Method and device for evaluating electrical life of high-capacity vacuum circuit breaker

Abstract

The invention discloses a method and device for evaluating the electrical life of a high-capacity vacuum circuit breaker, and belongs to the technical field of vacuum circuit breakers, and the method comprises the steps: calculating the energy flow cumulant of a contact according to the obtained constant value, arcing time and arc current waveform related to a contact material; calculating the ablation deformation quantity of the contact blade according to the pre-obtained contact closing holding force and over travel; according to the obtained contact energy flow threshold value and the obtained contact blade ablation deformation threshold value, the residual electrical life of the high-capacity vacuum circuit breaker is calculated in combination with the contact energy flow cumulant and the contact blade ablation deformation quantity; judging whether the obtained residual electrical life of the high-capacity vacuum circuit breaker is lower than a set value or not, if not, repeating the steps, and if yes, alarming and ending; according to the invention, through comprehensive analysis of multiple parameters, evaluation of the electrical life of the high-capacity vacuum circuit breaker is realized according to an influence rule of different parameters on the electrical life of the vacuum circuit breaker.

Description

Technical Field

[0001] The present invention relates to a method and a device for evaluating the electrical life of a large-capacity vacuum circuit breaker, and belongs to the technical field of vacuum circuit breakers. Background Art

[0002] SF6 gas, one of the six major greenhouse gases, is currently widely used in high-voltage power switchgear. With the "dual carbon" goals, reducing SF6 gas usage has become a key environmental goal in the power switchgear sector. my country's wind power generation capacity is rapidly increasing, and long-distance offshore power transmission, in particular, creates an urgent need for technology. Vacuum circuit breakers offer advantages such as environmental friendliness and maintenance-free operation. However, the increasing interrupting capacity of vacuum circuit breakers significantly impacts their electrical lifespan. Evaluating the electrical lifespan of large-capacity vacuum circuit breakers has become a key technical challenge in high-voltage vacuum switchgear. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method and device for evaluating the electrical life of a large-capacity vacuum circuit breaker. By comprehensive analysis of multiple parameters and according to the influence of different parameters on the electrical life of the vacuum circuit breaker, the electrical life of the large-capacity vacuum circuit breaker can be evaluated.

[0004] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0005] In a first aspect, the present invention provides a method for evaluating the electrical life of a large-capacity vacuum circuit breaker, comprising:

[0006] The accumulated contact energy flow is calculated based on the pre-acquired constant values related to the contact material, arcing time and arc current waveform;

[0007] Calculate the contact erosion deformation based on the contact closing holding force and overtravel obtained in advance;

[0008] The remaining electrical life of the large-capacity vacuum circuit breaker is calculated based on the pre-acquired contact energy flow threshold and contact piece ablation deformation threshold, combined with the cumulative contact energy flow and contact piece ablation deformation;

[0009] It is determined whether the remaining electrical life of the large-capacity vacuum circuit breaker is lower than the set value. If it is not lower than the set value, the above steps are repeated. If it is lower than the set value, an alarm is issued and the process ends.

[0010] Furthermore, the calculation formula of the contact energy flow threshold is:

[0011] ;

[0012] Where: P 1thre is the contact energy flow threshold, NN is the rated short-circuit breaking current breaking times, α and β are constants related to the contact material parameters, t N is the rated maximum arcing time of the vacuum circuit breaker, i N It is the instantaneous value of the rated short-circuit breaking current of the vacuum circuit breaker.

[0013] Furthermore, the calculation formula of the contact piece ablation deformation threshold is:

[0014] ;

[0015] Where: P 2thre is the ablation deformation threshold of the contact piece, γ is a constant related to the material parameters of the contact piece, F N is the initial value of the contact closing holding force, L N is the initial value of overtravel, F min L is the minimum value allowed for the contact closing holding force, min This is the minimum value allowed for overtravel.

