High-voltage circuit breaker RDDS parameter voltage reduction measurement method, terminal and storage medium

Abstract

The invention discloses a high-voltage circuit breaker RDDS parameter voltage reduction measurement method, a terminal and a storage medium, and the method comprises the steps: obtaining a rated voltage Ue of a circuit breaker, taking kUe as a test voltage (k is smaller than 1), and carrying out the phase selection and closing operation of the circuit breaker under the test voltage by taking a voltage zero crossing point as a target closing phase; recording the phase selection closing operation in the closing target time interval at the closing moment of the circuit breaker as effective operation, and recording the phase selection closing operation in the closing target time interval at both the closing moment of the circuit breaker and the current abrupt change moment of the branch where the circuit breaker is located as successful operation; the lower limit values of different RDDSs and the probability that the RDDS of the circuit breaker is larger than the lower limit values are calculated, and a distribution curve of the RDDSs is obtained through fitting; and determining a lower limit value from the distribution curve of the RDDS based on the probability index that the phase-controlled closing device controls the successful phase selection closing of the circuit breaker, so as to set the fixed value of the phase-controlled closing device. The test of the circuit breaker with the RRDS smaller than 1 is realized by reducing the test voltage, and the voltage zero-crossing closing is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of phase-controlled opening and closing (CS) of circuit breakers, and in particular to a method and system for measuring a voltage drop of a parameter of a rate of decrease of dielectric strength (RDDS) of a high-voltage circuit breaker. Background Art

[0002] When the load has energy storage characteristics, such as capacitive load or inductive load, a transition process will occur when closing the AC three-phase circuit, accompanied by inrush current, arc reignition, overvoltage and other phenomena. In high-voltage and high-capacity scenarios, the transition process will cause unacceptable hazards, such as false tripping of relay protection, severe ablation of circuit breaker contacts, external insulation breakdown caused by overvoltage, and UHV DC lockout. In order to solve the voltage or current impact caused by random closing, the phase-controlled closing technology realizes the zero-crossing closing of capacitive load voltage, the peak closing of inductive load voltage, and the controlled closing of any voltage phase according to the residual magnetism level of the transformer. In order to achieve precise control of the closing phase, the influence of the pre-breakdown of the main contact of the circuit breaker needs to be considered. During the closing process of the main contact, its insulation strength will gradually decrease. When the main contact is close to the closed state, the voltage between the contacts may cause insulation breakdown, and the circuit will be turned on in advance, so that the actual closing time is ahead of the mechanical closing time of the main contact. Uncontrolled pre-breakdown will affect the effect of phase-controlled closing on the suppression of the transition process. The RDDS parameter of the main contact of the circuit breaker is an important parameter that needs to be used in phase-controlled closing. Taking the classic linear RDDS theory as an example, when the RDDS per unit value is greater than 1, even if pre-breakdown occurs, controlled closing at any angle can be achieved. When RDDS is less than 1, the capacitive load avoids uncontrollable pre-breakdown by delay; when RDDS continues to decrease, the inductive load closes the rising section of the break voltage by advance. RDDS greater than 1 means that the mechanical speed is greater than the relevant electrical speed, and the circuit breaker is fast and sensitive enough to meet the requirements of phase-controlled closing. At high voltage levels, due to the increase in voltage, the electrical speed of the break increases proportionally, but due to the increase in the closing power of the circuit breaker, the mechanical speed cannot be increased synchronously, resulting in the RDDS of high-voltage circuit breakers, especially those with a voltage level of 500kV and above, which is generally less than 1 and does not meet the technical requirements for closing at any angle. The RDDS parameter of the break reflects the characteristics of insulation breakdown and is a set of experimentally obtained data. Like most high-voltage experiments, the test result data under the same conditions has the characteristics of normal distribution. Since the electric field at the circuit breaker break is not an extremely non-uniform field, the RDDS parameters are almost unaffected by the polarity of the applied voltage. When using the RDDS parameters, it is necessary to determine the minimum possibility according to a certain distribution probability, so as to give the optimal closing control interval of the controllable pre-breakdown through methods such as the tangent method.

