KR101213163B1 - Method and system for a analyzing failure of power line using protective relay - Google Patents

Abstract

The present invention provides a delay time calculating unit for calculating a time interval between a pickup time of a fault occurrence and an operation start time of a protection relay due to the fault through a secondary current transformer when a fault occurs in a distribution line; A diagnostic fault current calculating unit calculating a pickup multiple based on the lever value and the delay time of the protection relay, and calculating a diagnostic fault current using the pickup multiple, the tap value of the protective relay, and the current ratio; And a failure point determination unit which determines a failure point by comparing current values of a plurality of estimated failure currents with current values of the diagnostic failure current.

Description

Distribution line failure diagnosis method and system using protective relay {METHOD AND SYSTEM FOR A ANALYZING FAILURE OF POWER LINE USING PROTECTIVE RELAY}

The present invention relates to a method and a system for diagnosing a failure of a distribution line. More specifically, the diagnostic failure current is calculated by using time information on a failure current flowing through the distribution line using a protection relay, and the system is stored in a distribution line stored in a database. The present invention relates to a failure diagnosis method and system for a distribution line that calculates a plurality of estimated failure currents by using related data, and calculates a failure point of a distribution line having a failure by repeatedly comparing the diagnosis failure current and the estimated failure current.

In general, the protection relay is installed to discriminate the failure state of the transmission line and the distribution line, which are complexly distributed by region, to block the fault line section at high speed. The protection relay of the power system receives the voltage and current from the transmission system and the distribution line, such as a transmission line, a transformer, a bus, respectively, and generates digital voltage / current data through high-speed sampling processing and analog / digital conversion.

When the data of the digital voltage / current is diagnosed by the protection algorithm and the failure state is determined by the accident, the break point can be blocked at high speed. This can minimize the risk of many different safety accidents occurring in the general public.

This conventional fault diagnosis can be performed in a 154kV protection system by separately installing a fault recorder or by using a protection relay having a fault point position diagnosis function such as a street expression.

However, the protection relay of the 22.9kV distribution line is operated without a separate failure analysis function such as the suggestion of a failure point. In case of fault diagnosis of 22.9kV system, the electromagnetic protection relay or digital protection relay installed in the existing site cannot record the fault current when a fault occurs, and the existing SCADA monitoring system acquires the load current at all times, not for fault current measurement. Because it is the purpose of use, it is impossible to acquire fault current, so it is impossible to obtain information to infer the fault point.

Therefore, the conventional 22.9kV system protection relay has a failure point expression function compared to the 154kV system, and it is pointed out that the distribution line system is difficult to determine the failure point when a failure occurs in the distribution line due to the installation of a failure recording device.

In order to solve this problem, it is pointed out that a problem of high installation cost is required because a separate analysis system has to be replaced with the latest digital protection relay capable of acquiring and transmitting a fault current. .

The present invention is to solve the above problems, by using the existing protective relay or the skadar to detect the time information on the fault current flowing in the distribution line and calculate a diagnostic fault current based on this, the diagnostic fault current and fault It is an object of the present invention to provide a method and system for diagnosing a failure of a distribution line using a protection relay that can obtain information on a point of failure at high speed by repeatedly comparing estimated fault currents containing information about a point and can quickly diagnose the point of failure. do.

In order to achieve the above object, a distribution line failure diagnosis system using a protection relay according to an embodiment of the present invention, when the failure occurs in the distribution line, the pick-up time of the occurrence of the failure and the operation start time of the protection relay due to the failure A delay time calculating unit calculating a time interval of a delay time; A diagnostic fault current calculating unit calculating a pickup multiple based on the lever value and the delay time of the protection relay, and calculating a diagnostic fault current using the pickup multiple, the tap value of the protective relay, and the current ratio; And a failure point determination unit which determines a failure point by comparing current values of a plurality of estimated failure currents with current values of the diagnostic failure current.

In a distribution line fault diagnosis system using a protection relay according to an embodiment of the present invention, the diagnostic fault current calculating unit calculates the pickup multiple by inverting the time characteristic function of the protection relay.

In a distribution line fault diagnosis system using a protection relay according to an embodiment of the present invention, the diagnosis fault current calculating unit calculates the fault fault current based on a fault fault current = tap value × current ratio × pickup drainage.

