A power transmission protection method, medium and system for wireless anti-interference converter station

Abstract

The present invention discloses a transmission protection method, medium and system for a wireless anti-interference converter station, including: collecting the voltage of the DC transmission line of the converter station at preset intervals, wherein the DC transmission line includes: a positive line and a negative line; using the voltage of the positive line and the voltage of the negative line to calculate the voltage variance of each line; if the voltage variance of the positive line or the negative line is greater than a first threshold, then calculating the first elastic coefficient and the second elastic coefficient of the current energy on both sides of each line of the positive line and the negative line respectively; according to the product of the absolute value of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line and the size relationship of the second threshold, determining the fault position of the DC transmission line of the converter station. The present invention is not affected by line distribution parameters and communication interference, is simple and reliable, and provides technical support for the safe and reliable operation of flexible systems.

Description

Technical Field

[0001] The present invention relates to the technical field of direct current transmission line protection of a converter station, and in particular to a transmission protection method, medium and system of a wireless anti-interference converter station. Background Art

[0002] At present, there are a large number of communication devices in DC converter stations, and these communication devices use different communication protocols and standards. Transmission lines often use overhead lines, which have a higher probability of failure than DC cable lines, and the fault current rises quickly. The modular multilevel converter (MMC) is expensive and fragile. If the fault line cannot be cut off in time, it will cause great damage to the DC equipment and even further undermine the safety of the power system. However, a large number of communication devices with different standards generate wireless interference, resulting in low reliability of fault detection schemes based on communication technology. In addition, there are very large distributed capacitance currents in the line, which will affect the speed of existing protection schemes. This delay may cause the AC side protection to take precedence over the DC side protection action, causing the converter station to exit operation, greatly expanding the scope of fault isolation and removal. In summary, the distributed capacitance current and communication interference problems of the line seriously affect the reliability of fault detection and protection. Summary of the invention

[0003] The embodiments of the present invention provide a power transmission protection method, medium and system for a wireless anti-interference converter station to solve the problem of low reliability caused by distributed capacitance current and communication interference in the prior art.

[0004] In a first aspect, a power transmission protection method for a wireless anti-interference converter station is provided, comprising:

[0005] The voltage of the DC transmission line of the converter station is collected at preset intervals, wherein the DC transmission line includes: a positive line and a negative line;

[0006] The voltage of the positive line and the voltage of the negative line are respectively used to calculate the voltage variance of the respective lines;

[0007] If the voltage variance of the positive line or the negative line is greater than a first threshold, respectively calculating a first elastic coefficient and a second elastic coefficient of current energy on both sides of the positive line and the negative line;

[0008] The fault position of the DC transmission line of the converter station is determined according to the magnitude relationship between the product of the absolute values ​​of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line and a second threshold.

[0009] In a second aspect, a computer-readable storage medium is provided, on which computer program instructions are stored; when the computer program instructions are executed by a processor, the power transmission protection method of the wireless anti-interference converter station as described in the embodiment of the first aspect above is implemented.

[0010] In a third aspect, a power transmission protection system for a wireless anti-interference converter station is provided, comprising: a computer-readable storage medium as described in the above-mentioned embodiment of the second aspect.

[0011] In this way, according to the embodiment of the present invention, based on the frequency characteristics of the distributed capacitor current, the filtering characteristics of the current energy are used to filter out the distributed capacitor current, so that the fault detection and backup protection schemes are not affected by the line distribution parameters, such as transition resistance and line distributed capacitance, and the long delay problem of backup protection after the fault is detected is solved; the elastic coefficient is applied to the fault detection and protection of the power system, and the characteristic that the elastic coefficient only needs to process the data of the local end to transmit to the opposite end solves the problem that the current differential protection needs strict communication synchronization, and greatly reduces the communication burden; the current energy and the elastic coefficient are combined to construct a fault detection and fast backup protection scheme for the DC transmission line that is free from communication interference, so that the scheme is simple and reliable; the present invention provides technical support for the safe and reliable operation of the flexible system. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0013] Figure 1 is a flow chart of a power transmission protection method for a wireless anti-interference converter station according to Embodiment 1 of the present invention;

