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Computer based performance analysis of microprecessor based numerical distance relay
(UMT.Lahore, 2008) Muhammad Aizaz Farid
The analysis of unbalanced power systems depends usually on transformation methods by which the phase quantities are substituted by, for example, symmetrical component quantities. This research work proposes a methodology for the safety of a long distance transmission line of ultra-high voltage UHV using microprocessor for fault detection, isolation and auto-reclosing processes. Different protection schemes and protective relays can isolate or eliminate the fault that can cause hazard because they can detect faults in advance as compared to classical traditional devices. The algorithm inside the relay plays a vital role in fault detection and fast isolation of the faulty circuit. Although the numerical or digital relays are more advanced as compared to old electromechanical relays yet in order to study the suitability of a relay for a particular system, comparative study of operating algorithms, fault records, oscillography, fault locator and communication interface of different distance relays is required for selection of the right relay for fast and reliable operation of the protection system and fast isolation of the faulty circuit. Quick response of the relay for isolation of the fault plays a vital role in a country’s economy and revenue because long outages due to indiscriminate tripping, machines are tripped that require cold start which result in delay for the dispatch of energy (kWh) to the system. The present work will help in selecting the appropriate microprocessor based numerical distance relay for installation and commissioning at both ends of the protected transmission line.
Computer based performance analysis of microprecessor based numerical distance relay
(UMT.Lahore, 2008) Muhammad Aizaz Farid
The analysis of unbalanced power systems depends usually on transformation methods by which the phase quantities are substituted by, for example, symmetrical component quantities. This research work proposes a methodology for the safety of a long distance transmission line of ultra-high voltage UHV using microprocessor for fault detection, isolation and auto-reclosing processes. Different protection schemes and protective relays can isolate or eliminate the fault that can cause hazard because they can detect faults in advance as compared to classical traditional devices. The algorithm inside the relay plays a vital role in fault detection and fast isolation of the faulty circuit. Although the numerical or digital relays are more advanced as compared to old electromechanical relays yet in order to study the suitability of a relay for a particular system, comparative study of operating algorithms, fault records, oscillography, fault locator and communication interface of different distance relays is required for selection of the right relay for fast and reliable operation of the protection system and fast isolation of the faulty circuit. Quick response of the relay for isolation of the fault plays a vital role in a country’s economy and revenue because long outages due to indiscriminate tripping, machines are tripped that require cold start which result in delay for the dispatch of energy (kWh) to the system. The present work will help in selecting the appropriate microprocessor based numerical distance relay for installation and commissioning at both ends of the protected transmission line.
Neural network based optimal placement of base stations
(UMT.Lahore, 2010) Waqas Tariq Toor
Neural network has been used as an optimization tool in the past to solve various problems. In this research work, it is used to solve the problem of placing base stations in a given area in optimal way. Wireless communication has a great impact on our daily life and requires its working parameters to be optimum. These parameters include coverage area, hand off rates, number of calls per cell etc. All these and other parameters need to be optimally designed for a communication system to work optimally. Coverage area and interference are the two main parameters that are affected by the placement of base stations. If the base stations are placed very far from each other beyond their covering ranges, lot of spaces will be left with no coverage. On the other hand if they are placed very close to each other, interference will be the result. So the base stations need to be placed in optimum way. Placing the base stations requires work force which performs drive test to decide whether to place base station in a particular region or not. With our solution it only requires a computer to find the optimum placement of base stations. Given an area, our proposed methodology places the base stations in optimum way in that area. Neural network is used as a tool to find the solution to this problem.