[0003] In the prior art, the pre-breakdown time prediction method based on the self-learning of the circuit breaker RDDS parameters performs self-correction of the RDDS parameters. Based on the test data under the rated voltage, the RDDS data is obtained by the intercept method and weighted averaged. However, the closing angle of this method is dispersed, and the parameters such as the main contact opening distance and voltage during pre-breakdown are different. The experimental data cannot reflect the probability distribution characteristics of the RDDS parameters. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the present invention provides a voltage reduction measurement method, terminal and storage medium for RDDS parameters of high-voltage circuit breakers. The test of circuit breakers with RRDS less than 1 is achieved by reducing the test voltage, thereby ensuring the technical requirements of the voltage zero-crossing closing test. The lower limit value of RDDS and its distribution probability are obtained by the slope method, which fully meets the requirements of the phase-controlled closing device for closing parameter setting and closing success probability.

[0005] The present invention adopts the following technical solution.

[0006] The present invention proposes a method for measuring the voltage drop of RDDS parameters of a high-voltage circuit breaker, comprising:

[0007] Obtain the grid electrical parameters used for transient calculation, based on the grid transient simulation model, in accordance with the requirements of transient process suppression index, with the minimum grid transient impact as the optimization goal, and determine the closing target time interval of the circuit breaker phase selection closing operation according to the voltage zero crossing time;

[0008] Get the circuit breaker rated voltage U e , in kU e is the test voltage, k<1, and the circuit breaker phase selection closing operation is performed under the test voltage with the voltage zero crossing point as the target closing phase; when the circuit breaker closing moment is within the closing target time interval, the phase selection closing operation is recorded as a valid operation; when the circuit breaker closing moment and the moment of the current mutation of the branch where the circuit breaker is located are both within the closing target time interval, the phase selection closing operation is recorded as a successful operation;

[0009] Different lower limits of RDDS are calculated using each test voltage and test power supply angular frequency, and the proportion of successful operation times in the effective operation times under each test voltage is used as the probability that the RDDS of the circuit breaker is greater than the lower limit. According to different lower limits of RDDS and the probability that the RDDS of the circuit breaker is greater than the lower limit, the distribution curve of RDDS is fitted.

[0010] Based on the probability index of the phase-controlled closing device controlling the circuit breaker to close the phase successfully, the lower limit of RDDS is determined from the distribution curve of RDDS, which is used as the voltage reduction measurement result of RDDS parameter of high-voltage circuit breaker to adjust the fixed value of the phase-controlled closing device.

[0011] Preferably, the electrical parameters of the power grid used for transient calculation include: power supply capacity, power supply impedance, load impedance, and actual closing phase of the circuit breaker.

[0012] Preferably, the closing target time interval of the circuit breaker phase selection closing operation determined according to the voltage zero-crossing time is expressed as [t0-τ, t0+τ], wherein t0 is the voltage zero-crossing time.

[0013] Preferably, when executing the phase-selective closing operation of the circuit breaker, the mechanical closing moment of the main contacts of the circuit breaker is determined by the auxiliary break of the circuit breaker as the closing moment of the circuit breaker.

[0014] Preferably, the test voltage is kU e When the voltage zero point is used as the target closing phase, M phase-selective closing operations of the circuit breaker are performed, among which the phase-selective closing operations whose closing moment of the circuit breaker is within the closing target time interval are recorded as valid operations, and the number of valid operations is N. The phase-selective closing operations whose mechanical closing moment of the main contacts of the circuit breaker and the moment of the current mutation of the branch where the circuit breaker is located are both within the closing target time interval are recorded as successful operations, and the number of successful operations is n.

[0015] Preferably, the rate of change of the test voltage at the voltage zero crossing point is used as a reference value for calculating RDDS.

[0016] Preferably, the lower limit value of RDDS is calculated using the following relationship:

[0017]

[0018] In the formula, k RDDS is the lower limit of RDDS, kU e is the effective value of the test voltage, U e is the effective value of the circuit breaker rated voltage, and ω is the test power angular frequency.

[0019] Preferably, the probability that the RDDS of the circuit breaker is greater than the lower limit is calculated using the following relationship:

[0020]

[0021] Where p is the probability that the RDDS of the circuit breaker is greater than the lower limit, n is the cumulative sum of the number of successful operations under each test voltage, and N is the cumulative sum of the number of effective operations under each test voltage.

[0022] A terminal comprises a processor and a storage medium; the storage medium is used to store instructions; the processor is used to operate according to the instructions to execute the steps of the method.

