A method, apparatus, equipment and medium for analyzing the breaking risk of high-voltage circuit breakers.

Abstract

This invention discloses a method, apparatus, equipment, and medium for analyzing the breaking risk of high-voltage circuit breakers, used to assess the breaking failure risk of high-voltage circuit breakers and reduce the probability of breaking failure. The invention includes: obtaining the zero-crossing current change rate of the high-voltage circuit breaker under the influence of current harmonic components when a near-zone fault occurs; calculating the overall recovery voltage rise time of the high-voltage circuit breaker based on the zero-crossing current change rate; calculating the first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the disappearance of the line-side oscillation voltage based on the overall recovery voltage rise time; calculating the initial recovery voltage rise rate of the high-voltage circuit breaker using the overall recovery voltage rise time and the first peak voltage; determining whether the initial recovery voltage rise rate is greater than a preset threshold; if so, determining that the high-voltage circuit breaker has a breaking failure risk.

Description

Technical Field

[0001] This invention relates to the field of high-voltage circuit breaker technology, and in particular to a method, apparatus, equipment and medium for analyzing the breaking risk of high-voltage circuit breakers. Background Technology

[0002] High-voltage circuit breakers play a crucial role in power systems by closing, carrying, and interrupting the normal current of operating circuits and by closing, carrying, and interrupting the specified overload current within a specified time. When interrupting short-circuit current, an electric arc will be generated at the break point. After the arc is extinguished, a transient recovery voltage (TRV) of up to several hundred kilovolts will be generated between the break points immediately, affecting the successful interruption of the circuit breaker. Summary of the Invention

[0003] This invention provides a method, apparatus, equipment, and medium for analyzing the breaking risk of high-voltage circuit breakers, used to assess the breaking failure risk of high-voltage circuit breakers and reduce the probability of breaking failure of high-voltage circuit breakers.

[0004] This invention provides a method for analyzing the breaking risk of high-voltage circuit breakers, applicable to power systems; the method includes:

[0005] Obtain the rate of change of zero-crossing current of the high-voltage circuit breaker when a near-zone fault occurs under the influence of the current harmonic component;

[0006] The overall recovery voltage rise time of the high-voltage circuit breaker is calculated based on the zero-crossing current change rate.

[0007] The first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the line-side oscillation voltage disappears is calculated based on the overall recovery voltage rise time.

[0008] The initial recovery voltage rise rate of the high-voltage circuit breaker is calculated using the overall recovery voltage rise time and the first peak voltage.

[0009] Determine whether the initial recovery voltage rise rate is greater than a preset threshold. If so, determine that the high-voltage circuit breaker has a risk of failure to interrupt.

[0010] Optionally, the step of calculating the overall recovery voltage rise time of the high-voltage circuit breaker based on the zero-crossing current change rate includes:

[0011] Calculate the peak-to-peak voltage of the first peak of the oscillation voltage on the line side of the high-voltage circuit breaker;

[0012] Obtain the line surge impedance of the power system;

[0013] The rise time to the first peak voltage is calculated based on the zero-crossing current change rate, the first peak voltage, and the line impedance.

[0014] Obtain the line-side time delay of the high-voltage circuit breaker;

[0015] The overall recovery voltage rise time of the high-voltage circuit breaker is calculated using the line-side delay and the rise time.

[0016] Optionally, the step of calculating the first peak-to-peak voltage of the oscillation voltage on the line side of the high-voltage circuit breaker includes:

[0017] Obtain the near-zone fault breaking current, the rated short-circuit breaking current, and the rated voltage of the circuit breaker;

[0018] The first peak-to-peak voltage of the line-side oscillation voltage of the high-voltage circuit breaker is calculated using the near-zone fault breaking current, the rated short-circuit breaking current, and the rated voltage of the circuit breaker.