[0016] Furthermore, the cumulative amount of contact energy flow is the sum of the contact energy flows during all previous opening and closing processes of the vacuum circuit breaker, and the specific calculation formula is:

[0017] ;

[0018] Where: P1 is the cumulative amount of contact energy flow, N is the number of short-circuit current interruptions, α and β are constants related to the contact material parameters, t1 is the starting time of the vacuum circuit breaker arc, t2 is the ending time of the vacuum circuit breaker arc, i i It is the instantaneous value of the breaking current of the vacuum circuit breaker.

[0019] Furthermore, the calculation formula for the ablation deformation of the contact piece is:

[0020] ;

[0021] Where: P2 is the ablation deformation of the contact piece, γ is a constant related to the material parameters of the contact piece, F N is the initial value of the contact closing holding force, L N is the initial value of overtravel, F i is the contact closing holding force after the i-th current breaking, L i It is the overtravel after the i-th current breaking.

[0022] Furthermore, the calculation formula for the remaining electrical life of the large-capacity vacuum circuit breaker is:

[0023] ;

[0024] Among them: S is the remaining electrical life, P1 is the cumulative amount of contact energy flow, P 1threis the contact energy flow threshold, P2 is the contact piece ablation deformation, P 2thre is the ablation deformation threshold of the contact piece, k1 and k2 are the proportions of the two electrical lifespans to the comprehensive remaining electrical life, and k1+k2=1 is satisfied.

[0025] Furthermore, the method also includes: when the remaining battery life is less than 20%, an alarm is issued; when the remaining battery life is not less than 20%, a cycle step is entered until the remaining battery life is less than 20%.

[0026] In a second aspect, the present invention provides a large-capacity vacuum circuit breaker electrical life assessment device, comprising:

[0027] The first calculation module is used to calculate the cumulative amount of contact energy flow based on the constant values, arcing time and arc current waveform related to the contact material obtained in advance;

[0028] A second calculation module is used to calculate the contact piece ablation deformation amount based on the contact closing holding force and overtravel obtained in advance;

[0029] The third calculation module is used to calculate the remaining electrical life of the large-capacity vacuum circuit breaker based on the pre-acquired contact energy flow threshold and contact piece ablation deformation threshold, combined with the accumulated contact energy flow and the contact piece ablation deformation;

[0030] The evaluation module is used to determine whether the remaining electrical life of the large-capacity vacuum circuit breaker is lower than a set value. If it is not lower than the set value, the above steps are repeated. If it is lower than the set value, an alarm is issued and the process ends.

[0031] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of any of the aforementioned methods when executed by a processor.

[0032] In a fourth aspect, the present invention provides a computer device, comprising:

[0033] Memory, used to store computer programs / instructions;

[0034] A processor is configured to execute the computer program / instructions to implement the steps of any of the aforementioned methods.

[0035] In a fifth aspect, the present invention provides a computer program product, comprising a computer program / instruction, which implements the steps of any of the aforementioned methods when executed by a processor.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] The present invention provides a method and device for assessing the electrical life of large-capacity vacuum circuit breakers. By statistically analyzing arcing time, arc current, and contact material parameters, these devices establish electrical life assessment parameters based on contact gap energy erosion. By inferring contact erosion thickness based on contact closing retention and overtravel variations, these devices establish electrical life assessment parameters based on contact energy flow erosion and contact erosion deformation. By combining these two sets of parameters, an effective and reliable prediction of the electrical life of large-capacity vacuum circuit breakers can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a flow chart of a method for evaluating the electrical life of a large-capacity vacuum circuit breaker provided by an embodiment of the present invention;

[0039] Figure 2 1 is a diagram showing a relationship curve between contact energy flow parameters and electrical life provided by an embodiment of the present invention;

[0040] Figure 3 1 is a schematic diagram of a curve showing the relationship between the ablation deformation and electrical life of a contact piece provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0042] Example 1: This example introduces a method for evaluating the electrical life of a large-capacity vacuum circuit breaker, including:

[0043] The accumulated contact energy flow is calculated based on the pre-acquired constant values related to the contact material, arcing time and arc current waveform;

[0044] Calculate the contact erosion deformation based on the contact closing holding force and overtravel obtained in advance;

[0045] The remaining electrical life of the large-capacity vacuum circuit breaker is calculated based on the pre-acquired contact energy flow threshold and contact piece ablation deformation threshold, combined with the cumulative contact energy flow and contact piece ablation deformation;

[0046] It is determined whether the remaining electrical life of the large-capacity vacuum circuit breaker is lower than the set value. If it is not lower than the set value, the above steps are repeated. If it is lower than the set value, an alarm is issued and the process ends.