Optimization of n+1 queens problem using neural networks and ‘the proximity rule of initialization’
(UMT.Lahore, 2010) Muhammad Waqas
The neural networks proved very handy in order to solve combinatorial optimization problems for the last two decades. Especially the Hopfield-Tank neural network model is extensively applied to obtaining an optimal/feasible solution to many different NP combinatory optimization problems like travelling salesman problem (TSP) and NP-hard combinatory optimization problem like N Queens Problem. This thesis describes a neural network optimizer/scheduler that optimizes a solution for a highly complicated version of N Queens Problem, i.e. N+1 non-threatening Queens on a N*N chessboard with an intermediate pawn on it. The behavior of the network is evaluated using asynchronous as well as synchronous mode of updating the neurons. Theoretical soundness of the network is established with simulation. Simulations show that the proposed neural network is capable of finding the optimized solution and is convergent to the global minima in 90% of the trials with polynomial average computational complexity.
Efficient detection schemes for cooperative spectrum sensing in fading channels using cognitive radio networks
(UMT.Lahore, 2010) Sadia Murshad
Advancements in wireless technologies are a breakthrough in revolutionizing the communication paradigm by providing ubiquitous internetwork access to large number of users at incredibly high data rates. The ever increasing deployment of mobile applications, networks and diverse services are a true depiction to this fact. As this trend continues the phenomenon of frequency spectrum occupancy is mounting up leading to spectrum scarcity. Analysis shows that for most periods the spectrum in control of majority primary users remains vacant and underutilized. This eventually implied to the idea of Dynamic spectrum allocation to users by Federal Communication Commission (FCC) which worked as a preventive measure against the issue of spectrum scarcity and underutilization. Cognitive Radios are sophisticated devices which can effectively sense the availability of frequency bands and can self modulate its parameters for dynamic transmission. In this thesis we have focused on Primary transmission detection techniques for spectrum sensing. Comprehensive analysis of energy detection, matched filter detection and cyclostationary feature detection is done with prime emphasis on their advantages and limitations. Based on these results we have proposed a two-step detection scheme which outperforms the existing models in terms of detection probability even at very low SNR value. The censoring capability of this detector leads to energy efficiency in cooperative environment. Analysis is done on Nakagami channel model for wireless communication which includes fading and multipath propagation effects. The system model discussed provides good agility for band shifting in case of interference or primary user presence because of reasonable sensing time which is very close to that of cyclostationary feature detector and can differentiate between desired signal and wideband noise.
Microcomputer based methodology for distance protection on long uhv transmission lines using symmetrical components
(UMT.Lahore, 2010) Mashood Nasir
This research work proposes a methodology for the long UHV transmission lines distance protection using microprocessor for fault detection, isolation and auto reclosing processes. For the protection of transmission lines distance relays are used, which depend on a function of impedance between relay location and fault point. In the present era, the development of microprocessors, their extra efficient controlling and computing abilities can be utilized in distance relaying for efficient computing of fault distance on transmission line and the type of fault occurred. The approach that is adopted here is to use sequence components to calculate the distance of fault point. In a normal distance relaying system that uses phasor values of voltage and current as input, six impedance calculating units are required for all ten types of fault that may occur in transmission line. With the advent of symmetrical component analysis tool these six impedance calculating units can be replaced by a single unit which will overall result in a considerable optimized and efficient protection system. Using Symmetrical component theory a single performance equation is developed that will encounter all type of faults on transmission lines. Microprocessor will serve the purpose of computing sequence components, distance of the fault from the relay point and the type of fault. The phasor values of voltage and current is given as an input to the microcomputer that will calculate symmetrical components and resulting sequence impedances. It eventually finds the distance of the fault using performance equation, ratios of voltages in that particular equation and their resulting phase difference. These calculations will lead us to the judgment of the phases involved in fault. ETAP is used for simulation to obtain desired results. Although the formulation described here is independent of hardware yet it provides a complete analytical base for distance protection and is analyzed for different types of fault conditions using simulation tools.
