a.
The value of
a.
Answer to Problem 11.1P
The value of synchronous angular radial frequency is
The value of synchronous angular velocity of rotor is
Explanation of Solution
Given:
A three-phase steam turbine-generating unit having
Frequency,
MVA rating,
Rated voltage,
Poles,
Inertia constant,
Formula Used:
The synchronous angular radial frequency is expressed as,
Where
The synchronous angular velocity of rotor is expressed as,
Where
Calculation:
To determine the value of synchronous angular radial frequency
To determine the value of synchronous angular velocity of rotor
Conclusion:
The value of synchronous angular radial frequency is
The value of synchronous angular velocity of rotor is
b.
The kinetic energy in joules stored in the rotating mass a synchronous speed.
b.
Answer to Problem 11.1P
The kinetic energy in joules stored in the rotating mass at synchronous speed is
Explanation of Solution
Given:
A three-phase steam turbine-generating unit having
Frequency,
MVA rating,
Rated voltage,
Poles,
Inertia constant,
FormulaUsed:
The kinetic energy in joules stored in the rotating mass at synchronous speed is expressed by
Where
Calculation:
To calculate the value of kinetic energy in joules stored in the rotating mass at synchronous speed, substitute the values of
Conclusion:
The kinetic energy in joules stored in the rotating mass at synchronous speed is
c.
The
c.
Answer to Problem 11.1P
The mechanical angular acceleration is
Explanation of Solution
Given:
A three-phase steam turbine-generating unit having
Frequency,
MVA rating,
Rated voltage,
Poles,
Inertia constant,
Accelerating power,
FormulaUsed:
The power swing equation is expressed as,
Where
The mechanical angular acceleration is expressed as,
Where
Calculation:
Assume the base power to be 500 MW.
So the per unit accelerating power
And the per unit angular frequency
Now, rearrange the equation (3) for
To calculate the value of mechanical angular acceleration, substitute the values in equation (4)
Conclusion:
The mechanical angular acceleration is
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Chapter 11 Solutions
Power System Analysis and Design (MindTap Course List)
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- Power System Analysis and Design (MindTap Course ...Electrical EngineeringISBN:9781305632134Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. SarmaPublisher:Cengage Learning