[0014] Figure 2 is a flow chart of a power transmission protection method for a wireless anti-interference converter station according to Embodiment 2 of the present invention;

[0015] Figure 3 is a flow chart of a power transmission protection method for a wireless anti-interference converter station according to Embodiment 3 of the present invention;

[0016] Figure 4 It is the equivalent circuit diagram of the converter station. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1

[0019] Embodiment 1 of the present invention discloses a transmission protection method for a wireless anti-interference converter station. The method is applicable to a case where a single fault occurs in a DC transmission line of a converter station during a detection period. Specifically, Figure 1 As shown, the method comprises the following steps:

[0020] Step S101: collecting the voltage of the DC transmission line of the converter station at preset time intervals.

[0021] The DC transmission line includes a positive line and a negative line. The preset time can be determined based on experience and actual conditions. Specifically, the voltage can be collected using corresponding equipment.

[0022] Step S102: using the voltage of the positive line and the voltage of the negative line respectively to calculate the voltage variance of each line.

[0023] Specifically, whether it is a positive line or a negative line, the calculation formula for voltage variance is as follows:

[0024]

[0025] Where D(U) represents the voltage variance, x i represents the collected voltage of the corresponding line (positive line or negative line), x represents the average value of the collected voltage of the corresponding line (positive line or negative line), and n represents the number of collected voltages of the corresponding line (positive line or negative line).

[0026] Through this step, the voltage variance of the positive line or the voltage variance of the negative line can be obtained.

[0027] Step S103: if the voltage variance of the positive line or the negative line is greater than the first threshold, then respectively calculating the first elastic coefficient and the second elastic coefficient of the current energy on both sides of the positive line and the negative line.

[0028] As Figure 4Taking the equivalent circuit shown as an example, the absolute value of the pole current or the sudden change of the current is often used to construct the starting element in the longitudinal differential protection, and the protection is activated when the threshold is exceeded. However, the current starting element requires higher sensitivity. In the case of a single-pole high-resistance grounding fault, the current change is small, which may affect the rapidity of the current starting element. In addition, when the distributed capacitance of the DC transmission line is too large, the transient current at the moment of the fault may be affected by the distributed capacitance current, thereby reducing the sensitivity of the current starting element. Based on the above reasons, the embodiment of the present invention selects voltage variance as the starting element. The voltage variance represents the degree of deviation of the current. The greater the trend of voltage waveform change, the greater the voltage variance.

[0029] Specifically, D(U) set represents the first threshold, that is, as long as the voltage variance corresponding to one of the positive line and the negative line satisfies D(U)>D(U) set , the calculation of the elastic coefficient is started. The first threshold value can generally adopt a preset voltage variance setting value.

[0030] Specifically, whether it is a positive line or a negative line, the calculation formula for current energy is as follows:

[0031]

[0032] Among them, Q represents the current energy, C represents the equivalent capacitance of the internal submodule of the converter, L represents the bridge arm reactance, σ represents the attenuation coefficient of the converter loop, ω represents the angular frequency, and N2 represents a constant.

[0033]

[0034] Among them, U0 represents the initial value of the voltage of the corresponding line (positive line or negative line) collected, I0 represents the initial value of the current of the corresponding line (positive line or negative line) collected, and δ represents the attenuation coefficient of the corresponding line (positive line or negative line).

[0035] Specifically, no matter it is a positive line or a negative line, the calculation formula of the first elastic coefficient is: The calculation formula of the second elastic coefficient is:

[0036] Among them, E M Indicates the first elastic coefficient of one side of the corresponding line (positive line or negative line), E N represents the second elastic coefficient of the other side of the corresponding line (positive line or negative line), Q'(x M ) represents the differential value of the current energy on one side of the corresponding line (positive line or negative line), Q′(x N ) represents the differential value of the current energy on the other side of the corresponding line (positive line or negative line), Indicates the average value of the current on one side of the corresponding line (positive line or negative line), It represents the average value of the current on the other side of the corresponding line (positive line or negative line). It should be understood that when a fault occurs, the above current energy and current are the fault current energy and fault current.

[0037] Step S104: determining the fault position of the DC transmission line of the converter station according to the magnitude relationship between the product of the absolute values ​​of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line and the second threshold.

