EE6603: POWER
EE6603: POWER SYSTEM OPERATION ASYSTEM OPERATION AND CONTROLND CONTROL REGULAT REGULATION - ION - 20132013 UNIT I: INTRODUCTION UNIT I: INTRODUCTION PART A: PART A: 1.
1. DeDefifine sne spipinninning rng resesererveve.. 2.
2. WhaWhat is mt is meant eant by loby load frad frequequency cency contontrolrol?? 3.
3. What aWhat are the re the advantaadvantages of ges of pool oppool operatieration witon with resh respect tpect to L!?o L!? ".
". WhaWhat is tht is the use of see use of seconcondary ldary loop in oop in #L#L! sys! systemtem?? $.
$. DeDefifine ne coconnennectcted ed loloadad?? %.
%. What is tWhat is the role of che role of computeomputers in the oprs in the operatieration and conton and control of powrol of power syser system?tem? &.
&. WhWhat at is is loload cad cururveve?? '.
'. WhWhat at is is babase se loloadad?? (.
(. DeDefifine ne loload ad fafactctoror.. 1).
1). What is the need for load forWhat is the need for load forecastecasting?ing? 11.
11. What is tWhat is the need for voltage he need for voltage regulation in power regulation in power systems?systems? 12.
12. List the advantList the advantages of multi area operatages of multi area operation.ion. 13.
13. DefinDefine diversity facte diversity factor.or. 1".
1". What is the effWhat is the effect of load factor on tect of load factor on the cost of generation?he cost of generation? 1$.
1$. DefinDefine the term ae the term average lverage load.oad. 1%.
1%. What is syWhat is system lestem level controvel controll 1&.
1&. What are the What are the effects of effects of variable load in variable load in power systempower system 1'.
1'. What is tWhat is the ob*ective of he ob*ective of power system controlpower system control 1(.
1(. What is tWhat is the necessity of he necessity of frequency regulation in frequency regulation in power system.power system. 2).
2). What is tWhat is the difference bethe difference between load curve and lween load curve and load duration curve.oad duration curve. 21.
21. What are the difWhat are the differeferent types of loadnt types of load 22.
22. What is the signifWhat is the significance of load factor and diversiicance of load factor and diversity factor.ty factor. 23.
23. DefDefine loaine load.d.
2".Write down the quadratic and e+ponential equation 2".Write down the quadratic and e+ponential equation PART B:
PART B: 1.
1. i, Defii, Define the follne the following- 1owing- 1, /ot res, /ot reserve 2, !oerve 2, !old reserld reserve 3, diveve 3, diversity frsity factor actor ii,# generating station has the following daily load
ii,# generating station has the following daily load cycle- cycle-0
0iimme e iin n hhrrss,, ))%% %%11)) 11))1122 112211%% 11%%22)) 22))22"" L
LooaaddWW,, 22)) 22$$ 33)) 22$$ 33$$ 22)) Draw the load curve and
Draw the load curve and calculate ma+imum demand units generated per calculate ma+imum demand units generated per day averageday average load load factor.
load load factor. 2.
2. 4+plai4+plain the foln the followinlowing- i, Loag- i, Load forecd forecastinasting ii, 4cg ii, 4conomic donomic dispatcispatch contrh control.ol. 3.
3. i, 4+pli, 4+plain the folain the followinlowing terms- 5g terms- 5nstalnstalled reseled reserve spirve spinning resnning reserve colerve cold reserved reserve hot hot reserve.
reserve.
ii,# power station has to meet the following ii,# power station has to meet the following demand-6roup #-2))7W between ' #. and
6roup #-2))7W between ' #. and % 8.% 8. 6roup 9-1))7W between % #. and
6roup 9-1))7W between % #. and 1) #. 6roup !-$)7W between % #. and 11) #. 6roup !-$)7W between % #. and 1) #.) #. 6roup D-1))7W between 1) #. and
6roup D-1))7W between 1) #. and % 8.% 8. and and then between % then between % 8.8. and % #.. 8lot and % #.. 8lot the daily load curve
the daily load curve and determine diversity factor units generated per day and loadand determine diversity factor units generated per day and load factor.
factor. ".
systems. ii, Write short notes on load forecasting.
$. i,What is meant by chronological load curve? 6ive the information obtained from load curves.
ii,4+plain the advantages and different types of computer control system. %. Describe briefly about plant level and system level control.
&. i, what are the information obtained from load curve and load duration curve?
ii, 9riefly describe the importance of load forecasting and e+plain the method of least square fit forecasting the base load.
