Shunt generators are ideally suited for stable parallel operation owing to their______________?
Show answer Hide answer
Answer: C. drooping voltage characteristics
Explanation
Shunt generators feature terminal voltages that decrease automatically as output load current increases significantly. This natural drooping voltage characteristic prevents any single machine from hogging an excessive share of the total load. Consequently, parallel shunt generators share electrical loads stably without requiring complex active balancing control systems. Parallel operation of DC generators requires compatible voltage regulation curves to ensure safe and balanced load sharing. Armature resistance and armature reaction both contribute to the characteristic drooping voltage profile of shunt machines. If one generator takes more load, its output voltage drops, forcing it to shed load back to the parallel units.
Option A is incorrect because rising voltage characteristics cause instability and lead to uncontrolled load hogging in parallel. Option B is wrong since identical characteristics alone do not provide the stabilizing droop needed for automatic load sharing. Option D is incorrect because linear voltage profiles without droop fail to provide the necessary stability for parallel networks.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
Related questions
Q1. What occurs within a commutator_____________?
Show answer Hide answer
Answer: C. mica is harder than copper
Mica is an extremely hard mineral insulator placed between the conductive copper segments of a DC machine commutator. During operation, copper segments wear down faster than the surrounding mica due to friction from carb...
Q2. What is the status of an open-circuited armature coil in a DC machine________________?
Show answer Hide answer
Answer: C. both A. and (b)
Open circuits interrupt current flow through specific armature coils during rotation. Interruption causes severe sparking as the commutator segment passes brushes. Arcing burns and scars the specific commutator segments...
Q3. What conditions are necessary for satisfactory commutation in DC machines______________?
Show answer Hide answer
Answer: D. all of the above
Satisfactory commutation requires high-grade carbon brushes properly sized to match the current density requirements. Brushes must slide freely yet smoothly within their respective holders without binding or excessive vi...
Q4. What material is typically used to fabricate the armature core of a DC generator__________________?
Show answer Hide answer
Answer: A. silicon steel
Silicon steel possesses high magnetic permeability and exceptionally low core loss characteristics under alternating magnetic fields. These electrical properties make it the ideal material for fabricating efficient armat...
Q5. How are commutator segments linked to the armature conductors___________?
Show answer Hide answer
Answer: A. copper lugs
Copper lugs provide mechanical strength and reliable electrical connections. Armature coil ends are inserted securely into these terminal riser slots. Brazing or soldering ensures permanent low-resistance joints at the c...
Q6. What is the inverse of permeance______________?
Show answer Hide answer
Answer: B. reluctance
Reluctance measures the opposition offered by a magnetic circuit to the establishment of magnetic flux lines. Permeance represents the ease with which magnetic flux can be established within a given magnetic material pat...