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单选题
The power factor of an AC generator operating singularly is determined by the （）
A
connected load
B
prime mover speed
C
field excitation
D
generators rated voltage
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A laptop operates on battery power when connected with an AC adapter. Once the battery discharges, the computer turns off and will not turn back on. Which of the following are the MOST likely causes of the laptop issue? （）(Select TWO).A、The LCD monitor’s power inverter does not function properly.B、The operating system’s power settings prevent the battery from charging.C、The battery is not compatible with the laptop.D、The internal power connection on the motherboard is faulty.E、The power adapter is not working.
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单选题The purpose of DC generator brushes is to （）.A
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conduct electric current to an outside circuitC
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单选题A DC generator is used to supply direct current in order to maintain an AC generator field and is known as a/an （）A
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voltage regulatorsB
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prime mover governors
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connected loadB
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field excitationD
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decrease the field excitationC
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increase the speed of the prime mover
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a variable-speed AC generatorB
a fixed-speed AC generatorC
an air blowerD
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connect to the busbar when the load increasingB
supply power specially to charging panelC
be put into operation during the ship arriving at or leaving portD
ensure the power supply to critical equipment after the main switchboard out of power
考题
单选题Why is it desirable to operate paralleled AC generators at the same power factor?（）A
Circulating currents are kept to a minimumB
Field excitation losses are kept to a minimumC
Generator rotors will have a lesser tendency to huntD
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考题
单选题The alternating current generator supplying a load has a voltage drop resulted from the loadWhen the load has a lagging power factor this voltage drop （）.A
is smallB
may be neglectedC
is usefulD
is considerable
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save network costB
improve the reliability of supplying power to important loadC
prevent sequence reverseD
increase the power factor of important load
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governors of both units are adjustedC
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单选题A constant output voltage from an AC generator is maintained by the （）.A
prime mover governorB
exciter generatorC
voltage regulatorD
reverse power relay
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