When a flywheel is used with a DC compound motor to minimize peak demand, what configuration must the compound motor have_____________?
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Answer: C. cumulatively compounded
Explanation
A cumulatively compounded motor works effectively with a flywheel to smooth out severe peak demands. When load spikes, the motor slows down slightly, allowing the flywheel to release stored kinetic energy. This cooperative action protects the electrical supply system from sudden and damaging current surges. Flywheels store rotational kinetic energy and release it when driven equipment encounters sudden resistance. Cumulative compounding assists this process by allowing natural speed drooping under heavy loads. Differential compounding weakens flux under load, which causes unstable speed characteristics and stalling.
Heavy industrial machinery like metal stamping presses utilize flywheels for peak load management. Properly configured motor-flywheel systems reduce peak electricity consumption and lower operating costs. Engineering these setups prevents thermal overloads in factory distribution transformers. Level compounded motors maintain constant speed and prevent the flywheel from releasing its stored energy. Under compounded motors provide insufficient speed droop to let the flywheel assist the load effectively. Differentially compounded motors are unstable and completely unsuited for heavy peak load applications.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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