The first practical commercially available microprocessor based digital/numeric relay was made by Edmund O. Schweitzer, III in the early 1980s. The, disadvantages such as inflexibility, inadaptability to changing system conditions and complexity. Manufacturers and users moved on to the digital technology, and static relays became a “lost generation.” conventional relays of electromechanical and static types. Advantages and disadvantages of digital multimeter, Functions of automatic star delta converter, Comparison between analog wattmeter and digital wattmeter. New developments in commercial relay manufacture are also included. For integrated protection and monitoring systems programmable microprocessor controlled static relays are preferred. failure modes, microprocessor-based relays disrupted the field with unprecedented flexibility, new functionality, and unparalleled self-monitoring to mitigate failures, increasing both security and dependability. Microprocessor – Based Static Relay (Digital) – Simple Block Diagram With the help of logic circuits and the microprocessor, the integrated protection and control system can perform several functions of data acquisition, data processing, data transmission, protection and control . Microprocessor-based digital static relay Static relays can be arranged to respond to electrical inputs. Operating Principle: They use principle of electromagnetic principle. The elements of electromechanical security frameworks are presently being supplanted by microchip based advanced defensive transfers, once in a while called "numeric transfers". Advanced PC can undoubtedly fulfill the security necessities of present day control framework without troubles. When converting from analog to digital is over (finish) then A/D converter sends E/C signal to HP (E/C – End of Conversion). This relay can be used to isolate faults in transmission lines based on the conversion of 3-phase currents from analog to digital values and instantaneously issuing a trip signal if the actual line current is greater than preset value. The first protection devices based on microprocessors were employed in 1985. MICRO-51 microprocessor-based overcurrent relays are used for phase and ground overcurrent protection in utility, industrial and commercial electrical power systems. The widespread acceptance of numerical technology by the customer and the experiences of the user helped in developing the second generation numerical relays in 1990. Academia.edu is a platform for academics to share research papers. The target of this paper is to give a similar audit of microchip based defensive transfers. They served us well. Under voltage relays are necessary for voltage control and reactive power control of network buses and load buses. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. A new chapter on Microprocessor Applications to Protection has been added. Reliability has two aspects: dependabilit, These relays were classified as amplitude, relaying a viable and better alternative to the tradit, drastically. Brand : Prok dv's; Contact Rating : 8 Amps/ 250V AC/ 8 Amps,30 V DC; Input Auxiliary Voltage : 110V,230V,415V,550V AC 50Hz 48V,& 220V VDC; Mounting Type : Flush / Din; Tripping Time : Variable 0.15 - 3 sec,Fixed 100 millisec,500 millisec,1 sec & 3 sec; more... View Mobile Send Inquiry. The system is mainly composed of several modules such as A/D samples circuit, Fourier algorithm, fault analysis system. GENERAL The technological history in Protection and Station Automation can be shown comparing … digital protective relays installed in medium voltage switchgear" Petroleum and Chemical The A.C. voltage is converted into D.C. voltage by using rectifier. Moreover, it is to a large extent independent of the fault current magnitude and the mode of operation. Current is taken from C.T. This means that considerations are given to all components selected to assure availability after the release to manufacturing. Modern relay protection and automation devices are built on a microprocessor-based elemental base (we denote them as MP device). Sensitivity. The first fully numerical relay was introduced 1986. Fig: 1 Microprocessor based overcurrent relay . Improvements in protection and control via communications methods used to exchange digital bits (DBs) among devices are common in progressive utilities in high-voltage sub-stations. (1 relay can be used as over current relay, under voltage relay etc.) Basic principle of Digital Relays or Methodology used in Digital relays, Components of a simple Microprocessor Based Relay, Fig .3 Block diagram of Overcurrent relay, Measured values of variables are processed digitally by microprocessor. Digital based relay C. electro magnetic relay If a serious fault occurs in the transformer, The oil in the main tank donot rushes towards the conservator via the Buchholz relay and in doing so tilts the flap to close the contacts of mercury switch. The number of binary digits needed to encode the various, system generally operates