Adaptive digital protection relay

Abstract

The invention relates to an adaptive digital protection relay that is used instead of normal digital relays used in power generation and distribution centers in electrical networks, includes adaptive protection coordination features that facilitate troubleshooting coordination and automatically updates protection settings in all the relays, automatically reflects the change to the settings of all the protection relays by using communication between the relays and using the multi-agent system structure as a decision-making mechanism, provides the same cutting decisions as would be taken in a normal coordinated state as much as possible by using machine learning algorithms, consists of the parts of: input module (1), processor card (2), interface card (3), power supply card (4), communication ports (5), output module (6) and the process steps of reading the value (7.1), is there a fault? (7.2), is the adaptive protection active? (7.3), normal protection method (7.4), calculating the intervention time (7.5), sending messages (7.6), has the downtime passed? (7.7), intervene in circuit breakers (7.8).

Description

[0001] ADAPTIVE DIGITAL PROTECTION RELAY

[0002] Technical Field

[0003] This invention relates to an adaptive digital protection relay that is used instead of normal digital relays used in power generation and distribution centers in electric networks in the energy sector, that facilitates the process of troubleshooting coordination using the adaptive protection cooperation features, and that automatically updates the protection settings in all the relays, ensuring that the change is automatically reflected in the settings of all the protection relays by means of using communication between the relays and using the Multi Agent System (MAS) structure as a decision-making mechanism and that uses the machine learning algorithms to make the same cutting decisions (waiting time before cutting) as would be made under normal coordination, as possible.

[0004] Background of the Invention

[0005] A relay is an electromechanical or semiconductor device that performs a switching operation in electrical circuits. Typically, a relay has the ability to turn a high-power circuit on or off by means of a low-power controlled electromagnet or semiconductor component accordingly. The relays use the low-power signals in a control circuit in order to affect the high-power circuits that are intended to be switched.

[0006] The digital protection relays that are currently in use play an important role. In order to protect the system, it is of great importance that the protection relays that are used in electricity distribution and generation facilities open the circuit breakers in the system when short circuits or over-current / voltage situations occur. In addition, the digital relays constitute an important control element with their ability to continuously analyze the system and provide reporting accordingly. Some of the research in this area has been carried out to increase the efficiency, reliability and speed of the relays. As a result of this research, it was possible to develop multifunctional digital relays by means of using advanced processors. A multifunctional protection relay based on programmable gate arrays (FPGA) has been implemented and has versatile features. The protection relays that can handle fault conditions such as over-current have been designed using both FPGA and microcontroller platforms. Various protection relays have been designed with various protection schemes including overcurrent, overvoltage, undervoltage, overfrequency and underfrequency.

[0007] For smart electricity grids, new management and protection mechanisms are required as energy has a two-way transition and the number of power generators increases. Multi-agent systems are used in this area. A protection relay using a multi-agent system can be integrated with a wind energy generating system.

[0008] The machine learning method has also found many application areas in the smart grids. Managing distributed generation, load management techniques, smart homes and energy saving and load level prediction are some of these application areas. However, the machine learning is a rare research topic that finds application for the protection relays.

[0009] As explained, the protection relays available in the market have some limitations against multi-source generation, two-way energy transfer and changing loads, although they contribute significantly to the system. Even without any changes in the relay's protection and monitoring functions, the data input from the energy system is constantly monitored by the relay's monitoring functions. This data includes electrical parameters such as current, voltage and frequency. The internal settings include specified protection parameters and triggering conditions, and these settings are usually configured via software. When the protection relay detects that a certain condition is met, it initiates a fast and accurate response and activates the output signals. These signals affect the circuit breaker, interrupting the energy circuit and thus preventing the effects of negative situations on the system. It also provides information to the control system through feedback elements, which informs the operators about the status of the system and allows them to intervene when necessary. In a normal power line, the situation is as follows. A power source is a source that provides energy and is usually provided by power plants or distribution centers. The electrical energy generated from this source is transmitted via a power line. The power lines transfer energy from one point to another via transmission towers and poles. The load items connected to this line are devices or systems that consume electrical energy. In normal operation on the power line, the protection relays are not activated and the energy system operates smoothly. However, when a possible overcurrent, short circuit or other abnormal conditions occur on the power line, the protection relays come into play and trigger the circuit breakers by detecting these conditions. The circuit breakers prevent possible damage by interrupting the energy circuit.

