A turbo-generator has a rated output of 1200...

Question 1 / 270705eccefa4bacbc34ba4d48144

Question 1 of 270705eccefa4bacbc34ba4d48144

A turbo-generator has a rated output of 1200 kW at 60 Hertz, with a no load frequency of 61.5 Hertz. What is its speed droop?

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Question 1 of 27070

A turbo-generator has a rated output of 1200 kW at 60 Hertz, with a no load frequency of 61.5 Hertz. What is its speed droop?

🔍 Key Concepts

• Speed droop definition in governing systems (percent change in speed from no-load to full-load relative to rated speed) • Relationship between frequency and speed in synchronous generators • How to express a change as a percentage of rated frequency

💭 Think About

• First, determine how much the frequency changes between no-load and rated load conditions. Is the machine faster or slower at no-load? • Decide which value you should use as the reference (denominator) when computing percent droop: no-load frequency or rated/load frequency? • Once you compute the percentage, compare it to the choices and think about whether the size of that percentage makes sense for a typical governor droop on a turbo-generator.

✅ Before You Answer

• Be sure you subtract in the correct direction: no-load frequency minus rated/load frequency • Use rated/load frequency as the base when you calculate the percentage, not the no-load value • Confirm that your final percentage is in the same order of magnitude as common governor droops (typically a few percent, not tenths of a percent)

Question 1 of 27070

A turbo-generator has a rated output of 1200 kW at 60 Hertz, with a no load frequency of 61.5 Hertz. What is its speed droop?

1.025%

1.500%

2.439%

2.500%