Modular air-cooled radiators and their fault early warning methods

Abstract

This invention discloses a modular air-cooled radiator and its fault early warning method. The method first acquires data on the electrophoretic layer thickness, corrosive element concentration, and branch pressure data at the inlet and outlet of each radiator unit. Then, it calculates a corrosion risk coefficient based on the electrophoretic layer thickness and corrosive element concentration data. Next, it calculates the branch pressure deviation based on the branch pressure data and generates a leakage early warning result based on the branch pressure deviation. Finally, it determines the fault level based on the corrosion risk coefficient, the branch pressure data, and the leakage early warning result. This invention can accurately identify the fault location of the air-cooled radiator, improving the accuracy and reliability of fault early warning, thereby ensuring the long-term stable operation of large-capacity offshore wind turbines.

Description

Technical Field

[0001] This invention relates to the field of wind power generation equipment technology, and in particular to a modular air-cooled radiator and its fault early warning method. Background Technology

[0002] The air-cooled radiator of a wind turbine is a core heat dissipation component that ensures the stable operation of the unit. Especially in the highly corrosive environment of the sea with high salt spray, high temperature and high humidity, its heat dissipation performance, corrosion resistance and operational reliability directly determine the heat dissipation efficiency, operational safety and power generation revenue of the wind turbine. At present, traditional wind turbine cooling systems generally adopt an integrated radiator structure, which has many technical defects that are difficult to overcome in practical applications.

[0003] Firstly, traditional radiators are integrated designs. Corrosion, damage, or leakage at any point will quickly cause a drop in pressure throughout the entire cooling system, directly triggering the unit's protective shutdown. This makes it impossible to isolate the faulty unit, severely impacting the continuous operation capability of the wind turbine. Secondly, existing radiators lack anti-corrosion monitoring methods such as electrophoretic layer thickness monitoring and corrosive element detection, making it impossible to identify corrosion trends in advance. Furthermore, relying solely on overall pressure to determine anomalies makes it difficult to distinguish between fluctuations in operating conditions and actual leaks, resulting in delayed warnings and vague location of the problem. For example, among existing air-cooled radiators and their fault warning methods, the combined aluminum plate-fin radiator proposed in Chinese patent CN223815008U only improves heat dissipation efficiency structurally without addressing anti-corrosion monitoring and fault warning functions. Similarly, the plate-fin radiator proposed in Chinese patent CN221147291U only optimizes the heat dissipation structure without adopting a modular design for quick replacement, and also lacks a leak prediction and graded warning mechanism.

[0004] In summary, existing technologies generally suffer from technical problems such as lack of fault isolation capabilities, inability to detect corrosion in advance, susceptibility to false alarms of leaks, inaccurate fault location, and limited early warning methods, making it difficult to ensure the safe operation of large-capacity offshore wind turbines. Summary of the Invention

[0005] The purpose of this invention is to provide a modular air-cooled radiator and its fault early warning method, thereby improving the accuracy and reliability of fault early warning for air-cooled radiators and ensuring the long-term stable operation of large-capacity offshore wind turbines.

[0006] To achieve the above objectives, the present invention provides a fault early warning method for modular air-cooled heat sinks, comprising: Acquire data on the electrophoretic layer thickness, corrosive element concentration, and branch pressure at the inlet and outlet of each heat dissipation unit; The corrosion risk coefficient is calculated based on the electrophoretic layer thickness data and the corrosive element concentration data; Calculate the branch pressure deviation based on the branch pressure data, and generate a leakage early warning result based on the branch pressure deviation; The fault level is determined based on the corrosion risk coefficient, the branch pressure data, and the leakage warning result.

[0007] Optionally, the step of calculating the branch pressure deviation based on the branch pressure data and generating a leakage warning result based on the branch pressure deviation includes: When the pressure deviation of any of the branches exceeds the preset leakage judgment threshold, the main pressure data of the total inlet and outlet of the radiator is obtained; Calculate the main road pressure change value based on the main road pressure data; If the trend of the main road pressure change is consistent with the trend of the branch road pressure deviation and the magnitude of the change is similar, it is determined to be a potential leak. If the trend of the main road pressure change remains stable while the trend of the branch road pressure deviation is abnormal, it is determined to be a branch road leak.

