Steady-state setting determination method, device, equipment and medium for AC filter

Abstract

The present application relates to a method, apparatus, device, and medium for determining steady-state setting values of AC filters. The method includes: First, according to the dimensional value of frequency offset, the dimensional value of detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system, determine the filter impedance of the AC-DC power transmission system; Second, divide the system impedance of the AC-DC power transmission system into regions, and scan the region boundaries of each divided impedance region to determine the system impedance of each impedance region; Furthermore, according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region, determine the steady-state setting values of the AC filter. In the present application, by simply scanning the region boundaries of each impedance region, the system impedance of each impedance region can be determined, improving the efficiency of calculating the system impedance. Furthermore, the calculation efficiency of determining the steady-state setting values of the AC filter is improved.

Description

Technical Field

[0001] The present application relates to the technical field of high-voltage power transmission, and particularly to a method, device, equipment and medium for determining the steady-state setting value of an AC filter. Background Art

[0002] With the development of high-voltage AC / DC power transmission technology, the harmonic problem in the AC / DC power transmission system is very prominent. The AC filter can filter out the harmonic on the AC side and compensate the reactive power, so it is widely used in the AC / DC power transmission system. In practical applications, the components in the AC filter need to meet certain steady-state stress requirements before they can be connected to the AC / DC power transmission system. Therefore, it is necessary to calculate the steady-state current stress and steady-state voltage stress corresponding to the components in the AC filter, that is, to calculate the steady-state setting value of the AC filter.

[0003] In the process of calculating the steady-state setting value of the AC filter, it is necessary to calculate the system impedance value of the AC / DC power transmission system. At present, the process of calculating the system impedance value is relatively cumbersome and the calculation amount is large, resulting in low efficiency in the process of calculating the steady-state setting value of the AC filter.

[0004] Therefore, how to improve the calculation efficiency of determining the steady-state setting value of the AC filter is a technical problem that needs to be solved urgently at present. Summary of the Invention

[0005] Based on this, in view of the above technical problems, it is necessary to provide a method, device, computer equipment, computer-readable storage medium and computer program product for determining the steady-state setting value of an AC filter, which can efficiently determine the steady-state setting value of the AC filter.

[0006] In a first aspect, the present application provides a method for determining the steady-state setting value of an AC filter. The method includes:

[0007] Determine the filter impedance of the AC / DC power transmission system according to the dimension value of the frequency deviation, the dimension value of the detuning factor and the configuration parameters of the AC filter in the AC / DC power transmission system;

[0008] Divide the system impedance of the AC / DC power transmission system into regions, and scan the region boundaries of each divided impedance region to determine the system impedance of each impedance region;

[0009] Determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance and the system impedance of each impedance region.

[0010] In one of the embodiments, scanning the region boundaries of each divided impedance region to determine the system impedance of each impedance region includes:

[0011] According to the preset scanning step, system parameter thresholds, and the dimensional values of frequency offset, detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system, scan the regional boundaries of each divided impedance region to determine the system impedance of each impedance region; wherein, the system parameter thresholds include: frequency dimension threshold, detuning dimension threshold, frequency threshold, load threshold, and operating condition threshold.

[0012] In one embodiment, scanning the regional boundaries of each divided impedance region to determine the system impedance of each impedance region includes:

[0013] Scan the regional boundaries of each divided impedance region to determine the candidate impedance of each impedance region;

[0014] According to the candidate impedance of each impedance region and the filter impedance, determine the alternative combined impedance of each impedance region;

[0015] According to the power supply type of the AC-DC power transmission system and the alternative combined impedance of each impedance region, determine the system impedance of each impedance region from the candidate impedance of each impedance region.

[0016] In one embodiment, according to the power supply type of the AC-DC power transmission system and the combined impedance of each impedance region, determining the system impedance of each impedance region from the candidate impedance of each impedance region includes:

[0017] If the power supply type of the AC-DC power transmission system is a converter harmonic current source, then use the candidate impedance corresponding to the maximum combined impedance of each impedance region as the system impedance of each impedance region;

[0018] If the power supply type of the AC-DC power transmission system is a background harmonic voltage source, then use the candidate impedance corresponding to the minimum combined impedance of each impedance region as the system impedance of each impedance region.

[0019] In one embodiment, according to the preset scanning step, system parameter thresholds, and the dimensional values of frequency offset, detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system, scan the regional boundaries of each divided impedance region to determine the system impedance of each impedance region includes:

[0020] For each impedance region, perform initialization processing on the dimensional values of frequency offset, detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system to obtain initialization parameters;

[0021] According to the scanning step and the initialization parameters, scan the regional boundaries of the divided impedance region to obtain the current impedance of the impedance region;

[0022] Determine the real-time combined impedance of the impedance region according to the current impedance of the impedance region and the filter impedance;

[0023] Determine whether the end condition is satisfied according to the relationship between the real-time combined impedance of the impedance region and the preset impedance threshold, and the relationship between the initialization parameters and the system parameter threshold;

[0024] If so, use the candidate impedance of the impedance region as the system impedance of the impedance region;

[0025] If not, update the initialization parameters, or update the initialization parameters and the preset impedance threshold, and then return to execute the operation of scanning the regional boundary of the divided impedance region according to the scanning step and the initialization parameters to obtain the current impedance of the impedance region.

[0026] In one embodiment, determining the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region includes:

[0027] Determine the total harmonic current flowing through the AC filter according to the power supply type of the AC-DC power transmission system, the filter impedance, and the system impedance of each impedance region;

[0028] Determine the sub-harmonic current of each component flowing through the AC filter according to the structural parameters and component parameters in the configuration parameters of the AC filter and the total harmonic current;

[0029] Determine the steady-state setting value of the AC filter according to the sub-harmonic current of each component flowing through the AC filter.

