Information processing device, evaluation system, and information processing method

Abstract

To accurately evaluate the insulation degradation state of a load system with higher accuracy than conventional methods.SOLUTION: An information processing device (10) is configured to: evaluate the insulation degradation state of a load system (UN) including a load (LD) and a three-phase distribution line (HL) for supplying three-phase AC power to the load (LD); acquire a detection value of AC current flowing through a first phase distribution line (SL1) from a first CT (71), a detection value of AC current flowing through a second phase distribution line (SL2) from a second CT (72), and a detection value of AC current flowing through a third phase distribution line (SL3) from a third CT (73); calculate a zero-phase current flowing through the three-phase distribution line (HL) on the basis of the detected values; calculate an average value of a plurality of estimated values during a first predetermined period; calculate a minimum value from a plurality of average values during a second predetermined period including a plurality of first predetermined periods; calculate a value obtained by subtracting the minimum value from the average value during the first predetermined period as an evaluation target value corresponding to the plurality of estimated values during the first predetermined period; and evaluate the insulation degradation state on the basis of a cumulative value of the time during which the evaluation target value exceeds a current threshold.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] One aspect of the present invention relates to an information processing device that evaluates the state of insulation deterioration of a load system. [Background technology]

[0002] Various techniques have been proposed for monitoring abnormalities in electrical equipment, etc. For example, Patent Document 1 listed below discloses a method for detecting a zero-phase current (referred to as a leakage current in Patent Document 1) in a power distribution line and evaluating the state of insulation deterioration of a load system based on the zero-phase current. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-243787 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of one aspect of the present invention is to evaluate the state of insulation deterioration of a load system with higher accuracy than conventional methods. [Means for solving the problem]

[0005] An information processing device according to one aspect of the present invention is an information processing device for evaluating an insulation deterioration state of a load system including a load and a three-phase distribution line that supplies three-phase AC power to the load, the three-phase distribution line having a first phase distribution line, a second phase distribution line, and a third phase distribution line, the information processing device including a first Current Transducer (CT) that detects a first phase AC current flowing through the first phase distribution line. a first detection value that is a detection value of the first-phase AC current from a transformer (transformer); a second detection value that is a detection value of the second-phase AC current from a second CT that detects the second-phase AC current flowing in the second-phase distribution line; a third detection value that is a detection value of the third-phase AC current from a third CT that detects the third-phase AC current flowing in the third-phase distribution line; an estimate of a zero-phase current flowing in the three-phase distribution line based on the first detection value, the second detection value, and the third detection value; an average value of a plurality of the estimates for a first predetermined period; a minimum value of a plurality of the average values ​​for a second predetermined period that includes a plurality of the first predetermined periods; a value obtained by subtracting the minimum value from the average value for the first predetermined period as an evaluation object value corresponding to the plurality of estimates for the first predetermined period; and an evaluation object value corresponding to the plurality of estimates for the first predetermined period is evaluated based on a cumulative value of the time during which the evaluation object value exceeded a current threshold.

[0006] An information processing method according to one aspect of the present invention is an information processing method for evaluating an insulation deterioration state of a load system including a load and a three-phase distribution line that supplies three-phase AC power to the load, the three-phase distribution line having a first phase distribution line, a second phase distribution line, and a third phase distribution line, the information processing method including: acquiring a first detected value that is a detected value of the first-phase AC current from a second CT that detects the second-phase AC current flowing in the second-phase distribution line; acquiring a second detected value that is a detected value of the second-phase AC current from a third CT that detects the third-phase AC current flowing in the third-phase distribution line; calculating an estimated value of the zero-phase current flowing in the three-phase distribution line based on the first detected value, the second detected value, and the third detected value; calculating an average value of the plurality of estimated values ​​in a first predetermined period; extracting a minimum value from the plurality of average values ​​in a second predetermined period that includes the plurality of first predetermined periods; calculating a value obtained by subtracting the minimum value from the average value in the first predetermined period as an evaluation object value corresponding to the plurality of estimated values ​​in the first predetermined period; and evaluating the insulation degradation state based on a cumulative value of the time during which the evaluation object value exceeds a current threshold. [Effects of the Invention]

[0007] According to one aspect of the present invention, the state of insulation deterioration of a load system can be evaluated with higher accuracy than conventional methods. [Brief explanation of the drawings]

[0008] [Figure 1] 1 shows an example of the configuration of an evaluation system and its peripherals in the first embodiment. [Figure 2] An example of the time progression of Io' in a healthy case is shown below. [Figure 3] An example of the time transition of Io'_av in a healthy case is shown below. [Figure 4] An example of the time progression of ΔIo'_av in a healthy case is shown below. [Figure 5] An example of the time progression of Io' in an accident precursor case is shown below. [Figure 6] An example of the time transition of Io'_av in an accident precursor case is shown below. [Figure 7] An example of the time transition of ΔIo'_av in an accident precursor case is shown below. [Figure 8] 10 shows an example of the time transition of the first cumulative value in a healthy case. [Figure 9] 10 shows an example of the time transition of the second cumulative value in a healthy case. [Figure 10] An example of the time transition of the third cumulative value in a healthy case is shown. [Figure 11] 10 shows an example of the time transition of the first cumulative value in an accident precursor case. [Figure 12] 10 shows an example of the time transition of the second cumulative value in an accident precursor case. [Figure 13] 10 shows an example of the time transition of the third cumulative value in an accident precursor case. [Figure 14] An example of the time progression of the risk level in a healthy case is shown below. [Figure 15] An example of the time progression of danger levels in an accident precursor case is shown below. DETAILED DESCRIPTION OF THE INVENTION

[0009] [Embodiment 1] Embodiment 1 will be described below. For convenience of explanation, components having the same functions as those described in Embodiment 1 will be denoted by the same reference numerals in the following embodiments, and their description will not be repeated. For simplicity, descriptions of well-known technical matters will be omitted as appropriate. Unless otherwise specified, the components and numerical values ​​described in this disclosure are merely examples. Therefore, for example, unless otherwise specified, the positional and connection relationships of the components are not limited to the examples in the figures.

[0010] FIG. 1 illustrates an example of an evaluation system 1 and its peripheral configuration in embodiment 1. The evaluation system 1 includes an information processing device 10. In the example of FIG. 1, the information processing device 10 is located inside electrical equipment EE. In FIG. 1, a power distribution facility is exemplified as the electrical equipment EE. In the example of FIG. 1, a load LD is located outside the electrical equipment EE.

