Ask Question, Ask an Expert

+1-415-315-9853

info@mywordsolution.com

Ask Electrical & Electronics Expert

1) a) The three phase ratings of the three winding transformer are

Primary: Y connected, 110 kV, 20 MVA

Secondary: Y connected 13.2kV, 15 MVA

Tertiary: Δ connected, 2.1 kV, 0.5 MVA

Three short circuit tests carried out on this transformer provides the following results

i) Primary excited, secondary shorted: 2290 V, 52.5 A

ii) Primary excited, Tertiary shorted: 1785V, 52.5 A

iii) Secondary excited, Tertiary shorted: 148 V, 328 A.

Determine the p.u. impedances of star connected single phase equivalent circuit for a base of 20 MVA, 110 kV in the primary circuit.

b) Describe the requirement for the power system analysis in planning and operation.

2) a) A 3- phase transmission line is feeding from the 23/230 kV transformer at its sending end. The line is supplying a 150 MVA, 0.8 pf load through a step down transformer of 230 / 23 kV. The impedance of the line and the transformer is (18+j60) ?. The sending end transformer is energized from the 23 kV supply. Find the tap setting for every transformer to manage the voltage at the load at 23 kV.

b) Deduce the formula that is used in the above problem.

3) A salient pole generator without dampers is rated as 20 MVA, 13.8 kV, and has the direct axis sub transient reactance of 0.25 pu. The negative and zero sequence reactance are 0.35 and 0.10 pu respectively. The neutral of the generator is solidly grounded. Find the sub transient current in generator and the line to line voltage for sub- transient conditions when a single line to ground fault occurs at the generator terminal with the generator operating unloaded at rated voltage. Neglect the resistance.

4) The Y bus matrix for a network is given below

Y bus = {-j5.833     j 2.5     j 3.333
                j 2.5       - j 7.5     j 5
                j 3.333     j 5       -j 8.333}

Find the complex bus bar voltage at the end of first iteration, by using the gauss seidel method. Bus 1 is a slack bus with V1=1.05?0. Bus 2 : PV bus, V2=1.0 pu , Pg =3 pu, Bus 3: PQ bus, P3=4 pu and Q3 = 2 pu.

5) prepare down the algorithm steps for loading the flow solution by using the Newton Raphson method.

6) describe the equal area criterion for transient stability analysis of the system for the modification in the mechanical input.

7) A synchronous generator having a reactance of 1 pu is connected to an infinite bus through a transmission system with a reactance of 0.7 pu. The generator is running on no load with a voltage of 1.1 pu. Consider H = 4.5 MW-s/ MVA. The voltage of infinite bus is 1?0 pu and its frequency is 50 Hz. Determine the frequency of the natural oscillation if machine is abruptly loaded to

i) 60 % and

ii) 75 % of its maximum power limit.

Neglect the resistance and the machine damping.

Electrical & Electronics, Engineering

  • Category:- Electrical & Electronics
  • Reference No.:- M913289

Have any Question? 


Related Questions in Electrical & Electronics

1 what is the significance of a nonzero net right-lateral

1. What is the significance of a nonzero net right-lateral differential of and normal to the z-direction at a point in space? 2. If a pair of E and B at a point satisfies Faraday's law in differential form, does it neces ...

A bug starts at a point and travels 1 m northwardm

A bug starts at a point and travels 1 m northward, m eastward, m southward, m westward, m northward, and so on, making a 90°-turn to the right and halving the distance each time. (a) What is the total distance traveled b ...

1 when we talk about authentication in ipsec do we mean

1. When we talk about authentication in IPSec, do we mean message authentication or entity authentication? Explain. 2. If Alice and Bob are continuously sending messages to each other, can they create a security associat ...

The performance of a journal bearing around a rotating

The performance of a journal bearing around a rotating shaft is a function of the following variables: Q, the rate of flow lubricating oil to the bearing in volume per unit time; D, the bearing diameter; N, the shaft spe ...

Your client wants a quick design for a system to pump on

Your client wants a quick design for a system to pump on the order of 1800 gallons per day from a depth of 200 ft. You decide to use a 45-V submersible pump with an estimated efficiency of 35% along with PV modules havin ...

1 two point charges each of mass m and charge q are

1. Two point charges each of mass m and charge q are suspended by strings of length l from a common point. Find the value of q for which the angle made by the strings at the common point is 90°. 2. Point charges Q and ar ...

1 distinguish message authentication and entity

1. Distinguish message authentication and entity authentication. 2. Alice signs the message she sends to Bob to prove that she is the sender of the message. Which of the following keys does Alice need to use? a. Alice's ...

The power output of a hydraulic turbine depends on the

The power output of a hydraulic turbine depends on the diameter D of the turbine, the density ρ of water, the height H of water surface above the turbine, the gravitational acceleration g, the angular velocity ω of the t ...

Question 1a for the circuit shown in figure 1 sketch the

Question 1. (a) For the circuit shown in FIGURE 1 sketch the voltage waveform across the secondary winding of the transformer. On the same diagram sketch the load voltage waveform. The sketches should take into account d ...

1 describe the phasor technique of solving a differential

1. Describe the phasor technique of solving a differential equation for the sinusoidal steady-state solution. 2. State Coulomb's law. To what law in mechanics is Coulomb's law analogous? 3. What is the definition of the ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro

Describe what you learned about the impact of economic

Describe what you learned about the impact of economic, social, and demographic trends affecting the US labor environmen