Electric arc parameter estimation method and device for direct-current arc

Abstract

The embodiment of the invention discloses an arc parameter estimation method and device for a direct-current arc, and the method comprises the steps: carrying out a direct-current arc open-circuit experiment according to a preset direct-current arc open-circuit experiment circuit, and setting the product of arc parameters in a Mayr arc model equation as a preset value, the arc parameters are an arc time constant and arc power loss, then introducing the arc input power of the unit length of an arc column obtained based on an experiment into a Mayr arc model equation, and adjusting the arc parameters through iterative calculation based on the preset value, and determining the arc parameter obtained at the moment as an arc parameter estimation result until the arc resistance obtained according to the Mayr arc model equation is consistent with the arc resistance per unit length of the arc column obtained based on the experiment. According to the method, the arc parameters of the Mayr model suitable for the alternating-current arc are estimated, and a feasible scheme is provided for current interruption analysis of the alternating-current arc.

Description

Technical Field

[0001] The present invention relates to the field of direct current arc technology, and in particular to an arc parameter estimation method and device for direct current arcs. Background Art

[0002] In recent years, due to the promotion and use of renewable energy and the demand for information and communication technology (ICT), DC distribution systems have been developed in photovoltaic and offshore wind power generation systems. In these cases, DC circuit breaker technology is an important technical element for the safe and reliable use of DC systems. At present, for AC arcs, the Mayr model can be used for current interruption analysis. However, the Mayr model is not well applicable to AC arcs. How to estimate the arc parameters of the Mayr model that can be applied to AC arcs so that the Mayr model can be applied to the current interruption analysis of AC arcs is a problem that the existing technology urgently needs to solve. Summary of the invention

[0003] In order to solve at least one technical problem in the above-mentioned background technology, the present invention proposes an arc parameter estimation method and device for a DC arc.

[0004] In order to achieve the above object, according to one aspect of the present invention, a method for estimating arc parameters for a DC arc is provided, the method comprising:

[0005] A DC arc breaking experiment is performed according to a preset DC arc breaking experiment circuit to obtain experimental data, which includes: arc voltage v arc (t) and arc current i(t), t represents time;

[0006] According to the arc voltage v arc (t) and the arc current i(t) determine the arc resistance r per unit length of the arc column obtained based on the experiment u (t) and the arc input power per unit length of the arc column obtained based on the experiment u (t);

[0007] The product of the arc parameters in the Mayr arc model equation is set to a preset value, wherein the arc parameters are the arc time constant θ and the arc power loss N0, and then the arc input power P per unit length of the arc column obtained based on the experiment is set to a preset value. u (t) Substitute the Mayr arc model equation into the arc model equation, and adjust the arc parameters by iterative calculation based on the preset values ​​until the arc resistance obtained according to the Mayr arc model equation is equal to the arc resistance per unit length of the arc column obtained based on the experiment. u (t) is consistent, and the arc parameters obtained at this time are determined as arc parameter estimation results.

[0008] Optionally, the arc parameter estimation method for a DC arc further includes:

[0009] Based on the arc parameter estimation result, the DC arc circuit breaking process under different circuit conditions is simulated to obtain simulation results, which include: simulated arc voltage and simulated arc current.

[0010] Optionally, the arc parameter estimation method for a DC arc further includes:

[0011] According to the arc current i(t) and the arc parameter estimation result, the relationship between the time variation of the arc parameter and the transient arc current is determined, and then the characteristics of the arc parameter under different circuit conditions are studied based on the relationship.

[0012] Optionally, the DC arc circuit breaking test circuit includes: an arc extinguishing device, a DC power supply, a resistor, an inductor and a switch; the arc extinguishing device is connected in series with the resistor, the inductor, the switch and the DC power supply; the arc extinguishing device includes: a fixed electrode and a movable electrode; during the experiment, the movable electrode starts to contact with the fixed electrode and moves away from the fixed electrode at a uniform speed until the distance between the movable electrode and the fixed electrode reaches a preset distance.