[0023] A computer-readable storage medium stores a computer program, which implements the steps of the method when executed by a processor.

[0024] The beneficial effects of the present invention are that, compared with the prior art, at least the present invention proposes a method for measuring the voltage drop of the RDDS parameter of a high-voltage circuit breaker, and adopts a statistical method of high-voltage test to obtain the distribution law of the electric field breakdown characteristics, which can not only obtain the lower limit value of the RDDS, but also obtain the corresponding distribution probability. After a set of probability distributions are obtained through experiments under multiple voltages, the RDDS distribution curve can be fitted according to the normal distribution probability, so that the phase-controlled closing device can determine the RDDS engineering constant according to the success probability requirement.

[0025] This method is based on repeated test results under the same working conditions. It is not only meaningful for the RDDS straight line theory, but also can be used for the setting of the phase-controlled closing device when the RDDS is not a straight line, thus solving the dispersion problem of the RDDS. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flow chart of the voltage reduction measurement method of the RDDS parameter of the high-voltage circuit breaker proposed by the present invention;

[0027] Figure 2 It is a schematic diagram of reducing the test voltage and increasing the RDDS per unit value proposed by the present invention;

[0028] Figure 3 is a schematic diagram of a method for identifying a valid operation and a successful operation in an embodiment of the present invention;

[0029] Figure 4 It is a RDDS distribution curve diagram in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only embodiments of a part of the present invention, rather than all embodiments. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0031] The present invention proposes a method for measuring the voltage drop of RDDS parameters of a high-voltage circuit breaker. Figure 1 As shown, including:

[0032] Step 1: Obtain the electrical parameters of the power grid for transient calculation. Based on the power grid transient simulation model, in accordance with the requirements of the transient process suppression index, with the minimum transient impact of the power grid as the optimization goal, determine the closing target time interval of the circuit breaker phase selection closing operation according to the voltage zero crossing time.

[0033] Specifically, the electrical parameters of the power grid used for transient calculation include, but are not limited to: power supply capacity, power supply impedance, load impedance, and actual closing phase of the circuit breaker.

[0034] Specifically, the closing target time interval of the circuit breaker phase selection closing operation determined according to the voltage zero-crossing time is expressed as [t0-τ, t0+τ], where t0 is the voltage zero-crossing time.

[0035] In a non-limiting preferred embodiment, when the circuit breaker closes the shunt capacitor bank with the neutral point grounded, in order to ensure that the inrush current is not greater than 2 times the rated current, the closing target time interval is [t0-0.5, t0+0.5], where t0 is the voltage zero crossing time, in ms, so as to achieve controllable circuit breaker contact erosion. This control result requires the corresponding closing target time interval to be 0.5ms around the voltage zero crossing time.

[0036] The closing target time interval is the control accuracy requirement put forward by the user for the phase-controlled closing operation of the circuit breaker from the perspective of control effect. It is also an important input data for determining the effectiveness of the phase-controlled closing operation of the circuit breaker and ensuring the accuracy of RDDS measurement.

[0037] The user requires a smaller transient impact, so the width of the closing target time interval is narrower, and the phase-controlled closing device needs to ensure that the fluctuation of the actual closing time is smaller.

[0038] Step 2: Get the circuit breaker rated voltage U e , in kU e is the test voltage, k<1, and the circuit breaker phase selection closing operation is performed under the test voltage with the voltage zero crossing point as the target closing phase; when the circuit breaker closing moment is within the closing target time interval, the phase selection closing operation is recorded as a valid operation; when the circuit breaker closing moment and the moment of the current mutation of the branch where the circuit breaker is located are both within the closing target time interval, the phase selection closing operation is recorded as a successful operation.

[0039] Phase selection and closing of circuit breaker refers to controlling the phase angle of the primary current relative to the system voltage at the starting moment when each phase circuit of the circuit breaker is turned on, so as to suppress the transient process when the load is put into operation. Due to the dispersion of the circuit breaker closing action time and RDDS, the influence of the deviation of mechanical characteristics and electrical characteristics should be considered when calculating the target closing phase. Among them, the mechanical characteristics are affected by factors such as ambient temperature, static time, control voltage, energy storage oil pressure, etc., and the electrical characteristics are affected by SF6 density and contact gap insulation withstand voltage strength. The present invention proposes to use the voltage zero crossing point as the target closing phase, which not only corresponds to the closing target time interval, but also can improve the calculation accuracy of the RDDS per unit value.

