Relay Function Research Articles

Intelligent Street Lighting: An IoT-based System for Adaptive Brightness and Fault Management

The research aims to develop an intelligent fault detection and control system for street lights using an STM32 microcontroller and Internet of Things (IoT) technologies. The system uses various sensors and communication methods to manage lighting more effectively and maintain infrastructure better. Light-Dependent Resistors (LDRs), which turn lights on automatically at nightfall and off at dawn, are essential to the system's operation. Moreover, motion is detected by the infrared (IR) sensors on the street, allowing the lighting to save energy by dimming during times of low traffic and brightening when movement is detected. By using control logic and sensor readings, a relay functions as an electronically controlled switch to turn the lights on and off. To process sensor data, the STM32 microcontroller is used in the main functionality. Energy savings are facilitated by the automated on/off switching based on ambient light levels, enabled by the LDR sensor data. In addition, the device includes a GPS module for precise street light location tracking. An IoT platform transmits this location data as well as operational status and real-time sensor readings. Maintenance staff can access regional data on light quality and sensor readings through an LCD display. This extensive data enables maintenance team to focus better, use resources efficiently, and enable remote monitoring and fault identification (e.g., burned-out bulbs). This Internet-of-Things (IoT) system provides an economical and environmentally friendly approach to efficient street light management by integrating automation, remote control, and real-time monitoring.

Robust distance protection for cross-country faults in power grids with high penetration of inverter- based resources

Cross-country faults can adversely affect the operation of protection devices. Relays whose pickup is based on overcurrent or impedance elements are more likely to fail during cross-country faults. The failure can be expressed as an unnecessary trip of all phases during a single-phase fault or even blocked relay functions. Relays may also fail to operate due to low fault currents, which is the case when power grids make use of many inverter-based resources (IBR) or when two simultaneous faults occur in the same phase and in different locations. This paper proposes a Recursive Discrete Stockwell Transform (RDST) method for addressing the mentioned challenges. The energy content computed by the RDST is used for fault detection and faulty phase selection. A robust distance relay model is proposed to ensure correct relay performance and is combined with a directional and an impedance trajectory module. The proposed method performance is thoroughly evaluated by applying real-time simulations for 6480 different cross-country faults, including three repetitions, four different generators (Synchronous generators, Wind turbine type-III, Wind turbine type-IV), two rating powers, three different fault distances, five different types of faults, and six grid codes. Ninety cases are also tested with real devices in hardware in the loop. Simulation results confirm the method's ability to detect different fault types, even during low fault currents, and to ensure high accuracy in phase selection.

Prefrontal Oscillatory Slowing in Early-Course Schizophrenia Is Associated With Worse Cognitive Performance and Negative Symptoms: A Transcranial Magnetic Stimulation-Electroencephalography Study

BackgroundAbnormalities in dorsolateral prefrontal cortex (DLPFC) oscillations are neurophysiological signatures of schizophrenia thought to underlie its cognitive deficits. Transcranial magnetic stimulation with electroencephalography (TMS-EEG) provides a measure of cortical oscillations unaffected by sensory relay functionality and/or patients’ level of engagement, which are important confounding factors in schizophrenia. Previous TMS–EEG work showed reduced fast, gamma-range oscillations and a slowing of the main DLPFC oscillatory frequency, or natural frequency, in chronic schizophrenia. However, it is unclear whether this DLPFC natural frequency slowing is present in early-course schizophrenia (EC-SCZ) and is associated with symptom severity and cognitive dysfunction. MethodsWe applied TMS–EEG to the left DLPFC in 30 individuals with EC-SCZ and 28 healthy control participants. Goal-directed working memory performance was assessed using the AX–Continuous Performance Task. The EEG frequency with the highest cumulative power at the stimulation site, or natural frequency, was extracted. We also calculated the local relative spectral power as the average power in each frequency band divided by the broadband power. ResultsCompared with the healthy control group, the EC-SCZ group had reduced DLPFC natural frequency (p = .0000002, Cohen’s d = −2.32) and higher DLPFC beta-range relative spectral power (p = .0003, Cohen’s d = 0.77). In the EC-SCZ group, the DLPFC natural frequency was inversely associated with negative symptoms. Across all participants, the beta band relative spectral power negatively correlated with AX–Continuous Performance Task performance. ConclusionsDLPFC oscillatory slowing is an early pathophysiological biomarker of schizophrenia that is associated with its symptom severity and cognitive impairments. Future work should assess whether noninvasive neurostimulation, including repetitive TMS, can ameliorate prefrontal oscillatory deficits and related clinical functions in patients with EC-SCZ.

