Parallel Operation of a Synchronous Generator with a Power System A synchronous generator can be brought in for parallel operation with a power system in anyone of two method, exact synchronizing and self-synchronizing. We will consider exact synchronizing. In this case (Fig 13), the instantaneous emf of a generator phase, say, eA1, must be equal […]
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Electricity and Magnetism
Control of the Active and Reactive Power of a Synchronous Generator
Control of the Active and Reactive Power of a Synchronous Generator The active power P = 3VIact of a synchronous generator operating into a large power system (V = const) can be controlled by adjusting the power delivered by its prime mover Pm = ɷrotTPm An increase in the power (or, which is the same, […]
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The V-Curve of a Synchronous Generator
The V-Curve of a Synchronous Generator A valuable property of a synchronous generator operating into a large power system is that its reactive current can be controlled by varying its excitation current. For a better understanding of the matter, let us turn to the phase phasor diagram of a synchronous generator (see Fig 8) and […]
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The Electromagnetic Torque and the Load-Angle Characteristic of a Synchronous Generator
The Electromagnetic Torque and the Load-Angle Characteristic of a Synchronous Generator Le t us see how the power P and the electromagnetic torque Tem of a synchronous generator depend on the load angle θ (θ < 0) . To this encl, we will refer to the phasor diagram in Fig 8. The electric power supplied […]
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Operation of a Synchronous Generator in a Large Power System
Operation of a Synchronous Generator in a Large Power System A large three-phase power system combines a great number of sources and of three-phase loads operating in parallel. It may be taken that a minor change in the number of sources and loads will not affect the operation of a large power system. Therefore, the […]
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The Power Rating and Efficiency of a Synchronous Generator
The Power Rating and Efficiency of a Synchronous Generator The power balance around a synchronous generator may be explained by reference to its phasor diagram (see Fig 4 b). By projecting the Ė0 phasor and its components onto the current phasor İ , we obtain the active component of the emf E0 cos φ0 = […]
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The Equivalent Circuit and a Simplified Phasor Diagram for a Phase of a Synchronous Generator
The Equivalent Circuit and a Simplified Phasor Diagram for a Phase of a Synchronous Generator The equivalent circuit answering the equation of electric slate of a stator phase of a synchronous generator is shown in Fig 4 a. Now we will construct a phasor diagram for a phase of a synchronous generator. To do this, […]
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The Equation of Electric State for a Phase of a Synchronous Generator
The Equation of Electric State for a Phase of a Synchronous Generator The magnetic field of a loaded synchronous machine is excited not only by the excitation current in the rotor winding, but also by the currents in the phase windings of the stator (armature). This implies that, similarly to d.c. machines, synchronous machine experiences […]
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Production of a Sinusoidal EMF in a Synchronous Generator
Production of a Sinusoidal EMF in a Synchronous Generator The stator winding of a synchronous machine is constructed in the same fashion as that of an induction machine. However, in an induction machine the emfs in the stator phase windings are induced by a rotating magnetic field. In a synchronous machine the emfs in the […]
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Motoring and Generating Action of a Synchronous Machine
Motoring and Generating Action of a Synchronous Machine Like other electrical machines, synchronous machines may be operated either as generators or as motors. Which action of, the two does take place depends on the interaction between the magnetic fields set up by the currents in the stator and rotor windings. Consider the operation of a […]
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