METHOD AND DEVICE FOR IMPROVING CURRENT TRANSMISSION RELIABILITY

Information

  • Patent Application
  • 20230055173
  • Publication Number
    20230055173
  • Date Filed
    September 16, 2021
    2 years ago
  • Date Published
    February 23, 2023
    a year ago
Abstract
A method and a device for improving current transmission reliability are provided. The method includes: selecting effective points; performing technical measurement; generating a threshold: generating a critical abnormal alarm time threshold t1, generating a critical defect alarm time threshold t2, and generating a non-critical abnormal electric leakage threshold t3; and generating a necessary remaining life number Δt21, wherein Δt21=t2−t1. By judging whether a current carrying capacity passing through an electric transmission line portion at a certain time exceeds an allowable current carrying capacity, the alarm time threshold t1 is far lower than 20%, an alarm is capable of being given for an abnormal situation in time, and a necessary remaining life of an electric device or system can be predicted by randomly measuring an input current Iin i, an output current Iout i, and errors of input and output currents, so that cross liability is avoided.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims foreign priority of Chinese Patent Application No. 202110928383.9 with a filing date of Aug. 13, 2021 in the China National Intellectual Property Administration, the disclosures of all of which are hereby incorporated by reference.


TECHNICAL FIELD

The present invention relates to a method and a device for improving current transmission reliability, and more particularly, to a method and a device for improving civil current transmission reliability for preventing houses from being destroyed.


BACKGROUND

Current transmission refers to an electric current (at a current density before conversion) passing through a field. With the rapid development of the national economy and the improvement of people's living standards with each passing year, the consumption of various electric devices has been increased sharply. Electric fire accidents have also been soared, ranking first among all kinds of fires. If electric leakage occurs during current transmission, it is easy to cause damage to the electric devices and even fire, which leads to major accidents such as house destruction, casualties and so on, thus causing huge losses to the national economy and people's lives and property.


In the prior art, Chinese patent No. CN201710533497.7 discloses an “online insulating monitoring-type resistive device for monitoring and detecting electric leakage electrical fire”, which monitors and detects the electric leakage electrical fire through a current detection unit, a current digital filtering unit, a voltage detection unit, a voltage digital filtering unit, a signal separation unit, a display unit, an alarm unit and a monitoring module, and a system structure is too complicated.


Chinese patent No. CN201910419440.3 discloses “a method for preventing false alarm of electric leakage”, it is unscientific to set an alarm threshold to be 20% in the patent. For example, for places with high requirements on a safety level of protection and early warning, an excessively high alarm threshold cannot give an alarm for abnormal situations in time, which will delay a maintenance progress and cause unnecessary losses.


In the prior art, a remaining service life of an electric device or system cannot be predicted, and there is also a technical problem of cross liability caused by overlapping detection methods or data, thus having poor user experience.


SUMMARY

The present invention aims to provide a method and a device for improving current transmission reliability, so as to solve technical problems of an excessively high alarm threshold, an unpredicted remaining life of an electric device or system, an easily caused cross liability in the prior art. The technical solutions used in the present invention to solve the technical problems are as follows.


A method for improving current transmission reliability includes:


step S100: selecting effective points: respectively selecting an input current effective point Iin and an output current effective point Iout at two ends of a hidden portion of an electric transmission line;


step S200: performing technical measurement: performing technical measurement on the effective points Iin and Iout selected in the step S100;


step S300: generating a threshold: generating a threshold according to measurement results in the step S200, including:


step S301: generating a critical abnormal alarm time threshold t1,


step S302: generating a critical defect alarm time threshold t2,


step S303: generating a non-critical abnormal electric leakage threshold t3;


step S400: randomly measuring an input current Iin i and an output current Iout i at the hidden portion of the electric transmission line;


step S500: randomly measuring an error δin 1 of the input current Iin i and an error δout 2 of the output current Iout i at the hidden portion of the electric transmission line; and


step S600: judging values of Iin i−Iout i and δin 1out 2,


If Iin i−Iout i is greater than in δin 1out 2, [formula 1]


generating a necessary remaining life number Δt21, wherein Δt21=t2−t1. [formula 2]


The further technical solution of the present invention further includes that: in the step S301, a judgment standard of the critical abnormal alarm time threshold t1 is that: if a current carrying capacity passing through an electric transmission line portion at a certain time exceeds an allowable current carrying capacity, then the time is the critical abnormal alarm time threshold t1.