[0011] In the example of Fig. 1, a three-phase AC power system PL is located upstream of the electrical equipment EE. The electrical equipment EE in Fig. 1 has a transformer TR. The primary side of the transformer TR is connected to the power system PL, and the secondary side of the transformer TR is connected to the power distribution system of the electrical equipment EE.

[0012] 1 transforms the high voltage (e.g., 6000 V) of the power system PL into a lower voltage (e.g., 200 V) suitable for the load LD. In this way, the transformer TR supplies the low voltage to the load LD.

[0013] 1, N loads LD are illustrated. N may be any natural number. In the first embodiment, a case where there are a plurality of loads LD, that is, N is 2 or more, is illustrated.

[0014] In this specification, when distinguishing between N loads LD, the i-th load LD is denoted as load LD-i, where i is any natural number greater than or equal to 1 and less than or equal to N. Therefore, in Fig. 1, load LD-1 refers to the first load LD, and load LD-N refers to the N-th load LD. This notation for the load LD also applies to other components corresponding to the load LD.

[0015] 1 , a three-phase distribution line HL supplies three-phase AC power to a load LD. The three-phase distribution line HL is drawn from a power distribution system in an electrical installation EE. In the first embodiment, a component including the load LD and the three-phase distribution line HL corresponding to the load is referred to as a load system UN. The load system UN may also be referred to as a load unit. In the example of FIG. 1 , N load systems are illustrated.

[0016] The three-phase distribution line HL includes a first phase distribution line SL1, a second phase distribution line SL2, and a third phase distribution line SL3. For example, the first phase is U-phase, the second phase is V-phase, and the third phase is W-phase.

[0017] The evaluation system 1 has a CT set 70 including a first CT 71, a second CT 72, and a third CT 73. In the example of Fig. 1, one CT is provided corresponding to a certain distribution line in order to detect the AC current flowing through that distribution line of that phase.

[0018] Specifically, in the example of FIG. 1, the first CT 71 detects a first-phase AC current (e.g., a U-phase AC current) flowing through the first-phase distribution line SL1. The first-phase distribution line SL1 passes through the first CT 71 and is connected to the load LD. Therefore, the first-phase AC current can be detected by the first CT 71. In this specification, the detected value of the first-phase AC current is referred to as a first detected value. The information processing device 10 acquires the first detected value from the first CT 71.

[0019] The second CT 72 detects a second-phase AC current (e.g., a V-phase AC current) flowing through the second-phase distribution line SL2. The second-phase distribution line SL2 passes through the second CT 72 and is connected to the load LD. Therefore, the second-phase AC current can be detected by the second CT 72. In this specification, the detected value of the second-phase AC current is referred to as a second detected value. The information processing device 10 acquires the second detected value from the second CT 72.

[0020] The third CT 73 detects a third-phase AC current (e.g., a W-phase AC current) flowing through the third-phase distribution line SL3. The third-phase distribution line SL3 passes through the third CT 73 and is connected to the load LD. Therefore, the third CT 73 can detect the third-phase AC current. In this specification, the detected value of the third-phase AC current is referred to as a third detected value. The information processing device 10 acquires the third detected value from the third CT 73.

[0021] The information processing device 10 evaluates the insulation deterioration state of the load system UN. The information processing device 10 in the first embodiment evaluates the insulation deterioration state of the load system UN based on the first to third detection values ​​acquired from the CT set 70.

[0022] As is known to those skilled in the art, when there is an imbalance between the first-phase AC current, the second-phase AC current, and the third-phase AC current, a zero-phase current flows in the three-phase distribution line HL. For this reason, the zero-phase current is used as an evaluation index for the insulation deterioration state of the three-phase distribution line HL. As an example, when the three-phase distribution line HL deteriorates over time, the zero-phase current increases due to the insulation deterioration of the three-phase distribution line HL. As another example, when the three-phase distribution line HL suffers mechanical damage, the zero-phase current increases due to damage to the insulating members of the three-phase distribution line HL.

[0023] As another example, even if the three-phase distribution line HL is healthy, the zero-phase current flowing through the three-phase distribution line HL may increase due to aging or an abnormality (e.g., an accident) in the load LD connected to the three-phase distribution line HL. Therefore, the zero-phase current can also be used as an evaluation index for the insulation deterioration state of the load LD.

[0024] For this reason, ZCTs (Zero Current Transformers) that detect the zero-phase current flowing in three-phase distribution lines are sometimes installed in electrical equipment. However, ZCTs are larger devices than CTs, and therefore require a large space for installation.

[0025] Therefore, due to space constraints on the electrical equipment, it may be difficult or impossible to install a ZCT in that equipment. For example, in electrical equipment where the installation of a ZCT was not originally intended, there may be little space around the three-phase distribution lines to install additional equipment, making it impossible to install a new ZCT.

[0026] With this in mind, Fig. 1 illustrates an evaluation system 1 that includes a CT set 70 instead of a ZCT. Because a CT is a smaller device than a ZCT, installing the CT set 70 does not require as much space as installing a ZCT. Therefore, the evaluation system 1 is suitable for electrical equipment EE, where the installation space for equipment is limited.

[0027] As described above, the zero-phase current flowing through the three-phase distribution line HL is one of the evaluation indexes for the insulation deterioration state of the load LD. Therefore, the information processing device 10 calculates an estimate of the zero-phase current flowing through the three-phase distribution line HL based on the first, second, and third detected values. The zero-phase current is generally represented as Io. Therefore, in this specification, the estimate of the zero-phase current is represented as Io'.

[0028] The information processing device 10 acquires the first to third detected values ​​to be used for calculating Io' in a certain three-phase distribution line HL from the CT set 70 corresponding to the three-phase distribution line HL. In the example of Fig. 1, one CT set 70 is located so as to correspond to one load LD. Therefore, the evaluation system 1 has N CT sets 70.

[0029] According to the configuration of Fig. 1, the zero-phase current flowing through a certain three-phase distribution line HL is equivalent to the zero-phase current flowing through the load system UN corresponding to the three-phase distribution line HL. Therefore, the information processing device 10 in the first embodiment evaluates the insulation deterioration state of the load system UN based on Io'. In this specification, the estimated value of the zero-phase current flowing through the three-phase distribution line HL-i is denoted as Io'(i). The information processing device 10 evaluates the insulation deterioration state of the load system UN-i based on Io'(i).

