Power distribution network communication signal protection system

Abstract

The invention relates to the technical field of power distribution network communication signal protection, and discloses a power distribution network communication signal protection system, which comprises a voltage clamping module for preventing a communication signal from exceeding a preset voltage range, and a protection module for filtering an interference signal of the communication signal and processing noise of the communication signal, the signal processing module is used for establishing a transient interference model to limit a transient amplitude; the detection module is used for extracting communication information and monitoring and measuring the voltage of the power distribution network communication signal protection system; the feedback module is used for feeding back the maximum clamping voltage of the power distribution network communication signal protection system and feeding back the maximum clamping voltage of the power distribution network communication signal protection system, and the adjusting and optimizing module is used for adjusting the communication signal detection model, so that the communication signal detection algorithm is simple, the input cost is low, and the later maintenance and upgrading are convenient.

Description

Technical Field

[0001] The invention relates to the technical field of distribution network communication signal protection and discloses a distribution network communication signal protection system. Background Art

[0002] The communication signal protection system of the distribution network plays a vital role in the modern power system, but there are still some shortcomings in practical applications. The communication system of the distribution network needs to operate stably under various environmental conditions, but due to equipment failure or network interference, the reliability and stability of the system are sometimes affected. This requires more attention to the redundant design and fault recovery capabilities of the system during the design and maintenance process. With the improvement of the intelligence level of the distribution network, the amount and complexity of the generated data are also increasing. The existing protection system may have deficiencies in data processing and analysis capabilities, resulting in insufficient timely or accurate response to abnormal situations. The communication signal is restricted by the performance of the communication circuit module itself, and the temperature fluctuates greatly, affecting the distortion of the communication signal. The communication signal test method is easily affected by noise. Therefore, a new communication signal processing method and a system for protecting the temperature stability of the communication circuit are urgently needed.

[0003] For example, the existing Chinese patent with the authorization publication number CN103548281A discloses a method for detecting a signal sent on one phase of a multi-phase power distribution system, wherein components of the signal appear concurrently on all phases of the system. The method includes: detecting the components of each signal appearing on each phase of the system, including the neutral phase. The detected signals are provided to a signal processor, which processes them to generate a detection signal that is a combination of all components. The signals are combined through a weighted summation scheme, taking into account the signal and noise correlation to maximize the signal strength and suppress noise at the same time. If there are other signals on other phases of the system, all synthetic interferences are eliminated from the detected signal to further improve the quality of the detected signal.

[0004] However, the above patent has the following problems: the transmission and reception of communication signals by the distribution network communication circuit is greatly affected by temperature, and the frequent communication in the distribution network causes large temperature changes, the ability to optimize the temperature coefficient is poor, the circuit is easily burned out, and no optimization plan is adopted for noise filtering and suppression, which makes the communication signal processing too simple and only considers the correlation between signal and noise.

[0005] The communication signal detection test is not accurate enough to provide timely feedback on the effects of communication signal noise, voltage, and temperature. Summary of the invention

[0006] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In order to solve the above technical problems, the main purpose of the present invention is to provide a distribution network communication signal protection system, comprising:

[0008] A voltage clamp module, used to prevent the communication signal from exceeding a predetermined voltage range;

[0009] A signal processing module, comprising a filtering unit, a noise unit and a transient interference unit, wherein the filtering unit is used to filter interference signals of communication signals, the noise unit is used to process noise of communication signals, and the transient interference unit is used to establish a transient interference model to limit transient amplitude;

[0010] A detection module, comprising a communication signal detection unit and a voltage detection unit, wherein the communication signal detection unit is used to extract communication information, and the voltage detection unit is used to monitor and measure the voltage of the communication signal protection system of the distribution network;

[0011] The feedback module includes a voltage clamping feedback unit and a filtering feedback unit, wherein the voltage clamping feedback unit is used to feed back the maximum clamping voltage of the distribution network communication signal protection system, and the voltage clamping feedback unit is used to feed back the maximum clamping voltage of the distribution network communication signal protection system;

[0012] A tuning module is used to adjust the communication signal detection model.

