Top PDF Overcurrent relay setting by using adaptive technique

Overcurrent relay setting by using adaptive technique

Overcurrent relay setting by using adaptive technique

3.3 Case study: IEEE-14 Bus Test System 27 3.4 Proposed Adaptive Protection Algorithm 28 3.5 Operating Scenario for IEEE-14 Bus Power Grid 29 3.6 Thevenin Equivalent Circuit o f Power Grid 32 3.7 Distribution System and Overcurrent Protection Scheme 36

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Optimal Overcurrent Relay Coordination: A Review

Optimal Overcurrent Relay Coordination: A Review

Several methods have been proposed in the past four decades since 1960s for the coordination of overcurrent relays. These methods can be classified into three classes which are trial and error, topological analysis method and optimization method [9-13]. Trial and error approach was used but it has slow convergence rate as a result of large number of iterations needed to reach a suitable relay setting [8, 14]. To minimize the number of iterations required for the coordination process, a technique to break all the loops called breakpoint and locate the starting relays at these points is recommended. Finding the breakpoints is the significant part to initiate the coordination process. Topological methods which include functional and graph theory are used to determine break points [14]. The solution found using this method is the best of option settings considered but not optimal in any strict sense. Meaning that, the TSM or time dial settings (TDS) of the relays are high. Furthermore, due to the complexity of the system, trial and error approach and topological analysis are time consuming and not optimal.
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Adaptive mho distance relay for combined 
		transmission line: An optimization technique for charging current 
		compensation

Adaptive mho distance relay for combined transmission line: An optimization technique for charging current compensation

Power transmission system is protected with several relays to increase reliability. Underground cable is protected with differential relay, but the main protection device in overhead line is distance relay which is backup by an overcurrent relay. Moreover, distance relay is used to detect fault occurrence in transmission line and also to estimate fault location. Several studies were carried out to improve distance relay operation and fault location estimation to make distance relay adaptive with specific transmission system. On the other hand, mis-operation of protective devices will occur due to conventional transmission system analysis in lumped parameter. The well-known drawbacks of transmission line are fault resistance [1-4] and charging current [5-8] of transmission system. These two effects forced distance relay to mis- operate.
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Improvement of coordinated bidirectional overcurrent relay’s sensitivity and load restoration time using neuro-fuzzy technique in smart grid

Improvement of coordinated bidirectional overcurrent relay’s sensitivity and load restoration time using neuro-fuzzy technique in smart grid

Protection system for power system has prevailed developed to minimize the damage and to make sure supply in safe condition, continuously and economically. Relay is one of the most paramount components in protection system. There are several kinds of relay that each kind has own characteristic. A relay is device that makes a measurement as a supposititious succedaneum receives a signal that causes it to operate and to affect the operation of other equipment. It responds abnormal conditions in faulty section of the system with the minimum interruption of supply. Protection of distribution networks is one of the most paramount issues in power systems. Overcurrent relay is one of the most commonly used protective relays in these systems. There are two types of settings for these kinds of relays: current and time settings. A opportune relay setting plays a crucial role in reducing undesired effects of faults on the power systems. Overcurrent relays commonly have plug setting (PS) ranging from 50 to 200% in steps of 25%. The PS shows the current setting of the overcurrent relays. For a relay installed on a line, PS is defined by two parameters: the minimum fault current and the maximum load current. However, the most paramount variable in the optimal coordination of overcurrent relays is the juncture multiplier setting (TMS). The proposed work is on bi-directionally communicated directional overcurrent relay protection scheme for perspicacious grid which is supplied by multiple renewable sources under islanded mode. Antecedent work has prevailed gone in protection coordination based on the bi- directional relay utilizing Neuro-Fuzzy control technique. As still there is a possibility to improve the relay‟s sensitivity and further reduction of load restoration time can be done from the previous control techniques. The scheme is tested on IEEE 9 bus system equipped with the sundry renewable generation units as well as distribution generation units. To achieve the desired relay sensitivity and load restoration time the neuro -fuzzy control techniques will be used and opportune bi-directional communication is maintained within the relay pairs. So that the power system protection and stability can be improved further. Simultaneously the lifespan of the protective relay can be improved by the prevention of false tripping. Simulations are verified by using of MATLAB/Simulink.
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Improvement of Coordinated Bidirectional Overcurrent Relay’s Sensitivity and Load Restoration Time Using Fuzzy Technique in Smart Grid