[0030] According to the configuration of the first embodiment, the insulation deterioration states of N load systems UN can be individually evaluated by one information processing device 10. For convenience of explanation, the following mainly describes an example of processing in which the information processing device 10 evaluates the insulation deterioration state of one load system UN (e.g., load system UN-1).

[0031] The information processing device 10 in the example of FIG. 1 includes a data processing unit 11 and an evaluation unit 12. The data processing unit 11 acquires the first to third detection values ​​from the CT set 70 and generates time-series data of the first to third detection values. The time period during which the data processing unit 11 acquires the first to third detection values ​​from the CT set 70 may be any period. As an example, the data processing unit 11 acquires the first to third detection values ​​from the CT set 70 every second.

[0032] The data processing unit 11 calculates Io' at each time point based on the first to third detection values ​​at each time point. In this way, the data processing unit 11 generates time-series data of Io' based on the first to third detection values. Any method can be used to calculate Io'. As an example, the data processing unit 11 calculates Io' through a series of vector operations based on the first to third detection values.

[0033] Generally, the zero-phase current often contains noise components. Therefore, the time-series data of Io' is also expected to contain significant noise components. Therefore, the data processing unit 11 may derive an evaluation object value corresponding to Io' by performing data processing to remove the noise components from Io'.

[0034] Averaging time-series data is an example of a process for removing noise components from the time-series data. Therefore, as an example, the data processing unit 11 may calculate an average value of multiple Io' values ​​in a first predetermined period as an evaluation target value corresponding to the multiple Io' values ​​in the first predetermined period. The first predetermined period may be set arbitrarily as long as it is a length of time considered suitable for noise removal. In the first embodiment, the length of the first predetermined period is set to three days. The first predetermined period may also be referred to as an average calculation period.

[0035] In this specification, the average value of Io' for the first predetermined period is referred to as Io'_av. The data processing unit 11 calculates Io'_av for each first predetermined period. Therefore, the data processing unit 11 generates time-series data of the three-day moving average of Io'_av.

[0036] Since Io' is an estimated value, it often contains noise components derived from the calculation process of the estimated value. In order to remove these noise components, it is considered preferable that the length of the first predetermined period is not too short.

[0037] In general, it is considered that changes in the operating state of the load LD have a daily periodicity. For this reason, it is preferable that the length of the first predetermined period is one day or more. By setting the length of the first predetermined period to one day or more, it is possible to obtain Io'_av that reflects the daily periodicity. In addition, it is also possible to effectively remove noise components derived from the calculation process of the estimated value itself.

[0038] On the other hand, if the length of the first predetermined period is set too long, there is a risk that the temporary change trend of Io' will be canceled out by the averaging process. Therefore, as an example, it is preferable to set the length of the first predetermined period to be slightly shorter than 7 days (1 week). According to the study by the inventors of the present application, it is preferable that the length of the first predetermined period is 5 days or less. For the above reasons, it is preferable that the length of the first predetermined period is 1 day or more and 5 days or less.

[0039] When the load system UN is healthy, the actual value of the zero-phase current flowing through the three-phase distribution line HL is approximately 0. On the other hand, as described above, Io' often contains noise components resulting from the calculation process of the estimated value. For this reason, even when the load system UN is healthy, Io'_av may be significantly larger than 0 (see, for example, Figure 3 below).

[0040] In this way, Io'_av may contain an offset value as a noise component. Therefore, it is considered more preferable to use the signal value obtained after removing the offset value from Io'_av as the evaluation target value.

[0041] As an example, the offset value of Io'_av may be represented by the minimum value of multiple Io'_av values ​​in a certain period. Therefore, in the first embodiment, the data processing unit 11 extracts the minimum value from multiple Io'_av values ​​in a second predetermined period that includes multiple first predetermined periods.

[0042] In embodiment 1, the length of the second predetermined period is set to 45 days. Therefore, the second predetermined period in embodiment 1 includes 15 first predetermined periods. The second predetermined period may be referred to as a minimum value extraction period.

[0043] In this specification, the minimum value of Io'_av in the second predetermined period is denoted as Io'_avmin. As is clear from the above explanations, the zero-phase current flowing in the three-phase distribution line HL can increase with the passage of time.

[0044] For this reason, it is preferable that the start point of the second predetermined period be positioned as early as possible in the measurement period described below. In the first embodiment, the start point of the second predetermined period coincides with the start point of the measurement period (see, for example, FIG. 3). Therefore, the end point of the second predetermined period in the first embodiment is 45 days after the start point of the measurement period. The data processing unit 11 extracts Io'_avmin from among multiple Io'_av from the start point of the measurement period up to 45 days after the start point.

[0045] In order to obtain an appropriate Io'_avmin as a representative value of the Io'_av offset value, it is preferable that the second predetermined period be set to be somewhat longer than the first period. According to studies by the inventors of the present application, an appropriate Io'_avmin can be obtained by extracting Io'_avmin from multiple Io'_av values ​​over a period of approximately one to three months. For this reason, it is preferable that the length of the second predetermined period be set to be 30 days or more and 90 days or less, for example.

[0046] Next, the data processing unit 11 may derive an evaluation object value based on Io'_av and Io'_avmin. In the first embodiment, the data processing unit 11 calculates, for a certain first predetermined period, a value obtained by subtracting Io'_avmin from Io'_av for the first predetermined period, as the evaluation object value corresponding to the plurality of Io's for the first predetermined period.

[0047] In this specification, the value obtained by subtracting Io'_avmin from Io'_av is represented as ΔIo'_av. In the first embodiment, the data processing unit 11 calculates ΔIo'_av for each first predetermined period. Therefore, the data processing unit 11 generates time-series data of ΔIo'_av every three days.

[0048] That is, the data processing unit 11 calculates the following equation (1): ΔIo'_av=Io'_av-Io'_avmin …(1) Generate three-day time series data of ΔIo'_av given by

[0049] ΔIo'_av given by equation (1) is an example of a signal value after removing the offset value from Io'_av. For this reason, ΔIo'_av is considered to be a signal value that is closer to the actual Io than Io'_av.

