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International Journal of JOURNAL Electrical Engineering and Technology (IJEET), ISSN 0976 – INTERNATIONAL OF ELECTRICAL ENGINEERING 6545(Print), ISSN 0976 – 6553(Online) Volume 4, Issue 2, March – April (2013), © IAEME & TECHNOLOGY (IJEET)

ISSN 0976 – 6545(Print) ISSN 0976 – 6553(Online) Volume 4, Issue 2, March – April (2013), pp. 202-218 © IAEME: www.iaeme.com/ijeet.asp Journal Impact Factor (2013): 5.5028 (Calculated by GISI) www.jifactor.com

IJEET ©IAEME

OPTIMAL DG PLACEMENT USING MULTIOBJECTIVE INDEX AND ITS EFFECT ON STABILITY AND FIELD RELAYS Dr.T.Ananthapadmanabha1, H Pradeepa2, Likith Kumar. M. V 3, Maruthi Prasanna.H.A.3, Veeresha.A.G.3, Pradeep N4 1

Professor, Dept of EEE, NIE, Mysore, Karnataka, India. Asst. Professor, Dept of EEE, NIE, Mysore, Karnataka, India. 3 Research Scholar, Dept of EEE, NIE, Mysore, Karnataka, India. 4 Lecturer, Dept of EEE, Govt. Polytechnic, Karwar, Karnataka, India. 2

ABSTRACT As the yearly electric energy demand grows, there is a significant increase in the penetration of distributed generation (DG) to fulfil this increase in demand. Increase in the number of DG is partly attributed to the new deregulated environment and the advent of new concepts as the smart grid. Penetration of a DG into an existing distribution system has many impacts on the system, with the power system protection being one of the major issues. DG causes the system to lose its radial power flow, besides the increased fault level of the system caused by the interconnection of the DG. Short circuit power of a distribution system changes when its state changes. This may result in elongation of fault clearing time and hence disconnection of equipments in the distribution system or unnecessary operation of protective devices. This paper presents a Multiobjective performance index (MOI) for distribution networks with distributed generation which considers a wide range of technical issues for optimal placement of DG. Distributed generation is extensively located on the IEEE-9Bus test feeder, IEEE-33Bus Radial Distribution Feeder and Practical 24Bus Distribution Feeder Located at Hassan. The Transient Stability studies are carried out by plotting terminal voltage, frequency and swing curve of DG with respect to main grid. From this we found critical clearing time and angle which is useful for relay co-ordination. The Directional and Non-Directional Over Current Relay Co-ordination (OCR) is carried out for radial 9-Bus radial system by considering without and with DG placement. Keywords: Distributed Generation (DG), Multi objective index (MOI), MiPower, Over Current Relay Co-ordination (ORC).Single line Diagram (SLD). 202

International Journal of Electrical Engineering and Technology (IJEET), ISSN 0976 – 6545(Print), ISSN 0976 – 6553(Online) Volume 4, Issue 2, March – April (2013), © IAEME

I. INTRODUCTION Traditional Concept of Power Systems Electricity generation is produced in large power plants, usually located close to the primary energy source (for instance: coil mines) and far away from the consumer centres. Electricity is delivered to the customers using a large passive transmission and distribution infrastructure, which involves high voltage (HV), medium voltage (MV) and low voltage (LV) networks. These distribution networks are designed to operate radially. The power flows only in one direction: from upper voltage levels down-to customers situated along the radial feeders. New Concept of Power Systems technologies allow the electricity to be generated in small sized plants. In this new conception, some of the energy-demand is supplied by the centralized generation and another part is produced by distributed generation. The electricity is going to be produced closer to the customers [1], [2] Faults generally results in high current levels in electrical power systems. These currents are used to decide the occurrence of faults and require protection devices, which may differ in design depending on the complexity and accuracy necessary. The ordinary type of protection devices are thermo-magnetic switches, moulded-case circuit breakers (MCCBs), fuses, and over-current relays. Amongst these types, over-current relay is the most common protection device used to counteract excessive currents in power systems [3]. An over-current protection relay is a device able to sense any change in the signal, which it is receiving normally from a current and/or voltage transformer and carry out a specific operation in case that the incoming signal is outside a predetermined range. Usually the relay operates closing or opening electrical contacts, as for example the tripping of a circuit breaker [4], [5]. In this paper case study and their results are presented. Cases gives a solution to the optimal location of DG considering IMO for same rating of DG with Lag, Lead and Unity power factor for standard radial test system and also for practical distribution system. We studied the terminal voltage, frequency and swing curve of DG w.r.t. main grid by conduction 3phase to ground fault at buses by using MiPower software [6]. Finally we discussed and proposed a solution of relay co-ordination to a 9bus radial system with and without DG, considering directional and non-directional relays using MiPower software. II. PROBLEM STATEMENT Nowadays, the use of renewable sources of energy has reached greater importance as it promotes sustainable living and with some exceptions (biomass combustion) does not contaminant. Renewable sources can be used in either small-scale applications away from the large sized generation plants or in large-scale applications in locations where the resource is abundant and large conversion systems are used. Nevertheless, problems arise when the new generation is integrated with the power distribution network, as the traditional distribution systems have been designed to operate radially, without considering the integration of the new generation in the future. In radial systems, the power flows from upper terminal voltage levels down to customers situated along the radial feeders .Therefore, over-current protection in radial systems is quite straightforward as the fault current can only flow in one direction. With the increase of penetration of DG, distribution networks are becoming similar to transmission networks where generation and load nodes are mixed (“mesh” system) and more complex protection design is needed. In this new configuration, design considerations 203


