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
EBK POWER SYSTEM ANALYSIS AND DESIGN
- A synchronous generator is rated 645 MVA, 24 kV, 0.9 pf lagging. It has a synchronous reactance 1.2 . The generator is feeding full load at 0.9 pf lagging at rated voltage. Calculate: (a) Excitation emf (E,) and power angle & (b) Reictive power drawn by the load Carry out calculations in pu form and convert the result to actual values.arrow_forwardA three phase round rotor synchronous generator, 16 kV, 200 MVA with an inductance of X,= 1.65 pu, is connected to an infinite busbar at 15 kV. It delivers 100 MVA at 0.8 pf lagging Determine excitation voltage E, load angle and current delivered. Calculate the load angle and reactive power delivered if the field current is reduced by 10% and the real power input remains constant. iii) ş The prime mover is then adjusted without changing excitation such that the machine delivers zero reactive power. Determine the new load angle and the real power delivered. Determine the maximum reactive power that the machine can deliver at the level of excitation in ii) above. unchronous generators to bearrow_forward(c) A star connected 3 phase wound field synchronous generator with a synchronous reactance of 202 is connected to a 6.6 kV (phase voltage) grid and supplies 1.5 MW at 0.95 lagging power factor at its terminals. Calculate the phase current and resultant voltage across the synchronous reactance (Vxs), and from a scaled phasor diagram graphically determine the required excitation voltage (En) and load angle (5).arrow_forward
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- Power System Analysis and Design (MindTap Course ...Electrical EngineeringISBN:9781305632134Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. SarmaPublisher:Cengage Learning