[0050] Therefore, ΔIo'_av is considered to be closer to the time average value of the actual Io than Io'_av. Therefore, by using ΔIo'_av as the evaluation target value, it is expected that the insulation deterioration state of the load system UN can be more appropriately evaluated than when Io'_av is used as the evaluation target value. Therefore, in the first embodiment, a case where the evaluation unit 12 evaluates the insulation deterioration state of the load system UN based on ΔIo'_av is illustrated.

[0051] In the first embodiment, it is assumed that one or more current thresholds are set for the evaluation target value. In this specification, the total number of current thresholds is denoted as M. M may be any natural number. Among the M current thresholds, the j-th current threshold is denoted as the j-th current threshold. j is any natural number greater than or equal to 1 and less than or equal to M.

[0052] In the first embodiment, a case where M is 2 or more is exemplified. That is, a case where multiple current thresholds are set for the evaluation target value is exemplified. In the first embodiment, for any j, the (j+1)th current threshold is set to a value greater than the jth current threshold. That is, as the current threshold number j increases, the current threshold corresponding to that number increases. In this way, the (j+1)th current threshold is associated with insulation deterioration that is more serious than the jth current threshold.

[0053] In the first embodiment, as an example, a case where M=3 will be described. That is, a case where three individual current thresholds, from a first current threshold to a third current threshold, are set will be described. The first current threshold is the minimum current threshold. The second current threshold is the current threshold next largest after the first current threshold. The third current threshold is the current threshold next largest after the second current threshold. The third current threshold in the first embodiment is the maximum current threshold. Therefore, the second current threshold in the first embodiment is an intermediate current threshold.

[0054] According to the findings of the inventors of the present application, when the zero-phase current is about 50 mA or less, the risk of an accident caused by insulation deterioration of the load system UN is considered to be relatively low. On the other hand, when the zero-phase current reaches about 100 mA or more, the risk of an accident caused by insulation deterioration of the load system UN is considered to be somewhat high. In addition, when the zero-phase current reaches about 200 mA or more, the risk of an accident caused by insulation deterioration of the load system UN is considered to be quite high.

[0055] Therefore, each of the M current thresholds in embodiment 1 may be set based on the above findings. As an example, the first current threshold may be 20 mA to 60 mA, the second current threshold may be 60 mA to 120 mA, and the third current threshold may be 120 mA to 300 mA. In embodiment 1, a case where the first current threshold is 50 mA, the second current threshold is 100 mA, and the third current threshold is 200 mA is exemplified.

[0056] By considering not only the evaluation target value but also the length of time during which a relatively large value of the evaluation target value has occurred, the insulation deterioration state of the load system UN can be evaluated in more detail. Therefore, in the first embodiment, the evaluation unit 12 evaluates the insulation deterioration state of the load system UN based on the cumulative value of the time during which the evaluation target value has exceeded the current threshold.

[0057] It is preferable that the evaluation result of the insulation degradation state of the load system UN be presented to the manager of the load system UN as data that is easy for the manager to understand. Therefore, in the first embodiment, the evaluation unit 12 sets a danger level that indicates the evaluation result of the insulation degradation state of the load system UN based on the evaluation target value and the cumulative value of the time during which the evaluation target value exceeds the current threshold. In the first embodiment, the evaluation unit 12 sets the danger level as a discrete value.

[0058] The danger level may be used as an index representing the likelihood (risk) of an accident occurring in the load system UN due to insulation deterioration of the load system UN. As an example, the evaluation unit 12 may output the danger level to a display device (not shown) and cause the display device to display the danger level. This allows the danger level to be visually presented to the manager of the load system UN. The display device may be an internal component of the information processing device 10 or an external component of the information processing device 10.

[0059] To manually evaluate the insulation deterioration state of the load system UN from the time trend of the evaluation target value itself requires specialized knowledge about the load system UN. Therefore, by presenting the risk level, which is the evaluation result of the evaluation unit 12, to the manager as a discrete value, even a manager with little specialized knowledge can easily understand the insulation deterioration state of the load system UN. As a result, for example, the manager can plan maintenance of the load system UN according to the presented risk level.

[0060] In the first embodiment, it is assumed that multiple risk levels can be assigned. In this specification, the total number of risk levels is denoted as L. L may be any natural number equal to or greater than 2. Of the L risk levels, the kth risk level is denoted as the kth level. The kth level may also be denoted as level k. k is a number representing the risk level. k is any natural number equal to or greater than 0 and equal to or less than L-1.

[0061] In the first embodiment, for any k, the (k+1)th level is associated with insulation deterioration that is more serious than the kth level. From this, it can be said that the higher the danger level, the higher the possibility of an accident occurring in the load system UN due to insulation deterioration.

[0062] In the first embodiment, a case where L=4 is exemplified. That is, in the first embodiment, a case where four individual risk levels, from level 0 to level 3, can be assigned is exemplified. Level 0, which is the lowest (minimum) value of the risk levels, is also referred to as the lowest level. Level 0 may also be referred to as the safety level. In the first embodiment, the initial value of the risk level is set to level 0.

[0063] The first level is the next highest danger level after the zeroth level. The second level is the next highest danger level after the first level. The third level is the next highest danger level after the second level. The third level in embodiment 1 is the highest (maximum) danger level. Therefore, the first and second levels in embodiment 1 are intermediate danger levels.

[0064] In the first embodiment, there are cases where both the conditions for setting a certain risk level and the conditions for setting a lower risk level are satisfied. In this case, the evaluation unit 12 performs a determination process by preferentially adopting the conditions for setting a higher risk level, and sets the risk level.

[0065] As an example, even if an evaluation target value exceeds the first current threshold (e.g., 50 mA) described above, if the time period during which the evaluation target value exceeds the first current threshold is relatively short, it is considered that no significant insulation deterioration has yet occurred in the load system UN. Therefore, the evaluation unit 12 calculates the cumulative value of the time during which the evaluation target value exceeds the first current threshold. In this specification, this cumulative value is referred to as the first cumulative value.

[0066] Then, when the first cumulative value is less than the first time threshold, the evaluation unit 12 sets the risk level to Level 0. As an example, the first time threshold may be 1 hour (hr) to 10 hours. In the first embodiment, a case where the first time threshold is 5 hours is illustrated. Therefore, the evaluation unit 12 maintains the risk level at Level 0 until the first cumulative value reaches 5 hours.