[0040] Specifically, when executing the phase selection closing operation of the circuit breaker, the mechanical closing moment of the main contact of the circuit breaker is determined through the auxiliary break of the circuit breaker as the closing moment of the circuit breaker.

[0041] In order to measure the RDDS value, it is also necessary to know the mechanical closing time of the circuit breaker. The mechanical operation time of the circuit breaker is dispersed, that is, the delay from issuing the closing command to closing the main contact is unstable. The mechanical closing time of the main contact can be determined through the auxiliary break of the circuit breaker. Compared with the method of using auxiliary contacts, the auxiliary break has a strict synchronization relationship with the main break, which can improve the accuracy of the experimental results.

[0042] The circuit closing moment is determined by the current mutation. When the circuit where the main contact is located is connected, the current in the loop is not zero and mutates. The accurate collection of the circuit closing moment can be achieved through the current zero-crossing comparison.

[0043] Specifically, when the test voltage is kU e When the voltage zero point is used as the target closing phase, M phase-selective closing operations of the circuit breaker are performed, among which the phase-selective closing operations whose closing moment of the circuit breaker is within the closing target time interval are recorded as valid operations, and the number of valid operations is N. The phase-selective closing operations whose mechanical closing moment of the main contacts of the circuit breaker and the moment of the current mutation of the branch where the circuit breaker is located are both within the closing target time interval are recorded as successful operations, and the number of successful operations is n.

[0044] Specifically, in the embodiment, the value of k is 0.1, 0.3, 0.5, and 0.7. The test voltage is from 0.1U e At the beginning, when the effective operation times of the circuit breaker phase selection closing operation reach the set times, the test voltage is increased to 0.3U e Perform the circuit breaker phase selection and closing operation again, and so on, until the test voltage reaches 0.7U e The number of effective operation times of the phase selection and closing operation of the lower circuit breaker reaches the set number, and the phase selection and closing operation of the circuit breaker is ended.

[0045] The mechanical closing moment of the main contacts of the circuit breaker is within the closing target time interval, which is a characterization of the correctness of the closing operation of the circuit breaker under consideration of the mechanical operation delay of the circuit breaker. Therefore, the present invention proposes that the mechanical closing moment of the main contacts of the circuit breaker is within the closing target time interval as a criterion for whether the phase selection closing operation is effective; the present invention proposes that the phase selection closing operation in which the mechanical closing moment of the main contacts of the circuit breaker and the moment of the current mutation of the branch where the circuit breaker is located are both within the closing target time interval is a successful operation, and the moment of the current mutation and real-time performance of the branch where the circuit breaker is located are within the closing target time interval, is a characterization of the reliable closing operation of the circuit breaker, and these two moments are easy to obtain. The two moments are combined as a criterion for whether the phase selection closing operation is successful, which is not only reliable but also easy to operate.

[0046] In addition, when the test voltage is reduced to kU e The mechanical closing moment of the main contact can be determined through the auxiliary break of the circuit breaker, and the test voltage is reduced to kUe It also ensures that the actual closing phase of the circuit breaker phase selection closing operation is the voltage zero crossing point. Under the premise that the actual closing phase of the circuit breaker phase selection closing operation is the voltage zero crossing point, the current mutation moment of the branch where the circuit breaker is located can be obtained more accurately; therefore, the premise of the criterion for whether the phase selection closing operation proposed by the present invention is effective and successful is to reduce the test voltage.

[0047] Step 3, using each test voltage and test power angular frequency to calculate different lower limit values ​​of RDDS, and taking the proportion of successful operation times in the effective operation times under each test voltage as the probability that the RDDS of the circuit breaker is greater than the lower limit value; according to different lower limit values ​​of RDDS and the probability that the RDDS of the circuit breaker is greater than the lower limit value, the distribution curve of RDDS is fitted.