regarding the number, size location and technology of the DG connected must be taken into account as the short circuit levels are affected and miss coordination problems with protection devices may arise. We carried out Relay co-ordination for radial 9 Bus system by placing directional relays and Non directional relays without DG connected and after addition of DG as affects both the coordination as well as the instantaneous high current setting of the primary and backup relays. The Plug, Time and instantaneous settings were calculated and relay coordination was carried with addition of DG. We tried to investigate transient stability of the power system while the test system was subjected to a particular fault. In that case, the test system was investigated by applying a fault to a specific distribution line and at the buses afterwards it was assumed that the fault had been cleared by tripping the faulty line after certain fault duration. Then by plotting the behavior of the DG rotor angle, voltage and frequency w.r.t main generator the critical clearing time and angle will be noted down. III. PERFORMANCE INDICES A set of indices is proposed to quantify some of the technical benefits of DG. They are ILp, ILq, IVD, ISC1 and ISC3.[1] A.

Real and Reactive Power Loss Index (ILp and ILq )

The major potential benefit offered by DG is the reduction in electrical line losses. The loss can be significant under heavy load conditions. With the inclusion of DG, line loss in the distribution system can be reduced. Obviously, line-loss reductions are due to reductions in power flows resulting from the introduction of DG. However, depending on the ratings and locations of DG units, it is possible to have an increase in lo(and unrealistic) penetration levels. The first two indices (ILp & ILq) [1] express respectively as, ILp k = 1 −

Re{Losses k } Re{Losses 0 }

....… (1) ILqk = 1 −

Im{Lossesk } Im{Losses0 }

…… (2) Where lossesk is the total complex power losses for the kth distribution network configuration, and losseso is the total complex power losses for the distribution network without DG. B.

Voltage Drop Index (IVD)

One advantage of careful location and sizing of DG is the enhancement of the voltage profile. By introducing DG in the system, voltage profile can be improved because DG can provide a portion of the real and reactive power to the load, thus helping to decrease 204


current along a section of the distribution line, which, in turn, will result in a boost in the voltage magnitude at the customer site.  VΦ 0 − VΦ ki IVD k = 1 − max  VΦ 0 

Where Φ

 NN −1   i=1 

…… (3) are the phases a, b, and c; VΦ 0 are the voltages at the root node (equal in

magnitude for the three phases); Φ ki are the voltages at node i for the kth distribution network configuration; and NN is the number of nodes. C. Three-Phase and Single-Phase-to-Ground Short Circuit Short-Circuit currents introduce potentially destructive energy in the form of heat and magnetic forces in a power system. Historically the distribution network has been designed to accommodate power flow from the grid supply points downward through tiers of networks operating at lower voltage to the electricity consumers. The ISC3 and ISC1 are related to the protection and selectivity issues since they evaluate the maximum short-circuit current variation between the scenarios with and without DG. These indices give the power engineer a notion of how the DG impacts on the protection devices that were planned for a network without such generation units. Hence, a low impact on this concern means close-to-unity values for ISC3 and ISC1 indices[1] ISC 1

k

I   SCabc 0  i  = 1 − max  I  k  SCabc   i 

…….. (4)   ISC 3 k = 1 − max    

 SCabc 0  i   I SCabc k  i  I

………. (5) Where I

SCabc ki

is the three-phase fault current value in node i for the kth distribution network

configuration, I is the three-phase fault current value in node for the distribution SCabc 0 i

network without DG. IV. PROBLEM FORMULATION A Multiobjective performance index for the performance calculation of distribution systems for DG location is proposed in this work. It considers all previously mentioned indices by strategically giving a weight for each one. This could be performed, since all impact indices are normalized (values between 0 and 1). The weighting factors are chosen based on the importance and criticality of the different loads and according to the objectives