[0013] Alternatively, the Mayr arc model equation is:

[0014]

[0015] Among them, r u is the arc resistance, θ is the arc time constant, N0 is the arc power loss, P u is the arc input power.

[0016] In order to achieve the above object, according to another aspect of the present invention, there is provided an arc parameter estimation device for a DC arc, the device comprising:

[0017] The DC arc circuit breaking test unit is used to perform a DC arc circuit breaking test according to a preset DC arc circuit breaking test circuit to obtain test data, which includes: arc voltage v arc (t) and arc current i(t), t represents time;

[0018] The arc column parameter calculation unit is used to calculate the arc column parameter according to the arc voltage v arc (t) and the arc current i(t) determine the arc resistance r per unit length of the arc column obtained based on the experiment u (t) and the arc input power per unit length of the arc column obtained based on the experiment u (t);

[0019] The arc parameter estimation result determination unit is used to set the product of the arc parameters in the Mayr arc model equation to a preset value, wherein the arc parameters are the arc time constant θ and the arc power loss N0, and then set the arc input power P per unit length of the arc column obtained based on the experiment u (t) Substitute the Mayr arc model equation into the arc model equation, and adjust the arc parameters by iterative calculation based on the preset values ​​until the arc resistance obtained according to the Mayr arc model equation is equal to the arc resistance per unit length of the arc column obtained based on the experiment. u (t) is consistent, and the arc parameters obtained at this time are determined as arc parameter estimation results.

[0020] Optionally, the arc parameter estimation device for DC arc further includes:

[0021] The DC arc breaking process simulation unit is used to simulate the DC arc breaking process based on the arc parameter estimation result to obtain a simulation result, wherein the simulation result includes: a simulated arc voltage and a simulated arc current.

[0022] Optionally, the arc parameter estimation device for DC arc further includes:

[0023] The arc parameter characteristic research unit is used to determine the relationship between the time variation of the arc parameter and the transient arc current according to the arc current i(t) and the arc parameter estimation result, and then study the characteristics of the arc parameter under different circuit conditions according to the relationship.

[0024] In order to achieve the above-mentioned purpose, according to another aspect of the present invention, a computer device is also provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned arc parameter estimation method for DC arcs when executing the computer program.

[0025] In order to achieve the above-mentioned purpose, according to another aspect of the present invention, a computer-readable storage medium is further provided, on which a computer program / instruction is stored, and when the computer program / instruction is executed by a processor, the steps of the above-mentioned arc parameter estimation method for DC arcs are implemented.

[0026] In order to achieve the above-mentioned purpose, according to another aspect of the present invention, a computer program product is further provided, including a computer program / instruction, which implements the steps of the above-mentioned arc parameter estimation method for DC arcs when executed by a processor.

[0027] The beneficial effects of the present invention are:

[0028] The embodiment of the present invention performs a DC arc circuit breaking experiment through a DC arc circuit breaking experimental circuit to obtain experimental data, and then obtains arc parameter estimation results through iterative calculation based on the experimental data, thereby estimating the arc parameters of the Mayr model that can be applicable to AC arcs, so that the Mayr model can be applied to the current interruption analysis of AC arcs, providing a feasible solution for the current interruption analysis of AC arcs. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0030] Figure 1 Schematic diagram of a DC arc circuit breaking test circuit according to an embodiment of the present invention;

[0031] Figure 2 is a flow chart of an arc parameter estimation method for a DC arc according to an embodiment of the present invention;

[0032] Figure 3 is a structural block diagram of an arc parameter estimation device for a DC arc according to an embodiment of the present invention;

[0033] Figure 4 It is a schematic diagram of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0035] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product 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.

[0036] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or apparatus.

[0037] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0038] Figure 2 is a flow chart of an arc parameter estimation method for a DC arc according to an embodiment of the present invention. Figure 2 As shown, in one embodiment of the present invention, the arc parameter estimation method for DC arc of the present invention includes steps S101 to S103.