[0048] like Figure 2 As shown, the dotted line in the figure is the rated voltage U of the circuit breaker e , the solid line is the test voltage kU e . The break of a high-voltage circuit breaker generally has measures to make the electric field uniform, and the breakdown voltage is basically independent of the polarity. Therefore, the break voltage generally takes the absolute value of the actual voltage, and the solid line is the absolute value curve of the test voltage. Point M is the zero-crossing point of the sinusoidal voltage. The rate of change of the test voltage at point M is the largest in the entire sinusoidal curve. Therefore, when the circuit breaker phase selection and closing operation is performed with the voltage zero-crossing point as the target closing phase, the rate of change of the test voltage at the voltage zero-crossing point is used as the reference value for calculating RDDS. When the test voltage drops, the rate of change of the voltage at point M also drops proportionally. The oblique line in the figure indicates that RDDS is greater than 1. When the slope of the oblique line is greater than or equal to the slope of point M (that is, the voltage change rate at point M), it can be ensured that the oblique line first intersects with the voltage curve at point M during the left shift, as shown by the dotted line in the figure, to achieve voltage zero-crossing closing. On the contrary, when the slope of the oblique line is less than the slope of point M (i.e., the voltage change rate at point M), the left shift of the oblique line will first intersect with the left half-wave, and the intersection point is the pre-breakdown point, and successful voltage zero-crossing closing cannot be achieved at this time. Therefore, the present invention reduces the test voltage and uses the change rate of the test voltage at the voltage zero-crossing point as the reference value for calculating RDDS, thereby achieving RDDS greater than 1, thereby ensuring the execution reliability of the phase selection closing operation of closing the phase circuit breaker with the voltage zero-crossing point as the target under the test voltage.

[0049] Different test voltages correspond to specific RDDS reference values, that is, the slope of the test voltage at the zero point is the slope of the oblique line of RDDS = 1. When the actual RDDS is higher than the specific RDDS reference value according to the probability distribution, the effective operation can be successful because no pre-breakdown occurs; on the contrary, when the actual RDDS is lower than the specific RDDS reference value, the pre-breakdown occurs outside the effective range before the main contact is mechanically closed, and the operation fails.

[0050] The vertical coordinates in the three coordinate systems in the figure are the absolute value of the break voltage, the auxiliary break state, and the current of the circuit where the circuit breaker is located from top to bottom. In the first coordinate system, when RDDS is less than 1, before the RDDS straight line intersects with the voltage zero point B, it intersects with the voltage curve at point A. After point A, the voltage of the break is greater than the insulation strength, and a pre-breakdown will occur at time t1. At this time, the break voltage is u. The non-zero break voltage will bring about a sudden change in the current of the circuit where the circuit breaker is located. The third coordinate system shows that the current of the circuit where the circuit breaker is located will start to rise from point D, and point D is the actual closing moment of the circuit breaker.

[0051] The auxiliary break of the circuit breaker is strictly synchronized with the main break. Through the time compensation of the software, the actual closing time C of the main break can be obtained. According to the requirements for the closing effect, the width of the closing target time interval Δt centered on point B can be calculated. When point C falls into the closing target time interval Δt, the test is judged to be a valid operation, and the number of valid operations N is accumulated by 1.

[0052] When RDDS is greater than or equal to 1, since no pre-breakdown occurs, the circuit connection moment coincides with the main contact closing moment, and point D falls into the closing target time interval Δt. This effective operation is a successful operation, and the number of successful operations n is accumulated by 1.

[0053] The circuit breaker phase selection and closing operation is repeated multiple times under the experimental voltage. When the effective operation number N reaches the set number, the operation process data has a probability distribution characteristic. In the embodiment, the set number is not less than 20 times.

[0054] The lower limit of RDDS is calculated using the following relationship:

[0055]

[0056] In the formula, k RDDS is the lower limit of RDDS, kU e is the effective value of the test voltage, U e is the effective value of the circuit breaker rated voltage, and ω is the test power angular frequency.

[0057] The probability that the RDDS of the circuit breaker is greater than the lower limit is calculated using the following relationship:

[0058]

[0059] Where p is the probability that the RDDS of the circuit breaker is greater than the lower limit, n is the cumulative sum of the number of successful operations under each test voltage, and N is the cumulative sum of the number of effective operations under each test voltage.

[0060] Step 4, based on the probability index of the phase-controlled closing device controlling the circuit breaker to close the selected phase successfully, determine the lower limit value of RDDS from the distribution curve of RDDS as the voltage reduction measurement result of the RDDS parameter of the high-voltage circuit breaker to set the fixed value of the phase-controlled closing device.

