A network source boundary switch and its communication method, computer device

Abstract

The present invention belongs to the field of power information technology, and particularly relates to a network-source boundary switch and its communication method. The network-source boundary switch includes a quantum distribution unit. The method includes: the quantum distribution unit receives a communication request message carrying quantum identity number information sent by a photovoltaic power generation source, and this communication request message is encrypted using a public key; the quantum distribution unit decrypts this communication request message using a private key to obtain the quantum identity number information, and queries this quantum identity number information in a pre-stored list of power generation device identifiers; if this quantum identity number information exists, the quantum distribution unit returns an allowed communication request message to the photovoltaic power generation source. The network-source boundary switch in the embodiment of the present invention can encrypt the communication process, thereby ensuring the communication security between the photovoltaic power generation source and the distribution line.

Description

Technical Field

[0001] The present invention belongs to the field of electric power information technology, and particularly relates to a network-source boundary switch and a communication method thereof. Background Art

[0002] With the country's promotion of the construction of distributed photovoltaic power sources, a large number of distributed photovoltaic power sources have begun to be incorporated into the 10kV power grid. At the common connection point of the 10kV distributed power source and the power grid, there is a need to install a network-source boundary switch. On the one hand, when a fault occurs on the grid side, the fault can be quickly removed and the power supply can be cut off; on the other hand, it plays a role in anti-islanding, low-voltage ride-through, and reverse power protection. The 12kV primary-secondary integrated network-source boundary pole-mounted circuit breaker is a boundary switch used for the common connection point between the 10kV source side and the 10kV grid side. It uses a current transformer to collect signals and cooperate with the terminal to realize the boundary switch function.

[0003] The current communication encryption method of the network-source boundary switch is relatively simple and is easily cracked after being intercepted during transmission, thus leaking its communication information.

[0004] How to provide a secure communication method for the network-source boundary switch is an urgent problem to be solved at present. Summary of the Invention

[0005] Embodiments of the present invention provide a network-source boundary switch and a communication method thereof to solve the problem that the communication information of the network-source boundary switch in the prior art is easily cracked. To have a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary part is not a general review, nor is it intended to identify key / important constituent elements or delineate the protection scope of these embodiments. Its sole purpose is to present some concepts in a simple form as a prelude to the subsequent detailed description.

[0006] According to a first aspect of an embodiment of the present invention, a communication method for a network-source boundary switch is provided.

[0007] In one embodiment, the network-source boundary switch includes a quantum distribution unit, and the method includes:

[0008] The quantum distribution unit receives a communication request message carrying quantum identity number information sent by a photovoltaic power source, and the communication request message is encrypted using a public key;

[0009] The quantum distribution unit decrypts the communication request message using a private key, obtains the quantum identity number information, and queries the quantum identity number information in a pre-stored power generation device identification list;

[0010] If the quantum identity number information exists, the quantum distribution unit returns an allowed communication request message to the photovoltaic power source.

[0011] Optionally, the public key is obtained through the following steps:

[0012] Step S21: Randomly select p and q, and define n = p × q, where p and q are prime numbers to each other;

[0013] Step S22: Calculate Then randomly select e, where e and are prime numbers to each other;

[0014] Step S23: Calculate where k is a natural number for which d satisfies being a positive integer, and derive Transform it into where mod represents the modulo operator;

[0015] Step S24: (e, n) is the public key.

[0016] Optionally, the steps of encrypting the communication request message using the public key include:

[0017] The photovoltaic power source encrypts the quantum identity number information x into a ciphertext m using the public key and sends the ciphertext to the quantum distribution unit. The encryption formula is as follows:

[0018] x e mod n = m

[0019] where x is a natural number and x < n.

[0020] Optionally, the steps of the quantum distribution unit decrypting the communication request message using the private key include:

[0021] The quantum distribution unit decrypts the communication request message using the private key (d, n). The decryption formula is as follows:

[0022] m d mod n = x.

[0023] According to the second aspect of the embodiments of the present invention, a network-source boundary switch is provided.