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of the system operator that may be assigned from the power quality measures and components capabilities of the power system. The Multiobjective performance index [1] is given by:

w1ILp k + w2 ILq k + w3IVD k  IMO =   + w4 ISC1k + w5ISC 3k  k

5 ∑ wi = 1.0 Λ wi ∈ [0,1] i =1 ……….. (6)

Multiobjective performance index for networks with DG takes into account all indices by strategically giving a weighting factor to each one. This allows them to be related and a unique index to indicate the extent of DG impact, in a global manner, on a distribution network. These relevance factors are intended to give the corresponding importance to each technical issue (impact indices) due to the presence of DG and depend on the required analysis (e.g., planning, regular operation, emergency operation). Furthermore, the relevance factors should be flexible since electric utilities present different concerns about losses, voltages, protection schemes, etc. This flexibility makes the proposed methodology even more suitable as a tool for finding the most beneficial places where DGs may be inserted, regarding the electric utilities’ technical perspective and, consequently, regarding the DG owner’s economic perspective since utilities may incentivize (or even disincentives) connections points that are more beneficial based on the technical impacts. V. SIMULATION STUDY AND RESULTS A. TYPICAL RADIAL DISTRIBUTION SYSTEM The system under study is nine-bus radial distribution test system typical distribution system with a generator connected to a grid.

Fig.5.1 Single-line diagram of radial system A total load of 0.8375 pu (on a 400 MVA base) is located unevenly at various buses and there are 8 transmission lines. First load flow is conducted from this total real power, reactive power losses and voltages at all the buses are noted down. Then by conducting short circuit 206


faults at all the buses (SLG and 3PH-G) short circuit currents are noted down. Placing the DG at bus-2 again load flow analysis and short circuit analysis are conducted then by placing DG at each different bus at each location the above induces are calculated. After finding all indices valves by giving relevant weighing factors total MOI is calculated.

Fig.5.2 Single line diagram of Radial 9bus system drawn in MiPower Software

Fig.5.3 Graph of ILp& ILq Index

Fig.5.4 Graph of Voltage Drop Index The optimal location of Distributed Generator by considering Multiobjective index (MOI) is Bus-8.The above DG considered is of 0.05 pu on 400 MVA base with 0.9 pf. i.e. 18MW & 8.717Mvar. The optimal location of DG for lagging power factor will be at bus-6 and for unity power factor will be at bus-8. 207


Fig.5.5 Graph of Single phase to ground fault & three phase to ground fault index

Fig.5.6 Graph of Total Multi objective index valves at each bus

Fig.5.7 Graph of Total Multi objective index valves by considering different power factor for rating of DG

B. PRACTICAL DISTRIBUTION SYSTEM The Hassan distribution sub-station is located on the Banglore-Manglore road. It has undergone many changes in the past few decades. In this system, the 220 kV bus is being tapped which is running from Shimoga main receiving station to Mysore receiving station. Another line runs from Hassan to Nittur. The 220 kV is stepped down to 66 kV by using two 100 MVA power transformers. Then it is again stepped down by using a 20 MVA and 12.5MVA transformers in MUSS, Santhepet, Hassan. At present there are 11 feeders which distribute power to Hassan town and surrounding areas. Out of these 11 feeders a particular feeder known as Water Works feeder is taken for analysis.

208


Fig.5.8: Simplified Water Works Feeder Network

Fig.5.9 Graph of Total Multi objective index valves at each bus for 24-bus system The optimal location of Distributed Generator by considering Multiobjective index (IMO) is Bus-19. C. ANALYSIS OF TERMINAL VOLTAGE, FREQUENCY AND SWING CURVES OF DG For NINE bus system the optimal location of DG is at Bus-8 Case-1: Three Phase to ground fault near Grid Starting at 1 sec and clearing at 2.33 sec system is stable (1.33 sec).

Fig.5.10 Swing Curve of DG w.r.t. Grid (1-2.33sec)

Fig.5.11 Generator terminal voltage of DG w.r.t. Grid (1-2.33sec) 209


Fig.5.12 Frequency of DG w.r.t. Grid (1-2.33sec) The three phase to ground fault is applied at bus-1 fault is initiated at 1 sec and cleared at 2.33 sec. The rotor angle of DG w.r.t Grid plot is as shown in fig.5.10. The terminal voltage and frequency behaviour is shown in fig.5.11 and fig.5.12 respectively, system is stable.