[0030] In a second aspect, the present application also provides a device for determining the steady-state setting value of an AC filter. The device includes:

[0031] The first determination module is configured to determine the filter impedance of the AC-DC power transmission system according to the dimension value of the frequency offset, the dimension value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system;

[0032] The second determination module is configured to divide the system impedance of the AC-DC power transmission system into regions, and scan the regional boundaries of the divided impedance regions to determine the system impedance of each impedance region;

[0033] The third determination module is configured to determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0034] In a third aspect, the present application also provides a computer device. The computer device includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0035] Determine the filter impedance of the AC-DC power transmission system according to the dimensional value of the frequency offset, the dimensional value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system;

[0036] Divide the system impedance of the AC-DC power transmission system into regions, and scan the regional boundaries of each divided impedance region to determine the system impedance of each impedance region;

[0037] Determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0038] In a fourth aspect, the present application also provides a computer-readable storage medium. On this computer-readable storage medium, a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0039] Determine the filter impedance of the AC-DC power transmission system according to the dimensional value of the frequency offset, the dimensional value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system;

[0040] Divide the system impedance of the AC-DC power transmission system into regions, and scan the regional boundaries of each divided impedance region to determine the system impedance of each impedance region;

[0041] Determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0042] In a fifth aspect, the present application also provides a computer program product. This computer program product includes a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0043] Determine the filter impedance of the AC-DC power transmission system according to the dimensional value of the frequency offset, the dimensional value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system;

[0044] Divide the system impedance of the AC-DC power transmission system into regions, and scan the regional boundaries of each divided impedance region to determine the system impedance of each impedance region;

[0045] Determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0046] The method, device, computer equipment, storage medium, and computer program product for determining the steady-state setting value of the above AC filter. First, according to the dimensional value of the frequency deviation, the dimensional value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system, determine the filter impedance of the AC-DC power transmission system; secondly, divide the system impedance of the AC-DC power transmission system into regions, and scan the regional boundaries of each divided impedance region to determine the system impedance of each impedance region; furthermore, according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region, determine the steady-state setting value of the AC filter. In this application, by scanning the regional boundaries of each impedance region to determine the system impedance of each impedance region, compared with calculating the system impedance of each point in the entire impedance region in the prior art, the efficiency of calculating the system impedance is improved, and furthermore, the calculation efficiency of determining the steady-state setting value of the AC filter is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 FIG. is an application environment diagram of a method for determining the steady-state setting value of an AC filter in an embodiment;

[0048] Figure 2 FIG. is a flowchart of a method for determining the steady-state setting value of an AC filter in an embodiment;

[0049] Figure 3 FIG. is a flowchart of a method for determining the system impedance value in an embodiment;

[0050] Figure 4 FIG. is a flowchart of a method for determining the system impedance value in another embodiment;

[0051] Figure 5A - Figure 5B FIG. is a schematic diagram of the process of determining the system impedance value in an embodiment;

[0052] Figure 6 FIG. is a flowchart of a method for determining the steady-state setting value of an AC filter in another embodiment;

[0053] Figure 7 FIG. is a structural block diagram of a device for determining the steady-state setting value of an AC filter in an embodiment;

[0054] Figure 8 FIG. is a structural block diagram of a second determination module in an embodiment;

[0055] Figure 9 FIG. is a structural block diagram of a third determination unit in an embodiment;

[0056] Figure 10 FIG. is a structural block diagram of a second determination module in another embodiment;

[0057] Figure 11 It is a structural block diagram of a third determination module in an embodiment;

[0058] Figure 12 It is an internal structure diagram of a computer device in an embodiment. Detailed implementation manners

[0059] In order to make the objectives, technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0060] The steady-state setting value determination method for an AC filter provided by an embodiment of the present application can be applied to an application environment as Figure 1 shown. In an embodiment, a computer device is provided. The computer device can be a server, and its internal structure diagram can be as Figure 1 shown. The computer device includes a processor, a memory, and a network interface 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, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store the steady-state setting value data of the AC filter. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, it implements a steady-state setting value determination method for an AC filter.

[0061] In an embodiment, as Figure 2 shown, a steady-state setting value determination method for an AC filter is provided. The method includes the following steps:

[0062] S201, determine the filter impedance of the AC-DC power transmission system according to the dimension value of the frequency deviation, the dimension value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system.

[0063] Among them, the AC-DC power transmission system refers to a system that transmits electric energy in the form of AC or DC.

[0064] The frequency deviation refers to the amplitude of the fundamental frequency deviation from the rated frequency in the AC-DC power transmission system. Among them, the deviation range f of the fundamental frequency ∈ [f min , f max , where the fundamental frequency is 50 Hz, and the frequency deviation of the AC-DC power transmission system shall not exceed ±0.5 Hz. That is, f min is -0.5 Hz, and f max is +0.5 Hz.

[0065] The dimensional value of the frequency offset refers to the number of dimensions of the frequency offset for calculating the filter impedance at different harmonic frequencies. The corresponding range p of the dimensional value of the frequency offset is p ∈ [1, f num , where f num is the number of dimensions corresponding to the frequency offset when the harmonic frequency is n. In practical applications, based on the set frequency scanning step f step , the number of dimensions of the frequency offset corresponding to each harmonic frequency can be determined using formula (1), and the dimensional value of the frequency offset can be obtained by summing the number of dimensions of the frequency offset corresponding to each harmonic frequency using formula (2).

[0066] f num (n) = 1 + (f max - f min ) * n / f step (1)

[0067]

[0068] where n is the harmonic frequency, and the value range of n is n ∈ [1, 2, …, 49, 50], [f min , f max is the offset range corresponding to the harmonic frequency of 1, f max is the maximum frequency offset value corresponding to the harmonic frequency of 1, and f min is the minimum frequency offset value corresponding to the harmonic frequency of 1.

[0069] The detuning factor refers to the influencing factor of external factors on the capacitor parameters of the filter. The corresponding dimensional range q of the detuning factor is q ∈ [1, 3]. When q takes 3, it corresponds to three dimensions: the maximum negative deviation value (Du_min), 0, and the maximum positive deviation value (Du_max). That is to say, the dimensional value of the detuning factor can be 1, 2, or 3.

[0070] The AC filter is a filter circuit composed of capacitors, inductors, resistors, etc. The AC filter can filter out power supply signals greater than a specific frequency in the power line.

[0071] The configuration parameters of the AC filter can include the filter structure, filter element parameters, and the number of filters with the same structure and parameters, etc.

[0072] In this embodiment, the impedance of each AC filter can be determined according to the dimensional value corresponding to the frequency offset, the dimensional value corresponding to the detuning factor, and the configuration parameters corresponding to the AC filter, and the impedance of the AC filters is summed to obtain the filter impedance of the AC-DC power transmission system.