A DRL-Based Satellite Service Allocation Method in LEO Satellite Networks

Satellite computing represents a recent computational paradigm in the development of low Earth orbit (LEO) satellites. It aims to augment the capabilities of LEO satellites beyond their current transparent relay functions by enabling real-time processing, thereby providing low-latency computational services to end users. In LEO constellations, a significant deployment of computationally capable satellites is orchestrated to offer enhanced computational resources. Challenges arise in the optimal allocation of terminal services to the most suitable satellite due to overlapping coverage among neighboring satellites, compounded by constraints on satellite energy and computational resources. The satellite service allocation (SSA) problem is recognized as NP-hard, yet assessing allocation methods through results allows for the application of deep reinforcement learning (DRL) to obtain improved solutions, partially addressing the SSA challenge. In this paper, we introduce a satellite computing capability model to quantify satellite computational resources. A DRL model is proposed to address service demands, computational resources, and resolve service allocation conflicts, strategically placing each service on appropriate servers. Through simulation experiments, numerical results demonstrate the superiority of our proposed method over baseline approaches in service allocation and satellite resource utilization, showcasing advancements in this field.

Definite time over-current protection on transmission line using MATLAB/Simulink

This paper has investigated the application of the definite time over-current (DTOC) which reacts to protect the breaker from damage during the occurrence of over-current in the transmission lines. After a distance relay, this kind of over-current relay is utilized as backup protection. The overcurrent relay will provide a signal after a predetermined amount of time delay, and the breaker will trip if the distance relay does not detect a line failure. As a result, this over-current relay functions with a time delay that is just slightly longer than the combined working times of the distance relay and the breaker. This DTOC is tested for various types of faults which are 3- phase fault occurring at load 1, 3-phase fault occurring at load 2, a 3-phase fault occurring before primary protection, and the behaviour of voltage and current with a failed primary protection. All the results will be obtained using the MATLAB/Simulink software package.

Power Transformer Inrush Current Minimization During Energization using ANFIS based Peak Voltage Tracking Approach

Energizing the power transformer at no load causes inrush current flow. The value of this current depends on main three factors, the residual and saturation flux of the transformer core, the rating of the transformer, and the switching instant. Inrush current may decrease the life of the transformer and causes mall function of the protective relays. Many efforts were done for limiting the inrush current using a current limiter or improve the core material to reduce residual flux. Other treating is to control energizing instance. This paper focused on controlling the instant of the transformer energization switch using fuzzy logic inference system. A new technique depends on adaptive seeking the crest of the voltage waveform. By this method there is no need to zero-crossing technique or phase looked loop. At this point, the flux of the core reaches the minimum value. Simulation and laboratory results show the success of this technique in reducing the inrush current. This technique gives the freedom to the operational engineering for energizing the power transformer at any time.