[0047] like Figure 1 As shown, the application process of the large-capacity vacuum circuit breaker electrical life assessment method provided in this embodiment specifically involves the following steps:

[0048] The first step is to obtain the energy flow parameters of the large-capacity vacuum circuit breaker contacts, and according to the relationship curve between the energy flow parameters and electrical life accumulated from existing experiments (such as Figure 2 As shown in the figure), calculate the contact energy flow threshold; obtain the mechanical parameters of the circuit breaker, and calculate the relationship curve between the contact piece ablation deformation and electrical life according to the existing experimental accumulation (as shown in the figure). Figure 3 As shown), determine the ablation deformation threshold of the contact piece;

[0049] The second step is to obtain the contact material parameters and determine the constant values related to the contact material according to the contact material parameters; obtain the arc current waveform during the arcing process and calculate the arcing time;

[0050] The third step is to obtain the contact closing holding force and overtravel after the arcing process;

[0051] The fourth step is to calculate and accumulate the cumulative contact energy flow according to the constant values related to the contact material parameters, arcing time and arc current waveform obtained in the second step;

[0052] Step 5: Calculate the contact erosion deformation based on the contact closing holding force and overtravel obtained in Step 3.

[0053] Step 6: Calculate the remaining electrical life of the large-capacity vacuum circuit breaker based on the contact energy flow threshold and contact piece ablation deformation threshold obtained in the first step, the contact energy flow accumulation obtained in the fourth step, and the contact piece ablation deformation obtained in the fifth step;

[0054] The seventh step is to determine whether the remaining electrical life of the large-capacity vacuum circuit breaker obtained in the sixth step is lower than the set value; if it is not lower than the set value, a new cycle is started from the second step; if it is lower than the set value, an alarm is issued and the cycle ends.

[0055] In the first step, the calculation formula of the contact energy flow threshold is:

[0056] ;

[0057] In the formula: P 1thre is the contact energy flow threshold, N N is the rated short-circuit breaking current breaking times, α and β are constants related to the contact material parameters, t N is the rated maximum arcing time of the vacuum circuit breaker, i N It is the instantaneous value of the rated short-circuit breaking current of the vacuum circuit breaker.

[0058] In the first step, the calculation formula for the contact piece ablation deformation threshold is:

[0059] ;

[0060] In the formula: P 2threis the ablation deformation threshold of the contact piece, γ is a constant related to the material parameters of the contact piece, F N is the initial value of the contact closing holding force, L N is the initial value of overtravel, F min L is the minimum value allowed for the contact closing holding force, min This is the minimum value allowed for overtravel.

[0061] In the second step, the constant values related to the contact material are obtained based on actual engineering applications and type tests of different models of vacuum circuit breakers; the arc current waveform is obtained through the current acquisition component in the vacuum circuit breaker; and the arc burning time is obtained by calculating the arc start time and arc end time.

[0062] In the third step, the constant values related to the contact material are obtained based on actual engineering applications and type tests of different models of vacuum circuit breakers; the contact closing holding force and overtravel are obtained through a vacuum circuit breaker force-displacement curve testing device.

[0063] In the fourth step, the cumulative amount of contact energy flow is the sum of the contact energy flow during all previous opening and closing processes of the vacuum circuit breaker. The specific calculation formula is:

[0064] ;

[0065] In the formula: P1 is the cumulative amount of contact energy flow, N is the number of short-circuit current interruptions, α and β are constants related to the contact material parameters, t1 is the starting time of the vacuum circuit breaker arc, t2 is the ending time of the vacuum circuit breaker arc, i i It is the instantaneous value of the breaking current of the vacuum circuit breaker.