[0061] The closing operation of the voltage zero crossing point of the circuit breaker is performed under different test voltages, and multiple probabilities p are obtained. The probability p corresponds to the lower limit value k of RDDS RDDS , according to the probability p and the lower limit k RDDS , the distribution curve of RDDS is obtained based on normal distribution fitting, such as Figure 4 As shown, the expected value K and variance σ of the distribution curve. In the figure, k1 represents the lower limit value of any RDDS, and the shaded part in the figure represents the area under the distribution curve on the right side of k1, which is the probability that the actual value of RDDS is greater than k1. Therefore, based on the probability index of the phase-controlled closing device controlling the circuit breaker to select the phase for closing successfully, the lower limit value of RDDS is determined from the distribution curve of RDDS, which is used as the voltage reduction measurement result of the RDDS parameter of the high-voltage circuit breaker to adjust the fixed value of the phase-controlled closing device.

[0062] RDDS is a non-common parameter of circuit breakers. The existing technology measures it according to its basic definition, that is, adjusting different main contact opening distances and then DC voltage testing. The distribution interval of RDDS of high-voltage circuit breakers used for phase-selective closing is [0.1,1]. Circuit breakers with RDDS less than 0.1 have poor performance, limited controllable closing angles, and cannot achieve acceptable transient process suppression effects, so they are not suitable for phase-controlled closing. Therefore, in the test project, RDDS less than 0.1 and its corresponding high-voltage circuit breakers are not considered. The higher the RDDS of the circuit breaker, the more conducive it is to the phase-controlled closing experiment. However, the existing technology cannot measure data for circuit breakers with high voltage levels with RDDS less than 1. When the test voltage is reduced to 0.1 times the rated voltage of the circuit breaker, since the base value of RDDS is the maximum value of the change rate of the test voltage, the RDDS obtained after the voltage reduction measurement is increased by 10 times, so that the RDDS reaches a level greater than 1. Therefore, it is possible to measure data for circuit breakers with RDDS less than 1, solving the problem that circuit breakers with voltage levels of 220kV and above cannot be measured due to low RDDS.

[0063] The above test process is performed in sequence at 0.3, 0.5, 0.7, and 0.9 times the rated voltage to obtain the RDDS lower limit value and its distribution probability. After obtaining a set of RDDS lower limit values ​​and their probability distribution, the RDDS parameter distribution relationship of the circuit breaker can be obtained by fitting the normal distribution curve. When setting the parameters of the phase-controlled closing device, the RDDS lower limit value available for the circuit breaker is calculated based on the requirements for the closing success probability. For example, when the closing success rate is required to be 95%, an RDDS value k can be obtained from the RDDS distribution curve. RDDS, the actual RDDS of the circuit breaker is greater than k RDDS The probability is 95%, k RDDS It can be used for setting fixed values ​​of tangent method or equal division method.

[0064] Based on the test results of multiple repeated closing operations under the same working conditions, the present invention not only gives the lower limit value of RDDS, but also gives the corresponding probability distribution. The test results are not only meaningful for the RDDS straight line theory, but also can be used for the setting of the phase-controlled closing device when the RDDS is not a straight line.

[0065] The present disclosure may be a system, a method and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for causing a processor to implement various aspects of the present disclosure.

[0066] A computer-readable storage medium may be a tangible device that can hold and store instructions used by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media (a non-exhaustive list) include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, such as a punch card or a raised structure in a groove on which instructions are stored, and any suitable combination of the foregoing. As used herein, a computer-readable storage medium is not to be interpreted as a transient signal per se, such as a radio wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse through a fiber optic cable), or an electrical signal transmitted through a wire.

[0067] The computer-readable program instructions described herein can be downloaded from a computer-readable storage medium to each computing / processing device, or downloaded to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network can include copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. The network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions for storage in the computer-readable storage medium in each computing / processing device.