[0073] In an alternative embodiment, to improve the efficiency of calculating the impedance of AC filters, the AC filters can be classified first according to the configuration parameters corresponding to each AC filter, in accordance with the consistency of structure and parameters, that is, the AC filters with the same structure and parameters are grouped into one category, and the quantity corresponding to each category of AC filters is determined. According to the dimensions corresponding to frequency deviation and detuning factors, combined with the configuration parameters of each category of AC filters, the impedance corresponding to this category of AC filters is determined. Multiply the impedance of each category of AC filters by its corresponding quantity, and then sum them up to obtain the impedance of the AC filters in the AC-DC power transmission system.

[0074] In another alternative embodiment, to accurately determine the impedance of the filters in the AC-DC power transmission system, considering the influence of different operating conditions and different load levels on the impedance of AC filters, the impedance of AC filters corresponding to different harmonic frequencies can be determined according to the dimension values corresponding to frequency deviation, the dimension values corresponding to detuning factors, the configuration parameters corresponding to AC filters, as well as different operating conditions and different load levels.

[0075] S202, divide the system impedance of the AC-DC power transmission system into regions, and scan the region boundaries of each divided impedance region to determine the system impedance of each impedance region.

[0076] The system impedance refers to the impedance presented when looking from the power supply access point towards the power supply side, that is, in an AC power transmission system, other impedance values except the filter impedance. Specifically, the system impedance includes the impedance exerted by resistance, inductance, and capacitance on AC and DC power.

[0077] In this embodiment, the system impedance in the AC power transmission system can be divided according to certain rules, and the region enclosed by each group of impedances after division is used as an impedance region. Among them, this region can be a regular geometric image such as a straight line, a circle, a sector, etc., or an irregular image composed of arbitrary lines.

[0078] In an alternative embodiment, since the system impedance regions corresponding to harmonics of different harmonic frequencies are different, the system impedance of the AC-DC power transmission system can be divided into multiple impedance regions according to the harmonic frequencies. To improve the efficiency of calculating the system impedance, only the boundaries of each divided impedance region need to be scanned to obtain the system impedance on the boundaries of each impedance region as the system impedance of each impedance region.

[0079] In practical applications, for the system impedance on the boundary of each divided impedance region, at least one of the scanning methods of angle scanning, resistance scanning, and reactance scanning can be used to obtain the system impedance on the boundary of each impedance region. For example, for the system impedance on the arc boundary with the origin as the center of the circle, the arc boundary can be scanned based on a preset scanning step size by means of angle scanning to determine the system impedance on the arc boundary. For the system impedance on the straight-line boundary passing through the coordinate origin, the resistance value scanning or reactance value scanning method can be adopted to scan the straight-line boundary based on a preset scanning step size to determine the system impedance on the straight-line boundary.

[0080] S203. Determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0081] In this embodiment, after determining the filter impedance and the system impedance of each impedance region, the current flowing through the filter element can be determined according to the series-parallel relationship between the filter impedance and the system impedance of each impedance region, as well as the filter structure, filter element parameters, and the number of filters with the same structure and parameters of the AC filter. Then, the steady-state setting value of the AC filter can be determined according to the current of each filter element and the impedance of each filter element.

[0082] In an alternative embodiment, first, the total harmonic current flowing through the AC filter can be determined according to the power supply type of the AC-DC power transmission system, the filter impedance, and the AC system impedance used for steady-state setting value calculation. Second, the sub-harmonic current flowing through each element of the AC filter can be determined according to the structural parameters and element parameters in the configuration parameters of the AC filter and the total harmonic current. Then, the steady-state setting value of the AC filter can be determined according to the sub-harmonic current flowing through each element of the AC filter.

[0083] In this embodiment, the power supply types of the AC-DC power transmission system include the current source of the converter harmonic current and the background harmonic voltage. First, the harmonic current generated by the current source of the converter harmonic current or the voltage source of the background harmonic voltage can be split according to the series-parallel relationship between the AC filter and the AC system impedance to determine the total harmonic current flowing through the AC filter. Specifically, when a converter harmonic current source is connected to the AC-DC power transmission system, the impedance of the AC filter and the impedance of the AC system are in a parallel relationship. According to the parallel relationship between the impedance of the AC filter and the impedance of the AC system, the current I1 flowing through the impedance of the AC filter can be determined. When the background harmonic voltage is connected to the AC-DC power transmission system, the impedance of the AC filter and the impedance of the AC system are in a series relationship. According to the series relationship between the impedance of the AC filter and the impedance of the AC system, the current I2 flowing through the impedance of the AC filter can be determined. Then, by combining the current I1 and the current I2 flowing through the impedance of the AC filter, the total harmonic current flowing through the AC filter can be obtained.

[0084] Secondly, the total harmonic current flowing through the filter is split to determine the harmonic current flowing through each type of filter branch. According to the quantity corresponding to each type of filter, the harmonic current flowing through each type of filter branch is split to determine the harmonic current corresponding to a single filter. Then, according to the series-parallel relationship of the components in a single filter, the harmonic current corresponding to a single filter is split to calculate the harmonic current flowing through each component of the filter.

[0085] In practical applications, based on the harmonic current flowing through the AC filter components caused by the current source of the converter harmonic current and the harmonic current flowing through the AC filter components caused by the background harmonic voltage, the following formula (3) can be used to calculate the harmonic current In generated on the AC filter components at each harmonic frequency.

[0086]

[0087] Among them, is the harmonic current flowing through the AC filter components caused by the harmonic current of the converter; is the harmonic current generated by the background harmonic voltage on the AC filter components;

[0088] k is a preset parameter value. The value of k can be determined according to different harmonic frequencies. Exemplarily, the corresponding relationship between the harmonic frequency and k is shown in Table 1 below.

[0089] Table 1 Corresponding relationship between harmonic frequency and preset parameter value

[0090] Harmonic frequency 3 5 7 9 > 9 and all even harmonics k value 1.6 1.28 0.72 0 0

[0091] After calculating the harmonic currents generated by each frequency on the AC filter components, based on the harmonic currents generated on the AC filter components and the impedance values of the AC filter components, the steady-state current stress on the AC filter components can be determined using the following formula (4), and the steady-state voltage stress on the AC filter components can be determined using the following formula (5).