[0067] Even if the first cumulative value exceeds the first time threshold, if the first cumulative value is not so large, it is considered that the insulation deterioration of the load system UN is minor. For this reason, in the first embodiment, the evaluation unit 12 increases the danger level to the first level when the first cumulative value is equal to or greater than the first time threshold and less than the second time threshold. Less than the second time threshold may be set to a value greater than the first time threshold. As an example, the second time threshold may be 50 hours to 200 hours. In the first embodiment, a case where the second time threshold is 100 hours is exemplified.

[0068] On the other hand, when the first cumulative value reaches the second time threshold, it is considered that a certain degree of insulation deterioration has occurred in the load system UN. For this reason, in the first embodiment, when the first cumulative value is equal to or greater than the second time threshold, the evaluation unit 12 increases the danger level to the second level.

[0069] Furthermore, when the evaluation target value exceeds the second current threshold (e.g., 100 mA), it is considered that some degree of insulation deterioration has occurred in the load system UN. For this reason, in the first embodiment, the evaluation unit 12 increases the danger level to the second level when the evaluation target value exceeds the second current threshold.

[0070] If the time during which the evaluation target value exceeds the second current threshold becomes long to some extent, it is considered that more serious insulation deterioration has occurred in the load system UN. Therefore, the evaluation unit 12 calculates the cumulative value of the time during which the evaluation target value exceeds the second current threshold. In this specification, this cumulative value is referred to as the second cumulative value. In the first embodiment, if the second cumulative value is equal to or greater than the third time threshold, the evaluation unit 12 increases the danger level to the third level. As an example, the third time threshold may be 1 hour to 10 hours. In the first embodiment, a case where the third time threshold is 5 hours is illustrated.

[0071] Furthermore, when the evaluation target value exceeds the above-mentioned third current threshold (e.g., 200 mA), it is considered that more serious insulation deterioration has occurred in the load system UN. For this reason, in the first embodiment, the evaluation unit 12 increases the danger level to the third level when the evaluation target value exceeds the third current threshold.

[0072] The evaluation unit 12 may calculate a cumulative value of the time during which the evaluation target value exceeds a third current threshold. In this specification, this cumulative value is referred to as a third cumulative value. If a risk level higher than the third level can be assigned, the condition for setting the risk level may be associated with the third cumulative value.

[0073] As described above, the evaluation unit 12 may set a danger level based on which of a plurality of current thresholds the evaluation target value has exceeded and for how long.

[0074] (Examples of healthy cases and accident precursor cases) 2 to 15 show examples of time transitions of various data in the first embodiment. Examples of evaluation results by the information processing device 10 will be described with reference to these figures. In the electrical equipment EE of this example, first to third detection values ​​are detected by the CT set 70 over a measurement period from a certain day in early February to May 31 of a certain year. Then, in this example, the information processing device 10 derives each piece of data based on the first to third detection values ​​and performs evaluation based on the data.

[0075] 2 to 4 show examples of time transitions of each current value obtained in a healthy load system UN. In this example, a healthy load system UN refers to a load system UN whose risk score did not increase from 0 throughout the entire measurement period. In this specification, cases related to a healthy load system UN are also referred to as "healthy cases."

[0076] Fig. 2 shows an example of the time course of Io' in a healthy case, Fig. 3 shows an example of the time course of Io'_av in a healthy case, and Fig. 4 shows an example of the time course of ΔIo'_av in a healthy case. Each current value in the examples of Figs. 2 to 4 is derived by the data processing unit 11. The symbol SP in Fig. 3 and Fig. 6 described below represents the above-mentioned second predetermined period.

[0077] In the example of Fig. 3, the minimum value of Io'_av during the measurement period is significantly greater than 0. On the other hand, in the example of Fig. 4, the minimum value of ΔIo'_av during the measurement period is approximately 0. From this, it can be said that ΔIo'_av in the example of Fig. 4 is a suitable example of an evaluation target value. In Fig. 4 and Fig. 7 described below, symbol TH1 represents the first current threshold, symbol TH2 represents the second current threshold, and symbol TH3 represents the third current threshold.

[0078] 5 to 7 show examples of time transitions of each current value obtained in an unhealthy load system UN. FIGS. 5 to 7 are diagrams paired with FIGS. 2 to 4, respectively. In this example, an unhealthy load system UN refers to a load system UN whose risk score increased from 0 during the measurement period. As can be understood from the above explanations, an increase in the risk score can be said to be a sign of an accident occurring in the load system UN. Therefore, in this specification, cases related to an unhealthy load system UN are also referred to as "accident sign cases."

[0079] Fig. 5 shows an example of the time course of Io' in an accident precursor case, Fig. 6 shows an example of the time course of Io'_av in an accident precursor case, and Fig. 7 shows an example of the time course of ΔIo'_av in an accident precursor case. Each current value in the examples of Figs. 5 to 7 is derived by data processing unit 11.

[0080] In this specification, an accident refers to an event that causes an evaluation target value to exceed a predetermined reference value. The predetermined reference value may be, for example, an evaluation target value (e.g., 1000 mA) corresponding to a current value that causes an operation of a protective device (e.g., a breaker, not shown). The protective circuit may be located on a three-phase distribution line HL. For example, if a ground fault or short circuit occurs in the three-phase distribution line HL, an evaluation target value that exceeds the reference value may occur. If a ground fault or short circuit occurs in the load LD, an evaluation target value that exceeds the reference value may also occur.

[0081] In the example of Fig. 6, the minimum value of Io'_av during the measurement period is significantly greater than 0. On the other hand, in the example of Fig. 7, the minimum value of ΔIo'_av during the measurement period is approximately 0. For this reason, it can be said that ΔIo'_av in the example of Fig. 7 is also a suitable example of an evaluation target value.

[0082] 8 to 10 show examples of the time transition of each cumulative value in healthy cases. Meanwhile, FIGS. 11 to 13 show examples of the time transition of each cumulative value in accident precursor cases. FIGS. 11 to 13 are diagrams that are paired with FIGS. 8 to 10, respectively. The cumulative values ​​at each time point in the examples of FIGS. 8 to 13 are derived by the evaluation unit 12.

[0083] FIG. 8 shows an example of the time progression of the first cumulative value in a healthy case, FIG. 9 shows an example of the time progression of the second cumulative value in a healthy case, and FIG. 10 shows an example of the time progression of the third cumulative value in a healthy case.