Distribution line failure diagnosis system using a protection relay according to an embodiment of the present invention, characterized in that it further comprises a display unit for displaying information about the failure point.

Distribution line failure diagnosis system using a protection relay according to an embodiment of the present invention, the transmission and reception unit for transmitting the information on the failure point by wire or wireless to the remote monitoring unit; characterized in that it further comprises.

In a distribution line failure diagnosis system using a skid according to another embodiment of the present invention, the delay time calculation unit increases the current at which the measured current value flowing through the distribution line through the SCADA connected to the distribution line is greater than the rated current. Detecting a time, a current decrease time which is a time when the rated current becomes smaller than a predetermined ratio, and an operation time, and calculate a delay time using the current increase time, the current decrease time, and the operation time. It is done.

In a distribution line failure diagnosis method using a protection relay according to another embodiment of the present invention, in a distribution line failure diagnosis method using a distribution line failure diagnosis system including a delay time calculation unit, a diagnosis failure current calculation unit, and a failure point determination unit, The delay time calculating unit obtains the pick-up time of the fault occurrence through the auxiliary current transformer when a fault occurs in the distribution line, obtains the start time of operation of the protection relay due to the fault, and calculates the time interval between the pick-up time and the start time of the operation. Delay time calculation step of calculating the delay time (S100); The diagnostic fault current calculation unit calculates a pickup multiplier based on the lever value and the delay time of the protective relay, and calculates a diagnostic fault current using the pick-up multiplier, the tap value of the protective relay, and the current ratio. Step S200; And a failure point determining step of determining a failure point by comparing the current value of the estimated failure current with the current value of the estimated failure current by the failure point determination unit (S300). It includes.

The distribution line fault diagnosis method using a protection relay according to another embodiment of the present invention is characterized in that the diagnostic fault current calculating unit calculates the pickup multiple by inverting the time characteristic function of the protection relay.

In a distribution line failure diagnosis method using a protection relay according to another embodiment of the present invention, in the diagnosis fault current calculation step (S200), the diagnosis fault current calculation unit may be configured by a diagnosis fault current = tap value × current ratio × pickup drainage. The diagnostic fault current is calculated.

In a distribution line failure diagnosis method using a protection relay according to another embodiment of the present invention, the distribution line failure diagnosis system further includes a display unit, and after the failure point determination step (S300), the display unit, the failure point And displaying information on the.

In a distribution line failure diagnosis method using a protection relay according to another embodiment of the present invention, the distribution line failure diagnosis system further includes a transceiver, and after the step (S300) of determining the failure point, the transmission and reception unit, And transmitting the information on the failure point to the remote monitoring operation unit by wire or wirelessly.

In the distribution line failure diagnosis method using a skada according to another embodiment of the present invention, the step of calculating the delay time (S100), the delay time calculation unit when the failure occurs in the distribution line measured current value through the SCADA (SCADA) Detects a current increase time at which time is greater than the rated current, a current decrease time at which time is smaller than a predetermined ratio of the rated current, and an operation time, and detects the current increase time, the current decrease time and the operation time. The delay time is calculated by using.

According to the present invention, time information on a fault current flowing in a distribution line is detected by using a protective relay or a skid, and a diagnostic fault current is calculated based on the estimated fault current and a fault current corresponding to a fault point. By comparing the fault current, it acquires the information on the fault point at high speed and provides the effect of quick fault diagnosis.

1 is a block diagram of a failure diagnosis system using a protection relay according to the present invention,
2 is a schematic diagram of obtaining operation information of a protective relay for a distribution line according to the present invention;
3 is a flowchart of a failure diagnosis method using a protection relay according to the present invention;
4 is a block diagram of a failure diagnosis system using a skada according to another embodiment of the present invention,
5 is a flowchart illustrating a fault diagnosis method using a skada according to another embodiment of the present invention.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a failure diagnosis system using a protection relay according to the present invention.

The failure diagnosis system may include a delay time calculator 100, a diagnosis fault current calculator 200, a failure point determiner 300, and a database 400.

The delay time calculating unit 100 may detect a change in current appearing when a fault is broken and when the auxiliary current transformer is input. By detecting the change in the current in this way it is possible to obtain the operating time time (C _c ) and the operating time (α) of the protective relay.