[0092]

[0093]

[0094] Among them, I nx is the harmonic current generated by each harmonic frequency on the AC filter component, I x is the steady-state current stress on the AC filter component, Z nx is the impedance value of the AC filter component, n is the harmonic frequency, U x is the steady-state voltage stress on the AC filter component, n is the harmonic frequency, and the value range of n is n ∈ [1, 2, …, 49, 50].

[0095] In the embodiments of the present application, first, according to the dimensional values of frequency offset, detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system, the filter impedance of the AC-DC power transmission system is determined; second, the system impedance of the AC-DC power transmission system is divided into regions, and the regional boundaries of each divided impedance region are scanned to determine the system impedance of each impedance region; furthermore, according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region, the steady-state setting value of the AC filter is determined. In the present application, by scanning the regional boundaries of each impedance region to determine the system impedance of each impedance region, compared with calculating the system impedance of each point in the entire impedance region in the prior art, the efficiency of calculating the system impedance is improved, and furthermore, the calculation efficiency of determining the steady-state setting value of the AC filter is improved.

[0096] Based on the above embodiments, in order to accurately determine the system impedance of each impedance region, the present application provides a method for determining the system impedance value, as Figure 3 shown, and the method includes the following steps:

[0097] S301, scan the regional boundaries of each divided impedance region to determine the candidate impedance of each impedance region.

[0098] The candidate impedance refers to the impedance corresponding to each boundary point on the boundaries of each impedance region.

[0099] Specifically, after dividing each impedance region, for each impedance region, scanning can be performed on its boundary, that is, scanning each boundary point on the boundary to obtain the impedance of each boundary point on the boundary of the impedance region, and using it as a candidate impedance for the impedance region.

[0100] S302. Determine the alternative combined impedance of each impedance region according to the candidate impedance of each impedance region and the filter impedance.

[0101] In this embodiment, when a converter harmonic current source is connected to the AC-DC power transmission system, the AC filter impedance and the AC system impedance are in a parallel relationship. According to the parallel relationship between the AC filter impedance and the AC system impedance, the following formula (6) can be used to determine the alternative combined impedance of each impedance region.

[0102]

[0103] Among them, Z m is the alternative combined impedance of each impedance region when the AC filter impedance and the AC system impedance are in a parallel relationship. Z f is the AC filter impedance, and Z s is the AC system impedance.

[0104] When a background harmonic voltage is connected to the AC-DC power transmission system, the AC filter impedance and the AC system impedance are in a series relationship. According to the series relationship between the AC filter impedance and the AC system impedance, formula (7) can be used to calculate the alternative combined impedance of each impedance region.

[0105] |Z n | = |Z f + Z s | (7)

[0106] Among them, |Z n | is the alternative combined impedance of each impedance region when the AC filter impedance and the AC system impedance are in a series relationship. Z f is the AC filter impedance, and Z s is the AC system impedance.

[0107] It should be noted that in this embodiment, for the candidate impedance corresponding to each boundary point on the boundary of each impedance region, there is a corresponding alternative combined impedance, that is, for the boundary of an impedance region, there are multiple alternative combined impedances.

[0108] S303. Determine the system impedance of each impedance region from the candidate impedances of each impedance region according to the power supply type of the AC-DC power transmission system and the alternative combined impedance of each impedance region.

[0109] The power supply types of the AC-DC power transmission system include converter harmonic current sources and background harmonic voltages. In this embodiment, when determining the power supply types of the AC-DC power transmission system, the alternative combined impedances of each impedance region can be determined according to the series-parallel relationship between the AC filter impedance and the AC system impedance, and the system impedance of each impedance region can be determined based on the alternative combined impedances.

[0110] In one embodiment, if the power supply type of the AC-DC power transmission system is a converter harmonic current source, the candidate impedance corresponding to the maximum combined impedance of each impedance region is used as the system impedance of each impedance region; if the power supply type of the AC-DC power transmission system is a background harmonic voltage source, the candidate impedance corresponding to the minimum combined impedance of each impedance region is used as the system impedance of each impedance region.

[0111] Specifically, when a converter harmonic current source is connected to the AC-DC power transmission system, the AC filter impedance and the AC system impedance are in a parallel relationship. According to the above formula (6), the candidate impedance corresponding to the maximum combined impedance of each impedance region can be determined, and this candidate impedance is used as the system impedance of this impedance region. When a background harmonic voltage is connected to the AC-DC power transmission system, the AC filter impedance and the AC system impedance are in a series relationship. According to the above formula (7), the candidate impedance corresponding to the minimum combined impedance of each impedance region can be determined, and this candidate impedance is used as the system impedance of this impedance region.

[0112] In this embodiment, according to the power supply type in the AC-DC power transmission system, when the AC filter impedance and the AC system resistance are in a parallel relationship, the candidate impedance corresponding to the maximum combined impedance of each impedance region can be used as the system impedance. When the AC filter impedance and the AC system impedance are in a series relationship, the candidate impedance corresponding to the minimum combined impedance of each impedance region can be used as the system impedance. In this way, the system impedance of each impedance region can be accurately determined.

[0113] Based on the above embodiment, in order to accurately determine the system impedance of each impedance region, the present application provides another method for determining the system impedance value. This method includes scanning the regional boundaries of each impedance region after division according to a preset scanning step, system parameter thresholds, and the dimensional values of frequency offset, detuning factor, harmonic frequency, load level, and operating conditions in the AC-DC power transmission system to determine the system impedance of each impedance region; where the system parameter thresholds include: frequency dimension threshold, detuning dimension threshold, frequency threshold, load threshold, and operating condition threshold.

[0114] Among them, the preset scanning step refers to the scanning step set when scanning the boundary of the impedance region. The load level refers to the amount of load connected in the AC-DC power transmission system, and the load threshold is the maximum load level number R that the AC-DC power transmission system can bear. Specifically, the value range corresponding to this load level is r ∈ [1, R].

[0115] The operating condition refers to the working state of the equipment connected in the AC-DC power transmission system under certain conditions. The condition threshold Loc corresponding to the number of operating conditions refers to the maximum number of operating conditions that the AC-DC power transmission system can bear. The value range of the number of operating conditions connected in the AC-DC power transmission system is l ∈ [1, Loc].