[0019] Optionally, the step of calculating the first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the disappearance of the line-side oscillation voltage, based on the overall recovery voltage rise time, includes:

[0020] Obtain the power supply side delay of the high-voltage circuit breaker;

[0021] Obtain the bus voltage of the power system when the high-voltage circuit breaker interrupts the near-zone fault;

[0022] The recovery voltage rise rate on the power supply side of the high-voltage circuit breaker is obtained when the near-zone fault is interrupted;

[0023] The first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the line-side oscillation voltage disappears is calculated based on the bus voltage, the recovery voltage rise rate, the overall recovery voltage rise time, the power supply side delay, and the first peak-to-peak voltage.

[0024] Optionally, the step of calculating the initial recovery voltage rise rate of the high-voltage circuit breaker using the overall recovery voltage rise time and the first peak voltage includes:

[0025] The initial recovery voltage rise rate of the high-voltage circuit breaker is obtained by calculating the difference between the first peak voltage and the overall recovery voltage rise time.

[0026] This invention also provides a high-voltage circuit breaker breaking risk analysis device, applied to power systems; the device includes:

[0027] The zero-crossing current change rate acquisition module is used to acquire the zero-crossing current change rate of the high-voltage circuit breaker when a near-zone fault occurs under the action of the current harmonic component.

[0028] The overall recovery voltage rise time calculation module is used to calculate the overall recovery voltage rise time of the high-voltage circuit breaker based on the zero-crossing current change rate.

[0029] The first peak voltage calculation module is used to calculate the first peak voltage reached by the transient recovery voltage at both ends of the high-voltage circuit breaker before the line-side oscillation voltage disappears, based on the overall recovery voltage rise time.

[0030] An initial recovery voltage rise rate calculation module is used to calculate the initial recovery voltage rise rate of the high-voltage circuit breaker using the overall recovery voltage rise time and the first peak voltage.

[0031] The judgment module is used to determine whether the initial recovery voltage rise rate is greater than a preset threshold. If so, it is determined that the high-voltage circuit breaker has a risk of failure to interrupt.

[0032] Optionally, the overall recovery voltage rise time calculation module includes:

[0033] The first peak-to-peak voltage calculation submodule is used to calculate the first peak-to-peak voltage of the oscillation voltage on the line side of the high-voltage circuit breaker.

[0034] The line surge impedance acquisition submodule is used to acquire the line surge impedance of the power system.

[0035] The rise time calculation submodule is used to calculate the rise time to the first peak voltage based on the zero-crossing current change rate, the first peak voltage and the line impedance.

[0036] The line-side delay acquisition submodule is used to acquire the line-side delay of the high-voltage circuit breaker;

[0037] The overall recovery voltage rise time calculation submodule is used to calculate the overall recovery voltage rise time of the high-voltage circuit breaker using the line-side delay and the rise time.

[0038] Optionally, the first peak-to-peak voltage calculation submodule includes:

[0039] A near-zone fault breaking current, rated short-circuit breaking current and rated voltage acquisition unit of circuit breaker is used to acquire the near-zone fault breaking current, rated short-circuit breaking current and rated voltage of the circuit breaker.

[0040] The first peak-to-peak voltage calculation unit is used to calculate the first peak-to-peak voltage of the line-side oscillation voltage of the high-voltage circuit breaker using the near-zone fault breaking current, the rated short-circuit breaking current, and the rated voltage of the circuit breaker.

[0041] The present invention also provides an electronic device, the device comprising a processor and a memory:

[0042] The memory is used to store program code and transmit the program code to the processor;

[0043] The processor is used to execute the high-voltage circuit breaker interruption risk analysis method as described above, according to the instructions in the program code.

[0044] The present invention also provides a computer-readable storage medium for storing program code for executing the high-voltage circuit breaker interruption risk analysis method as described in any of the preceding claims.