Improvement of Coordinated Bidirectional Overcurrent Relay’s Sensitivity and Load Restoration Time Using Fuzzy Technique in Smart Grid

ABSTRACT: Protection system for power system has prevailed developed to minimize the damage and to make sure supply in safe condition, continuously and economically. Relay is one of the most paramount components in protection system. There is several kind of relay that each kind has own characteristic. A relay is device that makes a measurement as a supposititious succedaneum receives a signal that causes it to operate and to effect the operation of other equipment. It responds abnormal conditions in faulty section of the system with the minimum interruption of supply. Protection of distribution networks is one of the most paramount issues in power systems. Overcurrent relay is one of the most commonly used protective relays in these systems. There are two types of settings for these kinds of relays: current and juncture settings. A opportune relay setting plays a crucial role in reducing undesired effects of faults on the power systems. Overcurrent relays commonly have plug setting (PS) ranging from 50 to 200% in steps of 25%. The PS shows the current setting of the overcurrent relays. For a relay installed on a line, PS is defined by two parameters: the minimum fault current and the maximum load current. However, the most paramount variable in the optimal coordination of overcurrent relays is the juncture multiplier setting (TMS). The proposed work is on bi- directionally communicated directional overcurrent relay protection scheme for perspicacious grid which is supplied by multiple renewable sources under islanded mode. Antecedent work has prevailed gone in protection coordination based on the bi-directional relay utilizing sundry algorithms. Still there is a possibility to improve the relay’s sensitivity and further reduction of load restoration juncture can be done. The scheme is tested on IEEE 9 bus system equipped with the sundry renewable generation units as well as distribution generation units. To achieve the desired relay sensitivity and load restoration juncture the fuzzy control techniques will be used and opportune bi-directional communication is maintained within the relay pairs. So that the power system protection and stability can be improved further.
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A New Adaptive Technique for Enhancement of Zone 2 Settings of Distance Relay

A New Adaptive Technique for Enhancement of Zone 2 Settings of Distance Relay

This method is primarily similar to the non-adaptive method except that impedances need not be calculated for maximum and minimum levels of generation and no contingencies need to be considered. The seen imped- ances are calculated for the existing conditions. This means that the setting for zone-2 element of distance relay in adaptive protection system is determined by cal- culating the apparent impedance seen by zone-2 relays when faults are simulated on the lines emanating from the remote bus considering the prevailing operating con- ditions of the power system. The adaptive setting method for zone-2 relays is described with reference to the sys- tem of Figure 3 and consists of the following steps for determining the zone-2 setting of the relay R BK [11].
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Adaptive relay techniques for OFDM-based cooperative communication systems

