What are losses of Transformer? Draw an equivalent circuit of Transformer.

Losses of TransformerThe power losses in a transformer are of two types, namely;1.         Core or Iron losses      2.         Copper losses These  losses  appear  in  the  form  of  heat  and  produce  (i)  an  increase  in temperature and (ii) a drop in efficienc...

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What is the difference between a transformer, a converter and a power supply?

Transformer A Transformer is an electrical device by which alternating current of one voltage is changed to another voltage using coils. There are several different types, but they all basically do the same thing - change the voltage. They are usually heavy for their size due to the weight of the coils (size and weight depends on their rating). Converter A Converter is an electronic device that is used in some cases instead of a transformer. The converter doesn’t actually lower the voltage, but rather delays each electrical cycle making...

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What is the difference between 3 phase and single-phase electricity?

I suppose the textbook definition would be something like this: A phase is the factional part of the period of a sinusoidal wave, usually expressed in electrical degrees. A single-phase circuit is an alternating-current using only one, sine wave type, current flow. A three-phase circuit consists of three different sine wave current flows, different in phase by 120 degrees from each other. Now let's have the more practical, "down to earth" definition - something that the average homeowner would at least have a chance of understanding: Single...

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Discuss basic principles of DC generator, AC generator (Alternator) & Motor.

DC Generator PrincipleAn electrical generator is a machine which converts mechanical energy (or power) into electrical energy (or power)....

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Draw half & full wave rectifier showing input and output signals.

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Sketch a flow chart of power generation system in a Gas fuel based power plant.

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Define power factor. What are ways to improve power factor & describe them with necessary diagrams.

Definition of Power Factor: The cosine of the angle between voltage and current in an AC circuit is known as power factor. Or The power factor of a circuit can be defined in one of the following three ways: Power factor = cos ∅ = cosine of the angle between V and I Power factor = R/Z=Resistance/Impedance Power factor = (VIcos ∅)/VI=(Active Power)/(Apperant Power) Ways to Improve Power Factor: Power Factor is a number between...

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10 Interview Questions and Answers on Transformers - Part-1

Figure: Power transformer over-excitation condition caused by decreased frequency; flux (green), iron core's magnetic characteristics (red) and magnetizing current (blue). 1. How is magnetic leakage reduced to a minimum in commercial transformers? By interleaving the primary and secondary windings. 2. Mention the factors on which hysteresis loss depends? (i) Quality and amount of iron in the core (ii) Flux density and (iii)...

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Why Transformer Rating in KVA instead of KW ?

As seen, Cu loss of a transformer depends on current and iron loss on voltage. Hence, total transformer loss depends on volt-ampere (VA) and not on phase angle between voltage and current i.e. it is independent of load power factor. That is why rating of transformers is in kVA and not in kW. Another Answer: There are 2 losses in transformer. One is copper loss which depends on current and the other is iron loss which depends on voltage. These two factors are not affected by the power factor. This is why transformers are rated in KVA and not...

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What do you mean by mechanical & electrical frequency? Derive equations for them & show that they are co-related.

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What do you mean by real, reactive & apparent power?

a)      Real Power (P)It is the power which is actually dissipated in the circuit resistance. Also called Active Power. Measured in Units of Watts b)     Reactive Power (Q)It is the power developed in the inductive reactance of the circu...

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