Bandwidth and subscriber estimation in uplink and downlink for multi class single cell users in mobile wimax
(UMT.Lahore, 2011) UMAIR SHAHID
The fundamentals required for steady growth of broadband wireless remain constant. According to the Ericsson’s official predictions, the global market of broadband connectivity will be around 320 million users by the end of this decade. The issues related with increased Deployment of WiMAX gives rise to issues related to QoS and Scalability. A unique methodology has been adopted to maximize the number of users per sector for multi-traffic users which include both Residential class as well as the Business class. The approach makes use of the Useful Bandwidth Estimations and implements an algorithm to provide a solution to QoS byrestricting the number of users according to Bandwidth allocated in both Uplink and Downlink directions. A modernize methodology to compute the system’s actual throughput and a traffic model for diverse application users are proposed with a step by step depiction to derive an algorithm to determine the maximum number of subscribers that each specific Mobile WiMAX sector may support. The results are shown using Matlab which intakes various system parameters along with Service class parameters and show the results in terms of the maximum number of users supported along with UL and DL bandwidth demanded and capacity available. The presented methodology would help those operators that plan to implement a wide coverage network in a city. Using the presented methodology, service providers will be in a position to estimate the exact number of base stations and hence the network investment and profitability.
Process analysis and feasibility study on using biodiesel for electricity generation
(UMT.Lahore, 2011) Mehwish Mujahid
The University has on-campus unutilized nearly twenty eight gallons of waste cooking oil that could be used more efficiently as biofuel. The waste cooking oil could turn into something that is economically efficient helping University power their generators and also be used as an educational asset to the University. If efficiently used, the waste cooking oil could become multifaceted in that it will benefit the University.The primary focus is to design a system in which the waste vegetables can be converted into Biodiesel .It is intended that this Biodiesel produced may ultimately be a fuel source for thepower generation from the generators.The procedure includes survey of electricity and diesel cost, preparation of biodiesel from fresh and waste vegetable oil, analysis of biodiesel , comparison of cost and energy efficiency by running generators.
Efficient shortest path routing in computer communication networks using neural network and heuristic algorithm
(UMT.Lahore, 2011) Farah Sarwar
Computer Networks are a breakthrough in current communication technologies providing an always-on and ubiquitous connectivity to virtually millions of users with the score still mounting up. This increased usage strongly requires enhancement in network infrastructure and improvements in management to facilitate users with better quality services. As the rate of users, who are transmitting data through a network link, increases the quality of service has to be compromised if not improved. Routing, which is a major aspect of this domain, has significant impact on the effectiveness of Communication Systems. Enhanced technologies should be introduced to let the system assist problems in a better way, preventing data loss and degradation in quality. Efficient routing algorithm should strive for the most appropriate and shortest path to route data through a network. Prior information of routers and data links, which helps to create paths, is required in almost every technique. A search algorithm, exploiting the properties of mathematical routing algorithm as well as of heuristics, can compute shortest path between given pair of routers more efficiently. On the other hand artificial intelligence can be very helpful in this domain. Artificial Neural networks, a domain of artificial intelligence, have found their way in engineering as well as Medical Sciences. The particular adaptive ability of neural networks for dynamic situations becomes a strongest feature which renders it best suitable for dynamic systems. John Hopfield used this feature and found their application in NP-complete optimization problems. Therefore, neural networks similar to Hopfield’s can also help to enhance shortest path computational techniques in routing. A* search algorithm and neural network are used to find shortest routes for unicast routing problems. Computer simulations are used to analyze and compare the results for different network sizes. A* search algorithm outperforms the neural network so far; however, limitations of neural networks are discussed.