Fig.5.13 Swing Curve of DG w.r.t. Grid (1-2.34sec)

Fig.5.14 Generator terminal voltage of DG w.r.t. Grid (1-2.34sec)

Fig.5.15 Frequency of DG w.r.t. Grid (1-2.34sec) The three phase to ground fault is applied at bus-1 fault is initiated at 1 sec and cleared at 2.34 sec. The rotor angle w.r.t Grid plot is as shown in fig.5.13. The terminal voltage and frequency behaviour is shown in fig.5.14 and fig.5.15 respectively, system is unstable.

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From the above figures we can conclude that when fault near grid the critical clearing time is more than the fault near DG. The rotor angle of DG will swings more when fault near DG than near grid. By knowing Critical clearing time (cct) and critical clearing angle (cca) we can analyse the generators behaviour, voltage stability range and frequency stability. If the swing range of DG w.r.t grid crosses 1800 in positive or negative direction then system will lose its synchronism and leads system to instability. The cct and cca will indicate the over current relay operating time near to grid and or DG, for case 1 when fault near grid the relay should operate with in by 1.33 sec if it fails to operate then the system will be unstable and DG loses its synchronism. D. OVER CURRENT RELAY CO-ORDINATION FOR 9 BUS RADIAL DISTRIBUTION SYSTEM Referring to Figure 1, the 9-bus radial system, we will do over current relay (OCR) co-ordination for last feeder for the bus 1, 4, 6, 8.The assumption is done because even if fault occurs near bus 3, 5, 7, 9 it will not effect for last feeder part i.e. for bus 4, 6, 8. Directional over current relay Co-ordination for Last feeder of 9bus without DG

Fig.5.16 Directional OCR Co-ordination for last feeder without DG

Fig.5.17 Curves for Directional OCR Co-ordination for last feeder without DG The last feeder of 9 bus is as shown in above Fig.5.16 SLD was developed in MiPower software. To do relay co-ordination we need fault current at the buses, by conducting 3phase to ground fault at all the buses the fault currents at each buses is as shown in figure 5.16.

211


Since one source is present the fault current will flow from source to load. Here Relay R2 acts back up for R3, R1 is back up for R2 when fault occurs near line3 i.e. between bus3 and bus4 R3 will acts instantaneously and isolate the faulty section if this relay fails to sense and not trip then R2 will acts as a backup relay the time of operation for R3 is 0.1 sec if it fails to operate then after a certain delay R2 will sense and trip at 0.5215sec.If fault occurs at line2 R2 will acts instantaneously at 0.25sec. When it fails then R1 will trip at 0.9296 sec as backup relay for R2.Similarly if fault at line1 R1 will trip at 0.4 sec instantaneously. Fault near line2 R2 should operate if R3 trips it leads to mal operation.

PRIM RELAY

RELAY TYPE

OP.TIME REMOTE FAULT(SEC) 2138. 00

R2

OP.TIME FOR CLOSE IN FAULT(SEC) 0.9296 0.5215

DOES NOT BACKUP

R1

CLOSE IN FAULT CURRENT(A) 3396.6 1 2923.0 5

5900. 00

CDAG31P(NI) CDAG31P(NI)

***

T.D.S 0.4 0.25

50

7100. 00

0.1

50

PLUG SETTING PRIM(A)

100

0.41

PLUG SETTING (%)

R2

50

0.23

CT PRIM CHOOSEN (Amps)

175

0.05

RELAY NAME R1

50

R3

RESULT

CDAG31P(NI)

Directional over Current Relay Co-ordination for Last feeder for 9bus with DG

Fig.5.18 Directional OCR Co-ordination for last feeder with DG

Fig.5.19 Curves for Directional OCR Co-ordination for last feeder with DG

212


0.8624

3800.00

R2

R2

50

100

0.290

0.20

2923.05

0.4789

6500.00

R1

R3

50

50

0.050

0.05

5500.00

****

R4

50

50.00 0.600

0.40

DOES NOT BACK-UP 317.37 1.6104

636.00

R5

R5

50

50.00 0.450

0.25

313.28

630.00

R6

R6

50

50.00 0.300

0.10

620.00

****

1.2147

DOES NOT BACK-UP

RELAY TYPE

OP.TIME REMOTE FAULT(SEC)