A Decision Tree Based Ultra-high-speed Protection Scheme for Meshed MMC-MTDC Grids with Hybrid Lines

The reliable operation of modular multi-level converter based multi-terminal high voltage direct current (MMC-MTDC) grids requires high-speed and selective DC line protection. A single-ended protection technique is proposed for MTDC grids with offshore wind farms and hybrid lines that involve overhead lines and submarine cables in series. Positive and negative poles’ currents at one end of each line section are analyzed using discrete wavelet analysis (DWA). To classify fault type and identify fault zone, a fine decision tree is supplied with an energy index and the envelope slop of detail 1 coefficient (D1) obtained from DWA. Only 0.2 ms following the fault inception are needed for calculating the energy index and the envelope slope to perform relay functions. The approach was tested on a three-terminal two-poles ±\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\pm$$\\end{document} 400 kV MMC-MTDC model. The simulation results validate the effectiveness of the suggested protection technique under various fault scenarios, even with up to 200 Ω fault resistance. The proposed technique is not only able to detect the faulty line, but also it identifies overhead line faults and submarine cable faults for hybrid type lines. Moreover, the proposed technique is not affected by wind power injection changes, AC faults, or data noise. The simulated model was produced in the MATLAB/Simulink platform.

Integrating power quality analysis and protection relay functions

In the paper the implementation of power quality analysis functions in protection relay has been presented. The main focus of the research has been on the development of efficient algorithms for voltage and current signals frequency spectrum determination with harmonic and interharmonic content up to 2 kHz. The technique that enables efficient implementation of frequency spectrum determination in protection relay employed in systems with varying line frequency is resampling in the digital domain. The accuracy analysis of the resampling technique applied in a protection relay, taking into account implementation issues, has been carried out.

ANALISIS KEANDALAN, KOORDINASI PROTEKSI. RELAY STANDBY EARTH FAULT (SBEF), SAAT TERJADI FAULT PADA GARDU INDUK MAROS

The need for the use of electric power in modern times has experienced many developments in the field of technology, which of course has an effect on the amount of electricity consumed in society. Along with the rapid demand for electricity in Indonesia. The reliability of the electric power system is key to meeting the community's needs for electrical energy. This is due to the increasing number of human activities that require electrical energy.
 This study aims to analyze the reliability of protection coordination, working principles, security, and SBEF relay simulation when a fault occurs at the Maros substation. The method of data collection and direct observation in the field was carried out precisely at the Maros 150 kV Substation, the Maros Transmission and Substation Service Unit (ULTG).
 The results of the study, namely the reliability of the SBEF relay protection coordination when a fault occurs at the Maros substation, show that the first relay to work is the OCR GFR on the feeder side because, based on the working current settings and working time, if given a fault current of 3021 A, it will work after 426 ms, followed by the incoming side GFR OCR relay, SBEF stage 1 Fault percentage = 0075% so that it has a reliability percentage of 100%. The working principle and safeguards carried out on the SBEF relay when a fault occurs at the Maros substation and the data recap of the Maros ULTG fault can be seen by comparing the frequency of faults that cause the transformer to go out before and after the implementation of the two-stage SBEF relay function and the frequency of faults that cause the transformer to go out at ULTG Maros in 2019 as many as 1times and in 2020 as many as 0 times. The simulation on SBEF when a fault occurs at the Maros substation on the transformer uses the ETAP 19.0.1 application; the first time it works is GFR.

Relay demonstration on board for final year student

The present invention relates to a relay demonstration board, characterized by a microcontroller, numbers of relays are connected to the microcontroller by a plurality of switches, wherein the first relay is connected to a light bulb for controlling the lighting of the bulb and the second and third relay are connected to a DC motor for controlling the rotational direction of the motor. Accordingly, these objectives may be achieved by following the teachings of the present invention. This invention relates to a relay demonstration board for teaching and learning purpose. An electrical relay is an electromagnetic switch operated by a relatively small electric current that can control a much bigger current and thus enable both circuits to be electrically isolated from each other. Relays have been used in wide variety of applications such as home appliances, digital computers and automation system due to its simplicity, long life and high reliability. The project present invention relates to a relay demonstration board. It is developed to allow students to understand the function of relay and how to connect relay in circuit. The major components include three relays, one light bulb and one direct current (DC) motor. The relays are used for control purpose while the light bulb and DC motor are used as the output. Furthermore, the light can be connected in alternating current (AC) or DC circuit to show students how to connect AC circuit and DC circuit. Besides, this tool are invention can be connected to an external microcontroller such as an Arduino board to provide input and or signal to the circuit.

