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What is the conventional method of exciting the field windings of synchronous generators?
What is the conventional method of exciting the field windings of synchronous generators?
The conventional method involves mechanically coupling three machines: a pilot exciter, main exciter, and main 3-phase alternator, with the pilot exciter feeding the field winding of the main exciter, and the main exciter's dc output being given to the main alternator's field winding.
What are the limitations of the conventional excitation method?
What are the limitations of the conventional excitation method?
The limitations include cooling and maintenance problems associated with slip rings, brushes, and commutators, especially as alternator ratings rise.
What is the purpose of the pilot exciter in the conventional excitation method?
What is the purpose of the pilot exciter in the conventional excitation method?
The pilot exciter is a dc shunt generator that feeds the field winding of the main exciter.
What is the main exciter in the conventional excitation method?
What is the main exciter in the conventional excitation method?
What is the trend in modern excitation systems?
What is the trend in modern excitation systems?
What is the principle of static excitation?
What is the principle of static excitation?
What type of excitation system is used in large turbogenerators due to its many advantages?
What type of excitation system is used in large turbogenerators due to its many advantages?
What is the purpose of using space and time phasor diagrams in synchronous machines?
What is the purpose of using space and time phasor diagrams in synchronous machines?
What is the effect of the orientation of the armature mmf wave with respect to the field poles in a synchronous machine?
What is the effect of the orientation of the armature mmf wave with respect to the field poles in a synchronous machine?
What is the significance of the fir'nB' in the alternator?
What is the significance of the fir'nB' in the alternator?
What is the advantage of the brushless excitation system in terms of direct current?
What is the advantage of the brushless excitation system in terms of direct current?
What is the main difference between a brushless excitation system and a traditional brush-gear design?
What is the main difference between a brushless excitation system and a traditional brush-gear design?
What is the approximate time-phase angle between Ia and Vt in Fig. 5.35 (b)?
What is the approximate time-phase angle between Ia and Vt in Fig. 5.35 (b)?
What is the effect of synchronous machine losses on the operating point A in Fig. 5.17 (6)?
What is the effect of synchronous machine losses on the operating point A in Fig. 5.17 (6)?
How can the leakage reactance XL be obtained from the diagram in Fig. 5.17 (6)?
How can the leakage reactance XL be obtained from the diagram in Fig. 5.17 (6)?
What is the assumption made about the alternator in order to obtain its external load characteristics?
What is the assumption made about the alternator in order to obtain its external load characteristics?
What is the relationship between Ef and Vt at no load, according to Fig. 5.36 (a)?
What is the relationship between Ef and Vt at no load, according to Fig. 5.36 (a)?
What happens to Vt relative to Ef when the load is lagging, according to Fig. 5.36 (b)?
What happens to Vt relative to Ef when the load is lagging, according to Fig. 5.36 (b)?
What is the voltage induced in the armature winding due to the q-axis armature reaction component Faqt?
What is the voltage induced in the armature winding due to the q-axis armature reaction component Faqt?
What are Xad and Xaq in a salient pole synchronous machine?
What are Xad and Xaq in a salient pole synchronous machine?
What is the relationship between Fr, Ef, Ead, and Eaq in a salient pole synchronous machine?
What is the relationship between Fr, Ef, Ead, and Eaq in a salient pole synchronous machine?
How can the armature leakage reactance drop be resolved?
How can the armature leakage reactance drop be resolved?
What is the voltage equation for each phase of a salient-pole synchronous generator?
What is the voltage equation for each phase of a salient-pole synchronous generator?
What is the purpose of the phasor diagram in the analysis of salient-pole synchronous generators?
What is the purpose of the phasor diagram in the analysis of salient-pole synchronous generators?
What is the sign of the active power P for a synchronous generator and a synchronous motor?
What is the sign of the active power P for a synchronous generator and a synchronous motor?
What is the value of reactive power Qog when the load angle δ is 0°, according to Eq.(5.45)?
What is the value of reactive power Qog when the load angle δ is 0°, according to Eq.(5.45)?
What happens to the alternator when the reactive power Qog is negative, according to Eq.(5.45)?
What happens to the alternator when the reactive power Qog is negative, according to Eq.(5.45)?
What is the value of reactive power Qim when the load angle δ is 0°, according to Eq.(5.46)?
What is the value of reactive power Qim when the load angle δ is 0°, according to Eq.(5.46)?
Why is the reactive power Qim plotted above the reference line in Fig. 5.43 when the motor is delivering reactive power?
Why is the reactive power Qim plotted above the reference line in Fig. 5.43 when the motor is delivering reactive power?
What happens to the alternator when the load angle δ is 60°, according to Eq.(5.45)?
What happens to the alternator when the load angle δ is 60°, according to Eq.(5.45)?
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