[0116] The frequency dimension threshold refers to the dimension value f of the frequency offset corresponding to the harmonic frequency n. num 。

[0117] The detuning dimension threshold is the maximum dimension value corresponding to the detuning factor.

[0118] The frequency threshold is the frequency offset range f ∈ [nf min ,nf max 。

[0119] In the process of determining the system impedance by scanning in this embodiment, based on the five dimensions of the dimension corresponding to the detuning factor, frequency offset, harmonic frequency, load level, and operating condition, combined with the preset scanning step and the system parameter thresholds corresponding to these five dimensions, the regional boundaries of each impedance region are scanned to determine the system impedance of each impedance region, improving the accuracy of determining the system impedance of each impedance region.

[0120] On the basis of the above embodiment, as Figure 4 shown, this embodiment gives an optional method for scanning the regional boundaries of each divided impedance region according to the preset scanning step, system parameter thresholds, and the dimension value of the frequency offset, the dimension value of the detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system to determine the system impedance of each impedance region, including the following steps:

[0121] S401. For each impedance region, initialize the dimension value of the frequency offset, the dimension value of the detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system to obtain initialization parameters.

[0122] Exemplarily, in this embodiment Figure 5A the method for obtaining the system impedance Zs1 when the filter impedance and the system impedance are in a parallel relationship, Figure 5B the method for obtaining the system impedance Zs2 when the filter impedance and the system impedance are in a series relationship.

[0123] S501 in 5A and S521 in 5B correspond to the process of initializing the preset impedance threshold, the dimensional value p of the frequency offset, the dimensional value q of the detuning factor, the harmonic frequency n, the load level r, and the operating condition l, that is, initializing the value of the preset impedance threshold Z1 in the parallel relationship to a smaller value, such as 0, and initializing the value of the preset impedance threshold Z2 in the series relationship to a larger value, such as 10. 10 The dimensional value p of the frequency offset, the dimensional value q of the detuning factor, the harmonic frequency n, the load level r, and the operating condition l are all initialized to 0.

[0124] S402. According to the scanning step and the initialization parameters, scan the region boundaries of the divided impedance regions to obtain the current impedance of the impedance regions.

[0125] Taking 5A as an example for description, in S502 - S506, p, q, n, r, and l can be assigned values, that is, perform the operation of adding 1 to p, q, n, r, and l. In S507, scan the impedance boundary region to obtain the current impedance Z of the impedance region. S1 In 5B, for the description in S522 - S527, refer to S502 - S507 in 5A, which will not be elaborated here.

[0126] S403. According to the current impedance of the impedance region and the filter impedance, determine the real-time combined impedance of the impedance region.

[0127] For example, Figure 5A in S508 shown as follows, the filter impedance and the system impedance are in a parallel relationship. According to the current impedance and the filter impedance, the real-time combined impedance of the impedance region can be obtained using formula (8).

[0128]

[0129] where f m (l, r, n, p, q) is the real-time combined impedance corresponding to the case where the filter impedance and the system impedance are in a series relationship, Z f (l, r, n, p, q) is the filter impedance, and Z s1 is the current impedance corresponding to the case where the filter impedance and the system impedance are in a parallel relationship.

[0130] Similarly, in S528 shown in Figure 5(b), the filter impedance and the system impedance are in a series relationship. According to the current impedance and the filter impedance, the real-time combined impedance of the impedance region can be obtained using formula (9);

[0131] Z n (l, r, n, p, q) = |Z f (l, r, n, p, q) + Zs2 | (9)

[0132] Among them, Z n (l, r, n, p, q) is the real-time combined impedance corresponding when the filter impedance and the system impedance are in a series relationship, and Z f (l, r, n, p, q) is the filter impedance, and Z s2 is the current impedance corresponding when the filter impedance and the system impedance are in a series relationship.

[0133] S404. Determine whether the end condition is satisfied according to the relationship between the real-time combined impedance of the impedance region and the preset impedance threshold, and the relationship between the initialization parameters and the system parameter threshold. If so, execute S405; if not, execute S406.

[0134] In S509 - S519 as shown in Figure 5A , S509 judges the relationship between the preset impedance threshold Z1 and f m (l, r, n, p, q), and in S511 - S519, respectively judge the relationships between p, q, n, r, l and their respective corresponding parameter thresholds, and determine whether the end condition is satisfied currently according to the judgment results.

[0135] In S529 - S539 as shown in Figure 5B , S529 judges the relationship between the preset impedance threshold Z2 and Z n (l, r, n, p, q), and in S531 - S539, respectively judge the relationships between p, q, n, r, l and their respective corresponding parameter thresholds, and determine whether the end condition is satisfied currently according to the judgment results.

[0136] S405. Take the candidate impedance of the impedance region as the system impedance of the impedance region.

[0137] In Figure 5A , in S520, if the preset impedance threshold Z1 is less than f m (l, r, n, p, q), p is greater than f num , q is greater than 3, n is greater than 50, r is greater than R, and l is greater than Loc, then it is determined that the end condition is satisfied. At this time, execute the operation in S520 to output Z S1 , that is, take the system impedance value corresponding to the boundary point of this scan as the Z corresponding to the maximum real-time combined impedance when the AC filter impedance and the AC system resistance are in a parallel relationship S1 , as the system impedance.

[0138] In Figure 5B , in S529, if the preset impedance threshold Z2 is greater than Z n (l, r, n, p, q), p is greater than fnum If q > 3, n > 50, r > R, and l > Loc, then it is determined that the end condition is satisfied. At this time, in S540, Z is output S2 That is, the operation of taking the system impedance value Z corresponding to the boundary point scanned this time S2 When the AC filter impedance and the AC system resistance are in a series relationship, take the Z corresponding to the minimum real-time combined impedance S2 As the system impedance.

[0139] S406: Update the initialization parameters, or update the initialization parameters and the preset impedance threshold, and then return to execute S402.

[0140] Specifically, after S509 in 5A, if the relationship between the preset impedance threshold Z1 and f m (l, r, n, p, q) satisfies the preset condition Z1 < f m (l, r, n, p, q), then execute S510, Z1 = f m (l, r, n, p, q). After executing S510, execute S511; if the preset condition is not satisfied, directly execute S511.