Further, in the step S302, a calculation formula of the critical defect alarm time threshold t2 is: t2=t1(1+b) [formula 3]


in the formula 3, t1 is the critical abnormal alarm time threshold.


Further, in the step S303, a representation formula of the non-critical abnormal electric leakage threshold t3 is that: t3=Iin i−Iout iin 1out 2 [formula 4]


in the formula 4, the representation means that: at the time of electric leakage, a difference between the input current Iin i and the output current Iout i at the hidden portion of the electric transmission line randomly measured is greater than a sum of the error δin i of the input current Iin i and the error δout 2 of the output current Iout i at the hidden portion of the electric transmission line randomly measured; and


the time is the non-critical abnormal electric leakage threshold t3.


Further, in the step S600, the generating the necessary remaining life number Δt21 further includes: counting the necessary remaining life number Δt21 obtained according to the formula 2 to generate (μ21, σ21), and obtaining that the necessary remaining life number Δt21 is (μ21−Kσ21) [formula 5]


in the formula 5, K represents a standard deviation coefficient of normal distribution of Δt21, and a value of K ranges from 1 to 6;


σ21 represents a variance of the necessary remaining life number Δt21; and


μ21 represents a true value of the necessary remaining life number Δt21.


The present invention further provides a device for improving current transmission reliability, which includes:


a central processing unit;


an input current detection module configured for detecting an input current Iin i at a hidden portion of an electric transmission line randomly measured;


an output current detection module configured for detecting an output current Iout i at the hidden portion of the electric transmission line randomly measured;


a first sensor configured for feeding back the input current detected by the input current detection module to the central processing unit;


a second sensor configured for feeding back the output current detected by the output current detection module to the central processing unit;


a first alarm device configured for, when the input current Iin i or the output current Iout i exceeds the allowable current carrying capacity, giving an alarm under control of the central processing unit; and


a second alarm device configured for, in a case of the critical abnormal alarm time threshold t1, if the critical defect alarm time threshold t2 satisfies a formula t2=t1(1+b), giving an alarm under control of the central processing unit, wherein a value of b is selected based on a line type of the electric transmission line and LSL to USL curves, a is a standard deviation in the LSL to USL curves, and the value of b ranges from 0.75σ to 2.75σ.


According to the first technical solution of the present invention, in the present invention, by judging whether the current carrying capacity passing through the electric transmission line portion at a certain time exceeds the allowable current carrying capacity, if the current carrying capacity exceeds the allowable current carrying capacity, the time is the critical abnormal alarm time threshold t1, compared with the prior art, the alarm time threshold t1 is far lower than 20%, which is more scientific, and an alarm is capable of being given for an abnormal situation in time, which is convenient for quick maintenance to reduce unnecessary losses.


According to the second technical solution of the present invention, since the necessary remaining life number Δt21 is determined by the critical defect alarm time threshold t2 and the critical abnormal alarm time threshold t1, which is related to the line type of the electric transmission line and the LSL to USL curves, the present invention can predict the necessary remaining life of the electric device or system by randomly measuring the input current Iin i, the output current Iout i and the errors of the input and output currents.


According to the third technical solution of the present invention, in the device of the present invention, the input current detection module, the output current detection module, the first sensor, the second sensor, the first alarm device and the second alarm device all work independently and do not affect each other, so that there is no technical problem of cross liability caused by overlapping detection methods or data.


According to the fourth technical solution of the present invention, the present invention has a simple structure and a convenient and effective detection method, better improves civil current transmission reliability, and improves user experience.





BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 is a flow chart of a method for improving current transmission reliability in an embodiment of the present invention;



FIG. 2 is a schematic diagram of a principle of preventing current transmission in a critical state in an embodiment of the present invention;



FIG. 3 is a schematic diagram of a defect alarm time threshold t2 in an embodiment of the present invention;



FIG. 4 is a schematic diagram of a principle of preventing current transmission in a non-critical state in an embodiment of the present invention; and



FIG. 5 is a structure block diagram of a device for improving current transmission reliability in an embodiment of the present invention.