Development of Automatic Hydroponic Plant Watering Based Arduino Microcontroller

This paper aims to develop a design for an automatic hydroponic plant nutrient sprinkler. This plant watering device used an Arduino Mega 2560 microcontroller as the interface and an LCD (Liquid Cristal Display) as a display to indicate nutrient levels. The device design deployed a time system set using an Arduino microcontroller and RTC (Real Time Clock) based watering time settings. The development of this automatic nutrient watering device was equipped with a TDS (Total Dissolve Solid) sensor, which reads the value of the nutrient solution content in the water. The LCD displayed monitoring system performance and the relay functions to turn on and off the water pump connected to the hydroponic media watering pipe installation. The benefits of the device can save time and energy. Therefore, the device is more efficient than the manual watering system.

Function and role of bus bar protection relay in distribution substation

AbstractBus bar of substations are important equipment where multiple facilities are centrally connected, and the impact of a fault is significant. Therefore, bus bar protection relays have unique functions to correctly detect the point of fault, which allows high speed fault elimination and minimization of outage area. This paper describes functions and roles of bus bar protection relays applied in distribution substation of Kansai Transmission and Distribution. After describing the concept of installation of bus bar protection relays, recent trends in device development tailored to the bus bar configurations of substations and the unique functions of bus bar protection relays are introduced. The retrofit methods that are being increasingly applied as a renewal solution for bus bar protection relays are then described, as well as prospects for bus bar protection functions in the future IEC 61850 full‐digital substations.

Monitoring Penyiraman Aglonema Lulaiwan Otomatis Berbasis IoT Dengan Sensor Soil Moisture dan DHT11 Menggunakan Aplikasi Telegram

IoT-Based Automated Aglonema Lulaiwan Watering Monitoring With Soil Moisture and Dht11 Sensors Using the Telegram Application is designed to assist users in monitoring and watering plants. This study aims to inform the user that the plants lack water or not and in watering so as not to overwater. This study uses devices such as Base NodeMCU ESP8266, NodeMCU ESP8266, Sensor Soil Moisture, DHT11, Relay, Box 9V Battery, 9V Battery, LCD16x2 I2C, Mini Pump and telegram application, This Mini Pump works if the soil moisture is below 50%. This Aglonema plant watering system works automatically which uses a Soil Moisture sensor to measure soil moisture, DHT11 to check the temperature around the plant, The relay functions to turn off the Mini Pump, The Mini Pump works as a dispensing of water to the plants and the telegram application functions to provide notifications to check soil moisture and temperature around the plants. With this automatic watering system can help users determine soil moisture.

Optimization of the Spacecraft Transfer Maneuver from a Point of the Elliptical Orbit to Another Point of the Same Orbit

The problem of changing the orbital position of the spacecraft located in some elliptical orbit in the Newtonian gravitational field is analyzed. It is assumed that the spacecraft is equipped with a non-adjustable engine that can be activated multiple times. An algorithm for determining the optimal (according to the criterion of the minimum characteristic velocity) transfer scheme has been developed. Special attention is paid to the analysis of the number of active segments on the trajectory and their location on the trajectory revolutions. The algorithm is based on the maximum principle and the method of parameter continuation. The initial approximation for the transfer scheme is found using the trajectory of the optimal transfer of the spacecraft with a perfectly adjustable propulsion system (engine of limited power). This trajectory is then continued for the spacecraft with a non-adjustable engine, introducing a smoothing parameter for the thrust function. In the final stage, the characteristics of the optimal transfer pattern are determined for the spacecraft with a non-adjustable engine involving a relay thrust function. The properties of the optimal scheme of the maneuver as a function of the angular distance of transfer (the number of revolutions of the trajectory) and a function of the phasing angle (the angle characterizing the angular distance between the points of the orbit where the transfer takes place) are analyzed. It is shown that an increase in the angular distance of the transfer significantly reduces the characteristic velocity of the maneuver even at large phasing angles.