Digital data scrambler using pic 18f452 microcontroller
(UMT.Lahore, 2012) Akbare Yaqub
With the invention of electronic ICs came the ease and simplicity with which we can design and test numerous ideas. The last few decades of the 20th century have seen many advances in the field of cryptography to improve the security of the transmitted data efficiently. Numerous ideas and algorithms have been devised and tested for the security of data transmission but the scheme presented in this thesis is very simple and easy to implement in hardware and yet it is very secure and reliable.A digital speech/data scrambler using PIC 18F452 Microcontroller is studied, designed and developed. The main theme of my Thesis “Digital Speech/Data Scrambling” is that a piece of data information is scrambled using pseudo random numbers and is transmitted. On the receiving end it can be descrambled with the help of the same pseudo random numbers which are generated at the receiving end in synchronism with the transmitted numbers to extract the original data. Although on the face of it, it seems very simple but in real world synchronization of the transmitter and the receiver and synchronously producing the same sequence of numbers at the both ends requires some special effort which is explained in this thesis in due course of time.Mathematically:If “DS” is the original digital data, and NT is the pseudo random number, then the scrambled output data So will be:So = Ds NT The transmitted scrambled data which is also received at the input of the receiver.Ds NT NR = DS The original unscrambled data because NT = NR.The unscrambling process seems very simple and it is indeed so but its practical implementation requires some special efforts which will become obvious as the progress is made in this thesis.The heart and soul of this thesis is the generation of NT, which is the pseudo random numbers at the transmitting and the receiving ends and synchronization between these numbers. Out of numerous methods available for the generation of NT, a simple and easy-to-implement technique in hardware has been developed and adopted in this thesis so as to enable implementation of the hardware feasible. This technique is explained in detail in the Chapters to follow of the thesis. Chapter 3 deals with the hardware details of the microcontroller and Chapter 3 explains software requirements of the microcontroller. Chapter 4 deals with the interrupt system of the microcontroller and the basic principles of serial communication are outlines in Chapter5. The complete program (code) is given in Chapter 6 with requisite explanation. The conclusions are drawn in Chapter 7.
Reduction of neural network memories interconnections
(UMT.Lahore, 2013) Warda Hussain
This research work proposes a detailed methodology for the reductions of interconnections of neural associative memories using Very Large Scale Integration. For data storage, various techniques have been employed in the past few decades and several improvements have been made regarding size, speed and capacity of memory. Content Addressable Memory (CAM) is a special type of memory which is relatively faster as compared to other memory techniques because the data is retrieved on the basis of partial information instead of using separate address bits. Using Hopfield neurobiological model, a computationally fast and inexpensive associative memory model is proposed. The proposed model is implemented with the reduced input vector length in VLSI that results in the sufficient reduction of the number of neurons to be integrated on a chip. By reducing the input vector length, the number of interconnections is reduced in CAM, consequently the order of multiplications during the formation of trans-conductance matrix is decreased that eventually leads towards a functionally compact and cost efficient CAM design. The proposed methodology is implemented on MATLAB/Simulink. The simulation results verify that the CAM designed using reduced vector length based neural associative memory model is highly efficient with respect to time, space and cost. Although the formulation described here, is independent of hardware yet it provides a complete analytical base for compact, efficient and inexpensive CAM design using simulation tools.
Transformer less design of polymer exchange membrane fuel cell based uninnteruptable power supply
(UMT.Lahore, 2013) Syed Mohsin Ali
This research work presents a transformer less model of fuel cell powered uninterruptable power supply (UPS). The design consideration of this research includes the utilization of Polymer Exchange Membrane Fuel Cell (PEMFC) market available stack model and designing of an efficient, low loss, cheap and high power design of a transformer less inverter model for 6kW UPS. This model is controlled with the help of embedded controller which ensures ripple and glitch free voltage regulated inverter providing pure sine wave as an output. This efficient inverter uses high frequency ferrite core transformer which would have a very small size and high efficiency. This model also ensures a very low total harmonic distortion. The proposed model utilizes a super capacitor module to overcome the electric transient conditions for the instantaneous power fluctuation, slow dynamics of the fuel cell and idealizing the overload response. Finally with synchronization techniques this UPS is connected to AC supply mains, also the calculations of fuel required for one hour continuous operation of 6kW UPS is formulated. The model proposed in this research work is implemented in MATLAB – SIMULINK environment.
