Transformer area user transformer relation identification signal transmission method and computer program product

Abstract

The invention discloses a transformer area user transformer relation identification signal transmission method and a computer program product. The method comprises the steps that a sending end sends a pulse control signal on a power distribution line, so that the power distribution line generates pulse current; a zero-crossing detection circuit of the receiving end detects a power frequency voltage zero-crossing point; if the pulse current exists in the preset range where the power frequency voltage zero crossing point is located, the power distribution line superposes the pulse current on the load current of the power distribution line, so that the waveform of the power grid voltage of the power distribution line is distorted, and the position of the zero crossing point is slightly changed; the sending end carries out PPM modulation on the pulse current signal superposed on the load current, and obtains and sends a modulation signal; and the receiving end receives the modulation signal and identifies the transformer area to which the receiving end belongs based on the modulation signal. According to the method, the power frequency zero-crossing modulation is combined with the PPM modulation, so that the obtained modulation signal has very strong transformer area coverage, the current signal is not easy to cross the transformer area, and the hardware cost does not need to be increased.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a method for transmitting a transformer-substation-household-transformer relationship identification signal and a computer program product. Background Art

[0002] The distribution transformer refers to the distribution transformer. Commonly used household transformer relationship identification schemes include the following three:

[0003] 1. A method based on power outages in power distribution areas. This method uses a test power distribution area to identify users without power outages, assuming that surrounding power distribution areas are not experiencing outages. Users experiencing power outages belong to this power distribution area, while users experiencing power outages do not. However, while this method is highly accurate, it affects residential electricity consumption and requires manual investigation, making it unsuitable for large-scale deployment.

[0004] 2. An identification method based on the similarity of characteristic information of substations such as voltage and period. This method collects information such as voltage and period from both the transformer and user ends and calculates the similarity of the data. If the similarity is high, it means that the user belongs to the current substation; otherwise, the user does not belong to the current substation.

[0005] Third, handheld station identification devices, as handheld devices, use power frequency carrier modulation technology for communication. Multiple devices, when used in pairs, can accurately identify a user's phase and station affiliation. However, these handheld station identification devices are handheld test devices and cannot be installed in the field for long periods of time. They cannot automatically identify all users in a station area and cannot automatically transmit results to a master station for electricity consumption data collection. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for transmitting a transformer area household change relationship identification signal and a computer program product to solve the technical problems in the prior art.

[0007] The various technical effects that can be produced by the optional technical solutions among the various technical solutions provided by the present invention are described in detail below.

[0008] To achieve the above objectives, the present invention provides the following technical solutions:

[0009] In a first aspect, the present application provides a method for transmitting a transformer-to-substation relationship identification signal, which is applied to a power system, wherein the power system includes a transmitting end and a receiving end, wherein the transmitting end and the receiving end are respectively connected to a power distribution line; the transmission method includes:

[0010] The transmitting end transmits a pulse control signal on the power distribution line; wherein the transmitting end is provided with a thyristor, and when the thyristor is turned on, the power distribution line generates a pulse current;

[0011] The zero-crossing detection circuit at the receiving end detects the zero-crossing point of the power frequency voltage of the power distribution line, and detects whether the pulse current exists within a preset range of the zero-crossing point of the power frequency voltage;

[0012] If the pulse current exists, the power distribution line superimposes the pulse current on the load current of the power distribution line, so as to distort the waveform of the grid voltage of the power distribution line, resulting in a change in the position of the zero-crossing point;

[0013] The transmitting end performs PPM modulation on the pulse current signal superimposed on the load current to obtain and transmit a modulated signal;

[0014] The receiving end receives the modulated signal and identifies the station area to which the receiving end belongs based on the modulated signal.