[0141] S511: Judge whether the value p of the current frequency deviation dimension is greater than the frequency dimension threshold f num If so, execute S512, p = 0, and after executing S512, execute S513. If not, return to execute S506.

[0142] S513: Judge whether the dimension range q corresponding to the detuning factor is greater than the detuning dimension threshold 3. If so, execute S514, q = 0, and after executing S514, execute S515; if not, return to execute S505.

[0143] S515: Judge whether the current frequency based on the harmonic frequency n is greater than the frequency threshold 50. If so, execute S516, n = 0, and after executing S516, execute S517; if not, return to execute S504.

[0144] S517: Judge whether the current load level number r is greater than the load threshold R. If so, execute S518, r = 0, and after executing S518, execute S519; if not, return to execute S503.

[0145] S519: Judge whether the operating condition l is greater than the condition threshold. If it is Loc, then execute S520 to output the system impedance Zs1; if not, return to execute S502.

[0146] In such as Figure 5BIn [the description of the output system impedance Zs2 in S529 - S540, refer to S509 - S520 in 5A, which will not be elaborated here.

[0147] In the process of determining the system impedance by scanning in this embodiment, based on the five dimensions of the detuning factor - corresponding dimension, frequency offset, harmonic frequency, load level, and operating condition, combined with the preset scanning step and the system parameter thresholds corresponding to these five dimensions, scan the regional boundaries of each impedance region. When the AC filter impedance and the AC system impedance are in a parallel relationship, the system impedance corresponding to the maximum real - time combined impedance of each impedance region can be determined as the output system impedance Z of this impedance region. S1 When the AC filter impedance and the AC system impedance are in a series relationship, the system impedance corresponding to the minimum real - time combined impedance of each impedance region can be determined as the output system impedance Z of this impedance region. S2 .

[0148] On the basis of the above - mentioned embodiment, in order to understand the determination of the system impedance of each impedance region, the present application provides another method for determining the steady - state setting value of the AC filter, as Figure 6 shown. This method includes:

[0149] S601, Determine the filter impedance of the AC - DC transmission system according to the dimension value of the frequency offset, the dimension value of the detuning factor, and the configuration parameters of the AC filter in the AC - DC transmission system.

[0150] S602, Divide the system impedance of the AC - DC transmission system into regions.

[0151] S603, For each impedance region, perform initialization processing on the dimension value of the frequency offset, the dimension value of the detuning factor, the harmonic frequency, the load level, and the operating condition in the AC - DC transmission system to obtain initialization parameters.

[0152] S604, According to the scanning step and the initialization parameters, scan the regional boundaries of the divided impedance regions to obtain the current impedance of the impedance regions.

[0153] S605, Determine the real - time combined impedance of the impedance region according to the current impedance of the impedance region and the filter impedance.

[0154] S606, According to the relationship between the real - time combined impedance of the impedance region and the preset impedance threshold, and the relationship between the initialization parameters and the system parameter threshold, determine whether the end condition is met. If so, execute S607; if not, execute S608.

[0155] S607, Use the candidate impedance of the impedance region as the system impedance of the impedance region.

[0156] S608, after updating the initialization parameters or after updating the initialization parameters and the preset impedance threshold, return to execute S604.

[0157] S609, determine the total harmonic current flowing through the AC filter according to the power supply type of the AC-DC transmission system, the filter impedance, and the system impedance of each impedance region.

[0158] S610, determine the sub-harmonic current of each component flowing through the AC filter according to the structural parameters and component parameters in the configuration parameters of the AC filter and the total harmonic current.

[0159] S611, determine the steady-state setting value of the AC filter according to the sub-harmonic current of each component flowing through the AC filter.

[0160] It should be understood that although the steps in the flowcharts involved in the above-described embodiments are sequentially shown according to the indication of the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-described embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least a part of other steps or steps or stages in other steps.

[0161] Based on the same inventive concept, an embodiment of the present application also provides a device for determining the steady-state setting value of an AC filter for implementing the method for determining the steady-state setting value of the AC filter involved above. The solution provided by this device to solve the problem is similar to the solution described in the above method. Therefore, the specific limitations in one or more embodiments of the device for determining the steady-state setting value of the AC filter provided below can refer to the limitations on the method for determining the steady-state setting value of the AC filter in the above text, and will not be repeated here.

[0162] In one embodiment, as Figure 7 shown, a device for determining the steady-state setting value of an AC filter is provided, including: a first determination module 10, a second determination module 20, and a third determination module 30, where:

[0163] The first determination module 10 is configured to determine the filter impedance of the AC-DC transmission system according to the dimension value of the frequency offset, the dimension value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC transmission system;

[0164] The second determination module 20 is configured to divide the system impedance of the AC-DC power transmission system, scan the regional boundaries of each divided impedance region, and determine the system impedance of each impedance region.

[0165] The third determination module 30 is configured to determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0166] In one embodiment, the above Figure 7 The second determination module 20 is specifically configured to:

[0167] Scan the regional boundaries of each divided impedance region according to a preset scanning step, system parameter thresholds, and the dimension values of frequency offset, detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system, and determine the system impedance of each impedance region; wherein, the system parameter thresholds include: frequency dimension threshold, detuning dimension threshold, frequency threshold, load threshold, and condition threshold.

[0168] In one embodiment, on the basis of the above Figure 7 As shown in Figure 8 The second determination module 20 in the above Figure 7 includes:

[0169] The first determination unit 101 is configured to scan the regional boundaries of each divided impedance region and determine the candidate impedance of each impedance region.

[0170] The second determination unit 102 is configured to determine the alternative combined impedance of each impedance region according to the candidate impedance of each impedance region and the filter impedance.

[0171] The third determination unit 103 is configured to determine the system impedance of each impedance region from the candidate impedances of each impedance region according to the power supply type of the AC-DC power transmission system and the alternative combined impedance of each impedance region.

[0172] In one embodiment, on the basis of at least one of the above Figure 7 or Figure 8 As shown in Figure 9 The third determination unit 103 in the above Figure 7 includes:

[0173] The first sub-unit 1031 is configured to, when the power supply type of the AC-DC power transmission system is a converter harmonic current source, use the candidate impedance corresponding to the maximum combined impedance of each impedance region as the system impedance of each impedance region.

