Method for selecting silicon carbide valve plates for de-excitation of generator

Abstract

The invention relates to the technical field of silicon carbide valve plates for de-excitation of generators, in particular to a method for selecting silicon carbide valve plates for de-excitation of generators, which comprises the following steps of: setting working parameters; obtaining target data, wherein the target data comprises reference data and characteristic data; preliminarily screening the valve plates according to the target data to obtain a first target valve plate; calculating the first target valve plate to obtain the area of the region; and performing secondary screening on the first target valve plate according to the area of the region to obtain a target combination. The method has the advantages that magnetic field energy stored in a generator rotor can be quickly transferred and consumed to avoid damage to the generator, meanwhile, a good flow equalizing effect can be guaranteed within the working range of the silicon carbide valve plates, the influence of large individual data measurement deviation on the flow equalizing effect is eliminated, the valve plate combination dispersity is greatly reduced, and the service life of the valve plate is prolonged. And the current sharing effect is improved. And the current-sharing coefficient of the silicon carbide field suppression resistor reaches over 0.95.

Description

Technical Field

[0001] The present invention relates to the technical field of silicon carbide varistors for generator field suppression, and particularly to a method for selecting silicon carbide varistors for generator field suppression. Background Art

[0002] In modern power systems, the stable operation of giant generator sets is crucial for ensuring the reliability of power supply. When an electrical accident occurs in a generator set, the role of the field suppression system is to quickly transfer the magnetic field energy stored in the generator rotor to avoid damage to the generator. The field suppression switch and the silicon carbide field suppression resistor are key components to achieve this function, and the silicon carbide field suppression resistor protects the safety of the generator by quickly absorbing the energy in the rotor.

[0003] The silicon carbide field suppression resistor is composed of a large number of silicon carbide varistors connected in series and parallel, and its performance directly affects the efficiency and reliability of the field suppression system. The traditional method for selecting silicon carbide varistors is mainly based on the rated operating point. Although this method can ensure a good current sharing effect near the rated operating point, during an electrical accident in the generator set, it is often not at the rated operating point of the silicon carbide varistor. Due to the non-linear characteristics of the silicon carbide varistor, the greater the distance from the rated operating point, the greater the dispersion of the obtained varistor combination and the worse the current sharing effect. To ensure the reliability of the generator field suppression, it is necessary to increase the standby capacity, which leads to an increase in the cost and volume of the field suppression resistor. Summary of the Invention

[0004] The purpose of this part is to outline some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Simplifications or omissions may be made in this part, as well as in the abstract and title of the present application, to avoid obscuring the purpose of this part, the abstract, and the title, and such simplifications or omissions shall not be used to limit the scope of the present invention.

[0005] In view of the above existing problems, the present invention is proposed.

[0006] Therefore, the present invention provides a method for selecting silicon carbide varistors for generator field suppression, which can solve the problems mentioned in the background art.

[0007] To solve the above technical problems, the present invention provides the following technical solutions:

[0008] In a first aspect, the present invention provides a method for selecting silicon carbide varistors for generator field suppression, including determining a working range through working parameters;

[0009] Obtaining target data, where the target data includes reference data and characteristic data;

[0010] Performing a preliminary screening of the varistors according to the target data and obtaining a first target varistor;

[0011] By calculating the first target valve disc, the area of the region is obtained.

[0012] According to the area of the region, the first target valve disc is secondarily screened to obtain the target combination.

[0013] As a preferred scheme of the method for selecting a silicon carbide valve disc for generator field suppression according to the present invention, wherein: the determining the working range through the working parameters includes,

[0014] By referring to the deviation △U parameter allowed by the reference voltage, the working range of the silicon carbide valve disc is determined to be I1 - I2.

[0015] As a preferred scheme of the method for selecting a silicon carbide valve disc for generator field suppression according to the present invention, wherein: the reference data is the current-reference voltage relationship curve;

[0016] The current-reference voltage relationship curve is a relationship curve formed by connecting the current at each point within the range of I1 - I2 and its corresponding reference voltage value.

[0017] As a preferred scheme of the method for selecting a silicon carbide valve disc for generator field suppression according to the present invention, wherein: the characteristic data is the current-voltage characteristic curve;

[0018] The current-voltage characteristic curve is a characteristic curve formed by connecting the current at each point within the range of I1 - I2 and its corresponding voltage value for each silicon carbide valve disc.

[0019] As a preferred scheme of the method for selecting a silicon carbide valve disc for generator field suppression according to the present invention, wherein: the initially screening the valve discs according to the target data to obtain the first target valve disc includes,

[0020] Comparing the current-voltage characteristic curve of each silicon carbide valve disc with the current-reference voltage relationship curve, and screening out the silicon carbide valve discs with the absolute value of the deviation within the range of I1 - I2 less than △U as the first target valve discs.