Adaptive relay techniques for OFDM-based cooperative communication systems

The main goal of resource allocation for multihop relay systems is to maximize the end- to-end channel capacity or minimize the resource consumption by adaptively allocating the transmission resources, including time slots, frequency bandwidth and power consumption. In order to improve the system performance, many resource allocation schemes have been inves- tigated in the literature, for the different scenarios of the relay networks [99, 101, 157–166]. However, the allocation schemes in previous work only aim to maximize the total end-to-end channel capacity, which implies the assumption that the traffic loads from the source to the destination and from the destination to the source are the same. However, this assumption is not practical at all. For different application, the traffic loads of down-link and up-link are asymmetric in most practical systems. For instance, the web browsing and online video ser- vice have dominant traffic volume in downlink direction [167–169]. The results of measured traffic statistics also shows that the traffic of down-link and up-link is significantly different in most practical cases [23–25]. Therefore, in two-way systems, the resource allocation algorithm without considering the asymmetric traffic loads leads to the fairness issue. Simply maximiz- ing the total end-to-end capacity will result in the lopsided allocation of the resource, i.e., light traffic flows would obtain relatively excessive resource. On the other hand, forcing the two terminals with different traffic loads achieve the same capacity only according to the channel condition causes a problem such that the heavy traffic flows is deprived of resources and suffers low data rate. Meanwhile, the allocation scheme to achieve the equal capacity of two terminals does not take into account the notion that the two terminals might have different data rate re- quirements, eg., in the systems with service level differentiation or flexible billing mechanisms for different classes of users. Therefore, ignoring the asymmetric traffic in resource allocation lowers the overall quality of service of the relay network. For the bidirectional asymmetric traffic scenario, the traffic-load ratio between the two terminals should also be one of the factor to determine the resource allocation algorithm.
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A Relay Prevention Technique for Near Field Communication

A Relay Prevention Technique for Near Field Communication

These solutions are robust for the tags tested, all Mifare Ultralight A, and con- sistent in behavior. A worst case example for the Android system would include the occasional false positive which is a much better solution then an occasional false neg- ative. This system can be built into existing readers and secondary authentication could be requested in more secure applications. This would not prevent tags com- munication which took more time, but would add a level of security to misbehaving tags. If applications were less secure, or a decision was made that a relay attack was unlikely or unimportant to the application the feature could just be ignored or turned off. This approach fits into the RFID/NFC standard with a minimal impact to existing technology. It causes absolutely no changes to all the tags out now and being produced in the future.
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To Reduce the Packet Collision by Using Adaptive Technique in WSN

To Reduce the Packet Collision by Using Adaptive Technique in WSN

A wireless sensor network consists of a large number of nodes spread over a specific area where we want to look after at the changes going on there [3]. A sensor node generally consists of sensors, actuators, memory, a processor and they do have communication ability. All the sensor nodes are allowed to communicate through a wireless medium. The wireless medium may either of radio frequencies, infrared or any other medium, of course, having no wired connection. These nodes are deployed in a random fashion and they can communicate among themselves to make an ad-hoc network. If the node is not able to communicate with other through direct link, i.e. they are out of coverage area of each other; the data can be sending to the other node by using the nodes in between them. This property is referred as multi-hoping [4]. All sensor nodes work cooperatively to serve the requests. Generally WSNs are not centralized one as there is peer-to-peer communication between the nodes. So there is no requirement of prior established infrastructure to deploy the network [5]. WSN gives flexibility of adding nodes and removing the nodes as required. But this gives rise to many drastic changes to deal with in the network topology such as updating the path, or the network tree, etc.
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A NOVEL TECHNIQUE FOR IMAGE RESTORATION USING ADAPTIVE FILTERS

A NOVEL TECHNIQUE FOR IMAGE RESTORATION USING ADAPTIVE FILTERS

A Test image is taken and it is subjected to point spread function to degrade the image .after wards the adaptive linear filters applied to degraded image to get the restored image .To evaluate the fidelity criteria NCC and PSNR &ISNR is computed. In this computation the regression analysis will give a better idea which method is better one to calculate the efficiency of the algorithm.