[0013] As a preferred solution of a distribution network communication signal protection system of the present invention, wherein:

[0014] The voltage clamping module includes a clamping circuit and a power supply circuit;

[0015] The clamping circuit includes a first Zener diode, a second Zener diode, a third Zener diode, a fourth Zener diode, a fifth Zener diode, a first resistor, a triode, and a second resistor;

[0016] The current source circuit includes a first MOS tube, a second MOS tube, a third MOS tube, a fourth MOS tube, a fifth MOS tube and a third resistor;

[0017] The first Zener diode, the first MOS tube source, the second MOS tube source, the third MOS tube source and the transistor collector are all connected to a power supply;

[0018] The Zener breakdown voltages of the first Zener diode, the second Zener diode, the third Zener diode, the fourth Zener diode, and the fifth Zener diode and the base-emitter voltage of the transistor all have negative temperature coefficients.

[0019] As a preferred solution of a distribution network communication signal protection system of the present invention, wherein:

[0020] The maximum clamping voltage of the communication signal of the distribution network is calculated, and then the maximum voltage of the communication signal is monitored. The communication signal is optimized by the voltage clamping module. The maximum clamping voltage calculation expression is as follows:

[0021] V max =V 1 ×[1+T C ×(T X -z)]×(1+t);

[0022] Among them, V max is the maximum clamping voltage of the distribution network communication signal protection system, V 1 is the rated voltage of the Zener diode, T C is the temperature drift coefficient, T X is the actual operating temperature of the transistor, z is the room temperature, and t is the voltage difference of the clamping voltage.

[0023] As a preferred solution of a distribution network communication signal protection system of the present invention, wherein:

[0024] The filtering unit is used to filter high-frequency noise and interference in the communication signal;

[0025] The noise unit is used to process random noise in the signal;

[0026] The transient interference unit is used to deal with short-term high-amplitude interference signals.

[0027] As a preferred solution of a distribution network communication signal protection system of the present invention, wherein:

[0028] The filtering unit is a bandpass filter, which blocks signals of other frequencies and filters high-frequency noise and interference in the communication signal. The calculation table is as follows

[0029]

[0030] Where H(f) is the communication signal frequency allowed to pass by the bandpass filter, f is the input communication signal frequency, and f c is the high frequency cutoff frequency of the bandpass filter, f b is the low frequency cutoff frequency of the bandpass filter;

[0031] The noise unit is used to process additive noise. The noise is processed by establishing a random noise variable model. The calculation expression of the random noise variable model is as follows:

[0032] y(t)=x(t)+n(t)

[0033] Where y(t) is the received communication signal, x(t) is the original communication signal, n(t) is the noise signal, and t is the time sequence;

[0034] The transient interference unit limits the transient amplitude by clamping the voltage through the transient interference model. The calculation expression of the transient interference model is as follows:

[0035]

[0036] Where A is the communication signal interference amplitude, t 0 is the interference start time, t is the timing, rect() is the rectangular pulse function, τ is the interference duration, and i(t) is the pulse signal.

[0037] As a preferred solution of a distribution network communication signal protection system of the present invention, wherein:

[0038] The filtering unit is a bandpass filter, which blocks signals of other frequencies and filters high-frequency noise and interference in the communication signal. The calculation table is as follows

[0039]

[0040] Where H(f) is the communication signal frequency allowed to pass by the bandpass filter, f is the input communication signal frequency, and f c is the high frequency cutoff frequency of the bandpass filter, f b is the low frequency cutoff frequency of the bandpass filter;

[0041] The noise unit is used to process additive noise. The noise is processed by establishing a random noise variable model. The calculation expression of the random noise variable model is as follows:

[0042] y(t)=x(t)+n(t)

[0043] Where y(t) is the received communication signal, x(t) is the original communication signal, n(t) is the noise signal, and t is the time sequence;

[0044] The transient interference unit limits the transient amplitude by clamping the voltage through the transient interference model. The calculation expression of the transient interference model is as follows:

[0045]

[0046] Where A is the communication signal interference amplitude, t0 is the interference start time, t is the timing, rect() is the rectangular pulse function, τ is the interference duration, and i(t) is the pulse signal.

[0047] As a preferred solution of a distribution network communication signal protection system of the present invention, wherein:

[0048] The voltage clamping feedback unit is used to feed back the maximum clamping voltage of the power distribution network communication signal protection system. If the communication signal voltage exceeds the maximum clamping voltage, it is fed back to the voltage clamping module, and the voltage is adjusted by the voltage clamping module to maintain the communication signal within the set voltage range;

[0049] The filter feedback unit is used to feed back the communication signal processed by the filter unit, and determine whether oscillation and overshoot occur in the communication signal. If oscillation and overshoot occur, the filtered communication signal is fed back to the filter unit as a feedback signal, and the cutoff frequency of the filter unit is adjusted. If oscillation and overshoot do not occur, the communication signal is output.