[0024] In one embodiment, the network-source boundary switch includes: a distribution line, a digitization unit, a switch unit, and a quantum distribution unit; where

[0025] The digitization unit collects the input voltage signal, output voltage signal, and current signal of the distribution line and transmits them to the distribution terminal;

[0026] The switch unit is arranged on the distribution line, and the switch unit is connected to the digitization unit;

[0027] A quantum distribution unit receives a communication request message carrying quantum identity number information sent by a photovoltaic power source, and the communication request message is encrypted using a public key; the quantum distribution unit decrypts the communication request message using a private key to obtain the quantum identity number information, and queries the quantum identity number information in a pre-stored list of power generation equipment identifiers; if the quantum identity number information exists, the quantum distribution unit returns an allowed communication request message to the photovoltaic power source.

[0028] Optionally, the grid-source boundary switch further includes:

[0029] A distribution line, a digitalization unit, and a switch unit; where

[0030] The digitalization unit collects the input voltage signal, output voltage signal, and current signal of the distribution line and transmits them to the distribution terminal;

[0031] The switch unit is arranged on the distribution line, the switch unit is connected to the digitalization unit, and the digitalization unit collects the working state of the switch unit.

[0032] Optionally, the grid-source boundary switch further includes a low-voltage ride-through module, and the judgment method of the low-voltage ride-through module includes:

[0033] When the maximum voltage U among the three-phase voltages max is less than or equal to U dmin and the duration is greater than T dmin or U max is greater than U dmin and less than U dmax and the duration is greater than T u , then the low-voltage ride-through module outputs a protection action signal to the switch unit to drive the switch unit to trip;

[0034] T u = 1.962 * U max / U n + 0.233 (1)

[0035] where, T u represents the low-voltage ride-through time, U max is the maximum voltage among the three-phase voltages at the grid connection point, U n is the rated voltage; U dmin represents the lower limit of the limited voltage; U dmax represents the upper limit of the limited voltage; T dmin represents the lower limit of the limited time.

[0036] Optionally, the grid-source boundary switch further includes an anti-islanding protection module, and the judgment method of the anti-islanding protection module includes:

[0037] After training, an LSTM model is obtained. The target parameters are input into the trained LSTM model to determine islanding events.

[0038] Optionally, the training method of the LSTM model includes:

[0039] Step S1: Select the target distributed power source as the research object, set the operating parameters of the distribution line, so that the distribution line obtains islanding events and non-islanding events under different states. After simulation, extract the voltage, voltage change rate, frequency, frequency change rate, and power angle at its grid connection point, the sampling time △T, and generate a training data set and normalize it;

[0040] Step S2: For each training feature matrix, there is a corresponding class label. Use y = [0 1] to represent non-islanding events and y = [1 0] to represent islanding events;

[0041] Step S3: After obtaining the data set for training, train the model with the corresponding LSTM structure to obtain the trained LSTM model.

[0042] Optionally, the method for judging islanding events includes:

[0043] Step S11: Collect the voltage, voltage change rate, frequency, frequency change rate, and power angle at the grid connection point of the target distributed power source within △T time at time T, form a feature matrix X and normalize it;

[0044] Step S12: Input the feature matrix X into the already trained LSTM model and obtain the output y;

[0045] Step S13: If y = [1 0], it indicates an islanding event, and a tripping signal is sent to act on the switch unit. If y = [0 1], it indicates a non-islanding event.

[0046] According to the third aspect of the embodiments of the present invention, a computer device is provided.

[0047] In some embodiments, the computer device includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the above method are implemented.

[0048] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

[0049] The grid-source disconnection switch can encrypt the communication process, thereby ensuring the communication security between the photovoltaic power source and the distribution line.

[0050] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present invention. Description of the Drawings

[0051] The accompanying drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present invention, and are used together with the specification to explain the principles of the present invention.