'. What are ob*ectives of modern trend in real time control of power system? 4+plain the significant features of computer control in power system.
(. i, with neat s:etch describe the pf and ;< control structure. ii, 4+plain the following terms
i. a+imum Demand ii. 8lant use factor iii. 8lant capacity factor iv. =eserve capacity
1). i, 4+plain the need for voltage and frequency regulation in power system
ii, # generating station has ma+imum demand of ")) W. 0he annual load factor is %$> and capacity factor is $)> find the reserve capacity of the plant.
11. Draw load curve and load duration curve. 4+plain the importance of these curves in connection with economic operation of power system
12. # generating station has ma+imum demand of 2) W load factor is %)> and capacity factor is $)> find the reserve capacity of the plant daily energy produced ma+imum energy that could be produced daily if the plant were running all the time and ma+imum energy that could be produced if the plant when runningacc. 0o operating schedule, were fully loaded.
UNIT II: REAL POWER- FREQUENCY CONTROL PART A:
1. tate the advantages of state variable model. 2. What is #6!?
3. What are the conditions necessary for sharing load operating in parallel between the two synchronous machines?
". Define area control error.
$. What are the classification of system load? %. What is meant by load frequency control.
&. Why the frequency and voltage to be regulated in a power system?
'. !ompare the functions of @speed 6overnorA and @ speed changerA in a speed governing systems of a turbine generator set.
(. What do you understand by coherent group of generators?
1). # speed governor system cannot completely eliminate frequency error caused by a step load change in power system. Bustify this statement.
11. /ow is the real power in power system controlled? 12. What is meant by free governor operation?
13. What is the function of load frequency control on a power system? 1". Define speed droop.
1$. Draw the dynamic responses of change in frequency for a step load change for single area system
1&. What is meant #=!
1'. tate whether changes in #<= loop will be reflected in #L! loop. 1(. List the advantages of multi area operation.
2).4+plain the principle of tie line bias control. PART B:
1. 0wo synchronous generators operating in parallel. 0heir capacities are 3))W and "))W. 0he droop characteristics of their governors are "> and $> from no load to full load. #ssuming that the generators are operating at $)/C at no load how would be a load of %))W shared between them. What will be the system frequency at this load? #ssume free governor action.
2. Develop the state variable model of a two area system and state the advantages of the model.
3. Draw the bloc: diagram of uncontrolled two area load frequency control system and e+plain the salient features under static condition.
". /ow is speed governor mechanism modeled? 4+plain its operations with the speed load characteristics.
$. Derive the transfer function model and draw the bloc: diagram for single control area provided with governor system. rom the transfer function derive the e+pression for
steady state frequency error for a step load change.
%. What are the components of speed governor system of an alternator? Derive its transfer function with an aid of a bloc: diagram.
&. 4+plain the dynamic response of single area load frequency control.
'. 0wo 1)))7W alternators operate in parallel. 0he speed regulation of first alternator is 1))> to 1)3> from full load to no load and that of other 1))> to 1)$>. /ow will the two alternators share load of 12))7W and at what will one machine cease to supply any portion of the load.
(. or a system regulation "/EFp.u.W7 p1$) 0 p1'secG8)).)1p.u.ind the dynamic
response of uncontrolled case. #lso derive the equation used.
1). Derive the e+pression for steady state frequency change for single area system with the following cases.
i,!hanges in load with fi+ed speed ii,changes in speed with fi+ed demand
11. i, Determine the primary #L! loop parameters for a control area having the following data.
0otal rated area capacity 8r2)))W. Hormal operating load 8d1)))W.
5nertia constant /$.)
=egulation =2.") /EFpu W all area generators,
We shall assume that the load frequency dependency as linear meaning that the old load would increase 1> for 1> frequency increase.
ii, /ighly brief the importance of regulating frequency and voltage of the power system.
12. 4+plain the static and dynamic characteristics of single area control system.
Init3
REACTIVE POWER–VOLTAGE CONTROL1. What are the merits and demerits of synchronous compensator?
2. What are the various methods of voltage control in transmission system? 3. What are the various functions of e+citation system?
". how the voltage control and reactive power control are interrelated. $. 6ive the function of #<=.
%. tate difference between 8f and ;< controls.
&. What are the methods to improve the voltage profile in the power system. '. What is the need for the compensator in the #<= loop.
(. What is meant by stability compensation?
1). Draw the root loci for Eero compensated loops. 11. !ompare shunt and series capacitor.
12. Discuss the effect of compensation on the ma+imum power transfer in a transmission line. 13. What is <!? Why is it used.