[0038] Specifically, this step includes the following two situations:

[0039] (1) If the product of the absolute values ​​of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line is greater than the second threshold, it is determined that an in-area fault occurs in the DC transmission line of the converter station.

[0040] The second threshold can be set based on experience. Generally, the second threshold is 1.

[0041] That is, the |E of either the positive line or the negative line M |*|E N |>1, it is determined that an in-area fault occurs on the DC transmission line of the converter station.

[0042] (2) If the product of the absolute values ​​of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line is not greater than the second threshold, it is determined that an out-of-area fault occurs in the DC transmission line of the converter station.

[0043] That is, the |E of either the positive line or the negative line M |*|E N |≤1, it is determined that an out-of-area fault occurs on the DC transmission line of the converter station.

[0044] As Figure 4 The model is shown in the figure. The reason why the elastic coefficient is used as the criterion is explained below.

[0045] First, the frequency characteristics of the distributed capacitor current are analyzed. After a DC grid fault occurs, the fault current is divided into two stages: the discharge current of the converter submodule capacitor and the feed current of the AC system. Since the embodiment of the present invention studies the fault characteristics before the circuit breaker is isolated, only the first stage is analyzed. In the first stage, all submodules of the converter will discharge alternately, and the instantaneous value of the DC current i l for:

[0046]

[0047] The meanings of the symbols in this formula are the same as those mentioned above and will not be repeated here.

[0048] It can be seen from this formula that capacitor discharge is an oscillation process. The calculation formula for the oscillation frequency f of the DC current is as follows:

[0049]

[0050] Among them, L0 represents the bridge arm inductance, L u represents the inductance per unit length of the line, C0 represents the equivalent capacitance of the internal submodule of the converter, R u represents the resistance per unit length of the line, N represents the number of submodules in the bridge arm, and d represents the fault distance.

[0051] When an out-of-zone fault occurs, the main component of the fault current is the transient current of the distributed capacitor, whose frequency is consistent with the natural frequency of the traveling wave. The theoretical minimum value of the natural frequency of the traveling wave is f s It can be expressed as follows:

[0052]

[0053] Where v is the velocity of the fault traveling wave and d is the fault distance.

[0054] Through the above analysis, it can be seen that the frequency of the distributed capacitor current changes with the fault distance. By comparison, it can be seen that the frequencies of the fault current components inside and outside the zone are different. Therefore, this solution uses current energy to filter the distributed capacitor, and the calculation formula of current energy is as described above. Current energy has the function of filtering the high-frequency components of the fault current.

[0055] By performing Laplace transformation on the part that affects the frequency in the current energy calculation formula, the frequency domain formula is as follows:

[0056]

[0057] Here, s represents a complex number, and other symbols have the same meanings as the aforementioned symbols and are not repeated here.

[0058] It can be seen from the above formula that the main component of current energy is low-frequency signal, which means that high-frequency signal is eliminated in the calculation process. That is, the current energy no longer includes high-frequency distributed capacitance current. Therefore, current energy has the ability to suppress current oscillation and eliminate distributed capacitance current.

[0059] When an intra-regional fault occurs, the fault current on both sides of the line increases, and the similarity of the current energy is high. When an extra-regional fault occurs, the fault current on one side of the line increases and the other side decreases, and the similarity of the current energy is low. Therefore, the elasticity coefficient can be selected to express the relationship between the current energy on both sides of the line. The elasticity coefficient is the ratio of the growth rate of two economic indicators related to each other in a certain period of time. In economics, it measures the dependence of the growth rate of one economic variable on the growth rate of another economic variable.

[0060] Therefore, the embodiment of the present invention can use the elasticity coefficient to express the self-similarity of the current energy, that is, when a fault occurs within the zone, the current energy similarity on both sides is high, and the elasticity coefficient is greater than the second threshold (i.e., 1); when a fault occurs outside the zone, the current energy similarity on both sides is low, and the elasticity coefficient is not greater than the second threshold (i.e., 1).

[0061] In summary, the power transmission protection method of the wireless anti-interference converter station of Embodiment 1 of the present invention can preliminarily detect whether the fault of the DC transmission line of the converter station is an internal fault or an external fault.