[0045] As can be seen from the above technical solutions, the present invention has the following advantages: The present invention discloses a method for analyzing the breaking risk of a high-voltage circuit breaker, specifically disclosing: obtaining the zero-crossing current change rate of the high-voltage circuit breaker under the current harmonic component when a near-zone fault occurs; calculating the overall recovery voltage rise time of the high-voltage circuit breaker based on the zero-crossing current change rate; calculating the first peak voltage reached by the transient recovery voltage at both ends of the high-voltage circuit breaker before the disappearance of the line-side oscillation voltage based on the overall recovery voltage rise time; calculating the initial recovery voltage rise rate of the high-voltage circuit breaker using the overall recovery voltage rise time and the first peak voltage; determining whether the initial recovery voltage rise rate is greater than a preset threshold, and if so, determining that the high-voltage circuit breaker has a risk of breaking failure. The present invention obtains the zero-crossing current change rate of the high-voltage circuit breaker under different harmonic components to calculate the initial recovery voltage rise rate of the high-voltage circuit breaker when a near-zone fault occurs under different harmonic components, thereby determining whether the high-voltage circuit breaker has a risk of breaking failure when a near-zone fault actually occurs in the power system, and thus adjusting parameters such as harmonic components of the power system to avoid the risk of near-zone faults. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 A flowchart illustrating the steps of a high-voltage circuit breaker interruption risk analysis method provided in this embodiment of the invention;

[0048] Figure 2 For power supply side with ITRV (Initial Transient Recovery Voltage), and line side with time delay near-zone fault delay, simplify single-phase circuit;

[0049] Figure 3 This is a schematic diagram of the initial recovery voltage rise rate as a function of harmonic content.

[0050] Figure 4 This is a schematic diagram of the initial rise time as a function of harmonic content;

[0051] Figure 5 A circuit and arc simulation model for the near-zone breaking process of a circuit breaker;

[0052] Figure 6 A schematic diagram of the near-field fault short-circuit current curve under the superposition of different harmonic contents;

[0053] Figure 7 A schematic diagram of the recovery voltage waveform under the superposition of different harmonic contents;

[0054] Figure 8 This is a structural block diagram of a high-voltage circuit breaker interruption risk analysis device provided in an embodiment of the present invention. Detailed Implementation

[0055] This invention provides a method, apparatus, equipment, and medium for analyzing the breaking risk of high-voltage circuit breakers, which is used to assess the breaking failure risk of high-voltage circuit breakers and reduce the probability of breaking failure of high-voltage circuit breakers.

[0056] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0057] Please see Figure 1 , Figure 1 A flowchart illustrating the steps of a high-voltage circuit breaker interruption risk analysis method provided in this embodiment of the invention.

[0058] This invention provides a method for analyzing the breaking risk of high-voltage circuit breakers, applicable to power systems, and specifically includes the following steps:

[0059] Step 101: Obtain the rate of change of zero-crossing current of the high-voltage circuit breaker when a near-zone fault occurs under the influence of the current harmonic component.

[0060] Step 102: Calculate the overall recovery voltage rise time of the high-voltage circuit breaker based on the zero-crossing current change rate;

[0061] When a near-field fault occurs, the superposition of different harmonic components leads to different rates of change of the zero-crossing current. In this embodiment of the invention, the rate of change of the zero-crossing current when a near-field fault occurs can be obtained based on the harmonic components and short-circuit current of the current power system. The overall recovery voltage rise time of the high-voltage circuit breaker can be calculated using the rate of change of the zero-crossing current.

[0062] In one example, step 102 may include the following sub-steps:

[0063] S21, obtain the near-zone fault breaking current, the rated short-circuit breaking current and the rated voltage of the circuit breaker;

[0064] S22, calculate the first peak-to-peak voltage of the oscillation voltage on the line side of the high-voltage circuit breaker using the near-zone fault breaking current, the rated short-circuit breaking current and the rated voltage of the circuit breaker;

[0065] S23, obtain the line surge impedance of the power system;

[0066] S24, calculate the rise time to the first peak voltage based on the zero-crossing current change rate, the first peak voltage and the line impedance;

[0067] S25, obtain the line-side time delay of the high-voltage circuit breaker;

[0068] S26, calculate the overall recovery voltage rise time of the high-voltage circuit breaker using line-side delay and rise time.

