A rapid detection method for mechanical characteristics of high-voltage circuit breakers

Abstract

The present invention relates to a method for quickly detecting the mechanical characteristics of a high-voltage circuit breaker, which comprises the following steps: S1, collecting a current signal of a high-voltage circuit breaker coil to obtain a time-current current curve; S2, synchronously collecting a vibration signal of an arc extinguishing chamber body of the high-voltage circuit breaker to obtain a time-acceleration curve of the arc extinguishing chamber body vibration; S3, synchronously collecting a contact stroke signal of the high-voltage circuit breaker to obtain a contact stroke curve of the time-contact stroke signal; S4, mapping the action moment of the high-voltage circuit breaker and the connection moment of the dynamic and static arc contacts onto the contact stroke curve to obtain a mechanical characteristic value of the high-voltage circuit breaker. The above technical solution is used to realize rapid and effective detection of the mechanical characteristics.

Description

Technical Field

[0001] The present invention relates to the field of high-voltage electrical equipment state detection, and in particular to a method for quickly detecting mechanical characteristics of a high-voltage circuit breaker. Background Art

[0002] High-voltage circuit breakers are important control and protection equipment in power systems. Their main functions are to cut off and connect load circuits, as well as cut off fault circuits to prevent accidents from expanding and ensure the safe operation of power systems.

[0003] High-voltage circuit breakers have numerous mechanical components and a complex structure, resulting in a high mechanical failure rate. Actual operational statistics also show that mechanical failure is the primary cause of high-voltage circuit breaker failure. By testing the mechanical characteristics of the circuit breaker's opening and closing motions, the mechanical condition of the circuit breaker can be effectively determined, potential hazards can be promptly identified, and reliable operation of the high-voltage circuit breaker can be ensured. However, the current on-site mechanical characteristic testing process for high-voltage circuit breakers is cumbersome and can only be performed during power outages. This is because current testing methods require obtaining arc chamber contact shift signals (i.e., contact connection and disconnection signals) to ultimately determine the mechanical characteristics of the high-voltage circuit breaker (combined with contact travel signals and coil current signals). Acquiring these contact shift signals is a tedious task: 1) For in-cabinet circuit breakers, the circuit breaker must be removed from the cabinet before connecting the auxiliary conductive circuit to obtain the contact shift signal; 2) For outdoor circuit breakers, the disconnectors on both sides of the circuit breaker must first be deactivated, followed by grounding wires and connecting the auxiliary conductive circuit to obtain the contact shift signal. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the present invention provides a method for quickly and effectively detecting the mechanical characteristics of a high-voltage circuit breaker by detecting the vibration signal of the arc extinguishing chamber body of the high-voltage circuit breaker, extracting the contact connection and disconnection moments therefrom, and combining the contact travel signal and the coil current signal.

[0005] A method for quickly detecting the mechanical characteristics of a high-voltage circuit breaker of the present invention adopts the following technical solutions:

[0006] S1. Collect the current signal of the high-voltage circuit breaker coil and obtain the time-current curve;

[0007] S2. synchronously collect vibration signals of the arc extinguishing chamber body of the high-voltage circuit breaker to obtain a time-acceleration curve of the arc extinguishing chamber body vibration;

[0008] S3. synchronously collect the high-voltage circuit breaker contact travel signal to obtain a contact travel curve of the time-contact travel signal;

[0009] S4. Mapping the high-voltage circuit breaker action moment and the dynamic and static arc contact connection moments onto a contact travel curve to obtain a mechanical characteristic value of the high-voltage circuit breaker.

[0010] Furthermore, the method for collecting the high-voltage circuit breaker coil current signal in step S1 is to directly clamp an open-type ammeter on the power line of the coil.

[0011] Furthermore, the method for collecting the vibration signal of the arc extinguishing chamber body of the high-voltage circuit breaker in step S2 is to adsorb the acceleration sensor directly below the porcelain column of the high-voltage circuit breaker.