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Relay Selection for Multiple Access Relay Channel Using JNCC

Relay Selection for Multiple Access Relay Channel Using JNCC

ABSTRACT: Wireless Relaying is a promising solution to overcome the channel impairments and provides high data rate and coverage for beyond 3G mobile communications. By using JNCC (Joint network channel coding) reliable transmission over an error- prone channel can be achieved. It seamlessly couples channel coding and network coding and can effectively combat the detrimental effect of fading its wireless channels. This paper presents a relay selection for JNCC, in which the source node simultaneously transmits their own information to N-number of relays as well as the destination node and best relay will be selected to forward the new version of information. Simulations have been performed to show that BER and FER for multiple access relay as a function of SNR and also SER and outage probability for JNCC. Moreover, the results show that joint network-channel coding with MARC outperforms the single relay.
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Wind Power Plants Protection Using Overcurrent Relays

Wind Power Plants Protection Using Overcurrent Relays

In power systems, all of these OCRs must be properly coordinated with each other in order to protect the power elements from the currents [8]. To do so, the vital settings of OCRs, which are the Plug Setting Multiplier (PSM) and the Time Setting Multiplier (TSM), must be set suitably. PSM is varied in the range of 50% to 200% and in steps of 25% [9]. This setting is only used for inverse current relays which detect phase to phase fault. For the relays that detect phase to ground fault, the PSM is quite different. It is varied in in the range of 10% to 40% in steps of 10%, or in the range of 20% to 80% in steps of 20%. The point that should be taken into consideration is that the more Plug Setting (PS) the relay has, the higher current the relay requires to trip. TSM ranges from 0 to 1 in steps of 0.1. However, sometimes it varies in steps of 0.05. The maximum TSM is 1 and the minimum is 0.05. In order to coordinate OCRs with each other, there is a time interval between a primary relay and a backup relay operation and this is called the Coordination Time Interval (CTI). This time interval is in the range of 0.3 and 0.5 seconds for conventional relays, while for numerical relays it is set at 0.2 seconds, which means they operate faster compared to conventional relays [10]. So in order to coordinate relays with each other, the relay operation time and CTI must be taken into consideration. After the characteristics of these relays are designated, then the coordination of OCRs can be properly undertaken [11].
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An Efficient Technique to Optimize the Energy in Wireless Sensor Networks Using Mobile Relay

An Efficient Technique to Optimize the Energy in Wireless Sensor Networks Using Mobile Relay

In third approach, the network consists of mobile relay nodes along with static base station and source node. Relay node do not transport data to the destination; instead, they move to different locations to decrease the transmission costs. We use the mobile relay approach in this work. An author named Goldenberg et al. [11] showed that in iterative mobility algorithm, each relay node which moves to the middle of its neighbor nodes converges on the best possible solution for a single routing path. In [12], mobile nodes decide to move only when moving is advantageous.
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African American interpreters in the video relay service setting

African American interpreters in the video relay service setting

In general, the work of a sign language interpreter can be very taxing on the body and even more taxing depending on the setting the interpreter works in. For example, K-12 interpreters work long hours and sometimes do not have a team to share the workload. Dean, Pollard, and Samar (2010) compared the conditions of interpreters working in three settings: VRS, K-12, and staff/community settings. They came to the conclusion that all three settings were fraught with physical exertion. Gretchen and Samar (2015) cited Fischer, Marshall, and Woodstock (2012) in their study saying one in every four sign language interpreters has experienced some form of musculoskeletal pain that has impeded their work abilities. In addition to the linguistic and technology challenges VIs face, VIs also experience emotional challenges that include having to process calls that may cause VIs to experience emotional roller coasters. VIs experience a wide range of emotions, which could range from highly elated conversations to depressive/traumatic conversations (Wessling & Shaw, 2014).
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Quadrotor Control using Adaptive Fuzzy PD Technique

Quadrotor Control using Adaptive Fuzzy PD Technique

time e.g. surveillance, inspection, search, rescue and reducing the human force in undesirable conditions. Quadrotor UAV is equipped with four rotors for the purpose of stability but this will make quadrotor more complex to model and control. In this paper, intelligent controller is designed to control attitude of quadrotor UAV. The paper presents a detailed simulation model for a Quadrotor UAV and Adaptive Fuzzy PD control strategy is designed to implemented for four basic motions; roll, pitch, yaw, and Z Height. The controller presented in this paper is very simple in structure and it is easy to implement. The main objective of this paper is to get the desired output with respect to the desired input. Simulink model and results are shown at the end of the paper
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Optimum Setting Strategy for WTGS by Using an Adaptive Neuro Fuzzy Inference System