[0050] As a preferred solution of a distribution network communication signal protection system of the present invention, wherein:

[0051] A tuning module is used to adjust the communication signal detection model.

[0052] The tuning module includes parameter adjustment, performance evaluation, feedback mechanism and model verification;

[0053] The parameter adjustment is used to optimize the communication signal interference amplitude and the temperature drift coefficient of the maximum clamping voltage of the transient interference model;

[0054] By calculating the communication signal interference amplitude gradient, adjusting the communication signal interference amplitude along the gradient direction to optimize the transient interference model with the minimum value, the transient interference model is continuously optimized;

[0055] The performance evaluation is used to evaluate how the transient interference model and the maximum clamping voltage behave in real applications.

[0056] The feedback mechanism is used to receive the feedback signal output by the feedback module.

[0057] As a preferred solution of a distribution network communication signal protection system of the present invention, wherein:

[0058] Beneficial effects of the present invention:

[0059] The present invention limits the maximum current in the circuit through the first resistor to prevent the circuit from being burned due to excessive current; and provides a voltage clamping module so that the communication signal is not greatly affected by temperature.

[0060] The communication signal detection algorithm is simple, with low investment cost, convenient later maintenance and upgrade, strong noise filtering, effectively ensuring the integrity of the signal, and strong signal error repairability. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0062] Figure 1 A system composition diagram of a communication signal protection system for a distribution network according to the present invention;

[0063] Figure 2 The present invention provides a clamping circuit diagram of a communication signal protection system for a distribution network. DETAILED DESCRIPTION

[0064] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0065] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0066] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0067] Embodiment 1:

[0068] like Figure 1 As shown, a distribution network communication signal protection system comprises:

[0069] The clamping circuit includes a first Zener diode, a second Zener diode, a third Zener diode, a fourth Zener diode, a fifth Zener diode, a first resistor, a triode, and a second resistor;

[0070] The first Zener diode is Figure 2 in DZENER1;

[0071] The second Zener diode is Figure 2 MediumDZENER2;

[0072] The third Zener diode is Figure 2 in DZENER3;

[0073] The fourth Zener diode is Figure 2 in DZENER4;

[0074] The fifth Zener diode is Figure 2 MediumDZENER5;

[0075] The first resistor is Figure 2 R in;

[0076] The second resistor is Figure 2 R1 in

[0077] The third resistor is Figure 2 R2 in

[0078] One end of the first Zener diode is connected to the collector of the transistor, and the other end is connected to the second Zener diode;

[0079] The other end of the second Zener diode is connected to one end of the third Zener diode;

[0080] The other end of the third Zener diode is connected to one end of the fourth Zener diode;

[0081] The other end of the fourth Zener diode is connected to one end of the fifth Zener diode;

[0082] The other end of the fifth Zener diode is connected to the base of the transistor and is connected in parallel with the first resistor;

[0083] The emitter of the transistor is connected to the second resistor;

[0084] The first resistor, the second resistor and the third resistor are zero-temperature resistors;

[0085] The resistance ratio of the second resistor to the third resistor is 1:n

[0086] The current source circuit includes a first MOS tube, a second MOS tube, a third MOS tube, a fourth MOS tube, a fifth MOS tube and a third resistor;

[0087] The first MOS tube is Figure 2 M1 in

[0088] The second MOS tube is Figure 2 M2 in;

[0089] The third MOS tube is Figure 2 M3 in;

[0090] The fourth MOS tube is Figure 2 M4 in;

[0091] The fifth MOS tube is Figure 2 M5 in;

[0092] The current source circuit generates a positive temperature coefficient current, and the positive temperature coefficient current is input into the second resistor;

[0093] The positive temperature coefficient current is Figure 2 I in;

[0094] The first MOS tube, the second MOS tube and the third MOS tube are P-type MOS tubes;

[0095] The fourth MOS tube and the fifth MOS tube are N-type MOS tubes;

[0096] The source of the first MOS tube is connected to the collector of the triode, the drain of the first MOS tube is connected to the second resistor, and the gate of the first MOS tube is connected to the gate of the second MOS tube;

