- •Memorize the words and word combinations and their equivalents.
- •Find the words and combinations of words in the text and translate the sentences containing them.
- •Read and translate the text.
- •Translate the word combinations from the text:
- •Point out the sentences in the text in which the word “to make” should be translated as “примушувати”.
- •Answer the questions.
- •Find the sentences in the text telling you about two problems facing the simple two pole dc motor. Text b Compensation for stator field distortion
- •Make sure that you know these words and word combinations.
- •Read and translate the text.
- •Answer the questions.
- •Text c Dynamo Design Variations
- •Read and memorise the words and word combinations.
- •Permanent magnet motor – двигун з постійним магнитом
- •Read and translate the text.
- •Answer the questions.
- •Listen to the words and word combinations from the text. Pay attention to their meaning.
- •Memorize the words and word combinations and their equivalents.
- •Read and translate the text.
- •Match the words and word combinations (a-e) to the sentences (1-5)
- •Answer the questions to the text
- •Say if the statement to the text is true or false
- •Translate the sentences paying attention to Indefinite Tenses in Active and Passive. Correct the mistakes in the sentences.
- •Text b Basic construction
- •Listen to the words and word combinations from the text. Pay attention to their meaning.
- •Memorize the words and word combinations and their equivalents
- •Read and translate the text
- •Match the words and word combinations (a-e) to the sentences (1-5)
- •Answer the questions to the text
- •Say if the statements to the text are true or false
- •Translate the sentences paying attention to Indefinite Tenses in Active and Passive. Correct the mistakes in the sentences.
- •Text c Principles of operation
- •Listen to the words and word combinations from the text. Pay attention to their meaning.
- •Find the words and combinations of words in the text and translate the sentences containing them.
- •Memorize the words and word combinations and their equivalents.
- •Read and translate the text
- •Match the words and word combinations (a-f) to the sentences (1-6)
- •Answer the questions to the text
- •Define the functions of Participle I and Participle II in the following sentences
- •Say, which of the sentences are in the Active and which are in the Passive Voice
- •Translate the sentences paying attention to the Sequence of Tenses
- •Translate the following Conditional sentences
- •Transformer Text a
- •Read and memorize words and word-combination
- •Make sure that you know these words and word combinations.
- •Read and translate the text.
- •Math the following English words with the Ukrainian ones.
- •Find English equivalents to the words:
- •Translate the word combinations from the text:
- •Answer the questions to the text.
- •Text b Operation at different frequencies
- •Read and memorize the words and word-combinations
- •Be sure that you know these words
- •Read and translate the text.
- •Text c Limitations
- •Make sure that you know these words and word combinations.
- •Read and translate the text.
- •Find the equivalents to the following.
- •Text d Construction
- •Read and memorise the words and word combinations
- •Read and translate the text. Cores
- •Find the equivalents to the folloving English words:
- •Point out English equivalents to the words:
- •Translate the word combinations.
- •Answer the questions.
- •Read the passage about steel cores. Retell it. Text e Windings
- •Listen to the words and word combinations from the text and memorize them.
- •Read and translate the text.
- •Match the English words and word combinations with the Ukrainian ones.
- •Insulation of windings
- •Text g Shielding
- •Supplement Speed control
- •Dc motor starters
- •Shielding
- •Autotransformers
- •Voltage transformers
- •Pulse transformers
- •3 Phase electrical power Transformer
- •3 Phase Transformer Delta and Wye Connections
- •Перелік скорочень
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Read and translate the text
The AC induction motor comprises 2 electromagnetic parts:
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stationary part called the stator;
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rotating part called the rotor, supported at each end on bearings.
The stator and the rotor are each made up of:
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an electric circuit, usually made of insulated copper or aluminum, to carry current;
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a magnetic circuit, usually made from laminated steel, to carry magnetic flux.
The stator. The stator is the outer stationary part of the motor, which consists of:
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the outer cylindrical frame of the motor, which is made either of welded sheet steel, cast iron or cast aluminum alloy. This may include feet or a flange for mounting;
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the magnetic path, which comprises a set of slotted steel laminations pressed into the cylindrical space inside the outer frame. The magnetic path is laminated to reduce eddy currents, lower losses and lower heating;
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a set of insulated electrical windings, which are placed inside the slots of the laminated magnetic path. The cross-sectional area of these windings must be large enough for the power rating of the motor. For a 3-phase motor, 3 sets of windings are required, one for each phase.
Stator and rotor laminations
The rotor. This is the rotating part of the motor. As with the stator above, the rotor consists of a set of slotted steel laminations pressed together in the form of a cylindrical magnetic path and the electrical circuit. The electrical circuit of the rotor can be either:
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wound rotor type, which comprises 3 sets of insulated windings with connections brought out to 3 sliprings mounted on the shaft. The external connections to the rotating part are made via brushes onto the sliprings. Consequently, this type of motor is often referred to as a slipring motor;
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squirrel cage rotor type, which comprises a set of copper or aluminum bars installed into the slots, which are connected to an end-ring at each end of the rotor. The construction of these rotor windings resembles a ‘squirrel cage’. Aluminum rotor bars are usually die-cast into the rotor slots, which results in a very rugged construction. Even though the aluminum rotor bars are in direct contact with the steel laminations, practically all the rotor current flows through the aluminum bars and not in the laminations.
The other parts. The other parts, which are required to complete the induction motor are:
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two end-flanges to support the two bearings, one at the drive-end (DE) and the other at the non drive-end (NDE);
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two bearings to support the rotating shaft, at DE and NDE;
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steel shaft for transmitting the torque to the load;
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cooling fan located at the NDE to provide forced cooling for the stator and rotor;
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terminal box on top or either side to receive the external electrical connections.
Assembly details of a typical AC induction motor