[0068] The computer program instructions for performing the operation of the present disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages, such as Smalltalk, C++, etc., and conventional procedural programming languages, such as "C" language or similar programming languages. Computer-readable program instructions may be executed completely on a user's computer, partially on a user's computer, as an independent software package, partially on a user's computer, partially on a remote computer, or completely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., using an Internet service provider to connect via the Internet). In some embodiments, an electronic circuit, such as a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA), may be customized by utilizing the state information of the computer-readable program instructions, and the electronic circuit may execute the computer-readable program instructions, thereby realizing various aspects of the present disclosure.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for measuring the voltage drop of RDDS parameters of a high-voltage circuit breaker, characterized in that: include: Obtain the grid electrical parameters used for transient calculation, based on the grid transient simulation model, in accordance with the requirements of transient process suppression index, with the minimum grid transient impact as the optimization goal, and determine the closing target time interval of the circuit breaker phase selection closing operation according to the voltage zero crossing time; Get the circuit breaker rated voltage U e , in kU e is the test voltage, k<1, and the circuit breaker phase selection closing operation is performed under the test voltage with the voltage zero crossing point as the target closing phase; when the circuit breaker closing moment is within the closing target time interval, the phase selection closing operation is recorded as a valid operation; when the circuit breaker closing moment and the moment of the current mutation of the branch where the circuit breaker is located are both within the closing target time interval, the phase selection closing operation is recorded as a successful operation; Different lower limits of RDDS are calculated using each test voltage and test power supply angular frequency, and the proportion of successful operation times in the effective operation times under each test voltage is used as the probability that the RDDS of the circuit breaker is greater than the lower limit. According to different lower limits of RDDS and the probability that the RDDS of the circuit breaker is greater than the lower limit, the distribution curve of RDDS is fitted. Based on the probability index of the phase-controlled closing device controlling the circuit breaker to close the phase successfully, the lower limit of RDDS is determined from the distribution curve of RDDS, which is used as the voltage reduction measurement result of RDDS parameter of high-voltage circuit breaker to adjust the fixed value of the phase-controlled closing device.

2. The method for measuring the voltage drop of the RDDS parameter of a high-voltage circuit breaker according to claim 1, characterized in that: The electrical parameters of the power grid used for transient calculations include: power supply capacity, power supply impedance, load impedance, and actual closing phase of the circuit breaker.

3. The method for measuring the voltage drop of the RDDS parameter of a high-voltage circuit breaker according to claim 1, characterized in that: The closing target time interval of the circuit breaker phase selection closing operation determined according to the voltage zero-crossing time is expressed as [t0-τ, t0+τ], where t0 is the voltage zero-crossing time.

4. The method for measuring the voltage drop of the RDDS parameter of a high-voltage circuit breaker according to claim 1, characterized in that: When executing the phase-selecting closing operation of the circuit breaker, the mechanical closing moment of the main contacts of the circuit breaker is determined through the auxiliary break of the circuit breaker as the closing moment of the circuit breaker.

5. The method for measuring the voltage drop of the RDDS parameter of a high-voltage circuit breaker according to claim 4, characterized in that: At the test voltage kU e When the voltage zero point is used as the target closing phase, M phase-selective closing operations of the circuit breaker are performed, among which the phase-selective closing operations whose closing moment of the circuit breaker is within the closing target time interval are recorded as valid operations, and the number of valid operations is N. The phase-selective closing operations whose mechanical closing moment of the main contacts of the circuit breaker and the moment of the current mutation of the branch where the circuit breaker is located are both within the closing target time interval are recorded as successful operations, and the number of successful operations is n.

6. The method for measuring the voltage drop of RDDS parameters of a high-voltage circuit breaker according to claim 1, characterized in that: The rate of change of the test voltage at the voltage zero point is used as the reference value for calculating RDDS.

7. The method for measuring the voltage drop of RDDS parameters of a high-voltage circuit breaker according to claim 6, characterized in that: The lower limit of RDDS is calculated using the following relationship: In the formula, k RDDS is the lower limit of RDDS, kU e is the effective value of the test voltage, U e is the effective value of the circuit breaker rated voltage, and ω is the test power angular frequency.

8. The method for measuring the voltage drop of RDDS parameters of a high-voltage circuit breaker according to claim 6, characterized in that: The probability that the RDDS of the circuit breaker is greater than the lower limit is calculated using the following relationship: Where p is the probability that the RDDS of the circuit breaker is greater than the lower limit, n is the cumulative sum of the number of successful operations under each test voltage, and N is the cumulative sum of the number of effective operations under each test voltage.

9. A terminal comprising a processor and a storage medium; characterized in that: The storage medium is used to store instructions; The processor is configured to operate according to the instructions to execute the steps of the method according to any one of claims 1 to 8.

10. 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 8 are implemented.

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