Delay time calculation unit 100 may calculate a motion time (C _r) by correcting an operation time (α) to the operation time point (C _c). In addition, the delay time calculating unit 100 may calculate the delay time C _d by using the operation time C _r and the pick-up time C _p of the fault current. The time C _d can be calculated.

The diagnostic fault current calculator 200 receives a delay time C _d from the delay time calculator 100 and receives a lever value of the protection relay from the database 400. The diagnostic fault current calculator 200 calculates a diagnosis fault current I _f using the delay time C _d and the lever value. Since this has been described above, even if the detailed description is omitted, those skilled in the art can easily understand.

The failure point determination unit 300 may repeatedly calculate the estimated failure current I _e while varying the impedance by using information of the ring auxiliary current transformer, bus impedance, and line impedance according to a power failure state.

The failure point determination unit 300 determines the failure point E _i by comparing the diagnostic failure current received from the diagnostic failure current calculation unit 200 with the estimated failure current repeatedly calculated.

In addition, the failure point determination unit 300 may display information about the point of failure (E _i) to the display portion and the display portion is electrically connected to that is capable of displaying information about the failure point (E _i). The display unit may be preferably configured with various display means such as a CRT monitor, a liquid crystal display (LCD), a plasma display panel (PDP), and a light emitting diode (LED) display.

In addition, the failure point determination unit 300 may further include a wired / wireless interface that can interface with an external device in a wired or wireless manner. The wired / wireless interface unit may be implemented by various interface means such as an RS-232C interface, a USB interface, or a TCP / IP interface.

The database unit 400 may receive and store a lever value, a tap value, a bus impedance of a power distribution line, and a line impedance value of the protection relay, and may be electrically connected to the diagnostic fault current calculator 200 and the fault point determiner 300. Can be.

2 shows a schematic diagram of obtaining operation information of a protection relay for a distribution line according to the present invention.

Referring to Figure 2, looking at the approximate acquisition method of the operation information of the protective relay for the distribution line as follows. The power distribution line supply system 10 is supplied with power to the system bus 11 through the peripheral voltage transformer 14 through the secondary pressure circuit breaker 12. After that, it is configured to supply to the power distribution line 13 through each breaker (12).

The protection of each distribution line 13 has a protection relay for each distribution line for each circuit breaker 12 and detects a fault current in the event of a fault and operates each corresponding circuit breaker 12 by using a time element and an instantaneous element. It performs a function to block the short circuit and ground fault occurring in the furnace (13) section.

The operation time of the protection relay installed in the distribution line 13 can be known the pick-up time (C _p ) of the fault current using the ring auxiliary current transformer (17). The operation starting time C _r of the protection relay 13 of the subsequent stage can be obtained by correcting the operation time α of the breaker from the operating time C _c of the breaker.

3 is a flowchart of a distribution line failure diagnosis method using a protection relay according to the present invention. In more detail, referring to FIG. 3, a failure diagnosis method of a distribution line using a protection relay is as follows.

The distribution line failure diagnosis method using the protection relay may include a delay time calculating step (S100) of calculating a time interval as a delay time, a step of calculating a diagnostic failure current (S200), and a step of determining a failure point (S300). have.

Delay time calculation step (S100), the delay time calculation unit 100 obtains the pick-up time of the fault current through the ring auxiliary current transformer when a failure occurs in the distribution line, the time of the operation start time of the pick-up time and the protection relay by the fault The interval is calculated as the delay time.

In more detail, the delay time calculation unit 100 receives the operation time and the operation time of the protection relay. The delay time calculation unit 100 obtains the pick-up time of the fault current through the ring auxiliary current transformer 170, calculates the operation time of the protection relay, and calculates the delay time using the delay time. That is, the delay time calculator 100 may calculate the operation time of the protection relay by subtracting the operation time required from the operation time of the protection relay.

In the diagnosis fault current calculating step S200, the diagnosis fault current calculating unit 200 receives a delay time from the delay time calculating unit 100, and receives a lever value of the protection relay from the database unit 400.

The time limit function function (Fry ()) of the protection relay in case of a distribution line failure is a function expression of the lever curve of the protection relay with strong time characteristic.

For example, the time characteristic of the digital protective relay can be expressed as follows.