[0052] Figure 1 is a structural diagram of a network-source boundary switch shown according to an exemplary embodiment;

[0053] Figure 2 is a flowchart of a network-source boundary switch communication method shown according to an exemplary embodiment;

[0054] Figure 3 is an overvoltage protection logic diagram shown according to an exemplary embodiment;

[0055] Figure 4 is an undervoltage protection logic diagram shown according to an exemplary embodiment;

[0056] Figure 5 is a high-frequency protection logic diagram shown according to an exemplary embodiment;

[0057] Figure 6 is a low-frequency protection logic diagram shown according to an exemplary embodiment;

[0058] Figure 7 is a schematic diagram of low voltage ride-through shown according to an exemplary embodiment;

[0059] Figure 8 is a low voltage ride-through protection logic diagram shown according to an exemplary embodiment;

[0060] Figure 9 is an anti-islanding protection logic diagram shown according to an exemplary embodiment;

[0061] Figure 10 is a reverse power protection logic diagram shown according to an exemplary embodiment;

[0062] Figure 11 is a network-side incoming power delayed closing logic diagram shown according to an exemplary embodiment.

[0063] Figure 12 is a schematic structural diagram of a computer device shown according to an exemplary embodiment. Detailed implementation manners

[0064] The following description and the accompanying drawings fully illustrate specific embodiments herein, enabling those skilled in the art to practice them. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments herein includes the entire scope of the claims and all available equivalents of the claims. In this document, the terms "first", "second", etc. are only used to distinguish one element from another, without requiring or implying any actual relationship or order between these elements. In fact, the first element can also be called the second element, and vice versa. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, such that a structure, device or equipment comprising a series of elements not only includes those elements, but also includes other elements not explicitly listed, or elements inherent to such structure, device or equipment. Without further limitation, an element defined by the statement "comprising one..." does not exclude the existence of additional identical elements in the structure, device or equipment comprising the element. The embodiments herein are described in a progressive manner, with each embodiment highlighting the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0065] The terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. in this document indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this document and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation on the present invention. In the description herein, unless otherwise specified and limited, the terms "mounted", "connected", "coupled" shall be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the communication inside two elements. It can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0066] In this document, unless otherwise stated, the term "plurality" means two or more.

[0067] In this document, the character " / " indicates that the objects before and after are in an "or" relationship. For example, A / B means: A or B.

[0068] In this document, the term "and / or" is an associative relationship describing an object, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B these three relationships.

[0069] Without conflict, the embodiments in the present invention and the features in the embodiments may be combined with each other.

[0070] Figure 1 An embodiment of the network-source boundary switch of the present invention is shown.

[0071] In this alternative embodiment, the network-source boundary switch includes: a distribution line, a digitalization unit, a switch unit, and a quantum distribution unit.

[0072] Two independent voltage sensors are connected to both sides of the digitalization unit. The two voltage sensors are respectively electrically connected to the input end and the output end of the distribution line. The distribution line is electrically connected to a distribution terminal, and the digitalization unit is also connected to a current sensor; the digitalization unit is used to collect the analog small signals of the voltage sensor and the current sensor, convert them into digital signals, and then transmit them to the distribution terminal through an isolated twisted pair.

[0073] The switch unit includes an arc extinguishing chamber and an isolating switch arranged on the distribution line. The switch unit is connected to the digitalization unit, and the digitalization unit collects the working state of the switch unit.

[0074] The network-source boundary switch communication method includes the following steps:

[0075] The quantum distribution unit receives a communication request message carrying quantum identity number information sent by a photovoltaic power source. The communication request message is encrypted with a public key; the quantum distribution unit decrypts the communication request message with a private key to obtain the quantum identity number information, and queries the quantum identity number information in a pre-stored power generation device identification list; if the quantum identity number information exists, the quantum distribution unit returns an allowed communication request message to the photovoltaic power source, as Figure 2 shown.

[0076] The quantum distribution unit assigns a unique identity identifier (quantum identity number information) to each registered photovoltaic power source. A power generation device identification list is stored in the quantum distribution unit, and each piece of data in the power generation device identification list is a mapping relationship between the photovoltaic power source and the quantum identity number information.