[0039] Step S101, performing a DC arc breaking test according to a preset DC arc breaking test circuit to obtain experimental data, the experimental data including: arc voltage v arc (t) and arc current i(t), where t represents time.

[0040] Figure 1 A schematic diagram of a DC arc circuit breaker experiment is shown. Figure 1 As shown, in one embodiment of the present invention, the DC arc circuit breaking test circuit comprises: an arc extinguishing device 1, a DC power supply E, a resistor R, an inductor L and a switch S; the arc extinguishing device 1 is connected in series with the resistor R, the inductor L, the switch S and the DC power supply E. The arc extinguishing device 1 comprises: a movable electrode 11, a fixed electrode 12 and an electromagnetic coil 13; during the experiment, the movable electrode 11 starts to contact with the fixed electrode 12 and moves away from the fixed electrode 12 at a uniform speed until the distance between the movable electrode 11 and the fixed electrode 12 reaches a preset distance.

[0041] like Figure 1 As shown, the arc extinguishing device 1 of the present invention has a simple structure, wherein the movable electrode 11 is the anode and the fixed electrode 12 is the cathode. In addition, a copper rod with a diameter of 5-15 mm is used as an electrode. In our experiment, at t=0ms, the anode electrode head is in contact with the cathode. Then, it moves upward through the electromagnetic coil 13 at an average speed of about 1-2m / s. The anode keeps moving upward until the electrode spacing reaches 20-40mm. Multiple current interruption tests were carried out under each condition.

[0042] The DC current interruption test was conducted for three DC currents IDC of 3A, 10A and 15A under the circuit conditions of no inductance L, 2-4mH and 6-8mH respectively. Due to the three-phase bridge rectifier circuit, the DC supply voltage fluctuates.

[0043] In one embodiment of the present invention, the present invention measures the waveforms of arc voltage varc(t) and current i(t) when interrupting a 15A DC current IDC under the circuit condition of an inductance L of 3.3 millihenries, and the result is that at t=0 milliseconds, the electrodes begin to open, and their separation distance reaches 25-35 mm at about t=35 milliseconds. After that, the anode stops moving.

[0044] By measuring the waveforms of the arc voltage varc(t) and the current i(t), it is found that at t = 0 milliseconds, the arc voltage suddenly increases from 0 to 10-20 volts, which corresponds to the electrode drop voltage. With the sudden increase in the arc voltage, the current instantly decreases from about 30-20 amperes to 20-15 amperes. After that, the current gradually decreases with the increase in the arc voltage until about t = 20 milliseconds. After t = 20 milliseconds, the arc voltage begins to increase rapidly, causing the current to drop rapidly to zero at t = 35 milliseconds. At this point, the current interruption is successfully achieved.

[0045] Step S102, according to the arc voltage v arc (t) and the arc current i(t) determine the arc resistance r per unit length of the arc column obtained based on the experiment u (t) and the arc input power per unit length of the arc column obtained based on the experiment u (t).

[0046] The arc voltage is affected not only by the transient behavior of the arc column, but also by the distance between the electrodes. To ensure generality, we decided to study the characteristics of the arc column per unit length. Assuming that a straight arc column with uniform length is established between the electrodes, the arc voltage per unit length of the arc column v u , arc resistance per unit length of arc column r u and the arc input power per unit length of the arc column P u The formulas are as follows:

[0047]

[0048]

[0049] P u (t) = v u (t)i(t) Formula (3)

[0050] Among them, v ele is the voltage of the DC power supply E.

[0051] Step S103, setting the product of arc parameters in the Mayr arc model equation to a preset value, wherein the arc parameters are the arc time constant θ and the arc power loss N0, and then setting the arc input power P per unit length of the arc column obtained based on the experiment to a preset value. u (t) Substitute the Mayr arc model equation into the arc model equation, and adjust the arc parameters by iterative calculation based on the preset values ​​until the arc resistance obtained according to the Mayr arc model equation is equal to the arc resistance per unit length of the arc column obtained based on the experiment. u (t) is consistent, and the arc parameters obtained at this time are determined as arc parameter estimation results.