[0008] Optionally, determining the fault level based on the corrosion risk coefficient and the branch pressure deviation includes: If the corrosion risk coefficient is less than the first risk threshold and the branch pressure deviation is less than the first pressure threshold, it is determined to be a general fault level. If the corrosion risk coefficient is greater than or equal to the first risk threshold and less than the second risk threshold, or the branch pressure deviation is greater than or equal to the first pressure threshold and less than the second pressure threshold, then it is determined to be a serious fault level. If the corrosion risk coefficient is greater than or equal to the second risk threshold, or the branch pressure deviation is greater than or equal to the second pressure threshold, then it is determined to be an emergency fault level.

[0009] Optionally, before acquiring the electrophoretic layer thickness data, corrosive element concentration data, and branch pressure data of the liquid inlet and outlet of each heat dissipation unit, the method further includes: The initial electrophoretic layer thickness data of each heat dissipation unit is obtained according to the preset thickness threshold. Obtain the reference values ​​for main road pressure and branch road pressure under fault-free conditions.

[0010] Optionally, the corrosion risk coefficient is determined based on the electrophoretic layer thickness change rate and the concentration of corrosive elements; wherein the electrophoretic layer thickness change rate is calculated based on the electrophoretic layer thickness data and the initial electrophoretic layer thickness data.

[0011] To achieve the above objectives, the present invention also provides a modular air-cooled heat sink, comprising: Multiple heat dissipation units, each of which can be detachably assembled via connecting components; Corrosion monitoring module, which includes an electrophoretic layer thickness unit and a corrosion factor unit; The pressure sensing module includes a main pressure monitoring unit and branch pressure monitoring units. The main pressure monitoring unit is located at the main inlet and outlet of the radiator, and the branch pressure monitoring units are correspondingly located at the inlet and outlet of each of the radiator units. The data processing module is used to execute the fault warning method for the modular air-cooled radiator as described in any of the preceding items.

[0012] Optionally, the electrophoretic layer thickness unit and the corrosion factor unit are disposed at the core, corners and weld positions of each of the heat dissipation units.

[0013] Optionally, the measurement accuracy of the electrophoretic layer thickness unit is ≤1µm, and the detection range of the corrosion factor unit is 0-1000ppm.

[0014] Optionally, the core of the heat dissipation unit is a plate-fin structure.

[0015] Optionally, the modular air-cooled radiator further includes: The remote early warning platform is used to receive fault level information and issue graded early warning instructions.

[0016] Compared with existing technologies, the present invention provides a modular air-cooled radiator and its fault early warning method. This method synchronously collects electrophoretic layer thickness data, corrosive element concentration data, and branch pressure data of each heat dissipation unit. It combines the corrosion risk coefficient and branch pressure deviation to comprehensively judge the leakage early warning result and determine the fault level. This method can effectively solve the problem that local leakage of air-cooled radiators can easily lead to the shutdown of the entire unit. It can realize the early prediction of corrosion risk, accurately identify the fault location of air-cooled radiators, improve the accuracy and reliability of air-cooled radiator fault early warning, and thus ensure the long-term stable operation of large-capacity offshore wind turbines. Attached Figure Description

[0017] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a structural block diagram of a modular air-cooled heat sink; Figure 2This is a flowchart of a fault early warning method for a modular air-cooled radiator provided in an embodiment of the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] See Figure 1 , Figure 1 This is a structural block diagram of a modular air-cooled heat sink provided in an embodiment of the present invention. Figure 1 As shown, the modular air-cooled heat sink includes: Multiple heat dissipation units 1011~101n are provided, and each heat dissipation unit can be detachably assembled via connecting components; Corrosion monitoring module 102, which includes an electrophoretic layer thickness unit 1021 and a corrosion factor unit 1022; The pressure sensing module 103 includes a main pressure monitoring unit 1031 and a branch pressure monitoring unit 1032. The main pressure monitoring unit 1031 is located at the main inlet and outlet of the radiator, and the branch pressure monitoring unit 1032 is located at the inlet and outlet of each of the radiator units. The data processing module 104 is used to execute the fault early warning method for the modular air-cooled heat sink provided in the embodiments of the present invention.

