ay iCHAPTER 1 :- INTRODUCTION
1.1 Problem summary
Electrical power system is back bone of the development of a nation. There is big issue of power quality for developed nations but the developing countries like India the load is increasing rapidly but generation is not up to the level of demand. Hence there is need of load flow management. Load flow analysis using software is accurate and gives highly reliable results. This research makes effective use of The Power World to carry out load flow analysis of power station. This Wanakbori TPS is located in Kheda district operated by Gujarat State Electricity Corporation Limited (GSECL).
The major cause of almost all power system disturbances is under voltage, voltage drops and power factor. In order to identify and pinpoint these disturbances, load flow studies are conducted. The result of these studies help to address the system disturbances with the help of additional devices (capacitors etc.).
Short circuits can occur anywhere in the system. In order to protect the system against short circuits, it is necessary to install circuit breakers which can safely isolate the circuit in fault conditions. The results of these studies help in proper selection & settings of protective device such as fuses, circuit breakers, and relays used in the protection scheme. Thus helping utilities maintain a safe, reliable and efficient electrical distribution system.
The single line diagram of the substation is simulated in Power World Simulation based upon actual data, and it is seen that at the 220kV, 400kV buses there is under voltage. To overcome the under voltage at the 220kV, 220kV buses capacitor bank of suitable ratings are added.
This Report presents a new and efficient methodology for network reconfiguration with optimal power flow. The objective minimizes the power losses, balancing load among the feeders and subject to the constraints: capacity limit of the branches, minimal and maximal limits of the substation or generator, minimum deviation of the nodes voltages and radial operation of the networks
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1.2 Aim and objective of the project
Load flow analysis taken here for case study is with reference to 220kV and 400 kV Wanakbori TPS, Kheda. A single line diagram is prepared using Power World software. The data required for the network, some of which are taken from 220kV and 400 kV Wanakbori TPS. Entered in the Power World database. Objective of the project is given below:
To monitor and analyze the power system accurately.
To overcome the under voltage problem.
To expand the substations in future demand.
To improve the power factor of power system.
To minimize the losses of power system.
1.3 Brief literature review and prior art search
Power system engineering mainly deals with the concept of study and analysis of power system and the electrical generated power has to be transmitted and distributed to the consumer’s with specified quality and reliability as and when consumers need.
The application of software tools for power system studies has been increasing over the years. After the development of powerful computer based software and the recent advances in engineering sciences have brought a revolution in the field of electrical engineering. This work deals with the use of Power World software for load flow analysis of large electrical power system which comprises of large power distribution network emanating of 220 kV and 400 kV Wanakbori TPS.
The load flow studies determine whether the system voltage remains within the specified limits under various contingency conditions, and any overloading of equipment such as transformers and conductors. Load-flow studies are also used to find any need for additional generation, capacitive, or inductive var support, or the placement of capacitors and/or reactors to maintain system voltage within specified limits.
The load flow analysis using Power World software provides reliable and accurate results. The Power World software performs numerical calculations of large integrated power system with fabulous speed besides generating output parameters. This study makes use of Power World software to carry out load flow analysis of 220 kV and 400 kV Wanakbori TPS. The actual ratings of Power Transformers, Circuit Breakers, Current Transformers, Potential Transformers and Isolating switches are modeled in Power World Software.
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Patent search analysis
According to literature survey after studying various IEEE paper, collected some related patents some of the point describe here;
1. “Simulation and Analysis of 220kV Substation”
Yogesh Patel1, Dixit Tandel, Dharti Katti.
The main objective of this thesis is to simulate and analyze the 220 KV Substations. The simulation and analysis includes power flow analysis and short circuit analysis. Power flow study also known as load flow constitutes an important part of power system analysis and design of any power system network. The power flow analysis and short circuit analysis is done in the Power World Simulator Software. For the power flow analysis using the single line diagram of 220 KV substations, the model of the substation is developed in the Power World Simulator. The different kinds of faults are also simulated at various buses of the substation. Power World Simulator is very useful software for analyzing power system operation. By doing the power flow analysis in the Power World Simulator we estimate the real and reactive power flows, power losses in the entire network and phase angle using Power World Simulator. Short circuit analysis is also useful to select, set, and coordinate protective equipment such as circuit breakers, fuses, relays, and instrument transformers. Simulation technique is very useful in the power system planning and design.