[0077] Before the photovoltaic power source sends the quantum identity number information to the quantum distribution unit, it is encrypted with a public key, and the public key is the public key announced by the quantum distribution unit to the photovoltaic power source.

[0078] Optionally, as Figure 2 shown, the step of encrypting the communication request message with a public key includes:

[0079] Step S21: Select p and q, and define n = p × q, where p and q are prime numbers to each other;

[0080] Step S22: Calculate Then randomly select e, where e and are relatively prime;

[0081] Step S23: Calculate where k is a natural number for which d satisfies being a positive integer, and it can be deduced that the product of de divided by has a remainder of 1, which can be written as where mod represents the modulo operator;

[0082] Step S24: (e, n) is the public key, and (d, n) is the private key;

[0083] Step S25: The photovoltaic power source encrypts the quantum identity number information x into the ciphertext m using the public key and sends the ciphertext to the quantum distribution unit, where x e mod n = m, where x is a natural number and x < n.

[0084] After receiving the sending communication request, the quantum distribution unit decrypts the communication request message using the private key (d, n), where m d mod n = x.

[0085] In the above step S22, is the Euler's totient function. Since both p and q are prime numbers, so According to the Euler's totient function, if p and q are relatively prime, then Substitute and into it, and then we get That is

[0086] In the above step S23, since k is a natural number of a positive integer, thus de is equal to an integer multiple of So it can be expressed as

[0087] In the above step S25, the encryption formula can be converted to:

[0088] x e = kn + m, m = x e - kn

[0089] Substitute it into the decryption formula to get:

[0090] (x e - kn) d mod n = x

[0091] Further convert it to: (x e - kn) d = kn + x

[0092] If the left side of the equation is expanded as a quadratic term, the following can be obtained:

[0093] x ed +k 1 n = kn + x, which is equivalent to x ed = k 丿 n + x, that is, x ed mod n = x;

[0094] Substituting into it, the following can be obtained:

[0095] According to Euler's theorem, where a and x are positive integers and are relatively prime. In this application, x < n, n = p × q, and p and q are prime numbers to each other. After conversion, Taking the k-th root to obtain, After expanding the right side of the equation as a quadratic term, the following is obtained: Multiplying both sides of the equation by x gives Therefore, it can be expressed as That is Therefore, after decrypting with the decryption formula, the quantum identity number information x can be obtained.

[0096] Among them, mod is used as the modulo operator, taking advantage of the irreversibility of modular arithmetic. Only through the d value of the private key can the quantum identity number information x be obtained, and the acquisition of the d value requires knowing value, and is obtained from p and q that are prime numbers to each other. Therefore, after obtaining the public key and the private key, only by deleting the values of p and q can the reliability of the algorithm be ensured.

[0097] When the quantum distribution unit decrypts with the private key to obtain the quantum identity number information x, by querying the data information in the power generation equipment identification list, if the quantum identity number information x exists in the power generation equipment identification list, the corresponding communication work is carried out, thus realizing the encryption of the communication transmission process.

[0098] The digitalization unit includes: an AD module, a digital input module, a coding circuit, and an isolated power supply. The AD module, the digital input module, and the isolated power supply are all electrically connected to the coding circuit. The digital input module is connected to the switch unit to collect the working state of the switch unit. The voltage sensor and the current sensor are both connected to the AD module. The coding circuit is electrically connected to the power distribution line. The coding circuit is used to receive the output signals of the AD module, the digital input module, and the isolated power supply, and convert them into electrical signals and send them to the power distribution line.

[0099] The digital unit collects the analog small signals of the electronic voltage sensor and current sensor, converts them into digital signals through the AD module, and transmits them to the power distribution terminal outside the switch through isolated twisted pairs. Since digital signals have higher anti-interference ability than analog small signals in long-distance transmission, bilateral voltage sampling can be achieved, and the problem of long-distance transmission of analog small signals of electronic sensors is solved. It is very suitable for isolating grid-side and power-side faults at the grid-source boundary point.