[0021] It should be noted that, to overcome the problems of traditional integrated radiators where partial leakage leads to complete unit shutdown, difficult repair and replacement, and high maintenance costs, this embodiment abandons the traditional integrated structure and disassembles the radiator into several independent modular heat dissipation units. For example, the external dimensions of a single heat dissipation unit are adapted to the lifting requirements of the wind turbine nacelle manhole, allowing for individual access through the manhole and facilitating rapid disassembly and replacement within limited space. The heat dissipation units are sealed together using stainless steel flanges and corrosion-resistant gaskets, forming a complete and sealed heat dissipation path that effectively prevents coolant leakage. Through this structural design, on the one hand, when a heat dissipation unit corrodes or leaks, that unit can be isolated and replaced without affecting the normal operation of other heat dissipation units, fundamentally avoiding the paralysis of the entire radiator due to partial failure; on the other hand, the modular units can be directly lifted through the manhole, significantly shortening the disassembly and assembly time.

[0022] In one alternative embodiment, the core of the heat dissipation unit is a plate-fin structure.

[0023] The plate-fin structure can significantly increase the heat exchange area and improve heat dissipation efficiency within a limited volume. At the same time, the structure is compact and lightweight, making it more suitable for modular design and hoisting requirements. The overall windward area and heat exchange area after splicing are no less than those of traditional integrated radiators, which can ensure that the heat dissipation performance meets the long-term stable operation requirements of large-capacity wind turbine units.

[0024] In one alternative embodiment, the electrophoretic layer thickness unit and the corrosion factor unit are disposed at the core, corners and weld positions of each of the heat dissipation units.

[0025] Specifically, the electrophoretic layer thickness unit is implemented using an electrophoretic layer thickness sensor, and the corrosion factor unit is implemented using a corrosion factor detector. To accurately detect early corrosion risks, the aforementioned sensors and detectors are embedded in key areas such as the core, corners, and welds of the heat dissipation unit. These locations are areas where the heat dissipation equipment is in direct contact with the cooling medium, where structural stress is concentrated, and where corrosion damage is most likely to occur, thus ensuring the authenticity and representativeness of the monitoring data to the greatest extent possible.

[0026] In one optional embodiment, the measurement accuracy of the electrophoretic layer thickness unit is ≤1µm, which can monitor the change in electrophoretic layer thickness in real time and accurately identify early anomalies such as coating thinning and local damage; the detection range of the corrosion factor unit is 0-1000ppm, which can effectively detect the concentration changes of typical corrosive elements such as S and Cl, and provide a basis for judging corrosion trends.

[0027] The above settings enable real-time monitoring of the corrosion status of the heat dissipation unit, allowing for early identification of risks before corrosion develops into a leak. This effectively addresses the lack of corrosion monitoring methods and delayed fault detection in traditional radiators, improving the operational safety and reliability of the heat dissipation system in high-salt-spray and highly corrosive marine environments.

[0028] like Figure 1 As shown, in one optional embodiment, the modular air-cooled radiator further includes: The remote early warning platform 105 is used to receive fault level information and issue graded early warning instructions.

[0029] For example, the remote early warning platform establishes a communication connection with the data processing module via 4G / 5G or WiFi wireless communication. This allows it to receive fault level information uploaded by the data processing module and issue corresponding graded early warning commands according to preset strategies. The remote early warning platform also displays the real-time operating status information of each heat dissipation unit, including key monitoring data such as electrophoretic layer thickness, corrosive element concentration, and fluid pressure. Simultaneously, it can locate the faulty heat dissipation unit based on abnormal data and supports remote control of the opening and closing of corresponding branch valves. Setting up a remote early warning platform can solve the problems of traditional radiator faults being difficult to predict in advance, having unclear fault locations, and being slow to respond on-site. It enables remote, visual monitoring, location, and automatic handling of faults, improving fault response speed.

[0030] In addition, a power supply module 106 can be installed, using DC power and equipped with a backup battery unit, to provide a stable and continuous power supply for the corrosion monitoring module, pressure sensing module, data processing module, and wireless communication module. The purpose is to prevent the monitoring and early warning functions from failing due to a power outage or power fluctuation in the wind turbine's main power supply, and to ensure that the cooling system can operate continuously and stably under any operating conditions.