Equivalent model development and grid integration of a solid oxide fuel cell
(UMT.Lahore, 2013) Muhammad Salik
The research work reported in this thesis is based on mathematical modeling of solid oxide fuel cell (SOFC) and its integration with grid. With the recent advancements in electrochemistry and the increasing demands for environment friendly energy resources, fuel cell technology has gained the major significance due to its compact size, low chemical emissions and low maintenance. Among different types of fuel cells, high temperature SOFC’s are capable for the stand alone high power production and grid-tied applications. Also the increase in demand for electric power, the distributed generation (DG) has attained much attention. DG utilizes alternate energy resources such as photovoltaic systems, wind energy systems and fuel cells. SOFC has proved to be a promising technology for distributed power generation with compact size, high power efficiency and absence of moving parts. SOFC is used as a reliable energy source in case of steady operations, but it shows slow response in case of transient conditions. Researchers have been working from past few years on modeling of SOFC to visualize its behavior under certain conditions. Most of the research articles do not include the detail of losses in SOFC which must be included in the equivalent model for analyzing the actual behavior of the SOFC over the time. In this research work, a mathematical model for a SOFC accounting for thermodynamic limits, effect of temperature and pressure variations is formulated to evaluate and visualize its actual characteristics. Activation, ohmic and mass transport over potentials are also included in the model. For connection of SOFC with grid, an intermediate module (Power Conditioning Unit) is proposed. Power Conditioning Unit (PCU) improves the slow response of SOFC and also steps up the DC voltages. It consists of a boost converter and a 3-phase inverter. PCU sets technical challenges in order to integrate SOFC with the utility grid. The overall modeling and integration of SOFC with the utility grid covers, the detailed representations of equivalent model of SOFC, power electronic modules, transformers and the grid integration technique. The proposed model is implemented in MATLAB-SIMULINK. It can be utilized for visualization of optimum characteristics and operation of grid integrated SOFC stack and its behavior under various operating conditions.
High speed content addressable memory with reduced size and less power consumption
(UMT.Lahore, 2015) HAMMAD RIAZ
Content Addressable Memory is a data storage device that is widely used in many applications. It is especially used in those applications needing fast memory access. However, due to use of parallel based search approach and frequent charge and discharge of Match lines and Bit lines/ search lines, the power consumption of CAM is considerable. This thesis presents an idea for reduction in power consumption of Ternary Content Addressable Memory over the chip. TCAM design techniques at the architectural level are reviewed and optimized solutions are provided. The size of CAM cell is further reduced with optimized speed and less power consumption. Some new types of ternary content addressable memory (TCAM) cells are proposed that can be utilized as per needs and requirements of the designers.
Performance evaluation of 802.11g using opnet
(UMT.Lahore, 2015) Hassan Tariq
Wireless networks in comparison with wired networks have main constraint of very limited bandwidth, but in spite of bandwidth constraint, due to mobility, flexibility and very cheap physical medium, i.e. air, wireless networks are becoming popular day by day. Wireless networks based on IEEE 802.11 standard are becoming very important and popular in current business era and are in high demand by the business companies. This work provides the performance evaluation of a number of technologies i.e. Direct Sequence Spread Spectrum, Frequency Hopping, Infra-Red, IEEE 802.11a and IEEE 802.11g based on delay and media access delay employing OPNET. The literature review has revealed that most of the work on this area has been done using other simulators like OMNET, Network Simulator 2, and Network Simulator 3 etc. However, not much work exists which has employed OPNET to carry out comparative evaluation employing delay and media access delay. For performance modeling and evaluation of telecommunication and computer networks, computer simulation is becoming admirable among computer network researchers. This huge popularity of computer simulation is due to the availability of various powerful and sophisticated simulators, and is also due to the built-in flexibility in validation offered by simulation and model construction. Various open and commercial network simulators are available for performance evaluation and modeling of telecommunication/computer networks. OPNET is a popular and famous network simulator that is available for this purpose, especially its subset, OPNET IT Guru. This thesis aims at utilizing of OPNET towards performance modeling and simulation of IEEE 802.11 wireless local area networks. The performance of IEEE 802.11g is modelled and evaluated in comparison with other technologies such as Direct Sequence Spread Spectrum, Frequency Hopping, Infra-Red and IEEE 802.11a. The techniques useful in reducing end-to-end delay and media-access delay at all available data rates are discussed for future work.