[0069] In practice, under near-zone fault conditions, the transient recovery voltage of the circuit breaker is composed of the power supply side and the line side.

[0070] Taking near-zone faults as the calculation condition: In a neutral-grounded system, with a single-phase ground fault and an initial polarity factor of 1, the corresponding power supply side has an ITRV (Initial Transient Recovery Voltage), and the line side has a time-delayed near-zone fault time delay. (Simplified single-phase circuit example follows...) Figure 2 As shown. Assume the circuit breaker's rated voltage is 550kV, and its rated short-circuit currents are 50kA and 63kA. The near-zone fault condition is L90, with a 0.5μs delay on the line side and a 2μs delay on the power supply side, and includes ITRV (Initial Transient Recovery Voltage). Perform transient characteristic calculation and analysis of the recovery voltage under harmonic effects. The simplified single-phase circuit is as follows: Figure 1 As shown. When the fault point is grounded, the current will flow through the reactance X. S X L X B A series circuit consisting of U. G X is the power supply voltage relative to ground. S X B X L These represent the power frequency reactance values ​​on the power supply side, busbar side, and line side, respectively.S Z L Z i These are the power supply side, line side TRV control element, and ITRV control element, respectively. d C dL For the power supply side and line side time delay capacitors, C B Z is the circuit breaker, Z is the line surge impedance, and L is the line length to the fault point.

[0071] When a near-field fault occurs, the first peak-to-peak voltage u of the line-side oscillation voltage L* It can be calculated using the following formula:

[0072]

[0073] in, Peak coefficient, The rated voltage of the circuit breaker. For near-field fault interruption current, This is the rated short-circuit breaking current.

[0074] The rise time of the first peak-to-peak voltage reaching the line-side voltage With line impedance and the rate of change of zero-crossing current Relatedly, with the superposition of harmonic components in the near-field fault current, the current rise rate at the zero-crossing moment increases significantly, thereby reducing the rise time of the line side to reach the first peak voltage and the overall recovery voltage rise time. :

[0075]

[0076]

[0077] in, The line-side time delay is taken as 0.5μs. GB / T 1984-2014 stipulates that when the rated voltage is higher than 252kV, the line surge impedance is 450Ω and the peak factor k is 1.6.

[0078] Step 103: Calculate the first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the line-side oscillation voltage disappears, based on the overall recovery voltage rise time.

[0079] In this embodiment of the invention, the first peak voltage reached by the transient recovery voltage across the circuit breaker before the disappearance of the line-side oscillation voltage is mainly determined by the line side; after obtaining the overall recovery voltage rise time on the line side, the first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the disappearance of the line-side oscillation voltage can be calculated based on the overall recovery voltage rise time.

[0080] In one example, step 103 may include the following sub-steps:

[0081] S31, obtain the power supply side delay of the high-voltage circuit breaker;

[0082] S32, obtain the bus voltage of the power system when the high-voltage circuit breaker interrupts a near-zone fault;

[0083] S33, obtain the recovery voltage rise rate on the power supply side of the high-voltage circuit breaker when interrupting a near-zone fault;

[0084] S34, calculates the first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the line-side oscillation voltage disappears, based on the bus voltage, recovery voltage rise rate, overall recovery voltage rise time, power supply side delay, and the first peak-to-peak voltage.

[0085] In practical implementation, when interrupting a near-zone fault, the recovery voltage rise rate on the circuit breaker power supply side is... The voltage drop across the bus under the influence of the ITRV is 1.8 kV / μs, with an initial transient recovery voltage (ITRV) duration of 1.0 μs.

[0086]

[0087] in, The multiplier is equal to 0.116 kV / kA. The peak coefficient is 1.4.

[0088] The first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the disappearance of the line-side oscillation voltage is mainly determined by the line side. The expression for the first peak voltage is:

[0089]

[0090] in, The power supply side delay is 2μs.

