HIGH GRADE ENERGY Electrical and chemical energy are high-grade energy, because the energy is concentrated in a small space. Even a small amount of electrical and chemical energy can do a great amount of work. The molecules or particles that store these forms of energy are highly ordered and compact and thus considered as high […]
Energy can be stored in many forms. Chemical potential energy is stored in fuels such as coal, wood, and food, or in the chemicals in batteries and fuel cells. Phosphorescent materials store some of the energy they absorb from visible light. After a time delay, they convert this energy back into visible light. Often energy
Often the form of energy most readily available is not the most useful form. Coal can be burned to provide heat, but converting the chemical energy stored in coal into electrical energy requires a series of intermediate steps. In each step of the conversion process, some energy is wasted. ELECTRICAL ENERGY TO MECHANICAL ENERGY OF
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Although there are many ways to classify energy, we will discuss eleven forms of energy. The first three forms of energy are related to the energy of motion associated with moving objects, atoms, and molecules. MECHANICAL ENERGY OF MOTION: Moving objects exhibit mechanical energy of motion, also called kinetic energy. A ball thrown through the
In a HV test field, the HV components of test systems are designed with an external indoor insulation usually. When internal insulation shall be tested, the test voltage must be connected to the internal part of the apparatus to be tested. This is usually done by bushings which have an external insulation. For reasons of
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From a practical standpoint, we define the optimization task as follows: given a system or process, find the best solution to this process within constraints. This task requires the following elements: • An OBJECTIVE FUNCTION is needed that provides a scalar quantitative performance measure that needs to be minimized or maximized. This can be the
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For voltages higher than about 300 to 500 kV, the cascading of transformers is a big advantage, as the weight of a whole testing set can be subdivided into single units and therefore transport and erection becomes easier. Also, with this, the transformer cost for a given voltage may be reduced, since cascaded units need
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For voltages higher than 400 KV, it is desired to cascade two or more transformers depending upon the voltage requirements. With this, the weight of the whole unit is subdivided into single units and, therefore, transport and erection becomes easier. Also, with this, the transformer cost for a given voltage may be reduced, since cascaded
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Voltage sags may cause lamps to extinguish. Light bulbs will just twinkle; that will likely not be considered to be a serious effect. High pressure lamps may extinguish; it takes several minutes for them to re-ignite. All lamps, except incandescent lamps, require high voltage across the lamp electrodes during starting. This voltage is essential to
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A rotating machine is less exposed to lightning surge as compared to transformers. Because of the limited space available, the insulation on the windings of rotating machines is kept to a minimum. The main difference between the winding of rotating machine and transformer is that in case of rotating machines the turns are fewer but
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