[0015] In some embodiments, the transmitting end performs PPM modulation on the pulse current signal superimposed on the load current to obtain and transmit the modulated signal, including:

[0016] Determining a preset number of alternating current cycles based on a four-bit binary coding rule;

[0017] Combining the fixed offset Dt and a preset number of AC power cycles into a time slot group, and dividing the preset number of AC power cycles excluding the fixed offset Dt into a preset number of time slots to obtain a preset number of time slot numbers;

[0018] When the transmitting end sends a starting pulse current signal, it starts counting the time slot group, and after the fixed offset, it sends the next pulse current signal to complete the sending of the modulation signal corresponding to a group of time slot numbers.

[0019] In some embodiments, the receiving end receives the modulated signal and identifies the station area to which the receiving end belongs based on the modulated signal, including:

[0020] The receiving end determines whether there is a power frequency zero-crossing modulation signal in the zero-crossing signal output by the zero-crossing detection circuit;

[0021] If there is a power frequency zero-crossing modulation signal in the zero-crossing signal, determining the time slot number corresponding to the power frequency zero-crossing modulation signal;

[0022] Decoding is performed based on the time slot numbers corresponding to the multiple groups of the power frequency zero-crossing modulation signals, and the substation identification information is output to identify the substation household transformer relationship.

[0023] In some embodiments, the receiving end determines whether there is a power frequency zero-crossing modulation signal in the zero-crossing signal output by the zero-crossing detection circuit, including:

[0024] The receiving end demodulates the modulated signal to obtain a zero-crossing signal output by the zero-crossing detection circuit;

[0025] Determining a power frequency period value based on the zero-crossing signal;

[0026] The receiving end calculates the difference between the current power frequency cycle value and the power frequency cycle value of the previous cycle;

[0027] If the absolute value of the difference is less than a threshold, it is determined that the modulation signal does not contain the power frequency zero-crossing modulation signal;

[0028] If the absolute value of the difference is greater than the threshold, it is determined that the modulation signal contains the power frequency zero-crossing modulation signal.

[0029] In some embodiments, determining the power frequency period value based on the zero-crossing signal includes:

[0030] The power frequency period value is determined based on a time difference between two adjacent zero-crossing signals.

[0031] In some embodiments, after the receiving end receives the modulated signal and identifies the station area-user change relationship based on the modulated signal, the method further includes:

[0032] The receiving end outputs a signal-to-noise ratio when demodulating the modulated signal;

[0033] The signal quality of the current demodulated signal is determined according to the signal-to-noise ratio.

[0034] In some embodiments, the signal-to-noise ratio is calculated using the following formula:

[0035] SNR = |maximum peak value| / |average fluctuation value of AC power cycle|;

[0036] Wherein, SNR represents signal-to-noise ratio, and maximum peak represents the peak value when the power frequency zero-crossing modulation signal exists.

[0037] In some embodiments, the frame structure of the power frequency zero-crossing modulation signal includes a preamble, an identification code, a concentrator address, a phase, a clear flag, and a check code.

[0038] In some embodiments, when the grid voltage of the power distribution line is 0, the thyristor is automatically turned off.

[0039] In a second aspect, the present application also provides a method for transmitting a substation household change relationship identification signal, wherein the computer program product is stored on a data carrier and is designed to execute the method for transmitting a substation household change relationship identification signal according to any one of the first aspects.

[0040] Implementing one of the above technical solutions of the present invention has the following advantages or beneficial effects:

[0041] The transmission method and computer program product of the substation-to-substation relationship identification signal of the present application generates a pulse current in the power distribution line by turning on the thyristor, and superimposes the pulse current on the load current through the power distribution line, causing the waveform of the grid voltage to be distorted, resulting in a change in the zero-crossing point, and then performing PPM modulation on the pulse current signal superimposed on the load current. By combining power frequency zero-crossing modulation with PPM modulation, the obtained modulation signal has strong substation coverage, and the current signal is not easy to cross substations. When using this modulation signal for substation relationship identification, it has high accuracy; the use of PPM modulation reduces the heat generation of the power system and improves the safety of the power system.