[0097] The source of the second MOS tube is connected to the collector of the triode, the drain of the second MOS tube is connected to the source of the fourth MOS tube, and the gate of the second MOS tube is connected to the gate of the third MOS tube;

[0098] The source terminal of the third MOS tube is connected to the source of the second MOS tube, and the drain terminal of the third MOS tube is connected to the drain of the fifth MOS tube;

[0099] The source of the fourth MOS tube is connected to the other terminal of the second resistor, and the gate of the fourth MOS tube is connected to the gate of the fifth MOS tube;

[0100] The source of the fifth MOS tube is connected to one end of the third resistor, and the other end of the third resistor is connected to the source of the fourth MOS tube;

[0101] The ratio of the fourth MOS tube to the fifth MOS tube is 1:m;

[0102] The first Zener diode, the first MOS tube source, the second MOS tube source, the third MOS tube source and the transistor collector are all connected to a power supply.

[0103] The Zener breakdown voltages of the first Zener diode, the second Zener diode, the third Zener diode, the fourth Zener diode, and the fifth Zener diode and the base-emitter voltage of the transistor all have negative temperature coefficients.

[0104] Furthermore, the working principle is that the MOS tubes M1-M5 and the resistor R2 are a current source circuit, generating a current I with a positive temperature coefficient to supply the resistor R1, the ratio of the resistors R1 and R2 is 1:n, and the ratio of the NMOS tubes M4 and M5 is 1:m; the VCC voltage gradually rises, and when the VCC voltage reaches 27.5V, the Zener diodes 1-5 are turned on, forming a current path with the resistor R, and the voltage at point A gradually rises; when the voltage at point A rises so that the base-emitter voltage VBE of the transistor Q1 is greater than the threshold voltage, the transistor Q1 is turned on, and a large amount of current is discharged through the transistor, thereby controlling the VCC voltage;

[0105] When transistor Q1 is just turned on, VCC_CLAMP=5VD+VBE+IR1, where VD is the Zener breakdown voltage of the Zener diode, VBE is the base-emitter voltage of the transistor, and I is the positive temperature coefficient current.

[0106] Since the Zener breakdown voltage VD of the Zener diode and the base-emitter voltage VBE of the transistor are both negative temperature coefficients, and the current I is a positive temperature coefficient, VCC_CLAMP is not greatly affected by temperature, and the resistor R1 limits the circuit current to prevent excessive current from burning the circuit.

[0107] Embodiment 2:

[0108] A detection module, comprising a communication signal detection unit and a voltage detection unit, wherein the communication signal detection unit is used to extract communication information, and the voltage detection unit is used to monitor and measure the voltage of the communication signal protection system of the distribution network;

[0109] Among them, the detection module is used to detect the frequency of the communication signal, the interference time of the communication signal, the voltage of the communication signal and the noise signal;

[0110] The communication signal detection unit is used to extract useful communication information from the received signal and distinguish between the signal and noise and interference, including signal extraction, demodulation, decision decoding and performance evaluation;

[0111] The voltage detection unit is used to monitor and measure the voltage of the communication signal in the communication signal protection system of the distribution network.

[0112] The feedback module includes a voltage clamping feedback unit and a filtering feedback unit, wherein the voltage clamping feedback unit is used to feed back the maximum clamping voltage of the distribution network communication signal protection system, and the voltage clamping feedback unit is used to feed back the maximum clamping voltage of the distribution network communication signal protection system;

[0113] The voltage clamping feedback unit is used to feedback the maximum clamping voltage of the distribution network communication signal protection system. If the communication signal voltage exceeds the maximum clamping voltage, it is fed back to the voltage clamping module, and the voltage is adjusted by the voltage clamping module to maintain the communication signal within the set voltage range, ensuring signal stability, protecting circuits or equipment from damage, and ensuring stable operation of the system;

[0114] The filter feedback unit is used to feed back the communication signal processed by the filter unit, and determine whether the communication signal oscillates and overshoots. If oscillation and overshoot occur, the filtered communication signal is fed back to the filter unit as a feedback signal, and the cutoff frequency of the filter unit is adjusted. If oscillation and overshoot do not occur, the communication signal is output to eliminate or reduce noise and interference in the signal, improve system stability and signal quality, improve the system's response to changes, and reduce oscillation and overshoot.

[0115] A tuning module is used to adjust the communication signal detection model.