[0021] As a preferred scheme of the method for selecting a silicon carbide valve disc for generator field suppression according to the present invention, wherein: calculating the area Sn of the region enclosed between the current-voltage characteristic curve and the current-reference voltage relationship curve of the valve disc within the working range according to the first target valve disc;

[0022] The area Sn of the region is the area of the closed figure formed by the A point and the D point on the current-reference voltage relationship curve corresponding to the abscissas of I1 and I2, and the B point and the C point on the current-voltage characteristic curve corresponding to the abscissas of I1 and I2;

[0023] The area of the closed figure is formed by connecting points in sequence according to the order of point A - point B - point C - point D - point A;

[0024] Among them, the area Sn of the region is calculated by integrating the absolute value of the difference between the measured characteristic curve voltage and the reference characteristic curve voltage of each first target valve piece corresponding to the working point within the working range.

[0025] As a preferred scheme of the method for selecting valve pieces of silicon carbide valve pieces for generator field suppression according to the present invention, wherein: the secondary screening of the first target valve pieces according to the area of the region includes,

[0026] Sort each first target valve piece whose area Sn of the region is calculated by absolute value integration in ascending order of the area Sn of the region, and sequentially screen out the required number of valve pieces to form a target combination.

[0027] In a second aspect, the present invention provides a method for selecting valve pieces of silicon carbide valve pieces for generator field suppression, including: a target data acquisition module, configured to acquire reference voltage data to obtain a current - reference voltage relationship curve and input the current and corresponding voltage data of each silicon carbide valve piece within the working range to obtain a current - voltage characteristic curve;

[0028] A screening module, configured to compare the current - voltage characteristic curve of the silicon carbide valve piece with the current - reference voltage relationship curve and screen out the valve pieces with a deviation less than ΔU;

[0029] A result acquisition module, configured to sort according to the calculated area Sn of each valve piece in ascending order and screen out the required number of valve pieces to form a target combination.

[0030] In a third aspect, the present invention provides a computer device, including a memory and a processor, where the memory stores a computer program, and when the processor executes the computer program, the steps of the method described above are implemented.

[0031] In a fourth aspect, the present invention provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the method described above are implemented.

[0032] Compared with the prior art, the beneficial effects of the present invention: It can quickly transfer and consume the magnetic field energy stored in the generator rotor to avoid damage to the generator. At the same time, it can ensure a good current sharing effect within the working range of the silicon carbide valve piece, eliminate the influence of large measurement deviations of individual data on the current sharing effect, greatly reduce the dispersion of the valve piece combination, and improve the current sharing effect. The current sharing coefficient of the silicon carbide field suppression resistor reaches more than 0.95. Description of the Drawings

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. Among them:

[0034] Figure 1 It is a schematic diagram of the operation steps of the method for selecting silicon carbide varistors for generator field suppression.

[0035] Figure 2 It is a schematic diagram of the preliminary voltage screening of the method for selecting silicon carbide varistors for generator field suppression.

[0036] Figure 3 It is a schematic diagram of the target combination screening of the method for selecting silicon carbide varistors for generator field suppression.

[0037] Figure 4 It is a schematic diagram of the internal structure of a computer device. Specific Embodiments

[0038] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following will provide a detailed description of the specific embodiments of the present invention with reference to the accompanying drawings of the specification.

[0039] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar generalizations without departing from the spirit of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0040] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that can be included in at least one implementation of the present invention. The appearances of "in one embodiment" in different places in this specification do not all refer to the same embodiment, nor are they separate or alternative embodiments that exclude each other with other embodiments.

[0041] Embodiment 1

[0042] Referring to Figures 1 to 3 , it is the first embodiment of the present invention. This embodiment provides a method for selecting silicon carbide varistors for generator field suppression, which includes

[0043] S1. Determine the working range through working parameters.

[0044] Further, determining the working range through working parameters includes

[0045] Determine the operating range of the silicon carbide varistor as I1 - I2 based on the deviation △U parameter of the reference voltage.

[0046] It should be noted that the operating range I1 - I2 of the silicon carbide varistor is designed according to the unit parameters, and within the current range of I1 - I2, the operating range of the silicon carbide varistor should include at least 3 operating points to determine the characteristic curve of the silicon carbide varistor. The more operating points, the greater the calculation amount of selecting the varistor, the smaller the influence brought by the data measurement deviation, and the better the effect of selecting the varistor.