[0091] Step 104: Calculate the initial recovery voltage rise rate of the high-voltage circuit breaker using the overall recovery voltage rise time and the first peak voltage;

[0092] After obtaining the overall recovery voltage rise time and the first peak voltage, the initial recovery voltage rise rate of the high-voltage circuit breaker can be derived. The specific steps are as follows:

[0093] The initial recovery voltage rise rate of the high-voltage circuit breaker is obtained by calculating the difference between the rise time of the first peak voltage and the overall recovery voltage.

[0094] The formula is:

[0095]

[0096] Step 105: Determine whether the initial recovery voltage rise rate is greater than a preset threshold. If so, determine that the high-voltage circuit breaker has a risk of failure to interrupt.

[0097] In this embodiment of the invention, after calculating the initial recovery voltage rise rate when a high-voltage circuit breaker experiences a near-zone fault under different harmonic components, it can be determined whether there is a risk of circuit breaker failure.

[0098] In real-world scenarios, the higher the initial recovery voltage rise rate, the greater the risk. Therefore, a preset threshold can be used to determine whether a high-voltage circuit breaker has a significant risk of failure to interrupt a near-zone fault under the current power system parameters. If it is determined that a significant risk of failure to interrupt a near-zone fault may occur in the current power system, then various power system parameters (such as harmonic content) can be adjusted.

[0099] As shown in Table 1, for two operating conditions with short-circuit currents of 45kA and 56.7kA on the L90 line, the RRRV (initial recovery rate of rise) and initial rise time were calculated and analyzed with the superposition of the 3rd, 5th, and 7th harmonics. Table 1 lists the parameter calculation results for some operating conditions. It can be found that with the increase of rated short-circuit current, harmonic content, and harmonic frequency, the rate of change of current at the zero-crossing moment increases significantly, thereby increasing the voltage rise rate on the line side. Under the condition that the first peak voltage on the line side is constant, the time t to reach the first peak voltage is... T As the voltage decreases, the rise in voltage on the power supply side decreases relatively, and the first peak value of the recovery voltage across the circuit breaker... T While the corresponding decrease is observed, the final recovery voltage rise rate (RRRV) shows a significant increasing trend, making it more difficult for high-voltage circuit breakers to interrupt operations. Simultaneously, increasing the current rating also raises the power supply side ITRV, further increasing the recovery voltage rise rate.

[0100] Table 1

[0101]

[0102] Figure 3 This is a schematic diagram of the initial recovery voltage rise rate as a function of harmonic content. Figure 4 This is a schematic diagram showing the initial rise time as a function of harmonic content. According to... Figure 3 and Figure 4 The RRRV shows an approximately direct proportional relationship with harmonic content, while the rise time shows an approximately inverse proportional relationship. The higher the rated short-circuit current, the larger the initial value of RRRV, and the greater the slope of its increase with harmonic content. This is mainly due to the large current change rate at zero crossing. Under the condition of the same superimposed harmonic current content, the higher the harmonic frequency, the greater the increase in the current change rate, thus leading to an increase in RRRV. TThe decrease in RRRV and the decrease in tT both increase the difficulty of post-arc dielectric recovery, which is detrimental to the successful interruption of the circuit breaker.

[0103] This invention obtains the change rate of the zero-crossing current of the high-voltage circuit breaker under different harmonic components for near-zone faults, and calculates the initial recovery voltage rise rate of the high-voltage circuit breaker when a near-zone fault occurs under different harmonic components. This allows the invention to determine whether there is a risk of the high-voltage circuit breaker failing to interrupt the fault when a near-zone fault actually occurs in the power system, thereby adjusting parameters such as the harmonic components of the power system to avoid the risks when a near-zone fault occurs.