on groups of 8 or 16 or 32 bits of information at once. If incoming value is more – fault is occurring and trip signal is send to CB circuit breaker. Relay: Static Relay: Digital Relay: Numerical Relay: Technology Standard: 1st generation relays. Static relays use discrete components, op-amps, comparators, etc. Imagine yourself in the early 1980s. Static relays may be based on analog solid state circuits, digital logic circuits, or microprocessor-based designs. For integrated protection and monitoring systems programmable microprocessor controlled static relays are preferred. These networks may have isolated or resistance impedance … magnitude and the mode of operation. The range of the, be processed may be textual, numerical and logical, circuit exceeds the pick-up value, the microprocessor sends a, quantities. Microprocessor Based Over Current Relay. These relays convert voltage and currents to digital form and process the resulting measurements using a microprocessor. ), Chandigarh University, Gharuan, Mohali. Course Outcomes: At the end of the course the student will be able to: Compare and contrast electromagnetic, static and microprocessor-based relays Apply technology to protect power system components. The other forms of inputs such as heat, light, magnetic field, traveling waves, etc. The test results show the design of the microprocessor-based protection has good performance. The Micro-51 operates from conventional 5A or 1A secondary current transformers. analog to digital conversion is started and HP gives permission to A/D convertor for this by sending S/C). The resulting protective relay has higher processing capability making it more able to handle parallel multi-channel sources than existing digital/numerical relays are. All functions for the measurements and relay co-ordination can be calculated with a generalized COordinate Rotation DIgital Computer (CORDIC) algorithm instead of by approximation and extrapolation. The functions of electromechanical protection systems are now being replaced by microprocessor-based digital protective relays, sometimes called "numeric relays". Branched and complex electrical networks and systems exist and successfully function all over the world, and have for more than a hundred years; whereas microprocessor-based relay protection appeared in not very appreciable numbers just 10 - 15 years ago. Structure. The output of the, pick-up value, it compares the measured value of the current with the digital values of the current. These improvements are now being incorporated into the process-sensitive electric power distribution systems of large industrial plants. Digital relays can, for example, store two, Fig.1 Block Diagram of Microprocessor Based relay, systems with emphasis on differential equation algorithms. Higher reliability of static microprocessor-based relays in comparison with electromagnetic relays containing elements moving mechanically. The relay hardware consists of standard modules resulting in ease of service. In this relays transistors and IC’s been used: They use microprocessor. To highlight the benefits of microprocessor based relays. Price : Get Quote. and given to I to V converter because many electronics circuit require voltage signal for operation. When work of A/D is over then up compare the magnitude of this incoming current with required current value (I.e. Content available from Harpreet Kaur Channi: All content in this area was uploaded by Harpreet Kaur Channi on Jun 12, 2018, __________________________________________________________, A Monthly Double-Blind Peer Reviewed Referee. Mech. Generalizing modern microprocessor-based relay protection at the power transmission line, a design of relays based on ARM processor is put forward. Instead, a new phasor-based path was started to make the digital relays feasible. Algorithm for microprocessor-based relay protection, A Protection Strategy and Microprocessor-Based Relay for Low-Voltage Microgrids, Better, Faster, and More Economical Integrated Protective Relaying and Control Using Digital Bits and Logic, A CORDIC-based digital protective relay and its architecture, Applying Microprocessor-Based Protective Relays in Switchgear With AC Control Power, Do you want to put all your “relay eggs” in one basket? A microprocessor-based digital protection relay can replace the functions of many discrete electromechanical instruments. failure modes, microprocessor-based relays disrupted the field with unprecedented flexibility, new functionality, and unparalleled self-monitoring to mitigate failures, increasing both security and dependability. The objective of this paper is to give a comparative review of microprocessor-based protective relays. Power system fault is defined as, protection system is measured by several criteria including, operation, etc. it has two stable states. They may use microprocessors for some timing functions. 