[0052] For AC arc, the Cassie model, Mayr model and modifications of these models have been used to perform current interruption analysis. The Mayr model is particularly suitable for analyzing AC arc behavior close to the current zero point and is often used for simple analysis of AC current interruption. In the present invention, we use the Mayr model to estimate the arc parameters of the transient behavior of the arc column during DC current interruption.

[0053] The Mayr arc model equation is:

[0054]

[0055] Among them, r u is the arc resistance, θ is the arc time constant, N0 is the arc power loss, P u is the arc input power.

[0056] The simplest application of the Mayr model considers the arc parameters as constants that do not vary with time. However, it may be possible to successfully explain the actual behavior by considering that the arc parameters vary every second. Therefore, the product of the arc time constant θ[s] and the arc power loss N0[W / mm], Q[J / mm], is constant, and a set of time-varying θ[s] and N0[W / mm] are estimated from the measured arc voltage and current waveforms for various Q values. For a given Q value, θ[s] and N0[W / mm] are adjusted by iterative calculations so that r obtained according to the Mayr equation is u The measured value at each time point (i.e. the arc resistance per unit length of the arc column obtained based on the experiment above) u (t)) is consistent. The iterative calculation can use the Runge-Kutta method to obtain the numerical solution of formula (4).

[0057] It can be seen that the embodiment of the present invention performs a DC arc circuit breaking experiment through a DC arc circuit breaking experimental circuit to obtain experimental data, and then obtains arc parameter estimation results through iterative calculation based on the experimental data, thereby estimating the arc parameters of the Mayr model that can be applicable to AC arcs, so that the Mayr model can be applicable to the current interruption analysis of AC arcs, and provides a feasible solution for the current interruption analysis of AC arcs.

[0058] In one embodiment of the present invention, the arc parameter estimation method for DC arc of the present invention further includes:

[0059] According to the arc current i(t) and the arc parameter estimation result, the relationship between the time variation of the arc parameter and the transient arc current is determined, and then the characteristics of the arc parameter under different circuit conditions are studied based on the relationship.

[0060] In one embodiment of the present invention, the present invention studies the relationship between the time variation of arc parameters and the transient arc current, and then studies the characteristics of arc parameters under different circuit conditions based on the relationship, and draws the following conclusions through the study:

[0061] 1. By considering arc parameters as functions of current, the dispersion of each shot is nearly eliminated.

[0062] 2. As Q increases, both the arc power loss and the arc time constant are calculated to be larger.

[0063] 3. In the area where the current decreases from about 15 amperes to 9 amperes, the arc power loss shows almost the same characteristics even if Q is different. Correspondingly, the arc time constant increases with the increase of Q.

[0064] 4. Near the current zero point, the arc time constant shows the same characteristics regardless of the value of Q. Correspondingly, the larger the value of Q, the greater the arc power loss.

[0065] 5. In the case of Q = 0.1 J / mm, the time constant is very large; exceeding several thousand microseconds except near current zero. On the other hand, in the case of Q = 0.001 J / mm, the time constant is less than 100 microseconds.

[0066] In one embodiment of the present invention, the present invention also studies the arc parameter function of the transient arc current under different circuit conditions. The characteristics of the arc column per unit length are obtained for the waveforms measured for different DC currents IDC and inductances L, and then the arc parameters are estimated using the calculation method shown in the above step S103.

[0067] In one embodiment of the present invention, the arc parameter estimation method for DC arc of the present invention further includes:

[0068] Based on the arc parameter estimation result, the DC arc circuit breaking process under different circuit conditions is simulated to obtain simulation results, which include: simulated arc voltage and simulated arc current.