[0010] However, in such situations requiring manual adjustment, adding a power source to the power line (change in the network) causes the relays in the system to be readjusted one by one through manual intervention. In this case, the need to provide coordination and adaptively re-adjust according to changing load and power factors arises from here. As a matter of fact, today's efforts to integrate micro-scale electric power generators using solar or wind energy into the grid further reinforce the need for a fast, smart and automatic protection system.

[0011] In this the invention, the adaptive protection relay is enabled to act in conjunction with other relays in order to eliminate some of the deficiencies of the currently used system. When a new network change occurs, the relevant protection relay automatically adjusts itself and ensures that the change in the network is transferred to other relays. In addition, in such systems with two-way power transfer, in the event of a fault, communication is established between the opposing relays closest to the fault and the decision to open the shortest circuit is taken jointly. However, in case of failure to communicate, a decision is made based on internal settings. In the adaptive relay design, by using machine learning algorithms, the decision to open the shortest circuit can be made despite the fault and communication interruption. Advantages of the adaptive protection relay:

[0012] 1 ) When an electrical change occurs, instead of manually adjusting all the protection relays, the relevant relay automatically adjusts itself and its new settings are transferred to the other relays.

[0013] 2) Due to its adaptive adjustment feature, it facilitates the integration of renewable energy sources and changing loads into the grid.

[0014] 3) Thanks to the machine learning method, it makes decisions to open the circuit autonomously and independently, faster and more resilient to communication interruptions between the relays.

[0015] The structural and characteristic features and all the advantages of the invention will be more clearly understood due to the figures shown below and, the details referring to these figures and, thus the assessment should be made considering these figures and the details.

[0016] Figures Helping to Understand the Invention

[0017] The invention will be explained with reference to the attached figures so that the features of the invention will be understood more clearly. However, it is not intended to limit the invention to these particular embodiments. On the contrary, it is intended to cover all the alternatives, modifications and equivalents which may be included within the scope of the invention as defined by the appended claims. It is to be understood that the details shown are presented solely for the purpose of illustrating preferred embodiments of the present invention and are presented for the purpose of providing the most useful and easily understandable description of both the embodiment of the methods and the rules and conceptual features of the invention. In these drawings;

[0018] Figure 1 : Schematic view of the relay structure used in the system

[0019] Figure 2: Flow chart of the protection algorithm of adaptive relay References Helping to Understand the Invention

[0020] 1. Input module

[0021] 2. Processor board

[0022] 3. Interface card

[0023] 4. Power supply board

[0024] 5. Communication ports

[0025] 6. Output module

[0026] 7.1 Reading the value

[0027] 7.2 Is there a fault?

[0028] 7.3 Is the adaptive protection active?

[0029] 7.4 Normal protection method

[0030] 7.5 Calculating the intervention time

[0031] 7.6 Sending messages

[0032] 7.7 Has the downtime passed?

[0033] 7.8 Intervene in circuit breakers

[0034] Detailed Description of the Invention

[0035] In this detailed description, the subject of the invention relates to the adaptive digital protection relay and is explained only for the purpose of a better understanding of the subject and in a way that does not create any limiting effect.

[0036] The invention in question consists of:

[0037] • An input module (1) that allows receiving digital and analog signals,

[0038] • A processor card (2) which acts as the main card in the relay and provides inputs,

[0039] • An interface board (3) that allows the user to control, adjust and monitor the status of the relays,

[0040] • A power supply board (4) that powers the relay ,

[0041] • Communication ports (5) that enable digital signals to be transmitted via serial communication protocols and information to be exchanged,

[0042] • An output module (6) that converts signals generated by the microcontroller into a format that can be controlled. The structure of the relay used in the system consists of 5 separate circuit boards and the relay receives its power from the power supply board (4). The processor card (2), which is the main board of the relay, contains the necessary microprocessors and microcontrollers. The processor card, which communicates with the interface card, also receives inputs and sends outputs to the relevant devices from a special output module (6).

[0043] The adaptive protection relays transfer new system changes in a chain by establishing connections between relays. The Adaptive relays makes use of the IEC 61850 GOOSE communication protocol to communicate with other relays via the Ethernet ports in the adaptive relay structure. During this communication, the decision-making mechanism located in the adaptive relays and using the multi-agent system structure provides the opportunity to re-adjust at sufficient speed.

[0044] The multi-agent system structure plays a role in ensuring that the speed of decisions regarding setting changes is not affected by the communication time between relays. The multi-agent system used consists of more than one independent agent. In the system used, the agents are independent pieces of software. Each agent can communicate with other related agents.