3396.61

PRIM RELAY

OP.TIME FOR CLOSE IN FAULT(SEC)

0.35

T.D.S

0.45


100

PLUG SETTING (%)

100

CT PRIM CHOOSEN (Amps)

R1

RELAY NAME

CLOSE IN FAULT CURRENT(A)

Result:

CDAG31P(NI) CDAG31P(NI) CDAG31P(NI) CDAG31P(NI) CDAG31P(NI) CDAG31P(NI)

The above results are of directional OCR co-ordination for last feeder of 9bus by connecting DG As previously discussed in results for Fig5.18 and 5.19 the relays only sense one flow of direction of fault current. After connecting DG at last bus then the radial behaviour of system will change then flow of fault current will be in both direction magnitude will depend on the level of contribution of grid and generator. The Relay co-ordination setting should be such that w.r.t DG relay R5 should be acts backup to R6 and R4 backup to R5 these requirements is important because the fault contribution level of DG fault current will be decreasing for far away fault from DG. R1, R2, andR3 acts as Directional relay for fault current flowing from grid. R4, R5 and R6 acts as directional relay for fault current flowing from DG. Directional over current relay Co-ordination for Middle feeder for 9bus without DG

Fig.5.20 Directional OCR Co-ordination for middle feeder without DG

213


Fig.5.21 Curves for Directional OCR Co-ordination for Middle feeder without DG

RELAY TYPE 31P(NI) 31P(NI) 31P(NI)

31P(NI)

PRIM RELAY R2 R4 ****

R3

OP.TIME REMOTE FAULT(SE C) 4560.00 6800.00 6000.00 2000.00

OP.TIME FOR CLOSE IN FAULT(SE C) 0.7764 0.3820

1.1448

CLOSE IN FAULT CURRENT (A) 3224.72 2924.54 DOES NOT BACK-UP

380.36

T.D.S 0.4 0.25 0.05

0.55

PLUG SETTING PRIM(A) 0.460 0.250 0.050

0.630

PLUG SETTING (%) 120.00 73.00 50.00

93.00

CT PRIM CHOOSEN (Amps) 100 50 50

50

R3 R4

R2

R1

RELAY NAME

Result:

Directional over Current Relay Co-ordination for Middle feeder for 9bus with Distributed Generator

Fig.5.22 Directional OCR Co-ordination for middle feeder with DG 214

1.0835

628.00

R6

31P(NI)

635.00

R7

31P(NI)

0.45

0.55

1.4911

0.340

0.470

313.28

73.00

73.00

215

Fig.5.23 Curves for Directional OCR Co-ordination for Middle feeder with DG 31P(NI)

R5

620.00

0.6723

308.94

0.35

0.160

120.00

50

R6

31P(NI)

****

31P(NI)

****

2000.00

DOES NOT BACKUP

DOES NOT BACKUP

610.00

0.05

0.050

50.00

50

R4

0.25

0.050

160.00

50

R5

31P(NI)

R4

6000.00

0.3820

2924.54

0.20

0.250

73.00

50

R3

31P(NI)

R3

6800.00

0.7764

3224.72

0.30

0.460

120.00

50

R2

31P(NI)

R2

4560.00

1.1448

3803.36

0.40

0.630

93.00

100

R1


PLUG SETTING (%)

CT PRIM CHOOSE N (Amps)

RELAY NAME

RELAY TYPE

PRIM RELAY

OP.TIME REMOTE FAULT(S EC)

OP.TIME FOR CLOSE IN FAULT(S EC)

CLOSE IN FAULT CURREN T(A)

T. D. S

316.23

50

R7

50

R8


Result:

R1, R2, R3 and R4 acts as Directional relay for fault current flowing from grid. R5, R6, R7 and R8 acts as directional relay for fault current flowing from DG.