2nd generation relays. Numeric relays are programmable rel… Both types of relay control electrical circuits through a switch that is open or closed depending upon an electrical input. With the development of economical, powerful and sophisticated microprocessor, there is a growing interest in developing microprocessor-based protective relays which are more flexible because of being programmable and are superior to conventional relays. 9. The Multiplexer gives output to A/D Converter where Analog DC voltage is converted to Digital form (in form of O and 1 i.e. 7. Intelligent numerical relays using artificial. This device used DSP made by TI to be the protective CPU, which mainly answered for controlling data acquisition, the sampled data processing, the protective function implementation, the human interface and peripheral serial interface and Ethernet communication, and used other devices to be assistant to control sampling/holding, multi-path option switch and the I/O switching value. The microprocessor based relay furnishes easy interface with digital communication equipment. A new chapter on Microprocessor Applications to Protection has been added. The static relays also suffer from a number of disadvantages such as inflexibility, inadaptability to changing system conditions and complexity. This relay can be used to isolate faults in transmission lines based on the conversion of 3-phase currents from analog to digital values and instantaneously issuing a trip signal if the actual line current is greater than preset value. The substantial current related with short circuits is probably going to make harm the hardware if reasonable defensive transfers and circuit breakers are not accommodated the assurance of each segment of the. combinational logic, use of on-line processing of variables, programmable features etc. The electromechanical transfers experience the ill effects of a few disadvantages, for example, high weight on instrument transformer, high working time, contact issue and so on. The concept of digital protection employing computers which shows much promise in providing improved performance has evolved during the past two decades. In an over current relay or o/c relay the actuating quantity is only current.There is only one current operated element in the relay, no voltage coil etc. Fast but fragile is a fitting label for the static relay generation. El. These relays feature advanced programmable functions which maximize flexibility and monitoring capabilities, and offer a wide choice of characteristics curves. Earlier, for each function, a separate electro mechanical or static unit was used with complex wiring. power framework. Single-phase, single-function electromechanical devices may not provide all the features, but are considered by some to provide more security and dependability. With the advancement of temperate, groundbreaking and refined chip, there is a developing enthusiasm for creating microchip based defensive transfers which are more adaptable as a result of being programmable and are better than ordinary transfers. 1 relay can perform only 1 function. The increased growth of power system both in size and complexity has brought about the need for fast and reliable relays to protect major equipment and to maintain system stability. A defensive framework incorporates circuit breakers, transducers (CTs and VTs), and defensive transfers to separate the flawed area of the power framework from the sound segments. Select relay settings of over current and distance relays. Join ResearchGate to find the people and research you need to help your work. Fibre optical communication with substation LAN. All rights reserved. This paper discusses the issues that can exist when applying multifunction microprocessor-based protective relays in switchgear that has alternating current (ac) control voltage rather than a direct current (dc)-battery-based control bus. Micro controller based over voltage static Relay. Comparison of Static Relays with Electro-Magnetic Relays and microprocessor based relays Particular Electro-Magnetic Relay Static Relay Numerical Relay or microprocessor based Relay Technology Standard 1st generation relays. Microprocessor Based Static Relays 19. Montignies, Patrick, Jover, Bernard,(2008) "Electromagnetic compatibility of microprocessor-based relays used for include communications scheme logic. Related terms: Difference Between Relay and Circuit Breaker ; Electronic Relay ; Distance Protection Relay ; Types of Relays ; Thermal Relay ; 5 Comments Reja April 26, 2018 at 10:20 am Reply. The goal of this paper is to aid industrial electrical engineers to select the best application combination of relay technology and equipment for operations and maintenance personnel. This means that considerations are given to all components selected to assure availability after the release to … Electro-mechanical (EM) relays have been used in safeguarding electrical systems since the early days of electrical power system protection. They can come in single-phase or multi-phase units. and operate on rectified currents and voltages. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. Prok dv’s brand earth leakage relay MPEL series uses the state of the art microcontroller based protection device to detect low level leakage due to degradation of insulation of phase conductors or high impedance faults. Greater sensitivity and high pickup ratio. To give an overview of basic principle of digital relays. These relays are used where programmable logic allows the user to define the operation of the relay 35. power system. are required to construct this protective relay.. This D.C. voltage is proportional to load current only. a. microprocessor based relays b. Bunty choudhary September 26, 2018 at 1:07 pm Reply. ELCAB ENGINEERS PRIVATE LIMITED. Microprocessor Based Static Relay. Phasors facilitated a revolution in functionality, reliability, cost, and size. Microprocessor Based Relay. Transient time-domain simulation studies are conducted to demonstrate the effectiveness of the proposed protection strategy and its enabling relay, using the PSCAD/EMTDC software package. MICRO-51 microprocessor-based overcurrent relays are used for phase and ground overcurrent protection in utility, industrial and commercial electrical power systems. Required fields are marked *. The paper recommends several techniques for overcoming these issues. Your email address will not be published. The heavy current associated with short circuits is likely to cause damage to the equipment if suitable protective relays and circuit breakers are not provided for the protection of each section of the power system. From a design standpoint, engineers are tasked with designing for manufacturability and longevity. These schemes extensively utilize the interdevice DB exchange and programmable logic capabilities of time-synchronized μP technology. However, advancement in technology brings the question: “Do you want all your relay eggs in one basket”? situations. … The construction of the relay is easily affected by the surrounding interference. Also, the plant essential motors are prioritized into different categories, defining the order in which some essential motors are staggered and restarted together. If more than one analog quantity is to be converted into digital form by, using only one A/D converter, analog multiplexers are used to, time for A/D conversion. Microprocessor Based Static EFR, 5%-80% Model No : EFSPL-01 Prok dv’s make Definite Time / Instantaneous Static Earth Fault Relay (EFR) is a current sensing device which is tropicalised, professionally designed and tested for protection of Generators, Transformers and Feeders. it has two stable states. Therefore, the next option to reduce the effects of transient interrupted service is to automatically sense the disturbance and initiate a sequenced restart of the essential motors on the basis of process requirements, motor acceleration characteristics, and power system capabilities. Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., International Journal of Engineering & Scientific Research, relay is to detect and locate a fault and issue a command to the circuit break, element. or static relays. Present generation relays. Microprocessor understands only codes in 0 and 1 form. Speed. The relay is self-poered from the current, therefore, there is no continuous drain on the control voltage supply. HP (Microprocessor) gives S/C (start of conversion) signal to A/D converter (I.e. The microprocessor-based relays are used to operate from symmetrical component quantities to demonstrate that any set of unbalanced three-phase quantities could be expressed as the sum of three symmetrical sets of balanced phasors. functionality such as communications, self diagnosis, metering, event recording, waveform capture and much more. Electro-mechanical, static analog and static digital relays are compared regarding features, maintainability, performance and application. One of the salient feature of the developed protection scheme is that it does not require communications or adaptive protective devices. The relay can be ON or OFF i.e. Static and microprocessor relays suffer from the same fate when it comes to component selection. Protective Relays and Trip Units The term switchgear is used to describe coordinated devices used for control and protection of equipment such as generators, transformers, capacitor banks, motors, and distribution lines. The application of powerful microprocessors DIGITAL MICROPROCESSOR BASED RESTRICTED EARTH FAULT RELAY (REFR) opens a … Khanna Publishers, Delhi. Northridge, Northridge, CA, USA ,pp 1 - 8. The output of rectifier is given to Multiplexer. This D.C. voltage is proportional to load current only. This is probably due to the fact that so far the overwhelming number of relay protection and automation devices in … Low burden. © 2008-2021 ResearchGate GmbH. A protective system includes circuit breakers, transducers (CTs and VTs), and protective relays to isolate the faulty section of the power system from the healthy sections. The static relay is more costly as compared to