What will happen to the operation of Transformer if the frequency of operation is changed?

Change in frequency affects the operation of a transformer in the following ways: i. Iron Loss – Increases with a decrease in frequency. A 60 Hz transformer will have nearly 11% higher losses, when worked on 50 Hz instead of 60 Hz. However, when a 25 Hz transformer is worked on 60Hz, iron losses are reduced by 25%. ii. Cu Loss – In distribution transformer, it is independent of frequency. iii. Efficiency- Since Cu loss is unaffected by change in frequency, a given transformer efficiency is less at a low frequency than at a higher one. iv. Regulation...

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DC Machines

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Discus the types and works of power plants used in ships, Airplanes, industries and commercial enterprises

Power Plants used in Industries:  Power plants used in industries are known as captive power plants these are used only for industry demand. Type of power plant installed in industries depends upon the fuel feasibility for industry. Most of the industries use gas and diesel power plants. However nowadays industries are prone towards renewable sources of energy i.e. Solar and wind.    Power Plants used in Airplanes: Engine driven generators are used in airplane due to accessibility of air. Both AC and DC generators are used...

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What are direct energy conversion methods for producing electric power?

: There are seven fundamental methods of directly transforming other forms of energy into electrical energy: §  Static electricity, from the physical separation and transport of charge (examples: triboelectric effect and lightning) §  Electromagnetic Induction, where an  electrical generator, dynamo or alternator transforms             generator kinetic energy (energy of motion) into electricity. This is the most used form for generating electricity...

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List out all energy worldwide available natural energy resources for electrical power generation.

Ans.      Energy resources are categorized in two groups conventional and non conventional. Available      resources worldwide for electrical power generation  are enlisted below:     Conventional Sources: ü  Coal Energy. ü  Hydel Energy. ü  Diesel Energy. ü  Gas Energy.   Non-Conventional Sources: ü  Solar Energy. ü  Wind Energy. ü  Biomass Energy. ü  Ocean Energy. ü  Nuclear Energy. ü  GeoThermal Energy. Some ...

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What is Turbine's Critical Frequency and why a turbine should not be operated at its critical frequency?

Answer: Turbine shaft material has its own natural frequency, when turbine rotates on such a speed that frequency of shaft become close to its natural frequency, machine causes noise & high vibrations because of resonance due to matching of frequency. Running of Steam "TURBINE" on this speed is avoided & this is called Critical speed. A turbine may have more then one critical speed, which may depend upon number of couplings.  A second critical speed is when the Turbine blade tips approach the speed of sound. This effectively limits...

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Why efficiency in Thermal Power Plant is Low?

Almost 50% of the heat generated is lost at the condenser as heat rejection. It is unavoidable as with out heat rejection it is not possible to convert heat energy into mechanical energy and drive the turbine without drop in temperature. Therefore majority of the loss takes place in the condenser. Thus efficiency of the thermal power plant is between 30-35%. On What Cycle does Thermal Power Plant operate? Thermal Power plant works on the principle of Rankine cycle Why Generation Voltage in Thermal Power Plant is between 11kV to 33kV? The current...

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Electronics Fundametals Chapter 8

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