[0104] Furthermore, in this embodiment of the invention, to further study the influence of harmonic content on the later rise process of the recovery voltage of the circuit breaker near-zone fault, a circuit and arc simulation model of the circuit breaker near-zone breaking process were built in the MATLAB / Simulink module according to the simplified circuit of the circuit breaker near-zone fault test, such as... Figure 5 As shown. I h This serves as a harmonic current source, introducing harmonic content into the short-circuit current. Corresponding resistors are added to the power frequency reactances on both the power supply and line sides to simulate the line resistance present in real-world testing. The bus reactance value X... B It is relatively small and was not considered during modeling.

[0105] The Mayr arc model in the simulation model is used to describe the arc behavior during the circuit breaker's opening process. It is built using a differential equation editor, step signals, setpoint detection, and a controlled current source. Its principle equation is:

[0106]

[0107] Where g is the arc conductance. Arc voltage It is the arc current. Where is the arc time constant and P is the arc heat dissipation power. The Mayr arc model obtains the arc characteristic curve by studying the relationship between arc current and arc voltage. It is applicable to arc processes with small currents and in the zero-region stage, and is therefore used to calculate the post-arc recovery voltage rise process.

[0108] The influence of harmonics on the transient characteristics within microseconds before the recovery voltage was obtained through initial RRRV calculations. To further investigate the influence of harmonic content on the transient characteristics of near-field fault recovery voltage, a simulation study was conducted in the MATLAB / Simulink module with a rated short-circuit current of 50kA and superimposed with five harmonic currents of different contents. The influence of harmonic content on the peak value and rise time of the post-arc recovery voltage was quantitatively analyzed.

[0109] The injection of 5th harmonic currents with varying concentrations is primarily achieved by adjusting the peak current and frequency in the harmonic current source Ih. The total near-zone fault short-circuit current is as follows: Figure 6 As shown. Figure 7 The recovery voltage waveforms under different harmonic content superposition are given. It can be seen that the evolution law of the recovery voltage waveform under the action of harmonics is basically the same. The recovery voltage rise rate begins to increase with the increase of harmonic content around 50μs. The recovery voltage under the action of harmonics begins to be higher than the fundamental wave recovery voltage. Finally, the recovery voltage under the action of harmonics reaches the peak value earlier, and the peak value is significantly higher than the fundamental wave recovery voltage.

[0110] Please see Figure 8 , Figure 8 This is a structural block diagram of a high-voltage circuit breaker interruption risk analysis device provided in an embodiment of the present invention.

[0111] This invention provides a high-voltage circuit breaker breaking risk analysis device for use in power systems; the device includes:

[0112] The zero-crossing current change rate acquisition module 801 is used to acquire the zero-crossing current change rate of the high-voltage circuit breaker when a near-zone fault occurs under the action of the current harmonic component.

[0113] The overall recovery voltage rise time calculation module 802 is used to calculate the overall recovery voltage rise time of the high-voltage circuit breaker based on the zero-crossing current change rate.

[0114] The first peak voltage calculation module 803 is used to calculate the first peak voltage reached by the transient recovery voltage at both ends of the high voltage circuit breaker before the line-side oscillation voltage disappears, based on the overall recovery voltage rise time.

[0115] The initial recovery voltage rise rate calculation module 804 is used to calculate the initial recovery voltage rise rate of the high-voltage circuit breaker using the overall recovery voltage rise time and the first peak voltage.

[0116] The judgment module 805 is used to determine whether the initial recovery voltage rise rate is greater than a preset threshold. If so, it is determined that the high-voltage circuit breaker has a risk of failure to open.

[0117] In this embodiment of the invention, the overall recovery voltage rise time calculation module 802 includes:

[0118] The first peak-to-peak voltage calculation submodule is used to calculate the first peak-to-peak voltage of the oscillation voltage on the line side of the high-voltage circuit breaker.

[0119] The line surge impedance acquisition submodule is used to acquire the line surge impedance of the power system.

[0120] The rise time calculation submodule is used to calculate the rise time to the first peak voltage based on the zero-crossing current change rate, the first peak voltage, and the line impedance.