[0069] In one embodiment of the present invention, the present invention can also construct a DC arc black box model. As a first step, a DC circuit breaking experiment was conducted to analyze the DC circuit breaking process to obtain arc parameters (i.e., arc parameter estimation results) based on the modified Mayr arc model. As a second step, we used the estimated arc parameters to predict the current interruption process under different circuit conditions to study the usefulness of the arc parameters.

[0070] First, the simulation model for predicting the current interruption process is determined. Figure 1 The transient behavior of the current i flowing in the circuit shown is expressed as follows:

[0071]

[0072] v arc (t) = r u (t)d(t)i(t)+v ele Formula (6)

[0073] Among them, v arc is the given arc voltage.

[0074] If the estimated arc parameters (i.e., arc parameter estimation results) obtained in the above step S103 have high versatility, the current interruption process under different experimental conditions can be predicted by simultaneously solving formula (4), formula (5), and formula (6). Therefore, in the present invention, we use the arc parameter estimation results obtained in the above step S103 for IDC=20A and L=3.3 millihenry to simulate the current interruption process of IDC=5A and 10A.

[0075] The present invention studies the reconstruction of the current interruption process under different circuit conditions. Under the condition of inductance L = 3.3 millihenry, the current interruption process under different circuit conditions of IDC = 5 amperes and 10 amperes was reconstructed. After reconstruction, it was found that the simulated waveform was almost the same as the measured waveform.

[0076] It can be seen from the above embodiments that the solution of the present invention makes at least the following contributions:

[0077] In the technical solution of the present invention, current interruption experiments of 3 amperes, 10 amperes and 15 amperes were carried out on circuits with a supply voltage of 120 volts and inductances of no inductance, 2-4 millihenry and 6-8 millihenry. The arc voltage is affected not only by the transient behavior of the arc column, but also by the distance between the electrodes. In order to ensure universality, it was decided to study the characteristics of the arc column per unit length.

[0078] The technical solution of the present invention obtains the arc resistance and arc input power per unit length of the arc column in order to estimate the arc parameters using the modified Mayr model. The product Q of the arc parameters is assumed to be constant. By using the current function of Q=0.02 joules / mm as the arc parameter, the DC current interruption process of IDC=5 amperes, 10 amperes and L=3.3 millihenry is successfully predicted.

[0079] In addition, the technical solution of the present invention also studies the dependence of the arc circuit breaking process on the circuit inductance and the separation speed between electrodes. The results show that the arc overvoltage increases proportionally with the size of the circuit inductance. It is also confirmed that the separation speed between electrodes does not affect the arc overvoltage.

[0080] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0081] Based on the same inventive concept, an embodiment of the present invention further provides an arc parameter estimation device for DC arcs, which can be used to implement the arc parameter estimation method for DC arcs described in the above embodiments, as described in the following embodiments. Since the principle of solving the problem by the arc parameter estimation device for DC arcs is similar to that of the arc parameter estimation method for DC arcs, the embodiments of the arc parameter estimation device for DC arcs can refer to the embodiments of the arc parameter estimation method for DC arcs, and the repeated parts will not be repeated. As used below, the terms "unit" or "module" can be a combination of software and / or hardware that implements predetermined functions. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceived.

[0082] Figure 3 is a structural block diagram of an arc parameter estimation device for a DC arc according to an embodiment of the present invention. Figure 3 As shown, in one embodiment of the present invention, the arc parameter estimation device for DC arc of the present invention comprises:

[0083] The DC arc circuit breaking test unit 201 is used to perform a DC arc circuit breaking test according to a preset DC arc circuit breaking test circuit to obtain test data, wherein the test data includes: arc voltage v arc (t) and arc current i(t), t represents time;

[0084] The arc column parameter calculation unit 202 is used to calculate the arc column parameter according to the arc voltage v arc(t) and the arc current i(t) determine the arc resistance r per unit length of the arc column obtained based on the experiment u (t) and the arc input power per unit length of the arc column obtained based on the experiment u (t);