[0084] As shown in Figure 2 above, in the healthy case, Io' is quite small throughout the entire measurement period. Therefore, as shown in Figure 3, in the healthy case, Io'_av is also quite small throughout the entire measurement period. Therefore, as shown in Figure 4, in the healthy case, ΔIo'_av, which is the value to be evaluated, is also quite small throughout the entire measurement period.

[0085] As shown in Fig. 4, in the healthy case, ΔIo'_av is below the first current threshold TH1 throughout the entire measurement period. Therefore, as shown in Figs. 8 to 10, in the healthy case, the first cumulative count to the third cumulative count are all 0 throughout the entire measurement period.

[0086] Next, reference will be made to Figures 11 to 13. Figure 11 shows an example of the time transition of the first cumulative value in an accident precursor case, Figure 12 shows an example of the time transition of the second cumulative value in an accident precursor case, and Figure 13 shows an example of the time transition of the third cumulative value in an accident precursor case.

[0087] As shown in Figure 5 above, in the accident premonition cases, Io' tends to increase as time passes from the start of the measurement period. For this reason, as shown in Figure 6, in the accident premonition cases, Io'_av also tends to increase as time passes. Therefore, as shown in Figure 7, in the accident premonition cases, the evaluation target value ΔIo'_av also tends to increase as time passes. Furthermore, unlike the healthy cases, the accident premonition cases have many peaks in ΔIo'_av.

[0088] Furthermore, as shown in Figure 5, in the accident precursor case, a significantly large peak in Io' occurred for the first time around April 2. The peaks in Io'_av and ΔIo'_av around April 2, shown in Figures 6 and 7, respectively, correspond to the above peaks in Io'.

[0089] In the example of FIG. 5, no accidents occurred during the entire measurement period. However, the peak around April 2 in the examples of FIGS. 5 to 7 is considered to be one of the signs of a future accident. Therefore, in the accident sign case, it is considered that there is a high possibility of an accident occurring after the measurement period. The information processing device 10 can present a risk level according to the above-mentioned signs to the manager of the load system UN. Therefore, the information processing device 10 contributes to preventing accidents from occurring in the load system UN.

[0090] As shown in Figure 7, in the accident precursor cases, ΔIo'_av exceeding the first current threshold TH1 frequently occurred during the measurement period. As a result, as shown in Figure 11, in the accident precursor cases, the final first cumulative value exceeded 1000 hours. In this way, in the accident precursor cases, first cumulative values ​​exceeding the above-mentioned first time threshold and second time threshold were obtained.

[0091] In the accident precursor cases, there were many instances of ΔIo'_av exceeding the second current threshold TH2 during the measurement period. As a result, as shown in Figure 12, in the accident precursor cases, the final second cumulative value also exceeded 1000 hours. In this way, in the accident cases, a second cumulative value exceeding the above-mentioned third time threshold was obtained.

[0092] In the accident precursor cases, there were many occurrences of ΔIo'_av exceeding the third current threshold TH3 during the measurement period. As a result, as shown in Figure 13, in the accident precursor cases, the final third cumulative value also exceeded 1000 hours.

[0093] FIG. 14 shows an example of the time transition of the danger level in a healthy case. On the other hand, FIG. 15 shows an example of the time transition of the danger level in an accident case. FIG. 15 is a diagram paired with FIG. 14. The vertical axis of the graphs in FIGS. 14 to 15 indicates the value of the danger level. The danger level at each time point in the examples of FIGS. 14 to 15 is set by the evaluation unit 12.

[0094] As shown in Fig. 4 above, in the healthy case, ΔIo'_av is below the first current threshold TH1 throughout the entire measurement period. Therefore, as shown in Fig. 14, in the healthy case, the danger level remains at level 0 throughout the entire measurement period.

[0095] On the other hand, as shown in Figure 7 above, in the accident premonition cases, ΔIo'_av tends to increase over time. Therefore, in the accident premonition cases, the danger level increases over time. As can be seen from Figure 7, in the accident premonition cases, the first cumulative count reached 4 shortly before April 2nd. Therefore, in Figure 15, the danger level increased from level 0 to level 1 at that time.

[0096] Next, in the accident sign case, ΔIo'_av that exceeds the second current threshold TH2 occurs immediately after the danger level increases to Level 1. Therefore, in Figure 15, the danger level increases from Level 1 to Level 2 at that time.

[0097] Next, in the accident precursor case, ΔIo'_av, which exceeds the third current threshold TH3, occurs immediately after the danger level increases to level 2. Therefore, in Figure 15, the danger level increases from level 2 to level 3 at that time. Thereafter, the danger level is maintained at level 3.

[0098] (effect) As described above, the technology of Patent Document 1 evaluates the insulation deterioration state of a load system based on the zero-phase current of a distribution line. However, the zero-phase current may be affected by weather conditions (e.g., temperature, humidity, and whether or not there is precipitation). The zero-phase current may also be affected by the contamination state of the load system. For this reason, the zero-phase current does not necessarily have a high correlation with the insulation deterioration state of the load system.

[0099] Therefore, the technology of Patent Document 1 cannot necessarily evaluate the insulation deterioration state of the load system with high accuracy. In particular, the technology of Patent Document 1 is likely to reduce evaluation accuracy when the load system is located outdoors. This is because when the load system is located outdoors, the load system is more susceptible to weather conditions and is more likely to become contaminated than when the load system is located indoors.

[0100] Meanwhile, the evaluation system 1 (particularly, the information processing device 10) calculates the above-mentioned ΔIo'_av as the evaluation target value. Then, the information processing device 10 evaluates the insulation degradation state of the load system based on ΔIo'_av. For example, the information processing device 10 evaluates the insulation degradation state based on the cumulative value of the time during which ΔIo'_av exceeds the current threshold.

[0101] As is clear from the above explanations, ΔIo'_av is a signal with less noise than Io', which is an estimated value of the zero-phase current flowing through the three-phase distribution line HL. In addition, ΔIo'_av is a signal with less noise than Io'_av, which is the average value of Io'. Therefore, it can be said that ΔIo'_av is a signal in which the influence of noise components contained in Io' is effectively reduced. For this reason, by using ΔIo'_av as the evaluation target value, the state of insulation deterioration of the load system can be evaluated with higher accuracy. As described above, the information processing device 10 can evaluate the state of insulation deterioration of the load system with higher accuracy than the technology of Patent Document 1.