[0066] In the fifth step, the specific calculation formula for the contact piece ablation deformation is:

[0067] ;

[0068] In the formula: P2 is the ablation deformation of the contact piece, γ is a constant related to the material parameters of the contact piece, F N is the initial value of the contact closing holding force, L N is the initial value of overtravel, F i is the contact closing holding force after the i-th current breaking, L i It is the overtravel after the i-th current breaking.

[0069] In the sixth step, the remaining electrical life of the large-capacity vacuum circuit breaker is calculated by combining the accumulated contact energy flow and the ablation deformation of the contact piece. The specific calculation formula is:

[0070] ;

[0071] In the formula: S is the remaining electrical life, P1 is the cumulative amount of contact energy flow, P1thre is the contact energy flow threshold, P2 is the contact piece ablation deformation, P 2thre is the ablation deformation threshold of the contact piece, k1 and k2 are the proportions of the two electrical lifespans to the comprehensive remaining electrical life, and k1+k2=1 is satisfied.

[0072] In the seventh step, when the remaining battery life is less than 20%, an alarm is issued; when the remaining battery life is not less than 20%, the process goes to step 2 and the detection is repeated until the remaining battery life is less than 20%.

[0073] This embodiment discloses a method for assessing the electrical life of large-capacity vacuum circuit breakers. By statistically analyzing arcing time, arc current, and contact material parameters, electrical life assessment parameters for large-capacity vacuum circuit breakers are established from the perspective of contact gap energy erosion. Contact erosion thickness is estimated by analyzing contact closing retention force and overtravel variations, and electrical life assessment parameters for large-capacity vacuum circuit breakers are established from the perspectives of contact energy flow erosion and contact erosion deformation. Combining these two sets of parameters enables effective and reliable prediction of the electrical life of large-capacity vacuum circuit breakers.

[0074] Embodiment 2: This embodiment provides a large-capacity vacuum circuit breaker electrical life assessment device, comprising:

[0075] The first calculation module is used to calculate the cumulative amount of contact energy flow based on the constant values, arcing time and arc current waveform related to the contact material obtained in advance;

[0076] A second calculation module is used to calculate the contact piece ablation deformation amount based on the contact closing holding force and overtravel obtained in advance;

[0077] The third calculation module is used to calculate the remaining electrical life of the large-capacity vacuum circuit breaker based on the pre-acquired contact energy flow threshold and contact piece ablation deformation threshold, combined with the accumulated contact energy flow and the contact piece ablation deformation;

[0078] The evaluation module is used to determine whether the remaining electrical life of the large-capacity vacuum circuit breaker is lower than a set value. If it is not lower than the set value, the above steps are repeated. If it is lower than the set value, an alarm is issued and the process ends.

[0079] The specific functional implementation of each of the above modules can be found in the relevant content of the method in Example 1 and will not be elaborated on here.

[0080] Example 3: This embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the steps of any one of the methods described in Example 1 are implemented.

[0081] Embodiment 4: This embodiment provides a computer device, including:

[0082] Memory, used to store computer programs / instructions;

[0083] A processor, configured to execute the computer program / instructions to implement the steps of any one of the methods described in Example 1.

[0084] Example 5: This embodiment provides a computer program product, including a computer program / instruction, which implements the steps of any method described in Example 1 when executed by a processor.

[0085] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

[0086] Those skilled in the art will appreciate that embodiments of the present disclosure may be provided as methods, systems, or computer program products. Thus, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROMs, optical storage, etc.) containing computer-usable program code.

[0087] The present disclosure is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present disclosure. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0088] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0089] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure and are not intended to limit its scope of protection. Although the present disclosure has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that after reading the present disclosure, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the scope of protection of the disclosed claims to be approved.

Claims

1. A method for evaluating the electrical life of a large-capacity vacuum circuit breaker, characterized in that: include: The accumulated contact energy flow is calculated based on the pre-acquired constant values related to the contact material, arcing time and arc current waveform; Calculate the contact erosion deformation based on the contact closing holding force and overtravel obtained in advance; The remaining electrical life of the large-capacity vacuum circuit breaker is calculated based on the pre-acquired contact energy flow threshold and contact piece ablation deformation threshold, combined with the cumulative contact energy flow and contact piece ablation deformation; It is determined whether the remaining electrical life of the large-capacity vacuum circuit breaker is lower than the set value. If it is not lower than the set value, the above steps are repeated. If it is lower than the set value, an alarm is issued and the process ends.