[0062] Example 2

[0063] Embodiment 2 of the present invention discloses a transmission protection method for a wireless anti-interference converter station. The method is applicable to the case where a single fault occurs in the DC transmission line of the converter station during the detection period. Specifically, Figure 2 As shown, the method comprises the following steps:

[0064] Step S201: collecting the voltage of the DC transmission line of the converter station at preset time intervals.

[0065] Step S202: using the voltage of the positive line and the voltage of the negative line respectively to calculate the voltage variance of each line.

[0066] Step S203: if the voltage variance of the positive line or the negative line is greater than the first threshold, then respectively calculating the first elastic coefficient and the second elastic coefficient of the current energy on both sides of the positive line and the negative line.

[0067] Step S204: determining the fault position of the DC transmission line of the converter station according to the magnitude relationship between the product of the absolute values ​​of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line and the second threshold.

[0068] Steps S201 to S204 are the same as steps S101 to S104 of embodiment 1, and are not described in detail here. If step S204 determines that the fault is an intra-area fault, the following steps are performed.

[0069] Step S205: calculating a first ratio of the absolute values ​​of the first elastic coefficients of the positive electrode circuit to the negative electrode circuit, and calculating a second ratio of the absolute values ​​of the second elastic coefficients of the positive electrode circuit to the negative electrode circuit.

[0070] This calculation requires the use of the elastic coefficient of the positive and negative lines on the same side. Specifically, when the first elastic coefficient is used for calculation, E P Indicates the first elastic coefficient of the positive line, E N Indicates the first elastic coefficient of the negative electrode circuit (similarly, when the second elastic coefficient is used for calculation, E P Indicates the second elastic coefficient of the positive line, E N represents the second elastic coefficient of the negative line), the calculation formula is:

[0071] Step S206: Determine the fault poles on both sides of the DC transmission line of the converter station according to the first ratio and the second ratio respectively.

[0072] Specifically, for the first ratio, this step includes the following three cases:

[0073] (1) If the first ratio is ∞, it is determined that a positive pole fault occurs on the side of the DC transmission line of the converter station corresponding to the first ratio.

[0074] Right now The first ratio of the DC transmission line corresponds to a ground fault in the positive line on one side.

[0075] (2) If the first ratio is 0, it is determined that a negative pole fault occurs on the side of the DC transmission line of the converter station corresponding to the first ratio.

[0076] Right now The first ratio of the DC transmission line corresponds to a ground fault in the negative line on one side.

[0077] (3) If the first ratio is 1, it is determined that a two-pole fault occurs on one side of the DC transmission line of the converter station corresponding to the first ratio.

[0078] Right now The first ratio corresponds to a two-pole short circuit fault on one side of the DC transmission line.

[0079] Similarly, for the second ratio, this step also includes the following three cases:

[0080] (4) If the second ratio is ∞, it is determined that a positive pole fault occurs on the side of the DC transmission line of the converter station corresponding to the second ratio.

[0081] (5) If the second ratio is 0, it is determined that a negative pole fault occurs on the side of the DC transmission line of the converter station corresponding to the second ratio.

[0082] (6) If the first ratio is 1, it is determined that a two-pole fault occurs on one side of the DC transmission line of the converter station corresponding to the second ratio.

[0083] Fault pole selection is an essential part of DC protection. When a single-pole fault occurs, the fault pole current changes greatly, and its current energy elasticity coefficient is more obvious; while there is basically no fault current at the non-fault pole, and its elasticity coefficient is almost zero. Therefore, the embodiment of the present invention uses the ratio of elasticity coefficients as the criterion for fault identification.

[0084] In summary, the power transmission protection of the wireless anti-interference converter station according to Embodiment 2 of the present invention can further detect whether the fault of the DC transmission line of the converter station is a positive pole fault, a negative pole fault or a bipolar fault.

[0085] Example 3

[0086] Embodiment 3 of the present invention discloses a transmission protection method for a wireless anti-interference converter station. The method is applicable to the case where a single fault occurs in the DC transmission line of the converter station during the detection period. Specifically, Figure 3 As shown, the method comprises the following steps:

[0087] Step S301: collecting the voltage of the DC transmission line of the converter station at preset time intervals.