[0102] The technology itself for detecting some kind of abnormality based on the zero-phase current is well known. In the known technology, it is generally determined that an abnormality has occurred when the zero-phase current measured by, for example, a ZCT exceeds a threshold value. In the known technology, to improve the accuracy of determining the occurrence of an abnormality, it is generally necessary to additionally measure electrical quantities other than the zero-phase current (e.g., zero-phase voltage or power supply voltage).

[0103] In contrast, the information processing device 10 derives Io' based on the first to third detection values ​​acquired from the CT set 70. That is, the evaluation system 1 does not require a ZCT that detects the zero-phase current flowing in the three-phase distribution line HL. In addition, the information processing device 10 can evaluate the insulation deterioration state of the load system based on Io' without requiring any further measurement of the above-mentioned electrical quantity.

[0104] In this way, the evaluation system 1 can evaluate the state of insulation deterioration of a load system with a system configuration that is simpler than conventional systems. Therefore, as described above, the evaluation system 1 is particularly suitable for electrical equipment EE where it is difficult or impossible to install a ZCT due to space restrictions for installing the equipment.

[0105] In addition, as described above, the information processing device 10 can individually evaluate the insulation deterioration state of each of the N load systems. For this reason, the evaluation system 1 is particularly suitable when N is large. The information processing device 10 can present the risk level for each of the N load systems to the manager of the load systems. This allows the manager to create maintenance plans for a large number of load systems more easily than before.

[0106] [Embodiment 2] (1) Unlike the example in Fig. 1, the information processing device 10 may be located outside the electrical equipment EE. The information processing device 10 may be communicably connected to the CT set 70 so as to be able to acquire the first to third detection values ​​from the CT set 70.

[0107] Furthermore, the information processing device 10 does not necessarily have to be a single device. For example, the information processing device 10 may be embodied by a first arithmetic unit located inside the electrical equipment EE and a second arithmetic unit located outside the electrical equipment EE. As an example, the first arithmetic unit may have a data processing unit 11, and the second arithmetic unit may have an evaluation unit 12. In this case, it is sufficient that the first arithmetic unit and the second arithmetic unit are connected to each other so that they can communicate with each other.

[0108] (2) There may be cases where the first to third detection values ​​contain a relatively large amount of noise components. Therefore, an arbitrary filter set that removes the noise components from the first to third detection values ​​may be provided between the CT set 70 and the information processing device 10. In this case, the information processing device 10 acquires the first to third detection values ​​after the noise components have been removed by the filter set.

[0109] As an example, the filter set includes a first filter that removes noise components from the first detection value, a second filter that removes noise components from the second detection value, and a third filter that removes noise components from the third detection value. The first filter is located between the first CT 71 and the information processing device 10. The second filter is located between the second CT 72 and the information processing device 10. The third filter is located between the third CT 73 and the information processing device 10.

[0110] (3) There may be cases where the amplitudes of the first to third detection values ​​are relatively small. Therefore, an optional amplifier set that amplifies the amplitudes of the first to third detection values ​​may be provided between the CT set 70 and the information processing device 10. In this case, the information processing device 10 acquires the first to third detection values ​​after being amplified by the amplifier set.

[0111] As an example, the amplifier set includes a first amplifier that amplifies the amplitude of the first detection value, a second amplifier that amplifies the amplitude of the second detection value, and a third amplifier that amplifies the amplitude of the third detection value. The first amplifier is located between the first CT 71 and the information processing device 10. The second amplifier is located between the second CT 72 and the information processing device 10. The third amplifier is located between the third CT 73 and the information processing device 10.

[0112] As is clear from the above descriptions, both the filter set and the amplifier set may be provided between the CT set 70 and the information processing device 10. In this case, the information processing device 10 acquires the first to third detection values ​​that have been amplified by the amplifier set and from which noise components have been removed by the filter set.

[0113] (4) To improve the accuracy of Io' calculated by the information processing device 10, it is desirable that the characteristics of the first CT 71, the second CT 72, and the third CT 73 are as consistent as possible. However, in reality, there may be variations in the characteristics of the first CT 71, the second CT 72, and the third CT 73. In this case, the variations may also cause a decrease in the accuracy of Io'.

[0114] Therefore, the information processing device 10 may correct the first to third detection values ​​in consideration of variations in the characteristics between the first CT 71, the second CT 72, and the third CT 73. In this case, the information processing device 10 calculates Io' based on the corrected first to third detection values. This makes it possible to prevent a decrease in the accuracy of Io' even when variations in the characteristics exist between the first CT 71, the second CT 72, and the third CT 73.

[0115] [Software implementation example] The functions of the evaluation system 1 (hereinafter referred to as the "device" for convenience) can be realized by a program for causing a computer to function as the device, and by a program for causing a computer to function as each control block of the device (particularly each part included in the information processing device 10).

[0116] In this case, the device includes a computer having at least one control device (e.g., a processor) and at least one storage device (e.g., a memory) as hardware for executing the program. The control device and storage device execute the program, thereby realizing the functions described in each of the above embodiments.

[0117] The program may be non-transitory and may be recorded on one or more computer-readable recording media. The recording media may or may not be included in the device. In the latter case, the program may be supplied to the device via any wired or wireless transmission medium.

[0118] In addition, some or all of the functions of the control blocks can be realized by logic circuits. For example, an integrated circuit in which a logic circuit that functions as each of the control blocks is formed is also included in the scope of one aspect of the present invention. In addition, the functions of the control blocks can be realized by, for example, a quantum computer.

[0119] Furthermore, each process described in each of the above embodiments may be executed by AI (Artificial Intelligence). In this case, the AI ​​may run on the control device or on another device (for example, an edge computer or a cloud server).

[0120] 〔summary〕 An information processing device according to a first aspect of the present invention is an information processing device for evaluating an insulation deterioration state of a load system including a load and a three-phase distribution line that supplies three-phase AC power to the load, the three-phase distribution line having a first phase distribution line, a second phase distribution line, and a third phase distribution line, and the information processing device includes a first Current Transducer (CT) that detects a first phase AC current flowing through the first phase distribution line. a first detection value that is a detection value of the first-phase AC current from a transformer (transformer); a second detection value that is a detection value of the second-phase AC current from a second CT that detects the second-phase AC current flowing in the second-phase distribution line; a third detection value that is a detection value of the third-phase AC current from a third CT that detects the third-phase AC current flowing in the third-phase distribution line; an estimate of a zero-phase current flowing in the three-phase distribution line based on the first detection value, the second detection value, and the third detection value; an average value of a plurality of the estimates for a first predetermined period; a minimum value of a plurality of the average values ​​for a second predetermined period that includes a plurality of the first predetermined periods; a value obtained by subtracting the minimum value from the average value for the first predetermined period as an evaluation object value corresponding to the plurality of estimates for the first predetermined period; and an evaluation object value corresponding to the plurality of estimates for the first predetermined period is evaluated based on a cumulative value of the time during which the evaluation object value exceeded a current threshold.