[0012] Furthermore, the method for collecting the high-voltage circuit breaker contact stroke signal in step S3 is to install a displacement sensor on the external transmission arm of the operating mechanism.

[0013] Further, the step S4 includes the following steps:

[0014] S4-1, extracting the time corresponding to the first inflection point where the current starts to rise from the current curve of step S1 as the starting point of the high-voltage circuit breaker operation timing, recorded as T1;

[0015] S4-2, extracting the moment when the moving and static arc contacts are connected from the acceleration curve of step S2, that is, the starting moment of the second shock wave, recorded as T2;

[0016] S4-3, mark the highest position of the contact stroke on the contact stroke curve in step S3 as S max The final stable position of the stroke is S final ;

[0017] S4-4. Map the actuation time T1 of the high-voltage circuit breaker and the connection time T2 of the moving and static arc contacts onto the abscissa of the contact travel curve, and record the ordinates of the corresponding contact travel curves as S1 and S2, respectively.

[0018] S4-5. Calculate the mechanical characteristic values ​​of high voltage circuit breaker:

[0019] Total stroke = S final ;

[0020] Opening distance = S2-S1;

[0021] Overtravel = S final -S2;

[0022] Overshoot = S max -S final ;

[0023] Closing time = T2-T1;

[0024] Average closing speed = (S2-S1) / (T2-T1);

[0025] Closing synchronicity = the difference between the maximum T2 and the minimum T2 of the three phases.

[0026] Compared with the prior art, the present invention has the following beneficial effects: the vibration signal of the arc extinguishing chamber body during the operation of the high-voltage circuit breaker is used to extract the contact connection and separation moments, without the need for an external conductive circuit between the moving and static contacts, thereby greatly improving the detection efficiency; and because there is no need to inject current between the moving and static contacts, live detection can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings described herein are used to provide a further understanding of the present application, in which:

[0028] Figure 1 is a current curve diagram of time-current according to an embodiment of the present invention;

[0029] Figure 2 This is a time-acceleration curve of the arc extinguishing chamber body vibration according to an embodiment of the present invention;

[0030] Figure 3 A contact travel curve of a time-contact travel signal according to an embodiment of the present invention;

[0031] Figure 4 The high-voltage circuit breaker action moment of the current curve and the dynamic and static arc contact connection moments of the acceleration curve of the embodiment of the present invention are mapped to the contact stroke curve. DETAILED DESCRIPTION

[0032] See also Figure 1 As shown in the embodiment, a method for quickly detecting mechanical characteristics of a high-voltage circuit breaker includes the following steps:

[0033] S1. Collect the current signal of the high-voltage circuit breaker coil and obtain the time-current curve;

[0034] S2. Synchronously collect vibration signals of the arc extinguishing chamber body of the high-voltage circuit breaker to obtain a time-acceleration curve of the arc extinguishing chamber body vibration;

[0035] S3. synchronously collect the high-voltage circuit breaker contact travel signal to obtain a contact travel curve of the time-contact travel signal;

[0036] S4. Mapping the high-voltage circuit breaker action moment and the dynamic and static arc contact connection moments onto a contact travel curve to obtain a mechanical characteristic value of the high-voltage circuit breaker.

[0037] Furthermore, the method for collecting the high-voltage circuit breaker coil current signal in step S1 is to directly clamp an open-type ammeter on the power line of the coil.

[0038] Furthermore, the method for collecting the vibration signal of the arc extinguishing chamber body of the high-voltage circuit breaker in step S2 is to adsorb the acceleration sensor directly below the porcelain column of the high-voltage circuit breaker.

[0039] Furthermore, the method for collecting the high-voltage circuit breaker contact stroke signal in step S3 is to install a displacement sensor on the external transmission arm of the operating mechanism.