Fry (T _p , lever value) = (39.85 / (pickup multiple (T _p )) ^ ^1.95 -1) +1.084) × lever value × 60/10 [cycle]

Here, when the lever value of the protective relay is 3 and the pickup multiplier is set to 10 [multiplier], the time limit operation time = (39.85 / (10 ^{^ 1.95} -1) +1.084) * 3 * 60/10 = 28 [cycle] Can be. This time characteristic function is for illustrative purposes only and is not intended to limit the technical scope of the present invention.

The pickup drainage can be obtained by inversely converting the time characteristic (Fry ()) of the protection relay installed in the distribution line.

Pickup multiplier = (39.85 / (| lever value * 6 / time limit-1.084 | +1) [multiplier]

That is, when a failure occurs in the distribution line, the diagnostic failure current calculation unit 200 obtains, from the delay time calculation unit 100, a delay time that is information of the time limit operation time. The diagnostic fault current calculating unit 200 may calculate the pickup multiplier by the following inverse time characteristic function Gry () using the delay time and the lever value.

Gry (Lever value, delay time) = (6 × 39.85 × Lever value / delay time (C _d )) ^∧1.95 [multiple]

Looking at the inverse time characteristic function, it can be seen that the pickup multiple is inversely related to the time limit operation time (eg, delay time). The time-out time increases as the failure point moves away from the bus. Therefore, as the time limit operation time increases, the value of the pickup multiple decreases rather.

The diagnostic fault current calculator 200 receives a tap value and a current ratio (eg, 600/5) of the protection relay from the database 400. When a failure occurs at a predetermined point of the distribution line, the delay time calculation unit 100 calculates the delay time in accordance with the above-described method, and the diagnostic failure current calculation unit 200 calculates the pickup multiple using the delay time.

In addition, the diagnostic fault current calculating unit 200 calculates a diagnostic fault current using the pickup multiple, the tap value, and the current ratio according to Equation 1 below.

For example, the tap values is 4 [A], and a current ratio of 600/5, a multiple pick-up (T _p) is 10 [drain], diagnosis fault currents (I _f) by the equation (1) If the I _f = 4 * 600/5 * 10 = 4,800 [A].

According to the distribution line failure diagnosis method using the protection relay of the present invention, when a failure occurs in the distribution line, it can be converted to a pickup multiplier using time information on the fault current, and the diagnostic failure current can be calculated based on the pickup multiplier. Therefore, it is possible to diagnose a failure of the distribution line by utilizing a conventional protective relay.

In the determining of the failure point (S300), the failure point determination unit 300 calculates the estimated failure current and compares it with the diagnostic failure current to determine the failure point. Looking at how the failure point determination unit 300 calculates the estimated failure current, the failure point determination unit 300 determines the phase in which the failure occurs through the ring auxiliary current transformer, and the failure of the distribution line from the database 400 Receive the values of bus impedance and line impedance as information on. The failure point determination unit 400 calculates an estimated impedance using the bus impedance and the line impedance. For example, the estimated fault current is calculated according to any one of the fault conditions shown in Equation 2 below.

However, in the case of three-phase power supply, if one-wire disconnection or two-wire disconnection occurs, the fault current cannot be calculated according to the symmetry condition due to asymmetry.

Therefore, in the case of an asymmetric three-phase power supply, a plurality of estimated fault currents can be calculated by the so-called symmetrical coordinate method. In addition to calculating the estimated fault current, the pickup multiple can be calculated.

The failure point determination unit 300 repeatedly calculates the estimated failure current to determine the failure point by comparing with the diagnostic failure current received from the diagnostic failure current calculation unit 200. More specifically, it is as follows.

For example, when the diagnostic fault current calculating unit 200 calculates 4800 [A] as the diagnostic fault current, the fault point determining unit 300 repeatedly calculates the estimated fault current while varying the bus impedance and the line impedance, and as a result, Is compared with the diagnostic fault current.

That is, when the pickup multiplier and the estimated fault current are calculated while increasing by 50cm from the 0km point, it is shown in Table 1 below.

Distance [Km] Pickup multiple [multiple] Estimated Fault Current [A] 2.15 10.09 4,846 2.20 10.02 4,809 2.25 9.94 4,773 2.30 9.87 4,737

The failure point determination unit 300 repeatedly calculates the estimated fault current while varying the false distance (bus impedance or line impedance), and calculates the diagnosis fault current and the difference value as shown in Equation 3 below.