[0174] The second sub-unit 1032 is configured to use the candidate impedance corresponding to the minimum combined impedance of each impedance region as the system impedance of each impedance region when the power supply type of the AC-DC power transmission system is a background harmonic voltage source.

[0175] In one embodiment, based on at least one of the above Figure 7 , Figure 8 , Figure 9 , as shown in Figure 10 , the second determination module 20 may further include:

[0176] The processing unit 104 is configured to perform initialization processing on the dimension value of frequency deviation, the dimension value of detuning factor, the harmonic frequency, the load level, and the operating condition in the AC-DC power transmission system for each impedance region to obtain initialization parameters;

[0177] The scanning unit 105 is configured to scan the region boundary of the divided impedance region according to the scanning step and the initialization parameters to obtain the current impedance of the impedance region;

[0178] The combining unit 106 is configured to determine the real-time combined impedance of the impedance region according to the current impedance of the impedance region and the filter impedance;

[0179] The judgment unit 107 is configured to determine whether the end condition is satisfied according to the relationship between the real-time combined impedance of the impedance region and the preset impedance threshold, and the relationship between the initialization parameters and the system parameter threshold. If so, the candidate impedance of the impedance region is used as the system impedance of the impedance region; if not, the initialization parameters are updated, or after updating the initialization parameters and the preset impedance threshold, return to execute the operation of scanning the region boundary of the divided impedance region according to the scanning step and the initialization parameters to obtain the candidate impedance of the impedance region.

[0180] In one embodiment, as shown in Figure 11 , the above Figure 7 The third determination module 30 includes:

[0181] The first current unit 301 is configured to determine the total harmonic current flowing through the AC filter according to the power supply type of the AC-DC power transmission system, the filter impedance, and the system impedance of each impedance region;

[0182] The second current unit 302 is configured to determine the sub-harmonic current of each component flowing through the AC filter according to the structural parameters and component parameters in the configuration parameters of the AC filter and the total harmonic current;

[0183] The third current unit 303 is configured to determine the steady-state setting value of the AC filter according to the sub-harmonic current of each component flowing through the AC filter.

[0184] The present application relates to a device for determining the steady-state setting value of an AC filter. The device includes: First, determine the filter impedance of the AC-DC power transmission system according to the dimensional value of the frequency offset, the dimensional value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system; Second, divide the system impedance of the AC-DC power transmission system into regions, and scan the region boundaries of each divided impedance region to determine the system impedance of each impedance region; Furthermore, determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region. In the present application, by scanning the region boundaries of each impedance region to determine the system impedance of each impedance region, compared with calculating the system impedance of each point in the entire impedance region in the prior art, the efficiency of calculating the system impedance is improved, and furthermore, the calculation efficiency of determining the steady-state setting value of the AC filter is improved.

[0185] Each module in the above device for determining the steady-state setting value of the AC filter can be implemented in whole or in part by software, hardware, and their combination. Each of the above modules can be embedded in the processor in the computer device in the form of hardware or be independent of it, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to each of the above modules.

[0186] In one embodiment, a computer device is provided. The computer device can be a terminal, and its internal structure diagram can be as Figure 12 shown. 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 achieved through WIFI, a mobile cellular network, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a method for determining the steady-state setting value of an AC filter.

[0187] Those skilled in the art can understand that Figure 12 the structure shown in

[0188] In one embodiment, a computer device is provided, including a memory and a processor. A computer program is stored in the memory. When the processor executes the computer program, the following steps are implemented:

[0189] Determine the filter impedance of the AC-DC power transmission system according to the dimensional value of the frequency offset, the dimensional value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system;

[0190] Divide the system impedance of the AC-DC power transmission system into regions, scan the regional boundaries of each divided impedance region, and determine the system impedance of each impedance region;

[0191] Determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0192] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0193] Determine the filter impedance of the AC-DC power transmission system according to the dimensional value of the frequency offset, the dimensional value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system;

[0194] Divide the system impedance of the AC-DC power transmission system into regions, scan the regional boundaries of each divided impedance region, and determine the system impedance of each impedance region;

[0195] Determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0196] In one embodiment, a computer program product is provided, including a computer program. When the computer program is executed by a processor, the following steps are implemented:

[0197] Determine the filter impedance of the AC-DC power transmission system according to the dimensional value of the frequency offset, the dimensional value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system;

[0198] Divide the system impedance of the AC-DC power transmission system into regions, scan the regional boundaries of each divided impedance region, and determine the system impedance of each impedance region;

[0199] Determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region.

[0200] It should be noted that the data involved in this application (including but not limited to the data for analysis, stored data, displayed data, etc.) are all information and data that have been fully authorized by all parties.

[0201] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The databases involved in the embodiments provided in this application can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the embodiments provided in this application can be general-purpose processors, central processors, graphics processors, digital signal processors, programmable logic devices, data processing logics based on quantum computing, etc., without limitation.

[0202] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0203] The above-described embodiments merely represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the patent scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the appended claims.

Claims

1. A method for determining the steady-state setting value of an AC filter, characterized in that The method includes: Determining the filter impedance of the AC-DC power transmission system according to the dimension value of the frequency deviation, the dimension value of the detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system; Dividing the system impedance of the AC-DC power transmission system into regions, and scanning the region boundaries of each divided impedance region to determine the system impedance of each impedance region; Determining the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region; Among them, the scanning of the region boundaries of each divided impedance region to determine the system impedance of each impedance region includes: Scanning the region boundaries of each divided impedance region according to a preset scanning step, system parameter thresholds, and the dimension value of the frequency deviation, the dimension value of the detuning factor, the harmonic frequency, the load level, and the operating condition in the AC-DC power transmission system to determine the system impedance of each impedance region; wherein, the system parameter thresholds include: a frequency dimension threshold, a detuning dimension threshold, a frequency threshold, a load threshold, and an operating condition threshold; Among them, the scanning of the region boundaries of each divided impedance region to determine the system impedance of each impedance region includes: Scanning the region boundaries of each divided impedance region to determine the candidate impedance of each impedance region; determining the alternative combined impedance of each impedance region according to the candidate impedance of each impedance region and the filter impedance; and determining the system impedance of each impedance region from the candidate impedance of each impedance region according to the power supply type of the AC-DC power transmission system and the alternative combined impedance of each impedance region; Among them, the determining the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region includes: Determining the total harmonic current flowing through the AC filter according to the power supply type of the AC-DC power transmission system, the filter impedance, and the system impedance of each impedance region; determining the sub-harmonic current of each component flowing through the AC filter according to the structural parameters and component parameters in the configuration parameters of the AC filter and the total harmonic current; and determining the steady-state setting value of the AC filter according to the sub-harmonic current of each component flowing through the AC filter.