[0040] Further, the step S4 includes the following steps:

[0041] S4-1, extracting the time corresponding to the first inflection point where the current starts to rise from the current curve of step S1 as the starting point of the high-voltage circuit breaker operation timing, recorded as T1;

[0042] S4-2, extracting the moment when the moving and static arc contacts are connected from the acceleration curve of step S2, that is, the starting moment of the second shock wave, recorded as T2;

[0043] S4-3, mark the highest position of the contact stroke on the contact stroke curve in step S3 as S max The final stable position of the stroke is S final ;

[0044] S4-4. Map the actuation time T1 of the high-voltage circuit breaker and the connection time T2 of the moving and static arc contacts onto the abscissa of the contact travel curve, and record the ordinates of the corresponding contact travel curves as S1 and S2, respectively.

[0045] S4-5. Calculate the mechanical characteristic values ​​of high voltage circuit breaker:

[0046] Total stroke = S final ;

[0047] Opening distance = S2-S1;

[0048] Overtravel = S final -S2;

[0049] Overshoot = S max -S final ;

[0050] Closing time = T2-T1;

[0051] Average closing speed = (S2-S1) / (T2-T1);

[0052] Closing synchronicity = the difference between the maximum T2 and the minimum T2 of the three phases.

[0053] As shown in Table 1, the mechanical characteristics of the high-voltage circuit breaker are calculated using the key nodes of the signal detected by the above method:

[0054]

[0055]

[0056] Table 1

[0057] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for quickly detecting the mechanical characteristics of a high-voltage circuit breaker, characterized by: It includes the following steps: S1. Collect the current signal of the high-voltage circuit breaker coil and obtain the time-current curve; S2. Synchronously collect vibration signals of the arc extinguishing chamber body of the high-voltage circuit breaker to obtain a time-acceleration curve of the arc extinguishing chamber body vibration; S3. synchronously collect the high-voltage circuit breaker contact travel signal to obtain a contact travel curve of the time-contact travel signal; S4, mapping the high-voltage circuit breaker action time and the dynamic and static arc contact connection time to the contact stroke curve to obtain the mechanical characteristic value of the high-voltage circuit breaker; Step S4 includes the following steps: S4-1. Extract the time corresponding to the first inflection point where the current starts to rise from the current curve of step S1 as the starting point of the high-voltage circuit breaker operation timing, which is recorded as T 1; S4-2, extract the moment when the dynamic and static arc contacts are connected from the acceleration curve of step S2, that is, the starting moment of the second shock wave, and record it as T 2; S4-3, mark the highest position of the contact stroke on the contact stroke curve in step S3 as S max The final stable position of the stroke is S final ; S4-4, respectively set the above high voltage circuit breaker action time T 1 The moment when the moving and static arc contacts are connected T 2 is mapped to the abscissa of the contact travel curve, and the ordinates of the corresponding contact travel curves are recorded as S 1. S 2; S4-5. Calculate the mechanical characteristic values ​​of high voltage circuit breaker: Total travel = S final ; Opening distance = S 2 - S 1; Overtravel = S final - S 2; Overshoot = S max - S final ; Closing time = T 2 - T 1; Average closing speed = ( S 2 - S 1) / ( T 2 - T 1) ; Closing synchronism = three-phase maximum T 2 and minimum T A difference of 2.

2. A method for rapid detection of mechanical characteristics of a high-voltage circuit breaker according to claim 1, characterized in that: The method for collecting the high-voltage circuit breaker coil current signal in step S1 is to directly clamp an open-type ammeter on the power line of the coil.

3. A method for rapid detection of mechanical characteristics of a high-voltage circuit breaker according to claim 1, characterized in that: The method for collecting the vibration signal of the arc extinguishing chamber body of the high-voltage circuit breaker in step S2 is to adsorb the acceleration sensor directly below the porcelain column of the high-voltage circuit breaker.

4. A method for rapid detection of mechanical characteristics of a high-voltage circuit breaker according to claim 1, characterized in that: The method for collecting the high-voltage circuit breaker contact stroke signal in step S3 is to install a displacement sensor on the external transmission arm of the operating mechanism.

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