By repeatedly calculating the difference value between the diagnostic fault current and the estimated fault current while varying the bus impedance or the line impedance in the same manner as in Equation 3 above, when the difference value is within a predetermined reference value, Information can be used to determine the point of failure.

Referring to the case shown in Equation (3), the estimated failure at that time since the difference value between the estimated fault current and the diagnostic fault current in df (2.20 km) falls within a predetermined reference value (for example, already set to 40 [A]). The fault point can be determined using the 2.20km of the distance, which is information about the current.

4 is a block diagram of a failure diagnosis system using a scarda according to another embodiment of the present invention.

Referring to FIG. 4, a failure diagnosis system using a scarda may include a delay time calculator 100, a diagnosis fault current calculator 200, a failure point determiner 300, and a database 400.

The delay time calculating unit 110 receives information on the current of the power distribution line through the skid, and delay time (C) using the current increase time (C _f ), the current decrease time (C _z ), and the operation time (α). C _d ) can be calculated.

In other words, if a fault current occurs in the distribution line, the current flowing through the distribution line is measured, but the current increase time (C _f ) at which the measured current value is equal to or greater than the rated current is set as the fault point. The point of time at which the rated current falls below a preset ratio is referred to as the current reduction time (C _z ) at which the fault is to be solved, and the breaker operation time is taken as the operating time (a).

The current increase time (C _f ) may be viewed as the point at which the magnitude of the current flowing in the distribution line is greater than or equal to the rated current, but preferably, the magnitude of the current flowing in the distribution line is not less than 150% of the magnitude of the rated current. It can also be seen as the current increase time.

In general, however, if the magnitude of the current flowing in the distribution line is greater than the magnitude of the rated current, it may not only be caused by the distribution line failure but also by the load variation.

Therefore, when the current increase time C _f is determined to be greater than the rated current, it may be determined as the current increase time C _f even when it is not a failure. However, when the current flowing through the power distribution line exceeds the magnitude of the rated current due to the load variation, the change of current occurs over a period of tens to hundreds of cycles, so the change rate is not abrupt. On the other hand, since the breakdown of the distribution line occurs and the change of the current flowing through the distribution line occurs over several cycles, for example, two to three cycles, the change rate is abrupt. Based on the above-mentioned information also by the algorithm which judges the time which exceeds the magnitude | size of a rated current as the current increase time (C _f ), it can be judged whether it is a failure of a distribution line. Will be.

The current reduction time C _z may be viewed as a point in time at which the magnitude of the current flowing in the distribution line is less than or equal to a preset ratio of the rated current. In this case, the preset ratio may be set to 0.1 to 1%. Theoretically, if the breaker operates, the current flowing in the distribution line may decrease to 0A, but the current of 2 to 5% of the rated current may flow in the distribution line depending on the condition of the breaker or distribution line. . Thus, for example, the preset ratio may be set to 1%. The preset ratio may be variously modified and set by those skilled in the art without departing from the spirit of the present invention in consideration of the state of the circuit breaker or the distribution line.

Alternatively, the current reduction time C _z may preferably be determined by the time when the current value flowing in the distribution line reaches 0 [A], and in some cases, the time when the load current disappears is used as the current reduction time. You can judge.

Therefore, the delay time calculating unit 110 calculates the one time electrical delay time C _d by using the following equation (4) to calculate the failure time (C _f ), the failure elimination time (C _z ), and the operation time (a). .

The diagnostic fault current calculator 200 calculates a pickup multiplier T _p using the delay time C _d received from the delay time calculator 110 and the lever value received from the database 400. The diagnostic fault current calculator 200 may receive a tap value from the database 400, receive a current ratio, and calculate the diagnostic fault current I _f using the method described above.

The failure diagnosis system using the SCADA has an advantage of calculating the delay time C _d using current information of the SCADA without separately installing the ring auxiliary current transformer 17.

5 is a flowchart illustrating a failure diagnosis method using a SCADA according to another embodiment of the present invention.

Referring to FIG. 5, a failure diagnosis method using a scarda has a distinctive feature in an algorithm for obtaining a delay time C _d when compared with a failure diagnosis method of a distribution line using the protection relay shown in FIG. 3.