[0116] Among them, the tuning module includes parameter adjustment, performance evaluation, feedback mechanism and model verification;

[0117] Parameter adjustment is used to optimize the communication signal interference amplitude and temperature drift coefficient of the maximum clamping voltage of the transient interference model;

[0118] By calculating the communication signal interference amplitude gradient, adjusting the communication signal interference amplitude along the gradient direction to optimize the transient interference model with the minimum value, the transient interference model is continuously optimized;

[0119] Performance evaluation is used to evaluate the performance of transient interference models and maximum clamping voltage in actual applications to verify and improve the accuracy and robustness of the model;

[0120] The feedback mechanism is used to receive the feedback signal output by the feedback module;

[0121] Model validation is used to ensure that the tuned model meets the expected performance standards and can operate stably in real applications.

[0122] Embodiment 2:

[0123] The signal processing module includes a filter unit, a noise unit and a transient interference unit, wherein the filter unit is used to filter interference signals of communication signals, the noise unit is used to process noise of communication signals, and the transient interference unit is used to establish a transient interference model to limit transient amplitude;

[0124] The filter unit is used to filter high-frequency noise and interference in the communication signal to ensure the stability and clarity of the signal. It usually uses low-pass, high-pass, band-pass or band-stop filters to optimize signal quality;

[0125] The filter unit is a bandpass filter, which blocks signals of other frequencies and filters high-frequency noise and interference in communication signals. The calculation table is as follows:

[0126]

[0127] Where H(f) is the communication signal frequency allowed to pass by the bandpass filter, f is the input communication signal frequency, and f c is the high frequency cutoff frequency of the bandpass filter, f b is the low frequency cutoff frequency of the bandpass filter;

[0128] The noise unit is used to process random noise in the signal, such as electromagnetic interference or environmental noise. The noise suppression technology, such as adaptive filtering or noise elimination algorithm, can be used to reduce the impact on the signal.

[0129] The filter unit is a bandpass filter, which blocks signals of other frequencies and filters high-frequency noise and interference in communication signals. The calculation table is as follows:

[0130]

[0131] Where H(f) is the communication signal frequency allowed to pass by the bandpass filter, f is the input communication signal frequency, and f c is the high frequency cutoff frequency of the bandpass filter, f b is the low frequency cutoff frequency of the bandpass filter;

[0132] The transient interference unit is used to deal with short-term high-amplitude interference signals, such as shocks caused by lightning strikes or switching operations. It protects communication signals from transient interference through transient suppression technologies such as clamping circuits or filters.

[0133] The transient interference unit limits the transient amplitude by clamping the voltage through the transient interference model. The calculation expression of the transient interference model is as follows:

[0134]

[0135] Where A is the communication signal interference amplitude, t 0 is the interference start time, t is the timing, rect() is the rectangular pulse function, τ is the interference duration, and i(t) is the pulse signal.

[0136] It is important to note that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only two embodiments are described in detail in this disclosure, it should be easily understood by the personnel referring to this disclosure that many modifications are possible, for example, the size, scale, structure, shape and ratio of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc., without departing substantially from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method step can be changed or reordered according to the alternative embodiment. Any "device plus function" clause is intended to cover the structure of the execution function described in this article, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiment. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0137] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0138] It should be understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but for those of ordinary skill having the benefit of this disclosure, the development effort will be a routine task of design, fabrication, and production without undue experimentation.

[0139] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A distribution network communication signal protection system, comprising: A voltage clamp module, used to prevent the communication signal from exceeding a predetermined voltage range; A signal processing module, comprising a filtering unit, a noise unit and a transient interference unit, wherein the filtering unit is used to filter interference signals of communication signals, the noise unit is used to process noise of communication signals, and the transient interference unit is used to establish a transient interference model to limit transient amplitude; A detection module, comprising a communication signal detection unit and a voltage detection unit, wherein the communication signal detection unit is used to extract communication information, and the voltage detection unit is used to monitor and measure the voltage of the communication signal protection system of the distribution network; The feedback module includes a voltage clamping feedback unit and a filtering feedback unit, wherein the voltage clamping feedback unit is used to feed back the maximum clamping voltage of the distribution network communication signal protection system, and the voltage clamping feedback unit is used to feed back the maximum clamping voltage of the distribution network communication signal protection system; A tuning module is used to adjust the communication signal detection model.