[0100] The grid-source boundary switch also includes an overvoltage protection module and an undervoltage protection module. When the voltage at the grid connection point exceeds or is lower than the specified voltage range, the overvoltage protection module or the undervoltage protection module protects and trips within the corresponding time, that is, the overvoltage protection module or the undervoltage protection module outputs a protection action signal to the switch unit within the corresponding time to drive the switch unit to trip and stop the distributed power supply from sending power to the grid. The voltage protection action setting value and action time limit can be set.

[0101] The overvoltage protection of the overvoltage protection module is divided into overvoltage stage I protection and overvoltage stage II protection. The action logic of the overvoltage stage I protection is shown in Figure 3 Under the condition that the overvoltage stage I protection function is enabled, when the line voltages are all greater than the overvoltage stage I setting value and after the overvoltage stage I time, the overvoltage protection module outputs a protection action signal to the switch unit to drive the switch unit to trip. The action logic of the overvoltage stage II protection is the same as that of the overvoltage stage I.

[0102] The undervoltage protection of the undervoltage protection module is divided into stage I and stage II. The action logic of the undervoltage stage I protection is shown in Figure 4 Under the condition that the undervoltage stage I protection function is enabled, when the line voltages are all less than the undervoltage stage I setting value and after the undervoltage stage I time, the undervoltage protection module outputs a protection action signal to the switch unit to drive the switch unit to trip. The action logic of the undervoltage stage II protection is the same as that of the overvoltage stage I.

[0103] The grid-source boundary switch also includes an overfrequency protection module and a low-frequency protection module. When the grid connection point frequency exceeds or is lower than the specified operating range, the overfrequency protection module or the low-frequency protection module protects and trips within the corresponding time, that is, it outputs a protection action signal to the switch unit within the corresponding time to drive the switch unit to trip and stop sending power to the grid line. The protection action time limit and action setting value can be set.

[0104] The high-frequency protection of the overfrequency protection module is divided into stage I and stage II. The action logic of the high-frequency stage I protection is shown in Figure 5 Under the condition that the high-frequency stage I protection function is enabled, when the frequency is greater than the high-frequency stage I setting value and after the high-frequency stage I time, the overfrequency protection module outputs a protection action signal to the switch unit to drive the switch unit to trip. The action logic of the high-frequency stage II protection is the same as that of the high-frequency stage I.

[0105] The low-frequency protection of the low-frequency protection module is divided into section I and section II. The operation logic of the low-frequency section I protection can be seen in Figure 6 , under the condition that the low-frequency section I protection function is enabled, when the frequency is less than the low-frequency section I setting value, after the low-frequency section I time, the low-frequency protection module outputs a protection operation signal to the switch unit to drive the switch unit to trip. The operation logic of the low-frequency section II protection is the same as that of the low-frequency section I.

[0106] The grid-source disconnection switch also includes a low-voltage ride-through module. The judgment method of the low-voltage ride-through module includes:

[0107] When the maximum voltage U among the three-phase voltages max is less than or equal to U dmin and the duration is greater than T dmin or U max is greater than U dmin and less than U dmax and the duration is greater than T u , then the low-voltage ride-through module outputs a protection operation signal to the switch unit to drive the switch unit to trip;

[0108] T u =1.962*U max / U n +0.233 (1)

[0109] where, T u represents the low-voltage ride-through time, U max is the maximum voltage among the three-phase voltages at the grid connection point, U n is the rated voltage; U dmin represents the lower limit of the limited voltage; U dmax represents the upper limit of the limited voltage; T dmin represents the lower limit of the limited time; According to Figure 7 , U dmax =0.85U n , T dmax =1.9s; U dmin =0.2Un, T dmin =0.635s.