[0088] Step S302: using the voltage of the positive line and the voltage of the negative line respectively to calculate the voltage variance of each line.

[0089] Step S303: if the voltage variance of the positive line or the negative line is greater than the first threshold, then respectively calculating the first elastic coefficient and the second elastic coefficient of the current energy on both sides of the positive line and the negative line.

[0090] Step S304: Determine the fault location of the DC transmission line of the converter station according to the magnitude relationship between the product of the absolute values ​​of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line and the second threshold.

[0091] Step S305: Calculate a first ratio of the absolute values ​​of the first elastic coefficients of the positive electrode circuit to the absolute values ​​of the first elastic coefficients of the negative electrode circuit, and calculate a second ratio of the absolute values ​​of the second elastic coefficients of the positive electrode circuit to the absolute values ​​of the second elastic coefficients of the negative electrode circuit.

[0092] Step S306: Determine the fault poles on both sides of the DC transmission line of the converter station according to the first ratio and the second ratio respectively.

[0093] Steps S301 to S306 are the same as steps S201 to S206 of Example 2, and are not described again here.

[0094] Step S307: Send a trip signal to the fault pole through the protection device on the corresponding side.

[0095] Both sides of the existing DC transmission line are provided with protection devices. Therefore, in this step, the protection devices on different sides are used to send a trip signal to the corresponding side.

[0096] That is, if a positive pole fault is determined by the first ratio, a trip signal is sent to the positive pole through the protection device on the side corresponding to the first ratio; if a negative pole fault is determined by the first ratio, a trip signal is sent to the negative pole through the protection device on the side corresponding to the first ratio; if a two-pole fault is determined by the first ratio, a trip signal is sent to the positive and negative poles through the protection device on the side corresponding to the first ratio; similarly, if a positive pole fault is determined by the second ratio, a trip signal is sent to the positive pole through the protection device on the side corresponding to the second ratio; if a negative pole fault is determined by the second ratio, a trip signal is sent to the negative pole through the protection device on the side corresponding to the second ratio; if a two-pole fault is determined by the second ratio, a trip signal is sent to the positive and negative poles through the protection device on the side corresponding to the second ratio; so as to achieve the purpose of protection.

[0097] In summary, the transmission protection method of the wireless anti-interference converter station of embodiment 3 of the present invention can further determine whether the fault of the DC transmission line of the converter station is a positive pole fault, a negative pole fault or a bipolar fault, thereby sending a corresponding tripping signal to the faulty pole as a fast backup protection solution.

[0098] Example 4

[0099] Embodiment 4 of the present invention discloses a computer-readable storage medium, on which computer program instructions are stored; when the computer program instructions are executed by a processor, a power transmission protection method for a wireless anti-interference converter station as described in any one of the above embodiments 1 to 3 is implemented.

[0100] Example 5

[0101] Embodiment 5 of the present invention discloses a power transmission protection system for a wireless anti-interference converter station, including: a computer-readable storage medium as described in Embodiment 4 above.

[0102] In summary, the embodiments of the present invention use the filtering characteristics of current energy to filter out the distributed capacitor current according to the frequency characteristics of the distributed capacitor current, so that the fault detection and backup protection schemes are not affected by the line distribution parameters, such as transition resistance and line distributed capacitance, and solve the long delay problem of backup protection after the fault is detected; the elasticity coefficient is applied to the fault detection and protection of the power system, and the characteristic of the elasticity coefficient that only the data of the local end needs to be processed and transmitted to the opposite end is used to solve the problem that the current differential protection needs strict communication synchronization, which greatly reduces the communication burden; the current energy and the elasticity coefficient are combined to construct a fault detection and fast backup protection scheme for the DC transmission line that is free from communication interference, so that the scheme is simple and reliable; the present invention provides technical support for the safe and reliable operation of the flexible system.

