What is the harm if reverse power flows?

What is the harm if reverse power flows?
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Answer :

Assume that the generator normally produces an amount of power equal to P, and that when operating as a motor, it will absorb a similar amount, P. Therefore, the net effect on the grid will be the same as if it experienced a step increase in load equal to 2P. Depending on the size of the grid and the strength of the remaining generation, a step increase of 2P could result in a significant frequency change on the grid.
There could be prime mover damage in some instances (especially steam turbines).
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Related questions

How do you test reverse power trip, high current trip, preferential trip?

Description : How do you test reverse power trip, high current trip, preferential trip?

Last Answer : Reverse power trip - refer answer for question 11. Also ask E/O. High current (over load trip) - Set your overload relay high current trip setting to say 75% of the rated current. Run the ... loads to overload the generator. Preferential trip will trip all the non-critical loads. Also ask E/O.

Why is this reverse power used instead of reverse current in alternators?

Description : Why is this reverse power used instead of reverse current in alternators?

Last Answer : It is extremely difficult to detect reverse current with an alternating current system, reverse power can be detected and protection can be provided by reverse power relay.

How do you test reverse power trip?

Description : How do you test reverse power trip?

Last Answer : When two generators are running in parallel and one generator can carry the load, reverse power trip can be tested by load shifting using governor control. When the load has shifted sufficiently and the off ... (using the test push button on the relay) to see if it initiates a trip signal.

How is the protection against reverse power given?

Description : How is the protection against reverse power given?

Last Answer : Reverse power protection is used for anti-motoring. This function is used for protection of prime mover not generator. It can cut-off the fuel supply and stop the prime mover.

When does Reverse power flow?

Description : When does Reverse power flow?

Last Answer : Situation of a generator is feeding a system through switchgear having several generators connected in parallel with this generator. The flow of current, when the system is running normally, is from the ... minor to extreme in the event of a complete mechanical failure of the generator which fails.

What is the harm caused by this?

Description : What is the harm caused by this?

Last Answer : Single phasing causes higher than rated currents in the healthy phases of loads such as motors causing over heating of the motor and consequently motor failure. Single phasing can sometimes ... . Motor protection relays for larger motors come readily fitted with protection against single phasing.

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Description : In a transistor, the conventional current flows from base to emitter. The transistor is (a) NPN (b) PNP (c) FET (d) None of these

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A current of 5.8 A flows through a 0.25 m long straight conductor which is kept perpendicular in a region of uniform magnetic field of 3.7 T . The force on conductor is a) 5.4 N b) 2.4 N c) 3.4 N d) 6.4 N

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Last Answer : a) 5.4 N

When the potential difference of 4 volt is applied across resistance, 10J energy is converted. Find the charge flows. a. 0.20 C b. 2.5C c. 5C d. 10C

Description : When the potential difference of 4 volt is applied across resistance, 10J energy is converted. Find the charge flows. a. 0.20 C b. 2.5C c. 5C d. 10C

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If 1 ampere current flows through 2m long conductor the charge flow through it in 1 hour will be a. 3600C b. 7200C c. 1C d. 2C

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Last Answer : (c) Suddenly increases

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Refering to the illustrated schematic diagram, which of the following statements is true when the motor is running in the forward direction? EL-0011 A. Normally-open contacts '4-5' are closed. B. Current flows through the 'Reverse' push-button switch. C. Normally-closed contacts 'R' are open. D. The blowout coils must be closed.

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What is the benefit of improving power factor?

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_______ electric power is the most common method used by electrical grids to transfer power.

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