2. “Load Flow and Short Circuit Study of 220 kV Substation”
Nirav Taunk, Gaurang Sharma.
Short Circuit Analysis provides the information required to determine if the interrupting capacities of the power system components are adequate enough to protect your power system. Load flow is basic requirement to conduct the short circuit analysis of any system. The load flow gives us the sinusoidal steady state of the entire system – voltages, real and reactive power generated and absorbed and line losses. In this study, we have carried short circuit study of 220 kV substation system using PSAT software. From the PSAT generated report, load flow and short circuit system are studied.
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1.4 Introduction About Power World Software
User‐friendly and highly interactive power system analysis and visualization platform.
Integrates many commonly performed power system tasks –
Contingency Analysis, Time‐Step Simulation, OPF, ATC, PVQV, Fault Analysis, SCOPF, Sensitivity Analysis, Loss Analysis, Transient Stability, GIC etc.
Designed to operate on Microsoft Windows XP/2003/Vista/2008/7/8 platforms.
Provide a better understanding of how to use Power World Simulator for power system analysis and visualization.
Provide techniques for building good power system models and show how these techniques can be used to analyze system issues.
Primary Goal: Make you aware of the capabilities of Simulator
o We are frequently asked to add features to Simulator that are already available.
o We want you to make the most of our software.
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CHAPTER 2 :- Load Flow Study
2.1 Basic of Load Flow
For equations we assume that system is operating in balance load condition and 1-phase model in used. Four equations are associated with each bus. These are voltage magnitude, for the solution of the any load flow equation we are assume the following assumption.
Balanced load in all the 3 phases.
Active and reactive power demand of each bus given to you.
Voltage sinusoidal at 50Hz.
In solving the power flow equations we assume that system is operating in balance load condition and 1-phase model is used. Four equations are associated with each bus. These are voltage magnitude, phase angle, real power, and reactive power. But for the solution of the problem we have only two equation and at each bus there are four unknown variables so to solve the equation we divides the all the system buses into three types.
1. Slack Bus
2. Load Buses
3. Regulated Buses
Slack Bus
Usually this bus is numbered 1 for the load flow studies. This bus sets the angular reference for all the other buses. Since it is the angle difference between two voltage sources that dictates the real and reactive power flow between them, the particular angle of the slack bus is not important. However it sets the reference against which angles of all the other bus voltages are measured. For this reason the angle of this bus is usually chosen as 0°. Furthermore it is assumed that the magnitude of the voltage of this bus is known.
Load Buses
In these buses no generators are connected and hence the generated real power PGi and reactive power QGi are taken as zero. The load drawn by these buses are defined by real power -PLi and reactive power -QLi in which the negative sign accommodates for the power flowing out of the bus. This is why these buses are sometimes referred to as P-Q bus. The objective of the load flow is to find the bus voltage magnitude |Vi| and its angle δi.
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Regulated Buses
These are the buses where generators are connected. Therefore the power generation in such buses is controlled through a prime mover while the terminal voltage is controlled through the generator excitation. Keeping the input power constant through turbine-governor control and keeping the bus voltage constant using automatic voltage regulator, we can specify constant PGi and | Vi | for these buses. This is why such buses are also referred to as P-V buses. It is to be noted that the reactive power supplied by the generator QGi depends on the system configuration and cannot be specified in advance. Furthermore we have to find the unknown angle δi of the bus voltage.
The two most commonly used methods for the load flow studies are Gauss-Seidel method and Newton-Raphson method. An approximate but easy solution is possible if some simplifying assumptions are made. These are listed below,
a. Line resistance is neglected which means that the active power loss in the lines is zero. This reduces the complexity of the equation because total active power generation equal to the total active power demand.
b. All buses accepted the swing bus is voltage-controlled bus. This means the voltage of all buses is specified. c. The angle (Δi) is small so that sin (Δi) = Δi. This approximation converts the non-linear load flow equations into the linear once so that analytical solution is possible.