[0085] The arc parameter estimation result determination unit 203 is used to set the product of the arc parameters in the Mayr arc model equation to a preset value, wherein the arc parameters are the arc time constant θ and the arc power loss N0, and then set the arc input power P per unit length of the arc column obtained based on the experiment u (t) Substitute the Mayr arc model equation into the arc model equation, and adjust the arc parameters by iterative calculation based on the preset values ​​until the arc resistance obtained according to the Mayr arc model equation is equal to the arc resistance per unit length of the arc column obtained based on the experiment. u (t) is consistent, and the arc parameters obtained at this time are determined as arc parameter estimation results.

[0086] In one embodiment of the present invention, the arc parameter estimation device for DC arc of the present invention further includes:

[0087] The DC arc breaking process simulation unit is used to simulate the DC arc breaking process based on the arc parameter estimation result to obtain a simulation result, wherein the simulation result includes: a simulated arc voltage and a simulated arc current.

[0088] In one embodiment of the present invention, the arc parameter estimation device for DC arc of the present invention further includes:

[0089] The arc parameter characteristic research unit is used to determine the relationship between the time variation of the arc parameter and the transient arc current according to the arc current i(t) and the arc parameter estimation result, and then study the characteristics of the arc parameter under different circuit conditions according to the relationship.

[0090] In one embodiment of the present invention, the DC arc circuit breaking test circuit includes: an arc extinguishing device, a DC power supply, a resistor, an inductor and a switch; the arc extinguishing device is connected in series with the resistor, the inductor, the switch and the DC power supply; the arc extinguishing device includes: a fixed electrode and a movable electrode; during the experiment, the movable electrode starts to contact with the fixed electrode and moves away from the fixed electrode at a uniform speed until the distance between the movable electrode and the fixed electrode reaches a preset distance.

[0091] In one embodiment of the present invention, the Mayr arc model equation is:

[0092]

[0093] Among them, ru is the arc resistance, θ is the arc time constant, N0 is the arc power loss, P u is the arc input power.

[0094] In order to achieve the above object, according to another aspect of the present application, a computer device is also provided. Figure 4 As shown, the computer device includes a memory, a processor, a communication interface and a communication bus. A computer program that can be executed on the processor is stored in the memory. When the processor executes the computer program, the steps in the above-mentioned embodiment method are implemented.

[0095] The processor may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0096] The memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer executable programs and units, such as the corresponding program units in the above method embodiments of the present invention. The processor executes various functional applications of the processor and works data processing by running the non-transitory software programs, instructions and modules stored in the memory, that is, implementing the method in the above method embodiments.

[0097] The memory may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created by the processor, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0098] The one or more units are stored in the memory, and when executed by the processor, the method in the above embodiment is performed.

[0099] The specific details of the above-mentioned computer device can be understood by referring to the corresponding related descriptions and effects in the above-mentioned embodiments, and will not be repeated here.

[0100] In order to achieve the above purpose, according to another aspect of the present application, a computer-readable storage medium is also provided, wherein the computer-readable storage medium stores a computer program, and the computer program implements the steps in the above-mentioned arc parameter estimation method for DC arcs when executed in a computer processor. Those skilled in the art can understand that the implementation of all or part of the processes in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and the program can include the processes of the embodiments of the above-mentioned methods when executed. Among them, the storage medium can be a disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory (Flash Memory), a hard disk (Hard Disk Drive, abbreviated as: HDD) or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above-mentioned types of memory.

[0101] In order to achieve the above-mentioned purpose, according to another aspect of the present application, a computer program product is also provided, including a computer program / instruction, which implements the steps of the above-mentioned arc parameter estimation method for DC arcs when executed by a processor.