Presenting grammar through Internet memes in teaching English for specific purposes

The article discusses the potential of using Internet memes in teaching a foreign language. We consider an Internet meme to be a set of semiotic signs. This approach explains the potential of Internet memes application in educational process since most of the language learning methods rely on semiotic elements. Internet memes are multimodal structures that can be used as an efficient tool for presenting material in teaching English. Memes are classified into verbal, nonverbal and complex ones (combining image and verbal element). A set of sample memes presenting the combination of images and verbal elements has been selected to demonstrate the process of meaning making, which is an integral part of mastering a foreign language. Due to the importance of visual perception in learning process and the very nature of Internet memes as widespread forms of expression and communication existing in visual format, the use of them if beneficial for both teachers and learners. The elements of the sample memes are analyzed in terms of Roland Barthes’ theory of image narrative potential. We provide the evidence that anchorage and relay functions of linguistic messages account for the process of meaning making. In terms of semiotics the effects of text and image combination are examined in detail. Special attention in the article is given to the ways of memes application and the effectiveness of their use in the in-class and out of class learning process for practicing a grammar phenomenon of modality. Memes demonstrate a modal construction in the situation close to real life providing a sample of using it in context and provoking imitation of real-life situation by student. The humorous effect inherent to Internet memes is aimed at achieving a reaction from numerous addressees, thus making memes an efficient tool for teaching/learning a foreign language due to an expected feedback. Special attention has been paid to Internet memes containing constructions with modal verbs expressing irony and paradox. The article provides tools of teaching English modals via memes as well as experiment results and their analysis. The study reveals positive results of the experiment in terms of efficiency of using Internet memes in educational process that demonstrates better results in learning new material as well as a higher level of students’ involvement and creativity.

Smart Assistance for Safe Driving

An accident is a life changing, shocking, abrupt, and unexpected external action which occurs at an instance and at any place, with no apparent fault or deliberate reason but with major impacts. Carelessness of the driving force is the major factor of such accidents. The traffic authorities provide a lot of instructions to the vehicle operators. But many of them don't obey the principles. In today’s day of age ensuring that riders follow safety protocols is much more difficult than anticipated for the government to track and regulate. But still the principles are being violated by the users. so as to beat this we introduce an intelligent system, Smart Helmet, which automatically checks whether the person is wearing the helmet and has nonalcoholic breath while driving. Here we've a transmitter at the helmet and therefore the receiver at the bike. there's a switch wont to sure the wearing of helmet on the top. The switch is in ON condition ensures that the helmet is placed and safely secured by the rider. An alcohol detecting sensor is placed near to the mouth piece of the rider at the inside of helmet to detect the presence of alcohol. The data to be transferred is sent using LoRa Module from transmitter on helmet. The receiver at the bike also receives the data through LoRa. The engine should not be able to turn ON if any of the two conditions is violated. Main control unit has complete control over the function of relay and thus control over the ignition, it is able to control the engine via a relay and an interfacing circuit.

Use of synchronized vector measurements technology for perform relay protection functions

RELEVANCE. Recently, along with the initial scope of synchronized vector measurements (synchrophasor) technology associated with Wide Area Measurement System (WAMS), more and more attention is paid to expanding the scope of this technology. Digital substations are one of the places for generating synchrophasor signals, at the same time, synchrophasor data are proposed to be used for the purposes of relay protection and automation at the digital substations itself, which will facilitate the construction of centralized relay protection systems at the substation. THE PURPOSE. Consider the use of synchrophasor technologies at a digital substation of the fourth type, as a replacement for Sampled Values (SV) signals. Consider additions to the standard set of synchrophasor signals necessary for the operation of various relay protections at a digital substation. Perform an analysis of the accuracy of calculating the synchrophasor when the frequency of the controlled current and voltage changes relative to the nominal value, when higher harmonics appear in the measured signal. Develop a pre-computation technique for relay protection algorithms. METHODS. When solving the problem, the method of calculating the total measurement error of the synchrophasor TVE (Total Vector Error) was used - a value that characterizes the deviation of the amplitude and phase of the measured vector from their specified values. CONCLUSION. The use of synchrophasor signals with the necessary additions for the operation of relay protection reduces the load on the digital network of the digital substation, simplifies the operation of relay protection algorithms. Calculations have shown that the measurement errors of synchrophasor do not go beyond the specified parameters. The proposed methods of precomputation allow to speed up the work of relay protection algorithms.