[0110] The operation logic of the low-voltage ride-through protection of the low-voltage ride-through module can be seen in Figure 8 , when the "fault handling" lever on the terminal panel is turned on and the low-voltage ride-through protection function is enabled, when the maximum voltage among the three-phase voltages Umax is less than or equal to U dmin and the duration is greater than T dmin or U max is greater than U dmin and less than U dmax and the duration is greater than T uIf so, the low-voltage ride-through module outputs a protection action signal to the switch unit to drive the switch unit to trip.

[0111] The grid-source boundary switch further includes an anti-islanding protection module. The anti-islanding protection module has the ability to monitor anti-islanding protection and immediately disconnect from the power grid, and can set the anti-islanding protection action time and action setting value. For the anti-islanding protection action logic, see Figure 9 Under the conditions that the "fault handling" lever on the terminal panel is turned on and the anti-islanding protection function is turned on, when the voltage and frequency mutation is greater than the voltage and frequency mutation setting value, after the anti-islanding protection delay, the anti-islanding protection module outputs a protection action signal to the switch unit to drive the switch unit to trip.

[0112] The method for judging the anti-islanding protection module includes: obtaining an LSTM model through training, inputting the target parameters into the trained LSTM model, and performing anti-islanding event judgment.

[0113] The method for training the LSTM model includes:

[0114] S1: Select the target distributed power source as the research object, set the operating parameters of the transmission line, so that the transmission line obtains anti-islanding events and non-anti-islanding events in different states. After simulation, extract the voltage, voltage change rate, frequency, frequency change rate and power angle at its grid connection point, the sampling time △T, and generate a training data set and normalize it;

[0115] S2: For each training feature matrix, there is a corresponding class label. Use y = [0 1] to represent non-anti-islanding events, and use y = [1 0] to represent anti-islanding events;

[0116] S3: After obtaining the data set for training, use the corresponding LSTM structure to train the model to obtain the trained LSTM model;

[0117] The method for judging anti-islanding events includes:

[0118] S11: Collect the voltage, voltage change rate, frequency, frequency change rate and power angle at the grid connection point of the target distributed power source within the △T time at time T, form a feature matrix X and normalize it;

[0119] S12: Input the feature matrix X into the already trained LSTM model and obtain the output y;

[0120] S13: If y = [1 0], it means an anti-islanding event, send a tripping signal to act on the switch unit. If y = [0 1], it means a non-anti-islanding event.

[0121] The method for judging the anti-islanding protection module further includes: weighting the data information obtained from the data set to improve the ability of the training data to carry feature information, and using the weighted training data for LSTM model training.

[0122] To obtain a reasonable architecture of the LSTM distributed power source islanding detection model, the embodiments of this application use the trial-and-error method to obtain the number of layers of the model and the number of LSTMs in each layer. Since the dimension of the input feature quantity is 5, the number of hidden layers is not easy to be too large. Therefore, the number of basic units of the hidden layer LSTM is selected from the set {10, 20, 30} each time, and the number of layers is determined. The number of layers is increased layer by layer from the first layer until the classification accuracy of the model no longer increases.

[0123] The grid-source disconnection switch further includes a reverse power protection module. When the grid side transmits power reversely to the source side and exceeds the limit value, the switch protection trips after the reverse power protection exits. The operating setting value and operating time limit of the reverse power protection can be set. See the reverse power protection operation logic in Figure 10 ... Under the conditions that the "fault handling" lever on the terminal panel is turned on and the reverse power protection function is turned on, when the power direction is positive (the current flows from the grid side to the source side), and the maximum phase current (I max ) is greater than the reverse power current setting value, after the reverse power protection exit delay, the reverse power protection module outputs a protection action signal to the switch unit to drive the switch unit to trip.

[0124] The grid-source disconnection switch further includes a grid-side incoming power delayed closing module. See the grid-side incoming power delayed closing logic in Figure 11 ... Under the condition that the grid-side incoming power delayed closing function is turned on, when the grid-source disconnection switch is in the open state, when the grid-side voltage is greater than the energized setting value and the incoming power time is greater than the delayed closing time setting value, the grid-source disconnection switch automatically closes.