[0102] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, and optionally, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for estimating arc parameters for a DC arc, characterized in that: include: A DC arc breaking experiment is performed according to a preset DC arc breaking experiment circuit to obtain experimental data, which includes: arc voltage v arc (t) and arc current i(t), t represents time; According to the arc voltage v arc (t) and the arc current i(t) determine the arc resistance r per unit length of the arc column obtained based on the experiment u (t) and the arc input power per unit length of the arc column obtained based on the experiment u (t); The product of the arc parameters in the Mayr arc model equation is set to a preset value, wherein the arc parameters are the arc time constant θ and the arc power loss N0, and then the arc input power P per unit length of the arc column obtained based on the experiment is set to a preset value. u (t) Bringing the Mayr arc model equation into the equation, and adjusting the arc parameters by iterative calculation based on the preset values, until the arc resistance obtained according to the Mayr arc model equation is equal to the arc resistance per unit length of the arc column obtained based on the experiment. u (t) is consistent, and the arc parameters obtained at this time are determined as arc parameter estimation results.

2. The arc parameter estimation method for DC arc according to claim 1, characterized in that: Also includes: Based on the arc parameter estimation result, the DC arc circuit breaking process under different circuit conditions is simulated to obtain simulation results, which include: simulated arc voltage and simulated arc current.

3. The arc parameter estimation method for DC arc according to claim 1, characterized in that: Also includes: According to the arc current i(t) and the arc parameter estimation result, the relationship between the time variation of the arc parameter and the transient arc current is determined, and then the characteristics of the arc parameter under different circuit conditions are studied based on the relationship.

4. The arc parameter estimation method for DC arc according to claim 1, characterized in that: The DC arc circuit breaking test circuit comprises: an arc extinguishing device, a DC power supply, a resistor, an inductor and a switch; the arc extinguishing device is connected in series with the resistor, the inductor, the switch and the DC power supply; the arc extinguishing device comprises: a fixed electrode and a movable electrode; during the experiment, the movable electrode starts to contact with the fixed electrode and moves away from the fixed electrode at a uniform speed until the distance between the movable electrode and the fixed electrode reaches a preset distance.

5. The arc parameter estimation method for DC arc according to claim 1, characterized in that: The Mayr arc model equation is: Among them, r u is the arc resistance, θ is the arc time constant, N0 is the arc power loss, P u is the arc input power.

6. An arc parameter estimation device for DC arc, characterized in that: include: The DC arc circuit breaking test unit is used to perform a DC arc circuit breaking test according to a preset DC arc circuit breaking test circuit to obtain test data, which includes: arc voltage v arc (t) and arc current i(t), t represents time; The arc column parameter calculation unit is used to calculate the arc column parameter according to the arc voltage v arc (t) and the arc current i(t) determine the arc resistance r per unit length of the arc column obtained based on the experiment u (t) and the arc input power per unit length of the arc column obtained based on the experiment u (t); The arc parameter estimation result determination unit is used to set the product of the arc parameters in the Mayr arc model equation to a preset value, wherein the arc parameters are the arc time constant θ and the arc power loss N0, and then set the arc input power P per unit length of the arc column obtained based on the experiment u (t) Bringing the Mayr arc model equation into the equation, and adjusting the arc parameters by iterative calculation based on the preset values, until the arc resistance obtained according to the Mayr arc model equation is equal to the arc resistance per unit length of the arc column obtained based on the experiment. u (t) is consistent, and the arc parameters obtained at this time are determined as arc parameter estimation results.

7. The arc parameter estimation device for DC arc according to claim 6, characterized in that: Also includes: The DC arc breaking process simulation unit is used to simulate the DC arc breaking process based on the arc parameter estimation result to obtain a simulation result, wherein the simulation result includes: a simulated arc voltage and a simulated arc current.

8. The arc parameter estimation device for DC arc according to claim 6, characterized in that: Also includes: The arc parameter characteristic research unit is used to determine the relationship between the time variation of the arc parameter and the transient arc current according to the arc current i(t) and the arc parameter estimation result, and then study the characteristics of the arc parameter under different circuit conditions according to the relationship.

9. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

10. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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