[0121] The line-side delay acquisition submodule is used to acquire the line-side delay of the high-voltage circuit breaker;

[0122] The overall recovery voltage rise time calculation submodule is used to calculate the overall recovery voltage rise time of the high-voltage circuit breaker using line-side delay and rise time.

[0123] In this embodiment of the invention, the first peak-to-peak voltage calculation submodule includes:

[0124] The near-zone fault breaking current, rated short-circuit breaking current and rated voltage of the circuit breaker are obtained by acquiring the near-zone fault breaking current, rated short-circuit breaking current and rated voltage of the circuit breaker.

[0125] The first peak-to-peak voltage calculation unit is used to calculate the first peak-to-peak voltage of the line-side oscillation voltage of the high-voltage circuit breaker using the near-zone fault breaking current, the rated short-circuit breaking current, and the rated voltage of the circuit breaker.

[0126] In this embodiment of the invention, the first peak voltage calculation module 803 includes:

[0127] The power supply side delay acquisition submodule is used to acquire the power supply side delay of the high-voltage circuit breaker;

[0128] The bus voltage acquisition submodule is used to acquire the bus voltage of the power system when the high-voltage circuit breaker interrupts a near-zone fault.

[0129] The recovery voltage rise rate acquisition submodule is used to acquire the recovery voltage rise rate on the power supply side of the high-voltage circuit breaker when a near-zone fault is interrupted.

[0130] The first peak voltage calculation submodule is used to calculate the first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the line-side oscillation voltage disappears, based on the bus voltage, recovery voltage rise rate, overall recovery voltage rise time, power supply side delay, and the first peak-to-peak voltage.

[0131] In this embodiment of the invention, the initial recovery voltage rise rate calculation module includes:

[0132] The initial recovery voltage rise rate calculation submodule is used to calculate the difference between the first peak voltage and the overall recovery voltage rise time to obtain the initial recovery voltage rise rate of the high-voltage circuit breaker.

[0133] This invention also provides an electronic device, which includes a processor and a memory:

[0134] The memory is used to store program code and transfer the program code to the processor;

[0135] The processor is used to execute the high-voltage circuit breaker breaking risk analysis method of this invention according to the instructions in the program code.

[0136] This invention also provides a computer-readable storage medium for storing program code for executing the high-voltage circuit breaker interruption risk analysis method of this invention.

[0137] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0138] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0139] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, apparatus, or computer program products. Therefore, embodiments of the present invention can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of the present invention can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0140] Embodiments of the present invention are described with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations 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, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0141] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0142] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0143] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0144] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0145] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for analyzing the breaking risk of a high-voltage circuit breaker, characterized in that, Applied to power systems; the method includes: Obtain the rate of change of zero-crossing current of the high-voltage circuit breaker when a near-zone fault occurs under the influence of the current harmonic component; The overall recovery voltage rise time of the high-voltage circuit breaker is calculated based on the zero-crossing current change rate. The first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the line-side oscillation voltage disappears is calculated based on the overall recovery voltage rise time. The initial recovery voltage rise rate of the high-voltage circuit breaker is calculated using the overall recovery voltage rise time and the first peak voltage. Determine whether the initial recovery voltage rise rate is greater than a preset threshold. If so, determine that the high-voltage circuit breaker has a risk of failure to interrupt.

2. The method according to claim 1, characterized in that, The step of calculating the overall recovery voltage rise time of the high-voltage circuit breaker based on the zero-crossing current change rate includes: Calculate the peak-to-peak voltage of the first peak of the oscillation voltage on the line side of the high-voltage circuit breaker; Obtain the line surge impedance of the power system; The rise time to the first peak voltage is calculated based on the zero-crossing current change rate, the first peak voltage, and the line impedance. Obtain the line-side time delay of the high-voltage circuit breaker; The overall recovery voltage rise time of the circuit breaker is calculated using the line-side delay and the rise time.

