Reference no: EM131004941
1. You have a power system that consists of a generator, 01, connected to a three-phase step-up delta-to-wye transformer (with neutral grounded), T1, which is connected to a transmission line, LI, which is connected to a three-phase step-down wye-to-delta (wye not grounded) transformer, T2, which is connected to a synchronous motor, MI, that is currently offline. The positive, negative and zero sequence impedance of the generator, GI, is 0.15, 0.15 and 0.05, respectively. Initially, assume that GI has its neutral solidly connected to ground. The transformer T1 has positive, negative and zero sequence impedance given by 0.1, 0.1 and 0.15 respectively. The transmission line, LI, has positive, negative and zero sequence impedance given by 0.1, 0.1 and 0.15 respectively. The transformer 1'2 has positive, negative and zero sequence impedance given by 0.05, 0.05 and 0.1 respectively.
a. Draw the sequence networks for this power system.
b. Assume a SLG fault occurs just beyond the low side of T2. Draw the sequence networks with connections resulting from this fault and solve for the fault current.
c. Assume a SLG fault occurs just before the high side of T2. Draw the sequence networks with connections resulting from this fault and solve for the fault current.
d. Assume a SLG fault occurs right in the middle of the transmission line, LI. Draw the sequence networks with connections resulting from this fault and solve for the fault current.
e. Assume a SLG fault occurs just beyond the high side of T1. Draw the sequence networks with connections resulting from this fault and solve for the fault current.
f. Assume a SLG fault occurs just before the low side of T1. Draw the sequence networks with connections resulting from this fault and solve for the fault current.
2. Repeat problem 1 but this time assume that the generator, GI, has its neutral connected to ground through a 0.02 resistance.
3. Repeat problem 1 but this time assume that the generator, GI, has its neutral connected to ground through a 0.02 reactance.
4. Discuss the effect on fault current magnitude with respect to the three ways that the neutral of generator GI was connected to ground.
Helpful Hints: See the TransformersZeroSequence.pdf file attached . Also, when a generator is connected to ground through impedance, Zg, then the zero sequence network has an impedance of 3Zg added in series with its zero sequence impedance, 4.
Attachment:- TransformersZeroSequence.pdf
|
Plotted on the vertical axis and q on the horizontal axis
: Suppose a firm faces the following demand for its output q: q = a + bp, where p represents the price it receives per unit sold. Let α be the x-intercept of this demand curve (p plotted on the vertical axis and q on the horizontal axis). Let β be the ..
|
|
What is the role of auditors in attesting to sea data
: What is "overlapping debt" and why is it important to financial analysts and others who use government financial statements?
|
|
Sample workforce activity
: As a sample workforce activity, assume your employer has asked you to develop an economic analysis and a set of policy recommendations. To complete this activity, select a news article dated within the previous two months. Clearly summarize the issue..
|
|
Describe the components of time cost in health care
: Respond to each of the following questions (150-200 words each) that apply the economic concepts described in this topic's assigned readings in The Economics of Health and Medical Care. Write the formula for price elasticity of demand and describe..
|
|
Draw the sequence networks for power system
: Draw the sequence networks for this power system and draw the sequence networks with connections resulting from this fault and solve for the fault current.
|
|
Develop a general model for predicting long-run market share
: A company is trying to predict the long-run market share of a new men's deodorant. Based on initial marketing studies, they believe that 35% of new purchasers in this market will ultimately try this brand. Develop a general model for predicting long-..
|
|
Find the slope of the tangent line to the curve
: Using the definition of the derivative, find the slope of the tangent line to the curve at the point (5, f(-5)). Write the equation of the tangent line to the curve at the point (5, f(-5)).
|
|
The economic advisor to a local government
: Suppose that you are the economic advisor to a local government that has to deal with a politically embarrassing surplus that was caused by a price floor that the government recently imposed. Your first suggestion is to get rid of the price floor, bu..
|
|
One of the criticisms of oligopolies is the adverse impacts
: One of the criticisms of oligopolies is the adverse impacts these firms have on income distribution. Do you believe that is a valid criticism? Discuss with appropriate examples.
|