2.2 Load Flow Studies
The goal of a power flow study is to obtain complete voltage angle and magnitude information for each bus in a power system for specified load and generator real power and voltage conditions. Once this information is known, real and reactive power flow on each branch as well as generator reactive power output can be analytically determined Due to the nonlinear nature of this problem, numerical methods are employed to obtain a solution that is within an acceptable tolerance.
The solution to the power flow problem begins with identifying the known and unknown variables in the system. The known and unknown variables are dependent on the type of bus. A bus without any generators connected to it is called a Load Bus. With one exception, a bus with at least one generator connected to it is called a Generator Bus. The exception is one arbitrarily selected bus that has a generator. This bus is referred to as the Slack Bus.
The load flow study in a power system constitutes a study of paramount importance. The study reveals the electrical performance and power flows for specified conditions when the system is operating under steady state. The load flow study also provides information about
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the line and transformer loads throughout the system and voltages at different points in the system for evaluation and regulation of the performance of the power system under condition known a priori. Further alternative plants for future expansion to meet new load demands can be analyzed and complete information is made available through this study.
The two most commonly used methods for the load flow studies are Gauss-Seidel method at the slack bus and Newton-Raphson method and also fast decoupling.
2.3 Method of Load Flow Analysis
2.3.1 Gauss-Seidel Method
The (GS) method to solve a load flow problem we consider two cases depending on the type of bus present. In first case we assume all the buses other than the slack bus are PQ buses. In the second case we assume the bus present of both PQ and PV buses other than the slack bus.
The Gauss-Seidel (GS) method is an iterative algorithm for solving a set of non-linear algebraic equations. To start with, a solution vector is assumed, based on guidance from practical experience in a physical situation. One of the equations is then used to obtain the revised value of a particular variable by substituting in it the present values of the remaining variables. The solution vector is immediately updated in respect of this variable. The process is then repeated for all the variables thereby completing one iteration. The iterative process is then repeated till the solution vector converges within prescribed accuracy. The convergence is quite sensitive to the starting values assumed. Fortunately, in a load flow study a starting vector close to the final solution can be easily identified with previous experience.
The slack bus voltage being specified, there are (n-1) bus voltage starting values of whose magnitudes angle are assumed. These values are then updated through an iterative process. During the course of any iteration, the revised voltage at the ith bus is obtained.
The advantages of this method are:
(1) Small computer memory requirement.
(2) The simplicity of the technique.
(3) Less computational time per iteration.
The disadvantages of this method are:
(1) Slow rate of convergence and therefore, large number of iteration.
(2) Increase of number of iterations directly with the increase in the number of buses.
(3) Effect on convergence due to choice of slack bus.
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2.3.2 Newton Raphson Method
The NR method a powerful method of solving non-linear algebraic equation. It works faster and is sure to converse in most cases as compared to the gauss-siedel (GS) method. It is indeed the practical method of load flow solution of large power network. Its only drawback is the large requirement of computer memory which can be overcome through a compact storage scheme. Convergence can be considerably speeded up by performing the first iteration through the GS method and using the values so obtained per solving the NR iteration. So time taken for each iteration by NR method is more compared to the GS method converges in only a few iteration and the total commutation time is much less than the GS method.
The advantages of this method are:
1) More accuracy and surety of convergence.
2) Only about 3 iteration are required as to more than 25 or so as required by G-S method.
3) The number of iteration is almost independent of the system.
Newton-Raphson method can be apply to the load-flow problem in the no ways the most common being those using
o Rectangular co-ordinates
o Polar co-ordinates
2.3.3 Fast Decoupled Method
The fast decoupled load flow (FDLF) was developed by B. Stott in 1974. The assumptions which are valid in normal power system operation are made as follows:
1) Under normal loading conditions, angle differences (𝛿i – 𝛿k), its across transmission lines are small, I.e. cos (𝛿i -𝛿k) = 1, sin (𝛿i – 𝛿k) = 0
2) For a transmission line, its reactance is more than its resistance. In other words, X/R >>1. So, Gik can be ignored because Gik << Bik.
In view of the above, Gik sin (𝛿i – 𝛿k) << Bik and Qi << BiiVi2.
