
View the document4.4.1. Synchronous generators
View the document4.4.2. Synchronous motors
close this folder5. Asynchronous motors
View the document5.1. Constructional assembly
close this folder5.2. Operating principles
View the document5.2.1. Torque generation
View the document5.2.2. Asynchronous principle
View the document5.2.3. Slip
close this folder5.3. Operational behaviour
View the document5.3.1. Start
View the document5.3.2. Rating
View the document5.3.3. Speed control
View the document5.3.4. Rotational sense alteration
close this folder5.4. Circuit engineering
View the document5.4.1. Starting connections
View the document5.4.2. Dahlander pole-changing circuit (speed control)
View the document5.4.3. Rotational reversing circuit
View the document5.4.4. Braking circuits
View the document5.5. Application
View the document5.6. Characteristic values of squirrel cage motors
close this folder6. Direct current machines
View the document6.1. Constructional assembly
close this folder6.2. Operating principles
View the document6.2.1. Power generation (direct current motor)
View the document6.2.2. Torque generation (direct current motor)
View the document6.2.3. Armature reaction (rotor reaction)
View the document6.2.4. Excitation
View the document6.2.5. Value relations
close this folder6.3. Operational behaviour of direct current machines
View the document6.3.1. Direct current generators
View the document6.3.2. Direct current motors
close this folder6.4. Circuit engineering and operational features of customary direct current generators
View the document6.4.1. Separate-excited direct current generator
View the document6.4.2. Direct current shunt generator
close this folder6.5. Circuit engineering and operational features of customary direct current motors
View the document6.5.1. Direct current motor with permanent excitation
View the document6.5.2. Direct current series motor
View the document6.5.3. Direct current shunt motor
close this folder7. Single-phase alternating current motors
View the document(introduction...)
close this folder7.1. Single-phase asynchronous motors (single-phase induction motors)
View the document(introduction...)
View the document7.1.1. Assembly and operating principle
View the document7.1.2. Operational behaviour
View the document7.1.3. Technical data
close this folder7.2. Three-phase asynchronous motor in single-phase operation (capacitor motor)
View the document7.2.1. Assembly and operating principle
View the document7.2.2. Operational behaviour
View the document7.3. Split pole motors
close this folder7.4. Single-phase commutator motors (universal motors)
View the document7.4.1. Assembly
View the document7.4.2. Operating principles
View the document7.4.3. Operational behaviour
View the document7.4.4. Technical data
close this folder8. Transformer
close this folder8.1. Transformer principle
View the document8.1.1. Operating principle of a transformer
View the document8.1.2. Voltage transformation
View the document8.1.3. Current transformation
close this folder8.2. Operational behaviour of a transformer
View the document8.2.1. Idling behaviour Idling features
View the document8.2.2. Short-circuit behaviour
View the document8.2.3. Loaded voltage behaviour
View the document8.2.4. Efficiency
close this folder8.3. Three-phase transformer
View the document8.3.1. Three-phase transformation with single-phase transformers
View the document8.3.2. Three-phase transformers
View the document8.3.3. Vector groups
View the document8.3.4. Application of three-phase transformers in power supply
View the document8.3.5. Parallel operation of transformers
View the document8.3.6. Technical data of customary transformers

5.5. Application

The assembly of an asynchronous motor is much simpler, and therefor also less costly and easier to service, than other motors. This applies in particular to squirrel cage motors. Asynchronous motors are manufactured up to 1000 KW performance. Survey 15 features the characteristic values for asynchronous motors ranging from 0 12 to 4 KW. As speed control still poses some difficulties, asynchronous motors are utilised in the first instance for drives requiring a constant speed. These include, amongst others, compressors, pumps, ventilators, many machine tools and textile machines. Asynchronous motors with attached gears, so-called geared motors, are available for low-speed drives.

The slip ring motor finds application given complicated starting conditions. Slip ring execution makes possible a certain degree of speed control through the additional motor resistor or by means of an additional voltage in the rotor circuit. A slip ring motor also permits counter current braking and, consequently also employment as hoisting gear drives.