Comparative analysis of eigenstructure assignment and root locus techniques over flight control system
(UMT.Lahore, 2015) Usman Inayat
This research work presents a comparative analysis of eigenstructure assignment and root locus technique. The consideration of this research are to design a controller that control a linear time invariant system (LTI) efficiently. The design is done by classical approach of dividing the controller into, a longitudinal control segment and a lateral control segment. Controller ensure that the response time of the system must be minimum and robust. Gain matrix for the controller is calculated by eigenstructure assignment technique. In the purposed eigenstructure assignment technique decoupling is done between modes. The eigenstructure assignment technique is implemented on an aircraft model and also the response time, settling time gain and phase margins are calculated. Finally the results are compared the conventional root locus technique for the control system design for linear time invariant systems (LTI). The model proposed in this research work is implemented in MATLAB – SIMULINK environment.
Determination of symmetrical components of power network using microprocessor based digital filter
(UMT, Lahore, 2015) BILAWAL REHMAN
This research work proposes a novel technique to determine the magnitude of symmetrical components. In the present era, development of microprocessors and their extra efficient controlling plus computing abilities can be utilized to develop a digital protection system. Method of least squares is adopted here to estimate magnitude of symmetrical components under all field conditions. Symmetrical components have been found an effective tool for the analysis of symmetrical and unsymmetrical faults in power system. Moreover, magnitude of symmetrical components are also used as a caution about faults in system. The proposed algorithm, that determines symmetrical components, has less complexity and execution time. The phasor values of voltage is given as an input to the microcomputer that will calculate symmetrical components by applying proposed methodology. Instead of eomputing symmetrieal components again and again for every incoming sample, microprocessor will add impact of every new sample of voltage to the previous estimated values by deploying the proposed technique. This makes the technique unique and simple to implement in microprocessor based digital protection system. These calculations will lead us to the fault occurred in power system. Although the formulation described here is independent of hardware yet it provides a complete analytical base for protection system and is analyzed for different types of fault conditions using simulation tools.
Cost-efficient design and implementation of weather base station and satellite communication system
(UMT.Lahore, 2015) Salman Mahmood
National Oceanic and Atmospheric Administration has group of artificial satellites orbiting Earth. Such satellites are benefiting humanity for 6 decades by transmitting data related to weather and climate. By processing such data researchers can predict weather situations and climate related disasters .Receiving data of such satellites is very costly process. In first phase of this research a cost efficient system for receiving and decoding data from the weather satellite NOAA 18 was designed and implemented, in order to establish a weather ground station first of its kind in the region. A special purpose Quadrifilar Helicoidal Antenna and Trifilar Balun were designed and implemented to improve the signal strength at location of project i.e. Lahore. Realtek Software Defined Radio was used as RF receiver which was integrated with Raspberry Pi 2 .The combination of QHA, Trifilar Balun, RTL SDR and Raspberry Pi 2 proved a cost efficient setup for weather base station with fantastic results. The innovative setup was 38 times cheaper than previously implemented systems. In second phase of this research the cost efficient construction of SDR based satellite commutation system was created. In which ground and space segments were developed. Raspberry Pi 2 was programmed with the help of python and C to work as a Software Defined Radio. It’s General Purpose Input Output Pin 4 and Pin 18 were used for transmitting audio, text and image (video) over five modulation schemes which were FM, SSB, VFO, FSK and SSTV at flexible range of 50 MHz to 750 MHz .Attachment of RTL SDR with Raspberry Pi 2 made it to receive and decode RF signals within the range of 24Mhz to 1.8GHz. The improvisational marvel of Raspberry Pi 2 as transceiver proved perfect replacement for costly transceiving systems such as Universal Software Radio Peripherals and HAM Radios. This setup proved to be 30 times cheaper than previously used communication systems and perfect to be considered as communication system for any student satellite project.