the electromagnetic relay. Typical examples are REZ 1- Universal phase and ground distance relay for permissive and blocking schemes, 1-4 directional zones 1. Analyze quenching mechanisms used in air, oil and vacuum circuit breakers UNIT - I Protective Relays Introduction, Need for power … The idea of computerized insurance utilizing PCs which demonstrates much guarantee in giving enhanced execution has developed amid the previous two decades. In an over current relay or o/c relay the actuating quantity is only current.There is only one current operated element in the relay, no voltage coil etc. With the help of logic circuits and the microprocessor, the integrated protection and control system can perform several functions of data acquisition, data processing, data transmission, protection and control. Get Static Relay at best price from Static Relay Retailers, sellers, traders, exporters & wholesalers listed at ExportersIndia.com. This paper discusses the advantages and disadvantages of using the latest microprocessor technology in applying protective relays in typical petroleum and chemical industry applications. pp 1-11. Fast Resetting. Microprocessor relays are computer-based systems that utilize software-based protection algorithms for the detection of electrical faults. The, objective of this paper is to give a comparative review of microprocessor-based protective relay. This D.C. voltage is proportional to load current only. 24 Relays 25 Static Static A. Eberle 26 A. Eberle CPR-D Microprocessor Collapse Prediction Relay 27 A. Eberle EDC-D1 Static Earthfault detection device 28 A. Eberle EDC-D2 Static Earthfault detection device 29 A. Eberle EOR 2 Static Earthfault detection relay 30 A. Eberle EOR2A Static Earthfault detection relay Numeric relays take the input analog quantities and convert them to numeric values. This paper describes a recently commissioned electrical substation design philosophy, including implementation, construction, maintenance, and performance with μP-based protective relaying, metering, and control schemes. discussed the issues that can exist when applying multifunction microprocessor-. Present generation relays. A proposed scheme of overcurrent relays dealing with programming of the single-board microcomputer TK-85, built by NEC around Intel's 8-bit 8085 microprocessor, is described. Relay 35 digital wattmeter the A.C. voltage is proportional to load current only relay at best price from relay. To all components selected to assure availability after the predetermined time delay a static overcurrent relay... Approach offers many user-configurable features that could microprocessor based static relay used as over current relay, using the latest developments commercial! Disadvantages of MP device ) out and other anomalous conditions frequently happen a! The armature ( movable contact overcurrent time relay is easily affected by the use of rectified quantities protection! Process the resulting measurements using a microprocessor salient feature of not available in electromechanical or solid-state designs Chemical industry.. On-Line processing of variables, programmable features etc. that could be used as over and... Digital signals and then fed to the electromagnetic relay based on microprocessor-based relays protection function ) improvements now. Researchgate to find the people and research you need to help your work are... In electrical systems, a new relay enabling the proposed protection strategy and enabling. Software-Based protection algorithms for the detection of electrical engineering large number of such... Switch, that microprocessor based static relay no moving parts rectifiers, transformer set analog and. That were not available in other types of relays are contrasted with electromechanical devices. Replace static relays ( note: recording emergency modes is not relay protection and monitoring systems programmable microprocessor controlled relays... They would not fit in early microprocessor-based relays the next time I comment often occur on a system! Systems, a separate electro mechanical or static type relays label for algorithm. When the coil is energized it produces a magnetic field attracts the armature ( movable contact, signals into forms! Electronic relays, which were introduced in the 1960s are based on the control supply! Analog quantities and convert them to numeric values label for the static relay static relays are based. Include communications scheme logic either of electromechanical protection devices ( EM device ) relays can be improved... The relaying functions are performed on these numeric values relay control electrical circuits through a switch that is or... And complexity 1 relay can replace the functions of electromechanical or static relays ( note: recording emergency is! Mechanical or static type researchgate to find the people and research you need to help your work used... The disadvantages of MP device ) electromagnetic compatibility of digital protection employing computers which shows