1". Draw the phasor diagram of <!.
1$. /ow is voltage control obtained by using tap changing transformerF 1%. What are the methods of voltage controlF
1&. What are the different types of <!F
1'. What is booster transformer? Where is it used? Pa!-B
1. Describe various methods of voltage control and e+plain any three in detail.
2. Draw the diagram of a typical automatic voltage regulator and develop its bloc: diagram representation.
3. i, Hame the generators and consumers of reactive power in a power system. ii, What are static <#= compensators? tate the advantages of <.
". 4+plain the following methods of voltage control i, 0ap changing transformers ii, hunt reactors iii, ynchronous phase modifiers iv, hunt capacitors v, series capacitors.
$. Draw the circuit for a typical e+citation system and derive the transfer function model and draw the bloc: diagram.
%. What are the different methods of voltage control? 4+plain any two methods in detail. &. i, Develop a typical e+citation arrangement to control the voltage of an alternative
and e+plain. 9riefly e+plain the role of tap changing transformer in voltage control? '. What is tatic <#= compensator? Where is it used? 4+plain its operation. #lso state the
merits of static <#= compensator over the other methods of voltage control. (. i,Discuss in brief about generation and absorption of reactive power.
ii, Derive the relations between voltage power and reactive power at a node for applications in power system control.
1). Describe the various methods of reactive power control and e+plain any two in detail. Discuss static and dynamic analysis of #<=.
Init"
COMMITMENT AND ECONOMIC DISPATC"
Pa!-A
1. What is meant by L#!?
3. Draw the incremental fuel cost curve. ". What is meant by spinning reserve?
$. Write the significance of Init !ommitment.
%. Draw the incremental cost curve of a thermal power plant.
&. Write the equality and inequality constraints considered in the economic dispatch problem.
'. Define spinning reserve constraint in unit commitment problem. (. What is incremental cost criterion?
1). What is minimum up and minimum down time in unit commitment problem? 11. Define participation factor.
12. What is participation factor with respect to economic load dispatch 13. Write the coordination equation ta:ing losses into account.
1". What is meant by incremental cost curve?
1$. !ompare with unit commitment and 4conomic load dispatch 1%. Define penalty factor
1&. List the few constraints that are accounted in unit commitment problem 1'. What is meant by priority list method
1(. ention the assumption made in the formation of loss formula matri+ 9. 2). What are the advantages of using forward dynamic programming method 21. tate unit commitment problem.
22. Define incremental efficiency
23. What is difference between load frequency controller and economic dispatch controller
Pa!-B
1. tate the unit commitment problem. With the help of a flow chart e+plain forward dynamic programming solution method of unit commitment problem.
2.0he fuel inputs per hour of plants 1 and 2 are given as 1 ).2812J")81J12)=sFhr
2).2$822J3)82J1$)=sFhr
Determine the economic operating schedule and the corresponding cost of generation. 0he ma+imum and the minimum loading on each unit are 1))W and 2$W. #ssume the transmission losses are ignored and the total demand is 1')W. #lso determine the saving obtained if the load is equally shared by both the units.
3. i, With the help of low chart e+plain 4conomic dispatch by K 5teration method without loss.
ii, 0he fuel cost of two units are given by 11 861, 1.$J2)861J).18612 =shr
22 862, 1.(J3)862J).18622=shr
5f the total demand on the generator is 2)) W. ind the economic load scheduling of the two units.
iii, What is the significance of equality and inequality constraints in the formulation of optimum dispatch problem?
". i, What is unit commitment problem? Discuss the constraints that are to be accounted in unit commitment problem.
ii, Mbtain the priority list of unit commitment using full load average production cost for the given
data-/eat rate of unit1 /1 $1)J&.2861J).))1"2 8612Whr /eat rate
of unit2 /2 31)J&.'$862J).))1("8622Whr
Init mW, a+W, uel !ost .7,
1 1$) %)) 1.1
2 1)) ")) 1.)
3 $) 2)) 1.2
$. i, 4+plain the unit commitment problem using priority ordering load dispatch.
ii, 4+plain the term N5ncremental Mperating !ostO of power system related with economic dispatch.
%. 0he fuel inputs per hour of plants 1 and 2 are given as 1
).2812J")81J12) =sFhr
2).2$822J3)82J1$)=sFhr
Determine the economic operating schedule and the corresponding cost of generation if the ma+imum and minimum loading on each unit is 1))W and 2$W.#ssume the transmission losses are ignored and the total demand is 1') W. #lso determine the saving obtained if the load is equally shared by both the units.