Space based solar power generation using a distributed network of satellite
(UMT.Lahore, 2015) ZUNAIRA NAZEER AHMED
Space Based Solar Power generation proposed a new technique to fulfill the increasing energy demand .It has high efficiency as compared to the earth based solar power generation. In this technique we will established satellite constellation at the geo synchrouns earth orbit (GEO) .At this constellation solar panel assembly is attached which capture energy from the sun at GEO solar energy will not face any hindrance as in earth based solar power generation(EBSP) for instance in EBSP maximum energy will not reach to the earth due to atmospheric attenuation , weather condition .Moreover in SBSP it will not face any such type of hurdle and at GEO 30% maximum solar energy is present .When solar energy captured by the satellite constellation it will transmitted to the earth with the help of WPT technique . In this thesis mainly concentrate on the (i) Satellite constellation architecture (ii) Power Transmission technique through space (iii) Device which used to transmit this power .In previous SBSP approach power is transmitted through the Laser transmission technique .But in this thesis we are using Wireless Power Transmission (WPT) technique to send microwave power to the earth. Research on the best material for solar panel which has maximum conversion efficiency, Research on different alternatives of SPS (Solar Power Satellite), research on different type of transmission antenna has been done in this thesis. When all the DC energy is converted to the microwave power this must be transmitted to the earth at “Rectenna” assembly and at Rectenna it is again converted to the Dc form .Rectenna assembly consist of rectifying circuit plus antenna plus filter .In this research we develop best rectifier circuit , and efficient low pass filter which improves the efficiency of Rectenna assembly .At the end all technical component of SBSP for instance sun synchrouns orbit ,satellite constellation , relative motion of satellite , space debris , device to convert DC to microwave power ,Transmission antenna , selection of ground track , and Rectenna component all these technical component are designed in MATLAB version (2013b) . And at the final results conclude in the table which shows that SBSP has more efficiency as compared to the EBSP.
Design and implementation of algorithm for protection of dg based electric power networks
(UMT.Lahore, 2015) HARIS SIRAJ
In this research work an intelligent and fault tolerant protection scheme for electric power networks considering the penetration of large scale distributed generation (DG) is presented. Electricity is required in nearly every field of the modern life. Thus a reliable and fault tolerant system is required for the generation, transmission and distribution of electric power. The earliest systems used to distribute electric power were radial in nature working on a single source and sink mechanism. However in modern era, the scheme of DGs are gaining wide importance because of their ability to include renewable and alternate energy resources as generation and thus producing a cleaner and greener energy. Usually protection of electric systems is carried out by using fuses. Fuses are not intelligent and their whole operation is defined by fault clearing time and min melting point. Relays on the other hand are intelligent and are employed to sense faults and trip CBs. When the scheme of the system changes from radial to distributed, the coordination of protection devices is lost and therefore, whole protection scheme may collapse. Also coordination is lost by adding more DG unit to the existing DG system as the values of fault current changes for relays. In the implemented scheme, the coordination between various protection devices will hold even after the addition or modification of a distributed generation unit. Load flow analysis and short circuit analysis is performed after each network modification and the results are fed to a master relay that coordinates with all the other relays in the power system. The proposed scheme is implemented using MATLAB and the results validate the optimal functioning of the proposed scheme. Thus, the successful implementation of proposed scheme ensures the reliable protection of the power network considering large scale distributed generation.

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