DC generators can be classified according to their methods of field excitation. There are two types of DC generators on the basis of excitation. Separately excited DC generators Self excited DC generators Separately excited DC generators If the field winding is excited by a separate DC supply, then the generator is called separately DC generator.
Types of DC Generators – Pedagogy Zone Read More »
DC Generator : An electrical generator is a rotating machine which converts mechanical energy into electrical energy. It is shown in figure. This energy conversion is based on the principle of electromagnetic induction. According to Faraday’s laws of electromagnetic induction, whenever a conductor is moved in a magnetic field, dynamically induced e.m.f is produced in
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Like a four wheel vehicle, a two wheel vehicle will also be subjected to gyroscopic and centrifugal couple when it takes a turn on a curved path. Let us consider a two wheel vehicle, (say, a scooter or a motor bicycle) taking a right turn, as shown in fig. Let, m = Mass of the
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Consider any four wheel automobile (say, car) having wheels A, B, C and D, taking a turn towards left on a curved path, as shown in Fig (a). The wheels A and C are inner wheels, whereas B and D are outer wheels. While the vehicle will move in a straight line there will not
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Before discussing the gyroscopic effect on naval ships, first let us brief the terminology used in connection with the naval ship. Ship Terminology The front, top, and side views of a naval ship are shown in fig (a), (b) and (c) respectively. The terms used are: Bow: It is the fore or front end of
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We already know that the angular acceleration is the rate of change of angular velocity. It is a vector quantity and can be represented both in magnitude and direction with the help of right hand screw rule. A body rotating in a plane about a fixed axis is subjected to the angular acceleration. But whenever
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The spring controlled governor of the Wilson Hartnell type is shown in Fig. In this governor, the bell crank levers are pivoted at the ends of two arms which rotate with the spindle. The vertical arms of the bell crank lever support the balls and horizontal arms are attached to the sleeve through rollers. The
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Figure shows a simplified overview of the database design process. The first step shown is requirements collection and analysis. During this step, the database designers interview prospective database users to understand and document their data requirements. The result of this step is a concisely written set of users’ requirements. These requirements should be specified in
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In this section, we give an overview of the schema evolution commands available in SQL, which can be used to alter a schema by adding or dropping tables, attributes, constraints, and other schema elements. This can be done while the database is operational and does not require recompilation of the database schema. Certain checks must
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Governor Arrangement This is the most common type of governor. In the centrifugal type governors, rotation of the crank shaft is taken to a vertical spindle through suitable gears. It consists of two balls of equal mass, which are attached to the arms as shown in Fig. These balls are known as governor balls or
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