2. The method according to claim 1, characterized in that Determining the system impedance of each impedance region from the candidate impedance of each impedance region according to the power supply type of the AC-DC power transmission system and the combined impedance of each impedance region includes: If the power supply type of the AC-DC power transmission system is a converter harmonic current source, taking the candidate impedance corresponding to the maximum combined impedance of each impedance region as the system impedance of each impedance region; If the power supply type of the AC-DC power transmission system is a background harmonic voltage source, taking the candidate impedance corresponding to the minimum combined impedance of each impedance region as the system impedance of each impedance region.

3. The method according to claim 1, characterized in that, Scanning the regional boundaries of each impedance region after division according to the preset scanning step, system parameter threshold, the dimensional value of frequency offset, the dimensional value of detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system to determine the system impedance of each impedance region, including: For each impedance region, perform initialization processing on the dimensional value of frequency offset, the dimensional value of detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system to obtain initialization parameters; According to the scanning step and the initialization parameters, scan the regional boundaries of the divided impedance region to obtain the current impedance of the impedance region; According to the current impedance of the impedance region and the filter impedance, determine the real-time combined impedance of the impedance region; According to the relationship between the real-time combined impedance of the impedance region and the preset impedance threshold, and the relationship between the initialization parameters and the system parameter threshold, determine whether the end condition is satisfied, If so, use the candidate impedance of the impedance region as the system impedance of the impedance region; If not, update the initialization parameters, or update the initialization parameters and the preset impedance threshold, and then return to execute the operation of scanning the regional boundaries of the divided impedance region according to the scanning step and the initialization parameters to obtain the current impedance of the impedance region.

4. The method according to claim 3, characterized in that The determining the real-time combined impedance of the impedance region according to the current impedance of the impedance region and the filter impedance includes: If the filter impedance and the system impedance are in a parallel relationship, according to the current impedance and the filter impedance, use the following formula to obtain the real-time combined impedance of the impedance region: ； Among them, is the real-time combined impedance corresponding to the case where the filter impedance and the system impedance are in a parallel relationship, is the filter impedance, is the current impedance corresponding to the case where the filter impedance and the system impedance are in a parallel relationship; If the filter impedance and the system impedance are in a series relationship, according to the current impedance and the filter impedance, use the following formula to obtain the real-time combined impedance of the impedance region: ； Among them, is the real-time combined impedance corresponding to the case where the filter impedance and the system impedance are in a series relationship, is the filter impedance, is the current impedance corresponding to the case where the filter impedance and the system impedance are in a series relationship; Where, l is the operating condition, r is the load level, n is the harmonic frequency, p is the dimensional value of frequency offset, and q is the dimensional value of detuning factor.

5. The method according to claim 4, characterized in that The determining whether the end condition is satisfied according to the relationship between the real-time combined impedance of the impedance region and the preset impedance threshold, and the relationship between the initialization parameters and the system parameter threshold includes: If the preset impedance threshold Z1 is less than and the initialization parameter is greater than the corresponding system parameter threshold, it is determined that the end condition is satisfied; or If the preset impedance threshold Z2 is greater than and the initialization parameter is greater than the corresponding system parameter threshold, it is determined that the end condition is satisfied.

6. The method according to any one of claims 1-5, characterized in that, The dimensional value of frequency offset is determined in the following manner: Based on the set frequency scanning step size , the number of dimensions of the frequency offset corresponding to each harmonic frequency is determined using the following formula; ； Use the following formula to sum the dimensional numbers of frequency offset corresponding to each harmonic frequency to obtain the dimensional value of frequency offset: ； Among them, n is the harmonic frequency, and the value range of n is , is the offset range corresponding to the harmonic frequency of 1, is the maximum frequency offset value corresponding to the harmonic frequency of 1, is the minimum frequency offset value corresponding to the harmonic frequency of 1.

7. A steady-state setting determination device for an AC filter, characterized in that The device includes: A first determination module, configured to determine the filter impedance of the AC-DC power transmission system according to the dimensional value of frequency offset, the dimensional value of detuning factor, and the configuration parameters of the AC filter in the AC-DC power transmission system; A second determination module, configured to perform regional division on the system impedance of the AC-DC power transmission system, and scan the regional boundaries of each impedance region after division to determine the system impedance of each impedance region; A third determination module, configured to determine the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region; Among them, scanning the regional boundaries of each divided impedance region to determine the system impedance of each impedance region includes: Scanning the regional boundaries of each divided impedance region according to a preset scanning step, system parameter thresholds, the dimensional value of frequency deviation, the dimensional value of detuning factor, harmonic frequency, load level, and operating condition in the AC-DC power transmission system to determine the system impedance of each impedance region; among them, the system parameter thresholds include: frequency dimensional threshold, detuning dimensional threshold, frequency threshold, load threshold, and condition threshold; Among them, scanning the regional boundaries of each divided impedance region to determine the system impedance of each impedance region includes: Scanning the regional boundaries of each divided impedance region to determine the candidate impedance of each impedance region; determining the alternative combined impedance of each impedance region according to the candidate impedance of each impedance region and the filter impedance; determining the system impedance of each impedance region from the candidate impedance of each impedance region according to the power supply type of the AC-DC power transmission system and the alternative combined impedance of each impedance region; Among them, determining the steady-state setting value of the AC filter according to the configuration parameters of the AC filter, the filter impedance, and the system impedance of each impedance region includes: Determining the total harmonic current flowing through the AC filter according to the power supply type of the AC-DC power transmission system, the filter impedance, and the system impedance of each impedance region; determining the sub-harmonic current of each component flowing through the AC filter according to the structural parameters and component parameters in the configuration parameters of the AC filter and the total harmonic current; determining the steady-state setting value of the AC filter according to the sub-harmonic current of each component flowing through the AC filter.

8. 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 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the method described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the method described in any one of claims 1 to 6.

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