[0045] The working method of the multi-agent system structure is that the device agent reads the data received from the physical environment (income, current and status of circuit breakers) and when the intervention decision is made, this agent gives the necessary signal to close the circuit breakers. The communication factor provides communication between the relays. The network and matching agent calculates the short circuit protection settings and load flow protection settings in the light of the data received from the two agents mentioned above and transmits them to the agents. When the protection setting is calculated in the relevant factor, it is sent to the communication factor to be sent to other relays and transferred to the coordination and optimization factor to be applied in the relay. The machine learning algorithms give relays the ability to make opening decisions autonomously and independently. In general, the relay closest to the fault area intervenes in the situation. In addition, if there are spare relays operating in the same direction, they monitor the situation and are activated if the circuit breaker is not opened. If communication is interrupted between relays located in the same direction, the invention uses machine learning software to make the intervention decision independently, as fast as possible in a normal coordinated manner.

[0046] Similarly, if communication between relays in the opposite direction is interrupted, the opening decision is taken quickly and independently using machine learning software.

[0047] Figure 2 is the flow chart of the protection algorithm of the adaptive relay. It shows a common protection mechanism in the multi-agent system used in adaptive relays. Firstly, when a fault occurs, the nearest relay acts according to its own protection function, while the settings of the other relays give the necessary signals to ensure that they act according to the situation.

[0048] The process steps shown in Figure 2 are as follows;

[0049] • current and voltage values are read (7.1 ),

[0050] • is there a fault (values exceeding the limits)? (7.2), if there is no fault, the system automatically continues to read current and voltage values (7.1 ) until it detects a fault. If there is a fault, it is checked whether adaptive protection is active (7.3).

[0051] • if adaptive protection is not active (7.3), the normal protection method (7.4) is applied,

[0052] • the active adaptive protection method (7.3) calculates the intervention time (7.5),

[0053] • the function of sending messages (7.6) sends messages to update the intervention times of other relays,

[0054] • has the downtime passed? (7.7) check is performed, if the downtime has not passed, the value reading (7.1 ) is repeated,

[0055] • If the downtime has passed (7.7), the circuit breakers are intervened (7.8).

[0056] The technical features mentioned in each claim are follows by the reference numbers, which are used only to facilitate the understanding of the claims, therefore it should not be considered that the procedure steps indicated by these reference numbers for the purpose of sampling limit the respective scope.

[0057] It is obvious that a person specialized about the technique may reveal the innovation specified in this invention by means of using similar structures and / or implements this structure in other areas with similar purposes used in the respective technique. Therefore, it is also obvious that such structures would lack of innovation and, in particular, the criterion to exceed the known condition of the technique.

Claims

CLAIMS1. The invention relates to an adaptive digital protection relay and is characterized by;• An input module (1 ) that allows receiving digital and analog signals,• A processor card (2) which acts as the main card in the relay and provides inputs,• An interface board (3) that allows the user to control, adjust and monitor the status of the relays,• A power supply board (4) that powers the relay,• Communication ports (5) that enable digital signals to be transmitted via serial communication protocols and information to be exchanged,• An output module (6) that converts signals generated by the microcontroller into a format that can be controlled.

2. According to the claim 1 , the adaptive digital protection relay relates to the operating method and consists of the following steps:• current and voltage values are read (7.1 ),• is there a fault (values exceeding the limits)? (7.2), if there is no fault, the system automatically continues to read current and voltage values (7.1 ) until it detects a fault. If there is a fault, it is checked whether adaptive protection is active (7.3).• if adaptive protection is not active (7.3), the normal protection method (7.4) is applied,• the active adaptive protection method (7.3) calculates the intervention time (7.5),• the function of sending messages (7.6) sends messages to update the intervention times of other relays,• has the downtime passed? (7.7) check is performed, if the downtime has not passed, the value reading (7.1 ) is repeated,• If the downtime has passed (7.7), the circuit breakers are intervened (7.8).

3. The invention relates to the adaptive digital protection relay and is characterized by that when a change occurs in the electrical network, instead of adjusting all theprotection relays, the protection relay automatically adjusts itself and transfers the new settings to other relays.

4. The invention relates to the adaptive digital protection relay and is characterized by that it is adaptive and facilitates the integration of renewable energy sources and changing loads in the network with the network.

5. The invention relates to an adaptive digital protection relay and is characterized by that it is a robust, fast, autonomous and independent intervention decision against communication interruptions between relays thanks to the machine learning method.

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