[0121] In the information processing device of aspect 2 of the present invention, in aspect 1, the length of the first specified period may be greater than or equal to 1 day and less than or equal to 5 days, and the length of the second specified period may be greater than or equal to 30 days and less than or equal to 90 days.

[0122] The information processing device according to a third aspect of the present invention, in the first or second aspect, may set a danger level as a discrete value indicating the evaluation result of the insulation degradation state based on the evaluation object value and the cumulative value.

[0123] In an information processing device according to aspect 4 of the present invention, in aspect 3, multiple current thresholds may be set, and the information processing device may set the danger level based on which of the multiple current thresholds the evaluation target value exceeded and for how long.

[0124] An evaluation system according to a fifth aspect of the present invention may include the information processing device according to any one of the first to fourth aspects, the first CT, the second CT, and the third CT.

[0125] An information processing method according to a sixth aspect of the present invention is an information processing method for evaluating an insulation deterioration state of a load system including a load and a three-phase distribution line that supplies three-phase AC power to the load, the three-phase distribution line having a first phase distribution line, a second phase distribution line, and a third phase distribution line, the information processing method including: acquiring a first detected value that is a detected value of the first-phase AC current from a second CT that detects the second-phase AC current flowing in the second-phase distribution line; acquiring a second detected value that is a detected value of the second-phase AC current from a third CT that detects the third-phase AC current flowing in the third-phase distribution line; calculating an estimated value of the zero-phase current flowing in the three-phase distribution line based on the first detected value, the second detected value, and the third detected value; calculating an average value of the plurality of estimated values ​​in a first predetermined period; extracting a minimum value from the plurality of average values ​​in a second predetermined period that includes the plurality of first predetermined periods; calculating a value obtained by subtracting the minimum value from the average value in the first predetermined period as an evaluation object value corresponding to the plurality of estimated values ​​in the first predetermined period; and evaluating the insulation degradation state based on a cumulative value of the time during which the evaluation object value exceeds a current threshold.

[0126] [Additional Notes] One aspect of the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of one aspect of the present invention. [Explanation of symbols]

[0127] 1. Rating System 10. Information processing equipment 11 Data processing section 12 Evaluation Section 70 CT set 71 1st CT 72 2nd CT 73 3rd CT HL 3-phase distribution wire SL1 Phase 1 distribution wire SL2 Phase 2 power cable SL3 Phase 3 distribution wire LD load UN load system TH1 1st current threshold TH2 2nd current threshold TH3 3rd current threshold

Claims

1. 1. An information processing device for evaluating an insulation deterioration state of a load system including a load and a three-phase distribution line that supplies three-phase AC power to the load, the three-phase distribution line includes a first-phase distribution line, a second-phase distribution line, and a third-phase distribution line; The information processing device includes: acquiring a first detection value, which is a detection value of the first-phase AC current, from a first current transformer (CT) that detects a first-phase AC current flowing through the first-phase distribution line; acquiring a second detection value, which is a detection value of the second-phase AC current, from a second CT that detects the second-phase AC current flowing in the second-phase distribution line; acquiring a third detection value, which is a detection value of the third-phase AC current, from a third CT that detects the third-phase AC current flowing in the third-phase distribution line; calculating an estimated value of a zero-phase current flowing in the three-phase distribution line based on the first detected value, the second detected value, and the third detected value; calculating an average value of the plurality of estimated values ​​over a first predetermined period; extracting a minimum value from among the plurality of average values ​​in a second predetermined period that includes the plurality of first predetermined periods; calculating a value obtained by subtracting the minimum value from the average value for the first predetermined period as an evaluation target value corresponding to the plurality of estimated values ​​for the first predetermined period; An information processing device that evaluates the insulation deterioration state based on a cumulative value of the time during which the evaluation object value exceeds a current threshold.

2. the length of the first predetermined period is not less than one day and not more than five days; The information processing device according to claim 1 , wherein the length of the second predetermined period is not less than 30 days and not more than 90 days.

3. The information processing apparatus according to claim 1 , further comprising: setting a danger level as a discrete value indicating an evaluation result of the insulation deterioration state based on the evaluation object value and the cumulative value.

4. A plurality of the current thresholds are set, The information processing apparatus according to claim 3 , wherein the danger level is set based on which of a plurality of current thresholds the evaluation target value has exceeded and for how long.

5. The information processing device according to claim 1 ; An evaluation system comprising the first CT, the second CT, and the third CT.

6. 1. An information processing method for evaluating an insulation deterioration state of a load system including a load and a three-phase distribution line that supplies three-phase AC power to the load, comprising: the three-phase distribution line includes a first-phase distribution line, a second-phase distribution line, and a third-phase distribution line; The information processing method includes: acquiring a first detection value, which is a detection value of the first-phase AC current, from a first current transformer (CT) that detects a first-phase AC current flowing in the first-phase distribution line; acquiring a second detection value, which is a detection value of the second-phase AC current, from a second CT that detects the second-phase AC current flowing in the second-phase distribution line; acquiring a third detected value, which is a detected value of the third-phase AC current, from a third CT that detects the third-phase AC current flowing in the third-phase distribution line; calculating an estimated value of a zero-phase current flowing in the three-phase distribution line based on the first detected value, the second detected value, and the third detected value; calculating an average value of a plurality of the estimated values ​​over a first predetermined period; extracting a minimum value from among a plurality of the average values ​​in a second predetermined period that includes a plurality of the first predetermined periods; calculating a value obtained by subtracting the minimum value from the average value during the first predetermined period as an evaluation target value corresponding to the plurality of estimated values ​​during the first predetermined period; and evaluating the insulation deterioration state based on a cumulative value of the time during which the evaluation object value exceeds a current threshold.

Images