DETAILED DESCRIPTION

In order to make the above objectives, features and advantages of the present invention clearer and more understandable, the specific embodiments of the present invention are described in detail hereinafter with reference to the accompanying drawings. In the following description, many specific details are explained so as to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so that the present invention is not limited by the specific embodiments disclosed below.


In the description of the present invention, it shall be understood that the orientation or position relationship indicated by the terms “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “up”, “down”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “anticlockwise”, “axial”, “radial”, “circumferential”, and the like is based on the orientation or position relationship shown in the accompanying drawings, it is only for the convenience of description of the present invention and simplification of the description, and it is not to indicate or imply that the indicated device or element must have a specific orientation, and be constructed and operated in a specific orientation. Therefore, the terms shall not be understood as limiting the present invention.


Moreover, the terms “first” and “second” are used for descriptive purposes only and cannot be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated thereby. Thus, the features defined by “first” and “second” may explicitly or implicitly include one or more features. In the description of the present invention, the meaning of “multiple” is at least two, such as two, three, and so on, unless otherwise specifically defined.


With reference to FIG. 1 to FIG. 5, the present invention provides a method for improving current transmission reliability, which includes:


step S100: selecting effective points: respectively selecting an input current effective point Iin and an output current effective point Iout at two ends of a hidden portion of an electric transmission line, for example, the input current effective point Iin may be selected at an input end of a live wire of a hidden project and the output current effective point Iout may be selected at an output end of the live wire;


step S200: performing technical measurement: performing technical measurement on the effective points Iin and Iout selected in the step S100, wherein in the present invention, the technical measurement may refer to respectively measuring current values or voltage values of the effective points Iin and Iout, and usually refers to measuring the current values;


step S300: generating a threshold: generating a threshold according to measurement results in the step S200, including:


step S301: generating a critical abnormal alarm time threshold t1,


step S302: generating a critical defect alarm time threshold t2,


step S303: generating a non-critical abnormal electric leakage threshold t3;


step S400: randomly measuring an input current Iin i and an output current Iout i at the hidden portion of the electric transmission line;


step S500: randomly measuring an error δin 1 of the input current Iin i and an error δout 2 of the output current Iout i at the hidden portion of the electric transmission line; and


step S600: judging values of Iin i−Iout i and δin 1out 2, if Iin i−Iout i is greater than δin 1out 2, [formula 1];


generating a necessary remaining life number Δt21, wherein Δt21=t2−t1. [formula 2]


In the step S301, a judgment standard of the critical abnormal alarm time threshold t1 is that: if a current carrying capacity passing through an electric transmission line portion at a certain time exceeds an allowable current carrying capacity, then the time is the critical abnormal alarm time threshold t1. In the present invention, by judging whether the current carrying capacity passing through the electric transmission line portion at a certain time exceeds the allowable current carrying capacity, if the current carrying capacity exceeds the allowable current carrying capacity, the time is the critical abnormal alarm time threshold t1, compared with the prior art, the alarm time threshold t1 is far lower than 20%, which is more scientific, and an alarm is capable of being given for an abnormal situation in time, which is convenient for trouble clearing to reduce unnecessary losses.


In the step S302, a calculation formula of the critical defect alarm time threshold t2 is:






t
2
=t
1(1+b)  [formula 3]


in the formula 3, t1 is the critical abnormal alarm time threshold; and a value of b is selected based on a line type of the electric transmission line and LSL to USL curves, a is a standard deviation in the LSL to USL curves, and the value of b is 0.75σ to 2.75σ.


It can be seen from the formula 2 and the formula 3 that, the necessary remaining life number Δt21 is determined by the critical defect alarm time threshold t2 and the critical abnormal alarm time threshold t1, which is related to the line type of the electric transmission line and the LSL to USL curves, and the present invention can predict the necessary remaining life of the electric device or system by randomly measuring the input current Iin i, the output current Iout i and the errors of the input and output currents.


In the step S303, a representation formula of the non-critical abnormal electric leakage threshold t3 is that: t3=Iin i−Iout iin 1out 2 [formula 4]


in the above formula 4, the representation means that: at the time of electric leakage, a difference between the input current Iin i and the output current Iout i at the hidden portion of the electric transmission line randomly measured is greater than a sum of the error δin 1 of the input current Iin i and the error δout 2 of the output current Iout i at the hidden portion of the electric transmission line randomly measured; and


the time is the non-critical abnormal electric leakage threshold t3.