[0047] Among them, the deviation △U is not a fixed value and can be adjusted according to the actual situation.

[0048] S2. Obtain the target data, where the target data includes reference data and characteristic data.

[0049] Furthermore, the reference data is the current - reference voltage relationship curve.

[0050] The current - reference voltage relationship curve is a relationship curve formed by collecting the current at each point within the range of I1 - I2 and its corresponding reference voltage value.

[0051] It should be noted that for each point of the silicon carbide varistor, with the current as the abscissa and the voltage as the ordinate, establish the current - reference voltage relationship curve a of the silicon carbide varistor.

[0052] Furthermore, the characteristic data is the current - voltage characteristic curve.

[0053] The current - voltage characteristic curve is a characteristic curve formed by collecting the current at each point within the range of I1 - I2 and its corresponding voltage value for each silicon carbide varistor.

[0054] It should be noted that measure the current and corresponding voltage at each point within the current range of I1 - I2 for each silicon carbide varistor to form m current - voltage characteristic curves of the silicon carbide varistors, where m is the total number of silicon carbide varistors for selecting the varistor.

[0055] S3. Conduct a preliminary screening of the varistors based on the target data to obtain the first target varistor.

[0056] Furthermore, conducting a preliminary screening of the varistors based on the target data to obtain the first target varistor includes comparing the current - voltage characteristic curve of each silicon carbide varistor with the current - reference voltage relationship curve, and screening out the silicon carbide varistors with an absolute value of deviation less than △U within the range of I1 - I2 as the first target varistors.

[0057] It should be noted that for the above m current-voltage characteristic curves, within the current range of I1-I2, the difference between the voltage at each point and the reference voltage in the current-reference voltage relationship curve a at the same current is calculated respectively. If the difference is greater than the allowable deviation range △U (curve j), it is excluded. Finally, n curves with the voltage difference within the working range all less than the allowable deviation △U are obtained, and n is the number of initially selected qualified silicon carbide varistors.

[0058] S4. Calculate the area of the region by performing calculations on the first target varistor.

[0059] Furthermore, calculating the area of the region by performing calculations on the first target varistor includes:

[0060] Calculating the area Sn of the region enclosed by the current-voltage characteristic curve and the current-reference voltage relationship curve of the varistor within the working range according to the first target varistor;

[0061] The area of the region Sn is the area of the closed figure formed by point A and point D on the current-reference voltage relationship curve corresponding to the abscissas of I1 and I2, and point B and point C on the current-voltage characteristic curve corresponding to the abscissas of I1 and I2;

[0062] The area of the closed figure is formed by connecting the points in the order of point A - point B - point C - point D - point A in sequence;

[0063] Among them, the area of the region Sn is calculated according to the integral of the absolute value of the difference between the measured characteristic curve voltage and the reference characteristic curve voltage of each first target varistor at the corresponding working points within the working range:

[0064] Sn = ∫I2 I1 |Measured characteristic curve voltage - reference characteristic curve voltage|.

[0065] It can also be calculated according to the integral of the absolute value of the difference between the two curves after fitting the curve according to the voltage-current characteristic curve formula J = CI of the silicon carbide non-linear resistor β after fitting it into a curve.

[0066] It should be noted that for the above n current-voltage characteristic curves, the areas enclosed by each curve and the current-reference voltage relationship curve a within the current range of I1-I2 are calculated, corresponding to S1, S2…Sn;

[0067] S5. Perform a secondary screening on the first target varistor according to the area of the region to obtain a target combination, where the target combination is the optimal combination.

[0068] Furthermore, performing a secondary screening on the first target varistor according to the area of the region includes:

[0069] Arrange each first target disc for calculating the area Sn of the region by absolute value integration in ascending order of the area Sn of the region, and sequentially select the required number of discs to form a target combination.

[0070] It should be noted that if S1, S2…Sn are arranged in ascending order and the required number of discs k is sequentially selected, then the discs corresponding to these k current-voltage characteristic curves are the optimal combination.

[0071] In summary, the beneficial effect of the present invention is that it can ensure a good current sharing effect within the working range of the silicon carbide disc, and at the same time can eliminate the influence of large measurement deviations of individual data on the current sharing effect, greatly reducing the dispersion of the disc combination and improving the current sharing effect. The current sharing coefficient of the silicon carbide excitation suppression resistor reaches more than 0.95.