Current Issues and Solutions for Protection and Control Panel in Distribution Substation

In December 2020, the “Green Growth Strategy for Carbon Neutral” was launched, and it is expected that more distributed power sources will be introduced into distribution system in large quantities. It is necessary to streamline equipment and reduce costs. Efforts include centralizing the functions of protection relay units and automatically setting the target voltage of transformers for distribution substations. By realizing these, we aimed to slim down the equipment and reduce the cost. Therefore, in this paper, we report on the specific contents of the integrated protection relay function.

Nucleus incertus projections to rat medial septum and entorhinal cortex: rare collateralization and septal-gating of temporal lobe theta rhythm activity

Nucleus incertus (NI) neurons in the pontine tegmentum give rise to ascending forebrain projections and express the neuropeptide relaxin-3 (RLN3) which acts via the relaxin-family peptide 3 receptor (RXFP3). Activity in the hippocampus and entorhinal cortex can be driven from the medial septum (MS), and the NI projects to all these centers, where a prominent pattern of activity is theta rhythm, which is related to spatial memory processing. Therefore, we examined the degree of collateralization of NI projections to the MS and the medial temporal lobe (MTL), comprising medial and lateral entorhinal cortex (MEnt, LEnt) and dentate gyrus (DG), and the ability of the MS to drive entorhinal theta in the adult rat. We injected fluorogold and cholera toxin-B into the MS septum and either MEnt, LEnt or DG, to determine the percentage of retrogradely labeled neurons in the NI projecting to both or single targets, and the relative proportion of these neurons that were RLN3-positive ( +). The projection to the MS was threefold stronger than that to the MTL. Moreover, a majority of NI neurons projected independently to either MS or the MTL. However, RLN3 + neurons collateralize significantly more than RLN3-negative (–) neurons. In in vivo studies, electrical stimulation of the NI induced theta activity in the MS and the entorhinal cortex, which was impaired by intraseptal infusion of an RXFP3 antagonist, R3(BΔ23-27)R/I5, particularly at ~ 20 min post-injection. These findings suggest that the MS plays an important relay function in the NI-induced generation of theta within the entorhinal cortex.

Key-count differential-based proactive key relay algorithm for scalable quantum-secured networking

By overcoming the distance limit in quantum key distribution (QKD) technology, key relaying over trusted nodes is regarded as an essential function for practical quantum-secured networking. The key relay function consumes a series of costly quantum key resources to establish an end-to-end key in QKD networks (QKDNs); thus, an efficient key relay algorithm is required. To investigate this problem, we developed an integer linear programming (ILP) formulation that maximizes a balanced summation between max-min fairness and efficiency in the key relay. Inspired by the ILP model, this study developed a key-count differential-based proactive key relay (DPKR) heuristic algorithm to provide a scalable solution for key relays in QKDNs. The proposed DPKR algorithm iteratively selects a set of nodes by considering the key-count differential between nodes and establishes an end-to-end key by relaying it over the selected nodes. Owing to the proactive key relay model, an effective key relay route in the key management layer in the QKDN can be calculated solely by the key-count status in the key management layer. The proposed DPKR algorithm reduces manifold order-of-magnitude in the algorithm computation time at the cost of an acceptable loss in the average and minimum numbers of keys from those of the ILP optimization model. The computation time evaluation clearly manifests a scalability of the DPKR algorithm in quantum-secured networking.