When the electric leakage occurs, the non-critical abnormal electric leakage threshold t3 may be reached, and the non-critical abnormal electric leakage threshold t3 is a precondition for generating the necessary remaining life number Δt21.


In the step S600, the generating the necessary remaining life number Δt21 further includes: counting the necessary remaining life number Δt21 obtained according to the formula 2 to generate (μ21, σ21), and obtaining that the necessary remaining life number Δt21 is (μ21−Kσ21) [formula 5]


in the above formula 5, K represents a standard deviation coefficient of normal distribution of Δt21, and a value of K ranges from 1 to 6;


σ21 represents a variance of the necessary remaining life number Δt21; and


μ21 represents a true value of the necessary remaining life number Δt21.


The present invention further provides a device for improving current transmission reliability, which includes:


a central processing unit;


an input current detection module configured for detecting an input current Iin i at a hidden portion of an electric transmission line randomly measured;


an output current detection module configured for detecting an output current Iout i at the hidden portion of the electric transmission line randomly measured;


a first sensor configured for feeding back the input current detected by the input current detection module to the central processing unit;


a second sensor configured for feeding back the output current detected by the output current detection module to the central processing unit;


a first alarm device configured for, when the input current Iin i or the output current Iout i exceeds the allowable current carrying capacity, giving an alarm under control of the central processing unit; and


a second alarm device configured for, in a case of the critical abnormal alarm time threshold t1, if the critical defect alarm time threshold t2 satisfies a formula t2=t1(1+b), giving an alarm under control of the central processing unit, wherein a value of b is selected based on a line type of the electric transmission line and LSL to USL curves, σ is a standard deviation in the LSL to USL curves, and the value of b ranges from 0.75σ to 2.75σ.


In the device of the present invention, the input current detection module, the output current detection module, the first sensor, the second sensor, the first alarm device and the second alarm device all work independently and do not affect each other, so that there is no technical problem of cross liability caused by overlapping detection methods or data.


Embodiment 1

Electricity consumption of a certain department of an enterprise in Dongguan, Guangdong is often in a critical state, and power cut inside and outside a tube often occurs, which has affected the production and life of the enterprise. Specific steps for quantifying a necessary remaining life by a method in the embodiment are as follows.


1. Selection of Effective Points


As shown in FIG. 2, main switch outlets of a certain department are selected as the effective points.


2. Performance of Technical Measurement


A clip-on ammeter of ZOYI ZT-QB9 is used to simultaneously perform technical measurement on selected effective points of an induced current of a 10 square copper core according to a Chinese national standard GB/T 4706.1-2005. In the embodiment, the induced current is measured through the clip-on ammeter.









TABLE 1





Chinese national standard GB/T 4706.1-2005
















Allowable long-term load current of 2.5 square copper core
16 A to 25 A


Allowable long-term load current of 10.0 square copper core
50 A to 63 A









3. Generation of Threshold


According to the Chinese national standard GB/T 4706.1-2005, values of the allowable long-term load current of the 10 square copper core are shown in Table 2.












Core numbers and values of allowable long-term


load current of copper core











Allowable current


Cross section
Load power
carrying capacity (A)











of copper
(KW) = voltage
Single-core
Twin-core
Three-core


core (mm2)
* current
cable
cable
cable





10

63
56
50









A single-core cable with a cross section area of 10 mm2 is taken as an example, which has an allowable current carrying capacity of 63 A.


When t1=63 A, a critical abnormal alarm time threshold t1 is generated (when t1>63 A, the time is an abnormal alarm time).


According to LSL to USL curves in FIG. 3 and Table 3, t2=1.2 t1=75 A, and at the time, a critical defect alarm time threshold t2 is generated (when t2>75 A, the time is a defect alarm time).









TABLE 3







Safe current carrying capacity comparison table of overhead line









Temperature













35° C.
40° C.
45° C.
50° C.
55° C.