With these assumptions, the elements of H and L sub-matrices become considerably simplified as 𝑯𝒊𝒊=∂𝑃𝑖∂δ𝑖= −𝐵𝑖𝑖𝑉𝑖2 (𝑖=𝑘)…(1) 𝑯𝒊𝒌=∂𝑃𝑖∂δ𝑘= −𝐵𝑖𝑘𝑉𝑖 𝑉𝑘(𝑖≠𝑘)…(2)
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𝑳𝒊𝒊=𝑽𝒊∂𝑄𝑖∂δ𝑖= −𝐵𝑖𝑖𝑉𝑖2 (𝑖=𝑘)…(3) 𝑳𝒊𝒌=𝑽𝒌∂𝑄𝑖∂V𝑘= −𝐵𝑖𝑘𝑉𝑖 𝑉𝑘(𝑖≠𝑘)…(4)
Substituting Equations (1) and (2) in eq. below Σ𝐻𝑖𝑘Δ𝛿𝑘=Δ𝑃𝑖(𝑖=2,3,…,𝑁𝐵),𝑊𝑒 ℎ𝑎𝑣𝑒𝑁𝐵𝑘=2 Σ(−𝐵𝑖𝑘𝑉𝑖 𝑉𝑘)Δ𝛿𝑘=Δ𝑃𝑖(𝑖=2,3,…,𝑁𝐵)𝑁𝐵𝑘=2 Σ(−𝐵𝑖𝑘 𝑉𝑘)Δ𝛿𝑘=Δ𝑃𝑖𝑉𝑖 (𝑖=2,3,…,𝑁𝐵)𝑁𝐵𝑘=2…(5)
Setting Vk = 1 p.u. on R.H.S. of eq. Σ(−𝐵𝑖𝑘 )Δ𝛿𝑘=Δ𝑃𝑖𝑉𝑖 (𝑖=2,3,…,𝑁𝐵)𝑁𝐵𝑘=2
Substituting Equations (3) and (4) in eq. below Σ𝐿𝑖𝑘Δ𝑉𝑘𝑉𝑘=Δ𝑄𝑖(𝑖=𝑁𝑉+1,𝑁𝑉+2,…,𝑁𝐵),𝑊𝑒 𝑔𝑒𝑡𝑁𝐵𝑘=𝑁𝑉+1 Σ(−𝐵𝑖𝑘𝑉𝑖 𝑉𝑘)Δ𝑉𝑘𝑉𝑘=Δ𝑄𝑖(𝑖=𝑁𝑉+1,𝑁𝑉+2,…,𝑁𝐵)𝑁𝐵𝑘=𝑁𝑉+1
Or Σ(−𝐵𝑖𝑘)Δ𝑉𝑘=Δ𝑄𝑖𝑉𝑖 (𝑖=𝑁𝑉+1,𝑁𝑉+2,…,𝑁𝐵)𝑁𝐵𝑘=𝑁𝑉+1…(6)
Eq. (5) and (6) can be written in matrix form as, [𝐵][Δ𝛿]=[Δ𝑃𝑉] [𝐵][Δ𝑉]=[Δ𝑄𝑉]
Where
B’ is the matrix having element -Bik (I=2, 3, …, NB and k=2, 3, … , NB)
B” is the matrix having element -Bik (I= NB+1, NB+2, …, NB and k= NB+1, NB+2, … , NB).
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2.3.4 Decoupled Load Flow Studies
Transmission lines of power systems have a very low R/X ratio. For such system, real power mismatch ΔP are less sensitive to changes in the voltage magnitude and very sensitive to changes in phase angle Δ𝛿. Similarly, reactive power mismatch ΔQ is less sensitive to changes in angle and very much sensitive on charges in voltage magnitude. Therefore, it is reasonable to set elements J2 and J3 of the Jacobain matrix to zero. Therefore, Equation reduces to [Δ𝑃Δ𝑄]=[𝐽100𝐽4][Δ𝛿Δ|𝑉|]
Or
Δ𝑃 = 𝐽1 Δ𝛿
Δ𝑄 = 𝐽4 Δ|𝑉|
For voltage controlled buses, the voltage magnitudes are known. Therefore, if m buses of the system are voltage controlled, J1 is of the order (n-1) x (n-1) and J4 is of the order (n-1 -m) x (n-1 -m).