[0031] See Figure 2 , Figure 2 This is a flowchart of a fault early warning method for a modular air-cooled radiator provided in an embodiment of the present invention. Figure 2 As shown, the fault early warning method for the modular air-cooled heat sink is applied to the data processing module 104, including steps S1 to S4: Step S1: Obtain the electrophoretic layer thickness data, corrosive element concentration data, and branch pressure data of the liquid inlet and outlet of each heat dissipation unit; In one alternative embodiment, prior to step S1, the method further includes: The initial electrophoretic layer thickness data of each heat dissipation unit is obtained according to the preset thickness threshold. Obtain the reference values ​​for main road pressure and branch road pressure under fault-free conditions.

[0032] For example, before the radiator is installed and put into operation, the initial electrophoretic layer thickness data of each heat dissipation unit is collected as d0 through the anti-corrosion monitoring module, and the standard thickness threshold d_std≥20um is set to ensure that the initial anti-corrosion layer meets the anti-corrosion requirements; at the same time, the main pressure reference value Pz0 and the branch pressure reference value Pi0 of the radiator under normal fault-free conditions are collected through the pressure sensing module, and the above initial data are used as the benchmark for data comparison and analysis in subsequent operation.

[0033] It should be noted that the thickness of the electrophoretic layer of the heat dissipation unit and the overall pressure of the heat sink will have initial differences due to variations in assembly, environment, and operating conditions. If theoretical values ​​are used directly as the basis for judgment, it is easy to lead to false alarms or missed alarms. By collecting real initial values ​​and establishing a benchmark, the monitoring errors caused by assembly and environmental differences can be effectively eliminated, making subsequent corrosion risk calculations and pressure deviation judgments more reliable.

[0034] Step S2: Calculate the corrosion risk coefficient based on the electrophoretic layer thickness data and the corrosive element concentration data; In one optional embodiment, the corrosion risk coefficient is determined based on the electrophoretic layer thickness change rate and the concentration of corrosive elements; wherein, the electrophoretic layer thickness change rate is calculated based on the electrophoretic layer thickness data and the initial electrophoretic layer thickness data.

[0035] Specifically, the rate of change of the electrophoretic layer thickness Δd is calculated using the formula: Δd = |d - d0|; Where d is the real-time collected electrophoretic layer thickness data, and d0 is the initial electrophoretic layer thickness data; Further calculate the corrosion rate based on the running time Δt: v = Δd / Δt; Combining the real-time collected concentration of corrosive elements C, the final corrosion risk coefficient is calculated using a corrected formula: K = K0 × (1 + C / C0); In the formula, K0 is the basic corrosion coefficient, which is set to 0.2 in this embodiment based on the material characteristics of the radiator; C0 is the critical value of the concentration of corrosive elements, which is set to 500ppm in this embodiment.

[0036] It should be noted that the corrosion risk coefficient is calculated by combining the thickness change rate, corrosion rate, and corrosive element concentration. This is primarily because offshore wind turbines operate in environments with high salt spray concentrations. Relying solely on coating thickness changes cannot fully reflect corrosion trends. Introducing corrosive element concentration for correction allows for a more accurate and earlier assessment of the corrosion risk level of the heat dissipation unit. This calculation method integrates the coating wear rate with the intensity of environmental corrosion, making corrosion risk assessment more accurate, earlier, and reliable. It enables the identification of potential risks before significant damage to the radiator occurs, effectively improving early warning accuracy and avoiding false alarms or missed alarms caused by relying on a single data point.

[0037] Step S3: Calculate the branch pressure deviation based on the branch pressure data, and generate a leakage early warning result based on the branch pressure deviation; In one optional embodiment, step S3 includes: When the pressure deviation of any of the branches exceeds the preset leakage judgment threshold, the main pressure data of the total inlet and outlet of the radiator is obtained; Calculate the main road pressure change value based on the main road pressure data; If the trend of the main road pressure change is consistent with the trend of the branch road pressure deviation and the magnitude of the change is similar, it is determined to be a potential leak. If the trend of the main road pressure change remains stable while the trend of the branch road pressure deviation is abnormal, it is determined that the branch road is leaking. Specifically, the branch road pressure deviation can be calculated using the following formula: ΔPi = |Pi - P0|; Where Pi is the real-time collected branch pressure data; P0 is the initialized branch pressure baseline value.