2. A distribution network communication signal protection system according to claim 1, characterized in that: The voltage clamping module includes a clamping circuit and a power supply circuit; The clamping circuit includes a first Zener diode, a second Zener diode, a third Zener diode, a fourth Zener diode, a fifth Zener diode, a first resistor, a triode, and a second resistor; The current source circuit includes a first MOS tube, a second MOS tube, a third MOS tube, a fourth MOS tube, a fifth MOS tube and a third resistor; The first Zener diode, the first MOS tube source, the second MOS tube source, the third MOS tube source and the transistor collector are all connected to a power supply; The Zener breakdown voltages of the first Zener diode, the second Zener diode, the third Zener diode, the fourth Zener diode, and the fifth Zener diode and the base-emitter voltage of the transistor all have negative temperature coefficients.

3. A distribution network communication signal protection system according to claim 1, characterized in that: The maximum clamping voltage of the communication signal of the distribution network is calculated, and then the maximum voltage of the communication signal is monitored. The communication signal is optimized by the voltage clamping module. The maximum clamping voltage calculation expression is as follows: V max =V1×[1+T C ×(T X -z)]×(1+t); Among them, V max is the maximum clamping voltage of the distribution network communication signal protection system, V1 is the rated voltage of the Zener diode, T C is the temperature drift coefficient, T X is the actual operating temperature of the transistor, z is the room temperature, and t is the voltage difference of the clamping voltage.

4. A distribution network communication signal protection system according to claim 3, characterized in that: The filtering unit is used to filter high-frequency noise and interference in the communication signal; The noise unit is used to process random noise in the signal; The transient interference unit is used to deal with short-term high-amplitude interference signals.

5. A distribution network communication signal protection system according to claim 4, characterized in that: The filtering unit is a bandpass filter, which blocks signals of other frequencies and filters high-frequency noise and interference in the communication signal. The calculation table is as follows Where H(f) is the communication signal frequency allowed to pass by the bandpass filter, f is the input communication signal frequency, and f c is the high frequency cutoff frequency of the bandpass filter, f b is the low frequency cutoff frequency of the bandpass filter; The noise unit is used to process additive noise. The noise is processed by establishing a random noise variable model. The calculation expression of the random noise variable model is as follows: y(t)=x(t)+n(t) Where y(t) is the received communication signal, x(t) is the original communication signal, n(t) is the noise signal, and t is the time sequence; The transient interference unit limits the transient amplitude by clamping the voltage through the transient interference model. The calculation expression of the transient interference model is as follows: Among them, A is the interference amplitude of the communication signal, t0 is the start time of interference, t is the timing, rect() is the rectangular pulse function, τ is the interference duration, and i(t) is the pulse signal.

6. A distribution network communication signal protection system according to claim 5, characterized in that: The detection module is used to detect the frequency of the communication signal, the interference time of the communication signal, the voltage of the communication signal and the noise signal; The communication signal detection unit is used to extract useful communication information from the received signal and distinguish between the signal and noise and interference, including signal extraction, demodulation, decision decoding and performance evaluation; The voltage detection unit is used to monitor and measure the voltage of the communication signal in the communication signal protection system of the distribution network.

7. A distribution network communication signal protection system according to claim 6, characterized in that: The voltage clamping feedback unit is used to feed back the maximum clamping voltage of the power distribution network communication signal protection system. If the communication signal voltage exceeds the maximum clamping voltage, it is fed back to the voltage clamping module, and the voltage is adjusted by the voltage clamping module; The filter feedback unit is used to feed back the communication signal processed by the filter unit, and determine whether oscillation and overshoot occur in the communication signal. If oscillation and overshoot occur, the filtered communication signal is fed back to the filter unit as a feedback signal, and the cutoff frequency of the filter unit is adjusted. If oscillation and overshoot do not occur, the communication signal is output.

8. A distribution network communication signal protection system according to claim 7, characterized in that: The tuning module includes parameter adjustment, performance evaluation, feedback mechanism and model verification; The parameter adjustment is used to optimize the communication signal interference amplitude and the temperature drift coefficient of the maximum clamping voltage of the transient interference model; By calculating the communication signal interference amplitude gradient, adjusting the communication signal interference amplitude along the gradient direction to optimize the transient interference model with the minimum value, the transient interference model is continuously optimized; The performance evaluation is used to evaluate the performance of the transient interference model and the maximum clamping voltage in practical applications; The feedback mechanism is used to receive the feedback signal output by the feedback module.

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