Now the diagonal elements of J1 are ∂𝑃𝑖∂δ𝑖=Σ|𝑉𝑖||𝑉𝑘||𝑌𝑖𝑘|sin(𝜃𝑖𝑘−𝛿𝑖+𝛿𝑘)𝑛𝑘=1𝑘≠𝑖
The off-diagonal elements of J1 are ∂𝑃𝑖∂δ𝑘=|𝑉𝑖||𝑉𝑘||𝑌𝑖𝑘|sin(𝜃𝑖𝑘−𝛿𝑖+𝛿𝑘)𝑘≠𝑖
The diagonal elements of J4 are ∂𝑄𝑖∂|V𝑖|=−2|𝑉𝑖||𝑌𝑖𝑖|sin(𝜃𝑖𝑖)−Σ|𝑉𝑘||𝑌𝑖𝑘|sin(𝜃𝑖𝑘−𝛿𝑖+𝛿𝑘)𝑛𝑘=1𝑘≠𝑖 ∂𝑄𝑖∂|V𝑖|=−|𝑉𝑖||𝑌𝑖𝑘|sin(𝜃𝑖𝑘−𝛿𝑖+𝛿𝑘)𝑘≠𝑖
The terms ΔPi(p) and ΔQi(p) are the difference between the scheduled and calculated values at bus I know as power residuals, given by
ΔPi(p) = Pischeduled – Pi(p)(calculated)
ΔQi(p) = Qischeduled – Qi(p)(calculated)
The new estimates for bus voltage magnitudes and angle are,
|Vi|(p+1) = |Vi|(p) + Δ|Vi|(p) δ𝑖 (p+1) =δ𝑖(p) +δ𝑖 (p)
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CHAPTER 3 :- Case Study
3.1 Introduction about Wanakbori TPS.
Wanakbori Thermal Power Station is a coal-fired power station in Gujarat, India. It is located on the bank of Mahi River in Kheda district. There are seven units of each 210 MW capacity.
GSECL has recently entrusted BHEL with an order for setting up an 800-MW supercritical coal-based project at Wanakbori in Gujarat on EPC basis.
Stage
Unit Number
Installed Capacity (MW)
Date of Commissioning
Status
Stage I
1
210
March 1982
Running
Stage I
2
210
January, 1983
Running
Stage I
3
210
March, 1984
Running
Stage II
4
210
March, 1986
Running
Stage II
5
210
September 1986
Running
Stage II
6
210
November 1987
Running
Stage II
7
210
December 1998
Running
Stage III
8
800
–
Under Construction
Table 1:- Number of Unit in Wanakbori TPS
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Figure 1:- Single Line Diagram of 220 kV Wanakbori TPS
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Figure 2:- Single Line Diagram of 400 kV Wanakbori TPS
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3.2 Data Collection
Line Details
Name Of Line
De-rated MVA
Number of Circuit
Length of Line in km
Positive Sequence Resistance
Positive Sequence Reactance
For 220 kV line
kapadvanj 1
200
D/C
35.47
0.0800
1.0402
kapadvanj 2
200
D/C
35.47
0.0800
1.0402
Asoj
200
D/C
63.00
0.0800
1.0402
Vyankntpura
200
D/C
63.00
0.0800
1.0402
Godhara
200
S/C
35.00
0.0748
0.3992
Dhansura 1
200
D/C
58.90
0.0800
0.4020
Dhansura 2
200
D/C
58.90
0.0800
0.4020
For 400 kV line
Asoj
712
S/C
76.00
0.02979
0.332
Dehgam
712
S/C
67.54
0.02979
0.332
Soja
712
S/C
95.10
0.02979
0.332
Table 2:- Line Detail
Name Of Line
Zero Sequence Resistance
Zero Sequence Reactance
For 220 kV line
kapadvanj 1
0.2190
1.350
kapadvanj 2
0.2190
1.350
Asoj
0.2190
1.350
Vyankntpura
0.2190
1.350
Godhara
0.2199
1.339
Dhansura 1
0.2180
1.350
Dhansura 2
0.2180
1.350
For 400 kV line
Asoj
0.1620
1.24
Dehgam
0.1624
1.24
Soja
0.1624
1.24
Table 3:- Line Detail
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Load Details
Name
MW
Mvar
Power Factor
For 220 kV line