3. The method according to claim 2, characterized in that, The step of calculating the first peak-to-peak voltage of the oscillation voltage on the line side of the high-voltage circuit breaker includes: Obtain the near-zone fault breaking current, the rated short-circuit breaking current, and the rated voltage of the circuit breaker; The first peak-to-peak voltage of the line-side oscillation voltage of the high-voltage circuit breaker is calculated using the near-zone fault breaking current, the rated short-circuit breaking current, and the rated voltage of the circuit breaker.

4. The method according to claim 2, characterized in that, The step of calculating the first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the disappearance of the line-side oscillation voltage, based on the overall recovery voltage rise time, includes: Obtain the power supply side delay of the high-voltage circuit breaker; Obtain the bus voltage of the power system when the high-voltage circuit breaker interrupts the near-zone fault; The recovery voltage rise rate on the power supply side of the high-voltage circuit breaker is obtained when the near-zone fault is interrupted; The first peak voltage reached by the transient recovery voltage across the high-voltage circuit breaker before the line-side oscillation voltage disappears is calculated based on the bus voltage, the recovery voltage rise rate, the overall recovery voltage rise time, the power supply side delay, and the first peak-to-peak voltage.

5. The method according to claim 1, characterized in that, The step of calculating the initial recovery voltage rise rate of the high-voltage circuit breaker using the overall recovery voltage rise time and the first peak voltage includes: The initial recovery voltage rise rate of the high-voltage circuit breaker is obtained by calculating the quotient between the first peak voltage and the overall recovery voltage rise time.

6. A high-voltage circuit breaker interruption risk analysis device, characterized in that, Applied to power systems; the device includes: The zero-crossing current change rate acquisition module is used to acquire the zero-crossing current change rate of the high-voltage circuit breaker when a near-zone fault occurs under the action of the current harmonic component. The overall recovery voltage rise time calculation module is used to calculate the overall recovery voltage rise time of the high-voltage circuit breaker based on the zero-crossing current change rate. The first peak voltage calculation module is used to calculate the first peak voltage reached by the transient recovery voltage at both ends of the high-voltage circuit breaker before the line-side oscillation voltage disappears, based on the overall recovery voltage rise time. An initial recovery voltage rise rate calculation module is used to calculate the initial recovery voltage rise rate of the high-voltage circuit breaker using the overall recovery voltage rise time and the first peak voltage. The judgment module is used to determine whether the initial recovery voltage rise rate is greater than a preset threshold. If so, it is determined that the high-voltage circuit breaker has a risk of failure to interrupt.

7. The apparatus according to claim 6, characterized in that, The overall recovery voltage rise time calculation module includes: The first peak-to-peak voltage calculation submodule is used to calculate the first peak-to-peak voltage of the oscillation voltage on the line side of the high-voltage circuit breaker. The line surge impedance acquisition submodule is used to acquire the line surge impedance of the power system. The rise time calculation submodule is used to calculate the rise time to the first peak voltage based on the zero-crossing current change rate, the first peak voltage and the line impedance. The line-side delay acquisition submodule is used to acquire the line-side delay of the high-voltage circuit breaker; The overall recovery voltage rise time calculation submodule is used to calculate the overall recovery voltage rise time of the high-voltage circuit breaker using the line-side delay and the rise time.

8. The apparatus according to claim 7, characterized in that, The first peak-to-peak voltage calculation submodule includes: A near-zone fault breaking current, rated short-circuit breaking current and rated voltage acquisition unit of circuit breaker is used to acquire the near-zone fault breaking current, rated short-circuit breaking current and rated voltage of the circuit breaker. The first peak-to-peak voltage calculation unit is used to calculate the first peak-to-peak voltage of the line-side oscillation voltage of the high-voltage circuit breaker using the near-zone fault breaking current, the rated short-circuit breaking current, and the rated voltage of the circuit breaker.

9. An electronic device, characterized in that, The device includes a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the high-voltage circuit breaker interruption risk analysis method according to any one of the claims 1-5 according to the instructions in the program code.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store program code for executing the high-voltage circuit breaker interruption risk analysis method according to any one of claims 1-5.

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