[0125] The digital unit is used to collect three-phase measured current, zero-sequence protection current, three-phase phase voltages on the grid side and the source side, three-phase protection circuits, zero-sequence voltage and telemetry data. The telemetry data includes the operation state monitoring data of the switch body, and can calculate the active power, reactive power, power factor, frequency and electric energy. The telemetry data includes open position, closed position, not energized, low air pressure lockout, the sampling frequency is 8 kHz, and the transmission delay < 500 uS.

[0126] Optionally, the physical layer of the digital signal transmission is implemented by using a copper wire type shielded cable for transmission. The digital signal uses the FT3 format message. This format has good data integrity, and its frame structure makes it possible to be used for high-speed multi-point network synchronous data links.

[0127] The embodiments of this application also disclose a grid-source disconnection switch communication method. The grid-source disconnection switch includes a quantum distribution unit, as Figure 2As shown, the method includes: a quantum distribution unit receives a communication request message carrying quantum identity number information sent by a photovoltaic power source, and the communication request message is encrypted using a public key; the quantum distribution unit decrypts the communication request message using a private key to obtain the quantum identity number information, and queries the quantum identity number information in a pre-stored list of power generation device identifiers; if the quantum identity number information exists, the quantum distribution unit returns an allowed communication request message to the photovoltaic power source.

[0128] The working principle of the network-source boundary switch communication method disclosed in the embodiments of this application is the same as that of the quantum distribution unit of the network-source boundary switch in the above embodiments, and will not be elaborated here.

[0129] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as Figure 12 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 static information and dynamic information data. 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, the steps in the above method embodiments are implemented.

[0130] Those skilled in the art can understand that Figure 12 the structure shown is only a block diagram of a part of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device to which the solution of the present invention is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0131] In one embodiment, a computer device is further provided, including a memory and a processor. A computer program is stored in the memory, and when the processor executes the computer program, the steps in the above method embodiments are implemented.

[0132] 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 steps in the above method embodiments are implemented.

[0133] 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, storage, database, or other medium used in the embodiments provided by the present invention 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, or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. 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.

[0134] The present invention is not limited to the structures that have been described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is only limited by the appended claims.

Claims

1. A communication method for a network-source boundary switch, characterized in that, the network-source boundary switch includes a quantum distribution unit, and the method includes: The quantum distribution unit receives a communication request message carrying quantum identity number information sent by a photovoltaic power source, and this communication request message is encrypted using a public key; The quantum distribution unit decrypts this communication request message using a private key to obtain the quantum identity number information, and queries this quantum identity number information in a pre-stored power generation equipment identification list; If this quantum identity number information exists, the quantum distribution unit returns an allowed communication request message to the photovoltaic power source; The public key is obtained through the following steps: Step S21: Randomly select p and q, define n = p×q, where p and q are prime numbers to each other; Step S22: Calculate Then randomly select e, where e and are relatively prime to each other; Step S23: Calculate where k is a natural number for which d is a positive integer, and deduce Transform to where mod represents the modulo operator; Step S24: (e, n) is the public key.

2. A communication method for a network-source boundary switch according to claim 1, characterized in that, the step of encrypting the communication request message using a public key includes: The photovoltaic power source encrypts the quantum identity number information x into ciphertext m using the public key and sends this ciphertext to the quantum distribution unit. The encryption formula is as follows: xe mod n = m where x is a natural number and x < n.

3. A communication method for a network-source boundary switch according to claim 2, characterized in that, the step of the quantum distribution unit decrypting this communication request message using a private key includes: The quantum distribution unit decrypts the communication request message using the private key (d, n). The decryption formula is as follows: md modn = x.

4. A network-source boundary switch, characterized in that, it includes a quantum distribution unit, and the quantum distribution unit communicates using the method according to any one of claims 1 to 3.