[0038] For example, when ΔPi≥10%P0, it is determined to be a potential leak, and a leak warning is not triggered temporarily; When ΔPi ≥ 20% P0, and considering the main road pressure change ΔPz = |Pz Pz0 | Make a comprehensive judgment. If the main pressure change value ΔPz and the branch pressure deviation ΔPi change in the same direction and magnitude over time, then the current pressure fluctuation is determined to be a pressure fluctuation of the entire radiator system, not a branch leak, and is therefore determined to be a potential leak. If the pressure change value ΔPz of the main circuit remains stable without significant fluctuations, while the pressure deviation ΔPi of the branch circuit shows a significant abnormal increase and reaches ΔPi≥20%P0, then the branch circuit is judged to be leaking, that is, the heat dissipation unit of the corresponding branch circuit is leaking.

[0039] It is worth noting that fluctuations in the operating conditions of wind turbines, changes in water temperature, and start-up and shutdown operations can all cause fluctuations in the overall system pressure. If a leak is determined directly based on the pressure deviation of a single branch, false alarms are very likely to occur. However, by comparing the pressure with that of the main branch, the accuracy of leak detection can be improved, avoiding false leak warnings caused by fluctuations in operating conditions and temperature changes. At the same time, it can accurately locate the specific heat dissipation unit branch where the leak occurs, thus improving the reliability of the warning.

[0040] Step S4: Determine the fault level based on the corrosion risk coefficient, the branch pressure data, and the leakage warning result.

[0041] In one optional embodiment, step S4 includes: If the corrosion risk coefficient is less than the first risk threshold and the branch pressure deviation is less than the first pressure threshold, it is determined to be a general fault level. If the corrosion risk coefficient is greater than or equal to the first risk threshold and less than the second risk threshold, or the branch pressure deviation is greater than or equal to the first pressure threshold and less than the second pressure threshold, then it is determined to be a serious fault level. If the corrosion risk coefficient is greater than or equal to the second risk threshold, or the branch pressure deviation is greater than or equal to the second pressure threshold, then it is determined to be an emergency fault level.

[0042] For example, if K < 0.3 and ΔPi < 10%P0, it is judged as a general failure level, that is, there is no obvious risk of corrosion and leakage. If 0.3≤K<0.7 or 10%P0≤ΔPi<20%P0, it is judged as a severe fault level, indicating that there is moderate corrosion or potential leakage. If K ≥ 0.7 or a branch leakage has been identified, it is classified as an emergency fault, indicating severe corrosion or confirmed leakage.

[0043] In one alternative embodiment, the remote early warning platform generates tiered early warning commands based on the fault level. For example, If the fault is of a general level, a yellow warning will be displayed, the data change trend will be recorded, and maintenance personnel will be reminded to conduct follow-up checks every quarter. If the fault is of a serious level, an orange alarm signal will be issued, the corresponding branch current limiting measures will be automatically activated to reduce the risk of fault escalation, and planned maintenance tasks will be pushed. If the fault is an emergency, a red emergency alarm will be issued, the branch valve of the faulty unit will be automatically closed, a rapid sealing command will be triggered, the location information of the faulty unit will be pushed simultaneously, and maintenance personnel will be reminded to replace the failed module within 24 hours.

[0044] In summary, the fault early warning method for modular air-cooled radiators provided by this invention, by simultaneously collecting electrophoretic layer thickness data, corrosive element concentration data, and branch pressure data of each heat dissipation unit, and combining the corrosion risk coefficient and branch pressure deviation to comprehensively judge the leakage early warning result and determine the fault level, can effectively solve the problem that local leakage of air-cooled radiators can easily lead to the shutdown of the entire unit. It can realize the early prediction of corrosion risk, accurately identify the fault location of air-cooled radiators, improve the accuracy and reliability of air-cooled radiator fault early warning, realize the transformation from passive post-event maintenance to proactive pre-event early warning, and thus ensure the long-term stable operation of large-capacity offshore wind turbines.