For fault at line 4 R4 will acts instantaneously if fails to operate R3 will acts after a certain delay but R8 will act for contribution of fault current from DG. The relay setting should be such that R1 acts back up to R2, R2 for R3 and R3 for R4 for fault contribution from main generator. R8 acts back up for R7, R7 backup for R6 and R6 backup for R5 for contribution of fault current from DG. VI. CONCLUSION By introducing DG in the system, voltage profile can be improved because DG can provide a portion of the real and reactive power to the load locally, thus helping to decrease current along a section of the distribution line, which, in turn, will result in a boost in the voltage magnitude at the customer site. The proposed Weighting factors are flexible since electric utilities have different concerns about losses, voltages, protection schemes, etc. By knowing Critical clearing time (cct) and critical clearing angle (cca) we can analyse the generators rotor angle behaviour voltage stability range and frequency stability. Integration of the feeder with the DG adds another current source to the whole system. This affects both the coordination as well as the instantaneous high current setting of the primary and backup relays. VII. REFERENCES [1] Luis F. Ochoa, Student Member, IEEE, Antonio Padilha-Feltrin, Member, IEEE, and Gareth P. Harrison, Member, IEEE “Evaluating Distributed Generation Impacts with a Multiobjective Index” IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 21, NO. 3, JULY 2006 [2] Pathomthat Chiradeja, Member, IEEE, and R. Ramakumar, Life Fellow, IEEE “An Approach to Quantify the Technical Benefits of Distributed Generation” IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 19, NO. 4, DECEMBER 2004. [3] Hussein. A. Attia, M. El-Shibini, Z.H. Osman, and Ahmed A. Moftah “An Assessment of a Global Performance Index for Distributed Generation Impacts on Distribution Systems” Proceedings of the 14th International Middle East Power Systems Conference (MEPCON’10), Cairo University, Egypt, December 19-21, 2010, Paper ID 310. [4] T.MashauS.KibaaraS.ChowdhuryS.P.Chowdhury, “Impact of Distributed Generation on Protection Coordination in a Radial Distribution Feeder” UPEC 2011 · 46th International Universities' Power Engineering Conference · 5-8th September 2011 · Soest · Germany. [5] Impact of distributed generation on distribution system by Angel FernándezSarabia June 2011 Aalborg, Denmark [6] PRDC Technical Document and MiPower Manual. [7] Dr.T.Ananthapadmanabha, MaruthiPrasanna.H.A, Veeresha.A.G and LikithKumar. M. V, “A New Simplified Approach for Optimum Allocation of a Distributed Generation Unit in the Distribution Network for Voltage Improvement and Loss Minimization”, International Journal of Electrical Engineering & Technology (IJEET), Volume 4, Issue 2, 2013, pp. 165 - 178, ISSN Print : 0976-6545, ISSN Online: 0976-6553.

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AUTHORS’ DETAIL

Dr. T. Ananthapadmanabha received the B.E. degree in Electrical Engineering in 1980, M.Tech degree in Power Systems (1st Rank) in 1984 and Ph.D. degree (Gold Medal) in 1997 from University of Mysore, Mysore. He is presently working as Professor in Department of Electrical and Electronics Engineering and Controller of Examinations at The National Institute of Engineering, Mysore, Karnataka, India. His research interest includes Reactive Power Optimization, Voltage Stability, Distribution Automation and AI applications to Power Systems.

Mr. H. Pradeepa obtained his B.E (Electrical) degree from University Visvesvaraya College of Engineering (UVCE) in 2002, M.Tech degree in Power System from NITK, Suratkal . His research interest includes Reactive Power Optimization, Voltage Stability, Distribution Automation and AI applications to Power Systems.

Likith Kumar. M. V. received the B.E. degree in Electrical & Electronics Engineering in 2011 from SKIT, Bangalore. He is presently pursuing research work at Department of Electrical and Electronics Engineering, The National Institute of Engineering, Mysore, Karnataka, India. His research interest includes Smart Grid, Communication System, Renewable Energy.

Maruthi Prasanna. H. A. received the Diploma in Electrical & Electronics Engineering in 2004 from D.R.R.Government Polytechnic, Davanagere and B.E. degree in Electrical & Electronics Engineering in 2011 from B.M.S.Evening College of Engineering, Bangalore. He is presently pursuing research work at Department of Electrical and Electronics Engineering, The National Institute of Engineering, Mysore, Karnataka, India. His research interest includes Distribution System Optimisation, Power System Stability studies, A.I. applications to power system and Smart Grid.

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Veeresha. A. G. received the B.E. degree in Electrical & Electronics Engineering in 2003 from SJMIT, Chitraduraga. He is presently pursuing research work at Department of Electrical and Electronics Engineering, The National Institute of Engineering, Mysore, Karnataka, India. His research interest includes Wind Energy, Distribution System Design, Distributed Generation.

Pradeep. N obtained his B.E (Electrical & Electronics) degree from SIET, Tumkur, India in 2010 and M.Tech in Power System from NIE, Mysore. His research interest includes Wind Energy Systems, Distribution system Automation, Computer Applications to Power System, Distributed Generation, Renewable Energy Sources, Transformers, and Transmission and Distribution.

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