Line model
Current carrying capacity/A















LJ-16
93
84
76
66
53


LGJ-16
97
88
79
68
56


LJ-25
120
109
98
85
69


LGJ-25
124
112
101
88
71


LJ-35
150
136
123
106
87


LGJ-35
150
136
123
106
87


LJ-50
190
172
155
134
110


LGJ-50
195
177
159
138
113


LJ-70
234
212
191
166
135


LGJ-70
242
220
198
171
140


LJ-95
290
263
237
205
168


LGJ-95
295
268
241
209
171


LJ-120
330
300
270
234
191


LGJ-120
335
304
274
237
194


LJ-150
388
353
318
275
255


LGJ-150
393
357
322
279
227


LJ-180
440
400
360
312
255


LGJ-185
450
409
369
319
261


LGJ-240
540
491
442
383
313









4. Generation of Necessary Remaining Life Number Δt21


Under confidence of t21=t2−t1, (μ21-3σ21) may be counted based on a “±kσ principle” by ±6σ through a formula Δt21=t2−t1 [formula 2] in the embodiment. See Table 4 for details.









TABLE 4







Date table of Δt21 when t1 = 0 (minutes)














Serial


Serial





number
t2
Δt21 = t2-t1
number
t2
Δt21 = t2-t1


















1
33
33
15
43
43



2
38
38
16
42
42



3
42
42
17
40
40



4
35
35
18
37
37



5
36
36
19
42
42



6
41
41
20
39
39



7
37
37
21
41
41



8
42
42
22
42
42



9
39
39
23
40
40



10
42
42
24
37
37



11
41
41
25
39
39



12
38
38
26
43
43



13
44
44
27
42
42



14
35
35










A perfect necessary remaining life number Δt21 is obtained as follows:





σ21=2.86





μ21=39.4





μ21−kσ21


When k=3,


the above formula is 39.4−3×2.86=30.82





Δt21=30.82 minutes≈30 minutes (rounding)


The embodiment solves a problem that a safe remaining life of an alarm current cannot be quantified in the prior art, which means that the current may be predicted statistically to be not failed within 30 minutes. When the current exceeds the abnormal time, the treatment is completed within 30 minutes.


5. Blocking Legislation


In the embodiment, a foreground adopts a form of enterprise WeChat, which solves a blocking legislation problem after the foreground adopts a decentralized distributed ledger mode; and a background adopts a blockchain mode.


Embodiment 2

An electric leakage phenomenon of a non-critical hidden project occurred in an enterprise in Dongguan, Guangdong, which has constituted a potential safety hazard. Specific steps of giving an alarm to the electric leakage by a method in the embodiment are as follows.


1. Selection of Effective Points


As shown in FIG. 4, effective points are selected outside inlet and outlet ends of a hidden project.


2. Performance of Technical Measurement


A measuring instrument in the embodiment is a clip-on ammeter of ZOYI ZT-QB9, with an instrument precision of ±(2%+3). Technical measurement is simultaneously performed on selected effective points of an induced current of a 2.5 mm2 copper wire. In the embodiment, the induced current is measured through the clip-on ammeter. Specific current sample data are shown in Table 5:









TABLE 5







0.1 KW resistance value












Serial number
Iin
Iout
Iin-Iout
















1
0.29
0.29
0



2
0.28
0.30
−0.02



3
0.24
0.28
−0.04



4
0.24
0.24
0



5
0.24
0.28
−0.04



6
0.24
0.24
0



7
0.24
0.23
0.01



8
0.24
0.24
0



9
0.24
0.24
0



10
1.28
0.25
1.03



11
0.24
0.24
0



12
0.24
0.24
0



13
0.24
0.24
0



14
0.24
0.24
0



15
0.24
0.24
0



16
0.24
0.24
0



17
0.24
0.24
0



18
0.24
0.24
0



19
0.24
0.24
0



20
0.28
0.28
0



21
0.28
0.28
0



22
0.24
0.28
−0.04



23
0.29
0.29
0



24
0.28
0.28
0



25
0.28
0.28
0










In a case of electric leakage:





when t3=Iin i−Iout iin 1out 2






I
in i
−I
out i=1.28−0.25−1.03





δin 1out 2=(1.28×2%+0.03)+(0.25×2%+0.03)=0.0906





1.03>0.0906


An alarm of electric leakage is given at t3.


In the embodiment, taking measurement of 0.1 KW resistance value as an example, in a case of electric leakage, an alarm should be given in time, and countermeasures should be taken.