2. The electrical life evaluation method for a large-capacity vacuum circuit breaker according to claim 1, characterized in that: The calculation formula of the contact energy flow threshold is: ； Where: P 1thre is the contact energy flow threshold, N N is the rated short-circuit breaking current breaking times, α and β are constants related to the contact material parameters, t N is the rated maximum arcing time of the vacuum circuit breaker, i N It is the instantaneous value of the rated short-circuit breaking current of the vacuum circuit breaker.

3. The electrical life evaluation method for a large-capacity vacuum circuit breaker according to claim 2, characterized in that: The calculation formula of the contact piece ablation deformation threshold is: ； Where: P 2thre is the ablation deformation threshold of the contact piece, γ is a constant related to the material parameters of the contact piece, F N is the initial value of the contact closing holding force, L N is the initial value of overtravel, F min L is the minimum value allowed for the contact closing holding force, min This is the minimum value allowed for overtravel.

4. The electrical life evaluation method for a large-capacity vacuum circuit breaker according to claim 3, characterized in that: The cumulative contact energy flow is the sum of the contact energy flows during all previous opening and closing processes of the vacuum circuit breaker. The specific calculation formula is: ； Where: P1 is the cumulative amount of contact energy flow, N is the number of short-circuit current interruptions, α and β are constants related to the contact material parameters, t1 is the starting time of the vacuum circuit breaker arc, t2 is the ending time of the vacuum circuit breaker arc, i i It is the instantaneous value of the breaking current of the vacuum circuit breaker.

5. The electrical life evaluation method for a large-capacity vacuum circuit breaker according to claim 4, characterized in that: The calculation formula of the contact piece ablation deformation is: ； Where: P2 is the ablation deformation of the contact piece, γ is a constant related to the material parameters of the contact piece, F N is the initial value of the contact closing holding force, L N is the initial value of overtravel, F i is the contact closing holding force after the i-th current breaking, L i It is the overtravel after the i-th current breaking.

6. The electrical life evaluation method for a large-capacity vacuum circuit breaker according to claim 5, characterized in that: The calculation formula for the remaining electrical life of the large-capacity vacuum circuit breaker is: ； Among them: S is the remaining electrical life, P1 is the cumulative amount of contact energy flow, P 1thre is the contact energy flow threshold, P2 is the contact piece ablation deformation, P 2thre is the ablation deformation threshold of the contact piece, k1 and k2 are the proportions of the two electrical lifespans to the comprehensive remaining electrical life, and k1+k2=1 is satisfied.

7. The electrical life evaluation method for a large-capacity vacuum circuit breaker according to claim 1, characterized in that: The method further includes: when the remaining battery life is less than 20%, an alarm is issued; when the remaining battery life is not less than 20%, a cycle step is entered until the remaining battery life is less than 20%.

8. A large-capacity vacuum circuit breaker electrical life evaluation device, characterized in that: include: The first calculation module is used to calculate the cumulative amount of contact energy flow based on the constant values, arcing time and arc current waveform related to the contact material obtained in advance; A second calculation module is used to calculate the contact piece ablation deformation amount based on the contact closing holding force and overtravel obtained in advance; The third calculation module is used to calculate the remaining electrical life of the large-capacity vacuum circuit breaker based on the pre-acquired contact energy flow threshold and contact piece ablation deformation threshold, combined with the accumulated contact energy flow and the contact piece ablation deformation; The evaluation module is used to determine whether the remaining electrical life of the large-capacity vacuum circuit breaker is lower than a set value. If it is not lower than the set value, the above steps are repeated. If it is lower than the set value, an alarm is issued and the process ends.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer device, characterized in that: include: Memory, used to store computer programs / instructions; A processor configured to execute the computer program / instructions to implement the steps of the method according to any one of claims 1 to 7.

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