5. A network-source boundary switch according to claim 4, characterized in that, the network-source boundary switch further includes: a distribution line, a digitalization unit, and a switch unit; wherein, The digitalization unit collects the input voltage signal, output voltage signal, and current signal of the distribution line and transmits them to the distribution terminal; The switch unit is arranged on the distribution line, the switch unit is connected to the digitalization unit, and the digitalization unit collects the working state of the switch unit.

6. A network-source boundary switch according to claim 5, characterized in that, the network-source boundary switch further includes a low voltage ride-through module, and the judgment method of the low voltage ride-through module includes: When the maximum voltage U among the three-phase voltages max is less than or equal to U dmin and the duration is greater than T dmin or U max is greater than U dmin and less than U dmax and the duration is greater than T u , the low-voltage ride-through module outputs a protection action signal to the switch unit to drive the switch unit to trip; T u = 1.962 * U max / U n + 0.233 (1) Among them, T u represents the low voltage ride-through time, U max is the maximum voltage among the three-phase voltages at the point of common coupling, U n is the rated voltage; U dmin represents the lower limit of the limited voltage; U dmax represents the upper limit of the limited voltage; T dmin represents the lower limit of the limited time.

7. A network-source boundary switch according to claim 6, characterized in that, it further includes an anti-islanding protection module, and the judgment method of the anti-islanding protection module includes: An LSTM model is obtained through training, and the target parameters are input into the trained LSTM model to perform anti-islanding event judgment.

8. A network-source boundary switch according to claim 7, characterized in that, the training method of the LSTM model includes: Step S1: Select the target distributed power source as the research object, set the operating parameters of the distribution line so that the distribution line obtains anti-islanding events and non-anti-islanding events under different states. After simulation, extract the voltage, voltage change rate, frequency, frequency change rate, and power angle at its grid connection point, the sampling time △T, and generate a training data set and normalize it; Step S2: For each training feature matrix, a class label is corresponding. Let y = [0 1] represent a non-islanding event, and y = [1 0] represent an islanding event. Step S3: After obtaining the dataset for training, use the corresponding LSTM structure to train the model to obtain a trained LSTM model.

9. A network-source boundary switch as claimed in claim 8, wherein, the method for judging the islanding event includes: Step S11: Collect the voltage, voltage change rate, frequency, frequency change rate, and power angle at the grid connection point of the target distributed power source within ΔT time at time T, form a feature matrix X and normalize it; Step S12: Input the feature matrix X into the trained LSTM model and obtain the output y; Step S13: If y = [1 0], it indicates an islanding event, and a tripping signal is sent to act on the switch unit. If y = [0 1], it represents a non-islanding event.

10. A computer device, including a memory and a processor, the memory stores a computer program, wherein, when the processor executes the computer program, it implements the steps of a network-source boundary switch communication method. The network-source boundary switch includes a quantum distribution unit, and the method includes: The quantum distribution unit receives a communication request message carrying quantum identity number information sent by a photovoltaic power source, and this communication request message is encrypted using a public key; The quantum distribution unit decrypts this communication request message using a private key to obtain the quantum identity number information, and queries this quantum identity number information in the pre-stored power generation device identification list; If this quantum identity number information exists, the quantum distribution unit returns an allowed communication request message to the photovoltaic power source; The public key is obtained through the following steps: Step S21: Randomly select p and q, and define n = p × q, where p and q are prime numbers to each other; Step S22: Calculate Then randomly select e, where e and are relatively prime to each other; Step S23: Calculate where k is a natural number for which d is a positive integer, and derive Transform it into where mod represents the modulo operator; Step S24: (e, n) is the public key.

11. A computer device as claimed in claim 10, wherein, the step of encrypting the communication request message using a public key includes: The photovoltaic power source encrypts the quantum identity number information x into a ciphertext m using the public key and sends this ciphertext to the quantum distribution unit. The encryption formula is as follows: x^e mod n = m where x is a natural number and x < n.

12. A computer device as claimed in claim 11, wherein, the step of the quantum distribution unit decrypting this communication request message using a private key includes: The quantum distribution unit decrypts the communication request message using the private key (d, n). The decryption formula is as follows: m^d mod n = x.

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