Optimum Setting Strategy for WTGS by Using an Adaptive Neuro Fuzzy Inference System

In the practice, many anemometers have to be used to measure the wind speed which can derive the optimum setting values of rotor speed and generator power. And not only the single WTGS but also the wind field needs many anemometers to provide adequate information. However, due to the varied environment, the measure- ment may provide inaccurate signal to the system and the traditional optimum setting strategy may have some drift to the initial setting after a period of operation. Besides, the installation and maintenance of the anemometers in- crease the cost and reduce the reliability of the whole system.
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Detection and Localization of Heart Sound Using
          Adaptive Learning Technique

Detection and Localization of Heart Sound Using Adaptive Learning Technique

Abstract — In the field of artificial intelligence, adaptive learning technique refers to combinations of artificial neural networks. In this thesis the adaptive learning technique is been implemented to carry out the Detection and Localization of heart sound. It can be implemented in the NS2 and MATLAB In ns2 part logic will identify the sound of heart and in matlab part heart sound is detected. The issue of Detection and localization of heart sound source is discuss in this thesis in new algorithm for estimating heart location, based on adaptive learning technique introduced and describe.
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Flame and Fire Boundary Tracking Using Self Adaptive Technique

Flame and Fire Boundary Tracking Using Self Adaptive Technique

In general, a flame region has a stronger luminance in comparison to its ambient background and the boundary between the flame region and its background is mostly continuous in nature. Furthermore, in most of the cases, there is only a main flame in the image under consideration; otherwise, the image can be segmented so that each of the segmented area contains only one main flame. Accordingly, an auto-adaptive computing algorithm is proposed where these features are used to identify the flame edges. The basic strategy is to detect the coarse and superfluous edges in the flame image then identify the flames principal edges and remove irrelevant ones. The algorithm can be divided into following logical steps. A. Adjusting the gray level of the flame image.
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A Novel Technique for Speech Processing Using
Combinational Adaptive Methods

A Novel Technique for Speech Processing Using Combinational Adaptive Methods

Adaptive filters are successfully using in removal of artifacts presenting in ECG signal [1]. For processing and analysis of speech adaptive filtering techniques plays a vital role[2].If the level of the noise exceeds the dynamic range of electronic devices, the reference and error channels of active noise control systems may be saturated in real time applications.The performance of active noise control system which uses linear adaptive filter algorithm was degraded by the non-linear saturation[3].adaptive filters have been included in the syllabus of undergraduate digital signal processing (DSP) courses[4].The LMS algorithm are widely used in many applications as an effect of its simplicity and robustness [5]. LMS based adaptive filters used in all sparse systems for noise Cancellation [6].Adaptive LMS filters are employed in the design of mechanical,electronic systems [7] LMS Algorithm is widely used in a different variety of applications, in the area of speech enhancement and biomedical signal
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An adaptive relay node selection algorithm based on opportunity

An adaptive relay node selection algorithm based on opportunity

The research of classical cooperative relay communication technology has focused on the improvement of system per- formance, but takes no account of the energy efficiency of the system. At present, from an energy efficiency stance, the literature [2, 3] demonstrated that the energy consumption of the wireless communication network can be improved by cooperative diversity techniques. P. Rost used a fixed relay structure in the cellular communication which could reduce the energy consumption effectively and thus enhance sys- tem performance in case of increasing the density of the relay [4]. Nokleby and Aazhang used the game theory model to demonstrate that the transmission energy effi- ciency of two users could be improved under different channel conditions by a collaboration of two users [5]. But related researches above do not take into account the aver- age energy consumption of all nodes and selecting relay nodes adaptively based on opportunity, which thus extends the life cycle of the network.
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