That is, as described above, the failure diagnosis system using the scarda may calculate the delay time C _d using the current information of the scarda without separately installing the ring auxiliary current transformer 17.

In addition, preferred embodiments of the present invention are disclosed for the purpose of illustration, those skilled in the art will be able to make various modifications, changes, additions, etc. within the spirit and scope of the present invention, such modifications, changes, etc. fall within the scope of the claims Should be seen.

Claims (12)

A delay time calculating unit for calculating, as a delay time, a time interval between a pickup time of the occurrence of a failure and an operation start time of the protection relay due to the failure through an auxiliary current transformer when a failure occurs in a distribution line;
A diagnostic fault current calculating unit calculating a pickup multiple based on the lever value and the delay time of the protection relay, and calculating a diagnostic fault current using the pickup multiple, the tap value of the protective relay, and the current ratio; And
A failure point determination unit which determines a failure point by comparing current values of a plurality of estimated failure currents with current values of the diagnostic failure current;
Distribution line failure diagnosis system using a protective relay comprising a.
The method of claim 1,
The diagnostic fault current calculating unit calculates the pickup multiple by inversely converting the time-limiting characteristic function of the protection relay.
The method of claim 1, wherein the diagnostic fault current calculation unit,
Diagnostic fault current = tap value × current ratio × pickup
Distribution line fault diagnosis system using a protective relay, characterized in that for calculating the diagnostic fault current by.
The method of claim 1,
Distribution line failure diagnosis system using a protection relay further comprises a; display unit for displaying information about the failure point.
The method of claim 1,
Distribution line failure diagnosis system using a protective relay further comprising; transmitting and receiving unit for transmitting the information on the failure point by wire or wireless to the remote monitoring operation unit.
The method of claim 1,
The delay time calculating unit may include a current increase time at which the measured current value flowing through the SCADA connected to the power distribution line is greater than the rated current, a current decrease time at which the time is smaller than a predetermined ratio of the rated current, And detecting the operation time, and calculating the delay time using the detected current increase time, current decrease time, and operation time. In the distribution line failure diagnosis method using a distribution line failure diagnosis system including a delay time calculation unit, a diagnostic failure current calculation unit and a failure point determination unit,
The delay time calculating unit obtains the pick-up time of the fault occurrence through the auxiliary current transformer when a fault occurs in the distribution line, obtains the start time of operation of the protection relay due to the fault, and calculates the time interval between the pick-up time and the start time of the operation. Delay time calculation step of calculating the delay time (S100);
The diagnostic fault current calculation unit calculates a pickup multiplier based on the lever value and the delay time of the protective relay, and calculates a diagnostic fault current using the pick-up multiplier, the tap value of the protective relay, and the current ratio. Step S200; And
A failure point determination step of determining a failure point by comparing the current value of the estimated failure current with the current value of the estimated failure current by the failure point determination unit (S300);
Distribution line failure diagnosis method using a protective relay comprising a.
According to claim 7, In the diagnostic fault current calculation step (S200),
The diagnostic fault current calculating unit calculates the pickup multiple by inverting the time characteristic function of the protection relay. According to claim 7, In the diagnostic fault current calculation step (S200),
The diagnostic fault current calculation unit,
Diagnostic fault current = tap value × current ratio × pickup
The fault diagnosis method for a distribution line using a protective relay, characterized in that for calculating the diagnostic fault current.
The method of claim 7, wherein
The distribution line failure diagnosis system further includes a display unit,
After the failure point determination step (S300), the display unit, the distribution line failure diagnosis method using a protective relay, characterized in that further comprising the step of displaying information about the failure point.
The method of claim 7, wherein
The distribution line failure diagnosis system further includes a transceiver,
After the step of determining the failure point (S300), the transmission line failure using the protective relay, characterized in that further comprising the step of transmitting the information on the failure point to the remote monitoring operation by wire or wireless. Diagnostic method.
The method of claim 7, wherein calculating the delay time (S100),
When the delay time calculation unit fails in the distribution line, the current increase time, which is the point of time when the measured current value becomes larger than the rated current through the SCADA, the current decrease time, which is the time point, which becomes smaller than the preset ratio of the rated current, and operation required A method for diagnosing a distribution line failure using a protective relay, comprising detecting a time and calculating a delay time using the detected current increase time, current decrease time, and operation time.

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