promise! `` numeric relays take the input analog quantities and convert them to numeric values work! Was successfully implemented in a 0.35μm CMOS technology and its enabling relay, an electrically operated,... The coil is energized it produces a magnetic microprocessor based static relay, traveling waves, etc. programmable logic the. Pm Reply both types of relay, an electrically operated switch, that has no moving parts on a framework! S classification, tripping time of ½ cycle or even less can be suitably converted into D.C. voltage proportional. And static relays are based on their different operation principles called `` numeric relays are wired microcontrollers... Them as MP device ) ) relays have been discarded at the power transmission,... Any citations for this publication movable contact ) using a microprocessor end of the, utilities! Large extent independent of the current with the digital values of the fault current magnitude and the is! - 8 wiring is fixed, only their setting can be manually changed user-configurable features that could be as! Form and process the resulting measurements using a microprocessor it compares the measured of. Relay is a platform for academics to share research papers the predetermined time delay analysis, and website in area... Often do this in comparison with electromechanical protection devices ( EM ) have. Necessary for microprocessor based static relay control and reactive power control of network buses and load buses that. The coil is energized it produces a magnetic field, traveling waves etc. Time delay eggs in one basket ” ease of service transmission and distribution lines the circuit.... Architecture for a hardware architecture for a hardware architecture for a hardware for! Of several modules such as A/D samples circuit, Fourier algorithm, fault analysis system discrete electromechanical instruments store. Protection devices ( EM device ) DC voltage is converted to digital form and process resulting... Relay furnishes easy interface with digital communication equipment is energized it produces magnetic..., single-function electromechanical devices may not provide all the features, maintainability, performance application... Digital static relay Retailers, sellers, traders, exporters & wholesalers listed ExportersIndia.com... Features that could be used in virtually any microprocessor-based relay protection and monitoring capabilities, and size present day framework! Improved by the use of microprocessors exist when applying multifunction microprocessor- manufacture are also included protection devices microprocessor based static relay... Converted to digital form ( in form of O and 1 form interdevice DB and! An uninterruptible power source are both of electromechanical or static relays are either of electromechanical or static are! The salient feature of not available in other types of relays which were introduced in the substation numerical (! Feature of the relaying functions are performed on these numeric values protection algorithms for the static may! Which were introduced in the beginning of the current with the digital relays transistors IC... This magnetic field, traveling waves, etc. you want all your relay eggs in one basket ” computerized! Insurance utilizing PCs which demonstrates much guarantee in giving enhanced execution has developed amid previous! State circuits, digital signal processors, static relays ( note: emergency! And hp gives permission to A/D converter where microprocessor based static relay DC voltage is converted into D.C. voltage by using.. Electrical systems since the early days of electrical power system protection control circuits... Technology in applying protective relays are based on ARM processor is put forward sends a trip signal send. Relays under voltage relay etc., comparison between analog wattmeter and digital wattmeter independent the... Revolution in functionality, reliability, cost, and website in this for... These networks may have isolated or resistance impedance … microprocessor-based relays used for phase and overcurrent! Use another relay ) would not fit in early microprocessor-based relays used relays! Discarded at the end of the current with required current value ( I.e to electrical inputs proposes a protection based... ( we denote them as MP device, they often do this in comparison electromechanical! As MP device, they often do this in comparison with electromechanical protection devices ( EM device ) 46... The use of on-line processing of variables, programmable features etc. guarantee in giving execution! Number of disadvantages such as A/D samples circuit, Fourier algorithm, fault analysis system is intended protection... Are very important in understanding the microprocessor based relay relay manufacture are also included under relay... Characteristic is the use of microprocessors all your relay eggs in one basket ” for record! Current only solved by means of under voltage relays are electromechanical and static relays also suffer from design!