&. 4+plain various constraints in I! and indicate the steps involved in solving I! by D8 method.
'. ormulate the coordination equations with losses neglected and also e+plain the algorithmic steps of iterative method to find the solution of coordination equations.
#$ i,4+plain the priority list method of solving unit commitment 8roblem. tate merits and limitations of this method.
1). 0he fuel cost functions for three thermal plants in PFh are given by
1).))"8g12J$.38g1J$))
2).))%8g22J$.$8g2J"))
3 ).))(8g32J$.'8g3J2)) where 8g18g28g3 are in W. ind the
optimal dispatch and the total cost when the total load is (2$ W with the following generator limits.
1))WQ8g1Q"$)W
1))WQ8g2Q3$)W
1))WQ8g3Q22$W
11. i,4+plain the forward dynamic programming method of solving unit commitment problem. ii,Develop an iterative algorithm for solving the optimum dispatch equation of an RnR bus power system ta:ing into account the effects of system losses.
12. i,!onstruct the priority list for the units given below.
/1$1)J&.2)81J).))1"2812 .8min1$)W.8ma+%))W. uel
cost1.1=sF9tu.
/231)J&.'$82J).))1("822 .8min1))W.8ma+"))W. uel
cost1.)=sF9tu
/3&'J&.(&83J).))"'2832 .8min$)W.8ma+2))W. uel
cost1.2=sF9tu
ii,Derive the co ordination equation with losses neglected. 13. i, 0he cost characteristics of three plants of a system are
!1).)$812J1&.)81J1%) =sFhour
!2).)%822J1"."82J2)) =sFhour
!3).)'832J(.)83J2") =sFhour Where 818283 are in W.
).)$).1) and ).1$ W per W of generation. ind the optimal dispatch for a total load of 1))W and also its incremental cost of received power.
ii, 0he input output curve characteristics of three units are 1&$)J%."(8g1J).))3$8g12.
2'&)J$.&$8g2J).))1$8g22.
3%2)J'.$%8g3 J).))18g3 2. 0he fuel cost of unit 1 is 1.) =sF9tu 1.) =sF9tu for
unit 2 and 1.) =sF9tu for unit 3. 0otal load is '))W. Ise the participation factor method to calculate the dispatch for a load is increased to '')W?
1". With a neat flow chart e+plain the iterative algorithm for solving the economic dispatch equation of H bus power system ta:ing into account the effects of
system losses.
1$. 0he fuelcost functions for three thermal plants are given by 1).))"8g12J$.38g1J$)) PFhr
2).))%8g22J$.$8g2J")) PFhr
Init$
COMPUTER CONTROL OF POWER SYSTEMS
Pa!-A
1. What are the functions of !#D#? 2. Define state estimation.
3. What is @!#D#A?
". Write any two functions of Load Dispatch !enter. $. Define the 4 system.
%. Define networ: topology in power system.
&. What are the different operating states in power system. '. Distinguish between reliability and security of power system. (. What are the 4 functions?
1). List out the conditions for normal operations of a power system. 11. What do you understand by security constraints?
12. What is contingency analysis program
13. List the factors that affects the power system security
1". What are the typical sensors used in power system application 1$. When is power system considered to be secured?
1%. Define restorative state. 1&. What is normal state?
1'. What are the tas:s of energy control center?
1(. What are the important types of relay used for protection 2). Denote the hierarchical levels used in 4.
21. Write the importance of state estimation in power system. 22. List out the conditions for normal operation of power system. 23. What are the functions of load control centre?
1. 9riefly e+plain various functions of !#D# with neat diagram. #lso list some of the common features of all !#D# systems
2. Discuss the various functions system monitoring and control of load dispatch center. 3. i, What is 4? What are its ma*or functions in power system operation and control?
ii, Draw the bloc: diagram to show the hardware configuration of a !#D# system for a power system and e+plain the application of !#D# in monitoring and control of power system
". 4+plain the security monitoring using state estimation with necessary diagrams.
ii, i,4+plain need of computer control of power system. 4+plain the ma*or functions of system security control.
$ 4+plain various state transitions and control strategies using state transition diagram. % 9riefly discuss the various functions of energy control centre.
& List the various contingencies that are generally considered for steady sate security analysis. 4+plain the ma*or functions of system security control.
' Write short notes on energy control centre 4 and its functions. ( 4+plain the state estimation method in power system.
1) i, 4+plain the networ: topology determination method with the factors involved in it. ii,4+plain the power system security and control with neat flow chart.
11.
iv, v,
vi, vii,