The above embodiments only express several embodiments of the present invention, and the descriptions thereof are specific and detailed, but they cannot be understood as limiting the scope of protection of the present invention. It shall be pointed out that those of ordinary skills in the art may further make several modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the appended claims.

Claims
  • 1. A method for improving current transmission reliability, comprising: step S100: selecting effective points: respectively selecting an input current effective point Iin and an output current effective point Iout at two ends of a hidden portion of an electric transmission line;step S200: performing technical measurement: performing technical measurement on the effective points Iin and Iout selected in the step S100;step S300: generating a threshold: generating a threshold according to measurement results in the step S200, comprising:step S301: generating a critical abnormal alarm time threshold t1,step S302: generating a critical defect alarm time threshold t2,step S303: generating a non-critical abnormal electric leakage threshold t3;step S400: randomly measuring an input current Iin i and an output current Iout i at the hidden portion of the electric transmission line;step S500: randomly measuring an error δin 1 of the input current Iin i and an error δout 2 of the output current Iout i at the hidden portion of the electric transmission line; andstep S600: judging values of Iin i−Iout i and δin 1+δout 2,if Iin i−Iout i is greater than δin 1+δout 2, [formula 1]generating a necessary remaining life number Δt21, wherein Δt21=t2−t1. [formula 2]
  • 2. The method according to claim 1, wherein in the step S301, a judgment standard of the critical abnormal alarm time threshold t1 is that: if a current carrying capacity passing through an electric transmission line portion at a certain time exceeds an allowable current carrying capacity, then the time is the critical abnormal alarm time threshold t1.
  • 3. The method according to claim 1, wherein in the step S302, a calculation formula of the critical defect alarm time threshold t2 is: t2=t1(1+b) [formula 3] in the formula 3, t1 is the critical abnormal alarm time threshold; anda value of b is selected based on a line type of the electric transmission line and LSL to USL curves, σ is a standard deviation in the LSL to USL curves, and the value of b is 0.75σ to 2.75σ.
  • 4. The method according to claim 1, wherein in the step S303, a representation formula of the non-critical abnormal electric leakage threshold t3 is that: t3=Iin i−Iout i>δin 1+δout 2 [formula 4] in the formula 4, the representation means that: at the time of electric leakage, a difference between the input current Iin i and the output current Iout i at the hidden portion of the electric transmission line randomly measured is greater than a sum of the error δin 1 of the input current Iin i and the error δout 2 of the output current Iout i at the hidden portion of the electric transmission line randomly measured; andthe time is the non-critical abnormal electric leakage threshold t3.
  • 5. The method according to claim 1, wherein in the step S600, the generating the necessary remaining life number Δt21 further comprises: counting the necessary remaining life number Δt21 obtained according to the formula 2 to generate (μ21, σ21), and obtaining that the necessary remaining life number Δt21 is (μ21−Kσ21) [formula 5] in the formula 5, K represents a standard deviation coefficient of normal distribution of Δt21, and a value of K ranges from 1 to 6;σ21 represents a variance of the necessary remaining life number Δt21; andμ21 represents a true value of the necessary remaining life number Δt21.
  • 6. A device for improving current transmission reliability, comprising: a central processing unit;an input current detection module configured for detecting an input current Iin i at a hidden portion of an electric transmission line randomly measured;an output current detection module configured for detecting an output current Iout i at the hidden portion of the electric transmission line randomly measured;a first sensor configured for feeding back the input current detected by the input current detection module to the central processing unit;a second sensor configured for feeding back the output current detected by the output current detection module to the central processing unit;a first alarm device configured for, when the input current Iin i or the output current Iout i exceeds the allowable current carrying capacity, giving an alarm under control of the central processing unit; anda second alarm device configured for, in a case of the critical abnormal alarm time threshold t1, if the critical defect alarm time threshold t2 satisfies a formula t2=t1(1+b), giving an alarm under control of the central processing unit, wherein a value of b is selected based on a line type of the electric transmission line and LSL to USL curves, σ is a standard deviation in the LSL to USL curves, and the value of b ranges from 0.75σ to 2.75 σ.
Priority Claims (1)
Number Date Country Kind
202110928383.9 Aug 2021 CN national