kapadvanj 1
94
10
0.99
kapadvanj 2
98
15
0.99
Asoj
42
10
0.99
Vyankntpura
28
11
0.99
Godhara
161
3
0.99
Dhansura 1
90
00
0.99
Dhansura 2
90
00
0.99
For 400 kV line
Asoj
31
65
0.99
Dehgam
350
-4
0.99
Soja
236
36
0.99
Table 4:- Load Detail
Two Winding Transformer Details
220 kV
400 kV
ITEMS
GT-1
GT-2
GT-3
GT-4
GT-5
GT-6
GT-7
De-rated MVA
250
250
250
250
250
250
250
From Bus
Bus-1
Bus-2
Bus-3
Bus-1
Bus-2
Bus-3
Bus-4
To Bus
Bus-4
Bus-4
Bus-4
Bus-5
Bus-5
Bus-5
Bus-5
MVA
250
250
250
250
250
250
250
Primary Rating (kV)
15.75
15.75
15.75
15.75
15.75
15.75
15.75
Secondary Rating (kV)
220
220
220
400
400
400
400
Min. Tap No. (OLTC)
1
1
1
1
1
1
1
Max. Tap No. (OLTC)
18
18
18
18
18
18
18
Connection
YN/d11
YN/d11
YN/d11
YN/d11
YN/d11
YN/d11
YN/d11
Table 5:- Two Winding Transformer Details
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Generator Details
ITEMS
GENERATOR
MVA Rating
247
Mvar Rating
130.0346
MW Rating
210
kV Rating
15.75
Table 5:- Generator Details
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3.3 Output Report Of Load Flow Analysis
3.3.1 Live System Data of 220 kV of Wanakbori TPS
Figure 3:- Load Flow Diagram of 220 kV Wanakbori TPS
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Load Flow Report of 220 kV Wanakbori TPS
From
To
MW
Mvar
MVA
Bus-1
G-1
183.35
24.70
185.0
Bus-2
G-2
210.00
25.75
211.6
Bus-3
G-3
210.00
25.75
211.6
Bus-1
Bus-4
183.35
24.70
185.0
Bus-2
Bus-4
210.00
25.75
211.6
Bus-3
Bus-4
210.00
25.75
211.6
Bus-4
Bus-1
-183.35
-17.85
184.2
Bus-4
Bus-2
-210.00
-16.80
210.7
Bus-4
Bus-3
-210.00
-16.80
210.7
Bus-4
Bus-5
47.02
5.21
47.3
Bus-4
Bus-6
49.02
7.76
49.6
Bus-4
Bus-7
21.00
5.05
21.6
Bus-4
Bus-8
14.00
5.52
15.1
Bus-4
Bus-9
161.20
4.05
161.2
Bus-4
Bus-10
45.02
0.08
45.0
Bus-4
Bus-11
45.02
0.08
45.0
Bus-5
Bus-4
-47.00
-4.97
47.3
Bus-5
Kapadvanj 1
94.00
10.00
94.5
Bus-6
Bus-4
-49.00
-7.50
49.6
Bus-6
Kapadvanj 2
98.00
15.00
99.1
Bus-7
Bus-4
-21.00
-5.00
21.6
Bus-7
Asoj
42.00
10.00
43.2
Bus-8
Bus-4
-14.00
-5.50
15.0
Bus-8
Vyankantpura
28.00
11.00
30.1
Bus-9
Bus-4
-161.00
-3.00
161.0
Bus-9
Godhara
161.00
3.00
161.0
Bus-10
Bus-4
-45.00
00.00
45.0
Bus-10
Dhansura 1
90.00
00.00
90.00
Bus-11
Bus-4
-45.00
00.00
45.0
Bus-11
Dhansura 2
90.00
00.00
90.00
Table 7:- Load Flow Report of 220 kV Wanakbori TPS
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Load Flow Summary
ITEMS
MW
Mvar
Total Load
603.0
49.0
Total Generation
603.3
76.2
Total losses
0.3
27.3
Table 8:- Load Flow Summary of 220 kV Wanakbori TPS
Conclusion
For live system the total real power generation is 603.3 MW and total reactive power generation is 76.2 Mvar. So, Generation power factor is 0.9921. Total real power load is 603.3 MW and total reactive power load is 49.0 Mvar. So, Load power factor is 0.9967.