[0045] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A fault early warning method for a modular air-cooled heat sink, characterized in that, include: Acquire data on the electrophoretic layer thickness, corrosive element concentration, and branch pressure at the inlet and outlet of each heat dissipation unit; The corrosion risk coefficient is calculated based on the electrophoretic layer thickness data and the corrosive element concentration data; Calculate the branch pressure deviation based on the branch pressure data, and generate a leakage early warning result based on the branch pressure deviation; The fault level is determined based on the corrosion risk coefficient, the branch pressure data, and the leakage warning result.

2. The fault early warning method for modular air-cooled heat sinks as described in claim 1, characterized in that, The step of calculating the branch pressure deviation based on the branch pressure data and generating a leakage early warning result based on the branch pressure deviation includes: When the pressure deviation of any of the branches exceeds the preset leakage judgment threshold, the main pressure data of the total inlet and outlet of the radiator is obtained; Calculate the main road pressure change value based on the main road pressure data; If the trend of the main road pressure change is consistent with the trend of the branch road pressure deviation and the magnitude of the change is similar, it is determined to be a potential leak. If the trend of the main road pressure change remains stable while the trend of the branch road pressure deviation is abnormal, it is determined to be a branch road leak.

3. The fault early warning method for modular air-cooled radiators as described in claim 1, characterized in that, The method of determining the fault level based on the corrosion risk coefficient and the branch pressure deviation includes: If the corrosion risk coefficient is less than the first risk threshold and the branch pressure deviation is less than the first pressure threshold, it is determined to be a general fault level. If the corrosion risk coefficient is greater than or equal to the first risk threshold and less than the second risk threshold, or the branch pressure deviation is greater than or equal to the first pressure threshold and less than the second pressure threshold, then it is determined to be a serious fault level. If the corrosion risk coefficient is greater than or equal to the second risk threshold, or the branch pressure deviation is greater than or equal to the second pressure threshold, then it is determined to be an emergency fault level.

4. The fault early warning method for modular air-cooled radiators as described in claim 1, characterized in that, Before acquiring the electrophoretic layer thickness data, corrosive element concentration data, and branch pressure data of the liquid inlet and outlet of each heat dissipation unit, the method further includes: The initial electrophoretic layer thickness data of each heat dissipation unit is obtained according to the preset thickness threshold. Obtain the reference values ​​for main road pressure and branch road pressure under fault-free conditions.

5. The fault early warning method for modular air-cooled radiators as described in claim 4, characterized in that, The corrosion risk coefficient is determined based on the electrophoretic layer thickness change rate and the concentration of corrosive elements; wherein, the electrophoretic layer thickness change rate is calculated based on the electrophoretic layer thickness data and the initial electrophoretic layer thickness data.

6. A modular air-cooled heat sink, characterized in that, include: Multiple heat dissipation units, each of which can be detachably assembled via connecting components; Corrosion monitoring module, which includes an electrophoretic layer thickness unit and a corrosion factor unit; The pressure sensing module includes a main pressure monitoring unit and branch pressure monitoring units. The main pressure monitoring unit is located at the main inlet and outlet of the radiator, and the branch pressure monitoring units are correspondingly located at the inlet and outlet of each of the radiator units. A data processing module is used to execute the fault early warning method for the modular air-cooled radiator as described in any one of claims 1 to 5.

7. The modular air-cooled radiator as described in claim 6, characterized in that, The electrophoretic layer thickness unit and the corrosion factor unit are disposed in the core, corners and weld positions of each of the heat dissipation units.

8. The modular air-cooled radiator as described in claim 7, characterized in that, The measurement accuracy of the electrophoretic layer thickness unit is ≤1µm, and the detection range of the corrosion factor unit is 0-1000ppm.

9. The modular air-cooled radiator as described in claim 6, characterized in that, The core of the heat dissipation unit has a plate-fin structure.

10. The modular air-cooled heat sink as described in claim 6, characterized in that, Also includes: The remote early warning platform is used to receive fault level information and issue graded early warning instructions.

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