[0072] Embodiment 2

[0073] This embodiment provides a method for selecting discs of silicon carbide discs for generator excitation suppression, which includes a target data acquisition module for acquiring reference voltage data to obtain a current-reference voltage relationship curve and inputting the current and corresponding voltage data of each silicon carbide disc within the working range to obtain a current-voltage characteristic curve;

[0074] A screening module for comparing the current-voltage characteristic curve of the silicon carbide disc with the current-reference voltage relationship curve and screening out the discs with a deviation less than ΔU;

[0075] A result acquisition module for sorting the calculated area Sn of each disc in ascending order and screening out the required number of discs to form a target combination.

[0076] The above-mentioned unit modules can be embedded in the processor of the computer device in hardware form or independent of it, or stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to the above modules.

[0077] Embodiment 3

[0078] This embodiment provides a computer device, which can be a terminal, and its internal structure diagram can be as Figure 4As shown in the figure. The computer device includes a processor, a memory, a communication interface, a display screen, and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through Wi-Fi, a carrier network, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it realizes a method for selecting a silicon carbide varistor for generator field suppression. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, a trackball, or a touchpad provided on the shell of the computer device, or an external keyboard, a touchpad, or a mouse, etc.

[0079] This embodiment also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it realizes: the acquisition terminal performs time compensation through a synchronization algorithm.

[0080] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A method for selecting a silicon carbide varistor for generator field suppression, characterized in that: including, determining the working range based on working parameters; acquiring target data, where the target data includes reference data and characteristic data; performing a preliminary screening of the valve plates according to the target data and obtaining the first target valve plates; calculating the area of the region by performing calculations on the first target valve plates; performing a secondary screening of the first target valve plates according to the area of the region and obtaining the target combination.

2. The method for selecting a silicon carbide varistor for generator field suppression according to claim 1, characterized in that: The determining the working range based on working parameters includes: determining the working range of the silicon carbide valve plates as I1 - I2 based on the deviation ΔU parameter allowed by the reference voltage.

3. The method for selecting a silicon carbide varistor for generator field suppression according to claim 2, characterized in that: The reference data is the current - reference voltage relationship curve; The current - reference voltage relationship curve is a relationship curve formed by connecting the current values at each point within the range of I1 - I2 and their corresponding reference voltage values collected.

4. The method for selecting a silicon carbide varistor for generator field suppression according to claim 3, characterized in that: The characteristic data is the current - voltage characteristic curve; The current - voltage characteristic curve is a characteristic curve formed by connecting the current values at each point within the range of I1 - I2 and their corresponding voltage values collected for each silicon carbide valve plate.

5. The method for selecting silicon carbide varistor used for generator field suppression according to any one of claims 1 to 4, characterized in that: The performing a preliminary screening of the valve plates according to the target data and obtaining the first target valve plates includes: comparing the current - voltage characteristic curve of each silicon carbide valve plate with the current - reference voltage relationship curve, and screening out the silicon carbide valve plates with the absolute value of the deviation within the range of I1 - I2 being less than ΔU as the first target valve plates.

6. The method for selecting a silicon carbide varistor for generator field suppression according to claim 5, characterized in that: The calculating the area of the region by performing calculations on the first target valve plates includes: calculating the area Sn of the region enclosed between the current - voltage characteristic curve and the current - reference voltage relationship curve of the valve plates within the working range according to the first target valve plates; The area Sn of the region is the area of the closed figure formed by point A and point D on the current - reference voltage relationship curve corresponding to the abscissas of I1 and I2, and point B and point C on the current - voltage characteristic curve corresponding to the abscissas of I1 and I2; The area of the closed figure is formed by connecting in sequence according to the order of point A - point B - point C - point D - point A; wherein, the area Sn of the region is calculated by integrating the absolute value of the difference between the measured characteristic curve voltage and the reference characteristic curve voltage of each first target valve plate at the corresponding working points within the working range.

7. The method for selecting a silicon carbide varistor for generator field suppression according to claim 6, characterized in that: The performing a secondary screening of the first target valve plates according to the area of the region includes: sorting each first target valve plate for which the area Sn of the region is calculated by absolute value integration in ascending order of the area Sn of the region, and sequentially screening out the required number of valve plates to form the target combination.

8. A method for selecting a silicon carbide varistor for generator field suppression, characterized in that, including: a target data acquisition module for acquiring reference voltage data to obtain the current - reference voltage relationship curve and inputting the current and corresponding voltage data of each silicon carbide valve plate within the working range to obtain the current - voltage characteristic curve; a screening module for comparing the current - voltage characteristic curve of the silicon carbide valve plates with the current - reference voltage relationship curve and screening out the valve plates with a deviation less than ΔU; a result acquisition module for sorting the area Sn of each valve plate calculated in ascending order and screening out the required number of valve plates to form the target combination.

9. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method described in any one of claims 1 to 7.

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

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