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3.3.2 Live System Data of 400 kV of Wanakbori TPS
Figure 4:- Load Flow Diagram of 400 kV Wanakbori TPS
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Load Flow Report of 400 kV Wanakbori TPS
From
To
MW
Mvar
MVA
Bus-1
G-4
-11.51
26.54
28.9
Bus-2
G-5
210.00
26.45
211.7
Bus-3
G-6
210.00
26.45
211.7
Bus-4
G-7
210.00
26.45
211.7
Bus-1
Bus-5
-11.51
26.54
28.9
Bus-2
Bus-5
210.00
26.45
211.7
Bus-3
Bus-5
210.00
26.45
211.7
Bus-4
Bus-5
210.00
26.45
211.7
Bus-5
Bus-1
11.51
-26.53
28.9
Bus-5
Bus-2
-210.00
-25.56
211.5
Bus-5
Bus-3
-210.00
-25.56
211.5
Bus-5
Bus-4
-210.00
-25.56
211.5
Bus-5
Bus-6
30.97
65.11
72.1
Bus-5
Bus-7
351.37
0.09
351.4
Bus-5
Bus-8
236.15
38.00
239.2
Bus-6
Bus-5
-30.95
-64.93
71.9
Bus-6
Asoj
31.00
65.00
72.0
Bus-7
Bus-5
-351.00
-4.00
351.0
Bus-7
Dehgam
351.00
-4.00
351.0
Bus-8
Bus-5
-235.98
-36.10
238.7
Bus-8
Soja
236.00
36.00
238.7
Table 9:- Load Flow Report of 400 kV Wanakbori TPS
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Load Flow Summary
ITEMS
MW
Mvar
Total Load
618.0
97.0
Total Generation
618.5
105.9
Total losses
0.6
8.9
Table 10:- Load Flow Summary of 400 kV Wanakbori TPS
Conclusion
For live system the total real power generation is 618.5 MW and total reactive power generation is 105.9 Mvar. So, Generation power factor is 0.9856. Total real power load is 618.0 MW and total reactive power load is 97.0 Mvar. So, Load power factor is 0.9879.
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CHAPTER 4 :- Project Summary
From the load flow analysis on 220 kV and 400 kV Wanakbori TPS by using power world software we can say that we can check all the condition like real power generation, real power load, reactive power generation, reactive power load, generation power factor, load power factor, losses in each line of the system.
Summary of Result
Load Flow Analysis of 220 kV Wanakbori TPS
Load Flow Analysis of 400 kV Wanakbori TPS
Total Real Power Generation (MW)
603.3
618.0
Total Reactive Power Generation (Mvar)
76.2
105.9
Generation P.F.
0.9921
0.9856
Total Real Power Load (MW)
603.0
618.0
Total Reactive Power Load (Mvar)
49.0
97.0
Load P.F.
0.9967
0.9879
Table 11:- Load Flow Summary
From the study of Load Flow Analysis
By load flow analysis the Mvar loading capacity of the line. In spite of large no. of load flow methods available, it is easy to see that Fast De-coupled load flow methods is most important ones for general purpose load flow analysis by using Power World Software.
The Fast De-coupled method is steel in use because of its high accuracy, reliability and versatility and, as such is being widely used for variety of system optimization calculations.
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CHAPTER 5:- Future Scope
Load flow analysis is one of the most common computational procedures used in power system analysis. The load flow problem can be defined as: Given the load power consumption at all buses of a known electrical power system configuration and the power generation at each generator, find the power flow in each line and transformer of the inter-connected network and the voltage magnitude and phase angle at each bus.
From the result load flow we can study stability of system and transient stability. Also the reliability study for the load flow by making one generator off or making one line off below information obtained from load flow studies.
a) Magnitude and phase angle of voltage at each bus with reference to swing bus voltage.
b) Real and reactive power flowing in each line.
c) Study the line parameter calculation from the study and reduce the cost.
Such a condition occurs a heavy current flow through the equipment causing considerable damage to the equipment and intrusion of service to the consumers.
This software is also solve another different method by NR method, fastn here…