[0103] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A power transmission protection method for a wireless anti-interference converter station, characterized in that: include: The voltage of the DC transmission line of the converter station is collected at preset intervals, wherein the DC transmission line includes: a positive line and a negative line; The voltage of the positive line and the voltage of the negative line are respectively used to calculate the voltage variance of the respective lines; If the voltage variance of the positive line or the negative line is greater than a first threshold, respectively calculating a first elastic coefficient and a second elastic coefficient of current energy on both sides of the positive line and the negative line; Determining a fault position of the DC transmission line of the converter station according to a magnitude relationship between a product of an absolute value of a first elastic coefficient and a second elastic coefficient of the positive line or the negative line and a second threshold; The calculation formula of the first elastic coefficient is: ; The calculation formula of the second elastic coefficient is: ; in, represents the first elastic coefficient of one side of the corresponding line, represents the second elastic coefficient on the other side of the corresponding line, Represents the differential value of the current energy on one side of the corresponding line, represents the differential value of the current energy on the other side of the corresponding line, represents the average value of the current on one side of the corresponding line, Represents the average value of the current on the other side of the corresponding line.

2. The power transmission protection method of the wireless anti-interference converter station according to claim 1 is characterized in that: The step of determining the fault position of the DC transmission line of the converter station comprises: If the product of the absolute value of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line is greater than the second threshold, it is determined that an in-area fault occurs in the DC transmission line of the converter station; If the product of the absolute values ​​of the first elastic coefficient and the second elastic coefficient of the positive line or the negative line is not greater than the second threshold, it is determined that an out-of-area fault occurs in the DC transmission line of the converter station.

3. The power transmission protection method of the wireless anti-interference converter station according to claim 2 is characterized in that: If an in-area fault occurs, after the step of determining the fault location of the DC transmission line of the converter station, the method further includes: Calculating a first ratio of absolute values ​​of a first elastic coefficient of the positive electrode circuit to that of the negative electrode circuit, and calculating a second ratio of absolute values ​​of a second elastic coefficient of the positive electrode circuit to that of the negative electrode circuit; The fault poles on both sides of the DC transmission line of the converter station are determined respectively according to the first ratio and the second ratio.

4. The power transmission protection method of the wireless anti-interference converter station according to claim 3 is characterized in that: The step of respectively determining the fault poles on both sides of the DC transmission line of the converter station according to the first ratio and the second ratio comprises: If the first ratio is ∞, it is determined that a positive pole fault occurs on the side of the DC transmission line of the converter station corresponding to the first ratio; If the first ratio is 0, it is determined that a negative pole fault occurs on the side corresponding to the first ratio of the DC transmission line of the converter station; If the first ratio is 1, it is determined that a two-pole fault occurs on one side of the DC transmission line of the converter station corresponding to the first ratio; If the second ratio is ∞, determining that a positive pole fault occurs on the side corresponding to the second ratio of the DC transmission line of the converter station; If the second ratio is 0, it is determined that a negative pole fault occurs on the side corresponding to the second ratio of the DC transmission line of the converter station; If the second ratio is 1, it is determined that a two-pole fault occurs on the side corresponding to the first ratio of the DC transmission line of the converter station.

5. The power transmission protection method of the wireless anti-interference converter station according to claim 1, characterized in that: The voltage variance is calculated as: ； in, represents the voltage variance, Indicates the voltage of the corresponding line collected, x Indicates the average value of the voltage of the corresponding line collected, n Indicates the number of voltages collected for the corresponding line.

6. The power transmission protection method of the wireless anti-interference converter station according to claim 1, characterized in that: The calculation formula of the current energy is: ； in, Q represents the current energy, C represents the equivalent capacitance of the internal submodule of the converter, L represents the bridge arm reactance, σ represents the attenuation coefficient of the converter circuit, ω represents the angular frequency, represents a constant; ， ， ； in, Indicates the initial value of the voltage of the corresponding line collected, Indicates the initial value of the current of the corresponding line collected, δ Indicates the attenuation coefficient of the corresponding line.

7. The power transmission protection method of the wireless anti-interference converter station according to claim 3, characterized in that: After the step of respectively determining the fault poles on both sides of the DC transmission line of the converter station according to the first ratio and the second ratio, the method further comprises: A tripping signal is sent to the fault pole through a protection device on the corresponding side.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions; when the computer program instructions are executed by the processor, the power transmission protection method for the wireless anti-interference converter station according to any one of claims 1 to 7 is implemented.

9. A power transmission protection system for a wireless anti-interference converter station, characterized in that: include: The computer readable storage medium of claim 8.

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