ACKNOWLEDGEMENTIt gives me immense pleasure to express deep sense of gratitude

Professor Sri.O.V.S SRINIVASA PRASAD, M.Tech. my guide, professor and HOD of the EEE department. for his whole hearted and individual guidance throughout the seminar and also for providing all the necessary facilities that led to the successful completion of my seminar With his sustained and sincere effort, this seminar would not have taken this shape. He encouraged and helped me to overcome various difficulties that I faced at various stages of my seminar.

I would like to take this opportunity to thank for our beloved Principal Dr.P. LAKSHMI NARAYANA,M.Tech, Ph.D for providing a great support for me in completing of this seminar.

I would like to thank all the faculty members of the department of Electrical & Electronics Engineering for their direct or indirect support for helping me in completion of this seminar.

Finally I would like to thank all of our friends and family members for their continuous help and encouragement.

S.KAVITHA

(12MA1D4306)

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ABSTRACTDistributed generation (DG) on the distribution system provides

many potential benefits like peak sharing, fuel switching, increased efficiency and improved environmental performance. DG can be used to generate a customer’s entire electricity supply. Impacts are steady state voltage rise, increase the fault level, power quality, islanding. Islanding is one of the major problems in distributed generation.

Islanding occurs when a portion of the distribution system becomes electrically isolated from the remainder of the power system yet continues to be energized by distributed generators. An important requirement to interconnect a DG to power distributed system is the capability of the DG to detect islanding detection. Failure to trip islanded generators can lead to a number of problems to the generators and the connected loads. The current industry practice is to disconnect all distributed generators immediately after the occurrence of islands. To achieve such a goal, each distributed generator must be equipped with an islanding detection device.

So many islanding detection techniques are available, each one having their own advantages and drawbacks. A fuzzy rule-based passive islanding detection technique is implemented is preferred. The initial classification model is developed using Decision Tree (DT) which is a crisp algorithm. This algorithm is transformed into a fuzzy rule base by developing fuzzy membership functions from the DT classification boundaries.

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LIST OF FIGURES Page No

FIG 1.1 : Islanding Formation Including Distributed Generator 2

FIG 2.1 : Scenario of Islanding Operation 6

FIG 3.1 : Islanding Detection Techniques 9

FIG 3.2 : DG power line Signaling Islanding Detection 10

FIG 3.3 : DG Multi Power Line Signaling Islanding Detection 11

FIG 3.4 : DG Transfer Trip Islanding Detection 13

FIG 3.5 : Phase response of DG and local load 18

FIG 4.1(a) : Binary decision tree 27

FIG 4.1(b) : The decomposed feature space 27

FIG 4.2 (a) : The classification problem and the approximating decision

boundary of a crisp rule-based system 29

FIG 4.2(b) : Membership functions of the fuzzy model that gives a

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perfect Classification 29

FIG 4.3 : Simplification of the fuzzy classifier 31

FIG 4.4 : Scheme of the complete DT identification approach 32

FIG 4.5 : Block diagram of power distribution network with DG 34

LIST OF ABBREVIATIONS

DG : DISTRIUTED GENERATION

DERs : DISTRIBUTED ENERGY RESOURCES

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