[0042] Furthermore, the receiving end can utilize the high-precision zero-crossing detection circuit inherent in the on-site HPLC meter communication module, eliminating the need for additional hardware costs and requiring only a software upgrade to identify household-to-transformer relationship identification signals. Using existing hardware devices such as CCO and STA, the identification of household-to-transformer relationships within a substation improves the success rate of on-site household-to-transformer relationship and phase identification. Suitable for applications with chaotic household-to-transformer relationships within a substation, in conjunction with the on-site HPLC meter communication module, it accurately identifies a user's substation affiliation, providing data support for substation file organization, improving meter reading success rates, calculating line losses within a substation, managing load within a substation, and addressing three-phase imbalance. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] 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. Those skilled in the art can also derive other drawings based on these drawings without inventive work. In the drawings:

[0044] Figure 1 Schematic diagram of a method for transmitting a station area household change relationship identification signal according to an embodiment of the present application;

[0045] Figure 2 This is a circuit schematic diagram of a household change relationship identification signal transmitting end according to an embodiment of the present application;

[0046] Figure 3 1 is a circuit schematic diagram of a zero-crossing detection circuit at a receiving end of an embodiment of the present application;

[0047] Figure 4 This is a waveform diagram of a modulation signal according to an embodiment of the present application;

[0048] Figure 5 This is a timing diagram of the modulation signal of an embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to make the objects, technical solutions and advantages of the present invention clearer, the various exemplary embodiments to be described below will refer to the corresponding drawings, which constitute a part of the exemplary embodiments, in which various exemplary embodiments that may be used to implement the present invention are described. Unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation methods described in the following exemplary embodiments do not represent all implementation methods consistent with the present disclosure. It should be understood that they are only examples of processes, methods and devices that are consistent with some aspects of the present disclosure as detailed in the appended claims, and other embodiments may also be used, or structural and functional modifications may be made to the embodiments listed herein without departing from the scope and essence of the present invention.

[0050] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", etc. indicate the orientation or position relationship based on the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the elements referred to must have a specific orientation, be constructed and operate in a specific orientation. The terms "first", "second", etc. are only used for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. The term "plurality" means two or more. The terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, an integral connection, a mechanical connection, an electrical connection, a communication connection, a direct connection, an indirect connection through an intermediate medium, and can be the internal connection of two elements or the interaction relationship between two elements. The term "and / or" includes any and all combinations of one or more related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0051] In order to illustrate the technical solution of the present invention, a specific embodiment is provided below, in which only the parts related to the embodiment of the present invention are shown.

[0052] Example 1:

[0053] like Figure 1 As shown, the present application provides a method for transmitting a substation-to-substation relationship identification signal, which is applied to a power system. The power system includes a transmitting end and a receiving end, and the transmitting end and the receiving end are respectively connected to a power distribution line. The transmission method includes steps S100 to S500.

[0054] S100. The transmitting end transmits a pulse control signal on the power distribution line; wherein the transmitting end is provided with a thyristor, and when the thyristor is turned on, the power distribution line generates a pulse current.

[0055] Specifically, the substation-to-household relationship refers to the connection between distribution transformers (often referred to as substations) and the end users (households) they supply in a power system. In a power system, each distribution transformer is responsible for supplying power to a certain number of end users, which may be households within a residential complex, one or more buildings, or commercial users.

[0056] In the power system, a transmitting end is provided at one end of the power distribution line, and the transmitting end is provided with a thyristor; a receiving end is provided at the other end of the power distribution line, and the receiving end is provided with a zero-crossing detection circuit.

[0057] The sending end can be a Subscriber Terminal Adapter (STA), which is usually located at the user side and is responsible for encoding and modulating the data collected from user devices (such as smart meters, home automation devices, etc.) and then sending it out through the power distribution line.

[0058] The receiving end can be a CCO (Central Control Office). In a dual-mode communication system, the CCO is a central control unit responsible for managing and coordinating the entire communication network. Typically located at the power company, it receives data signals from user-side STAs, demodulates the received analog signals to restore them to their original data, and performs data management and processing. The CCO typically includes functions such as data processing, signal modulation and demodulation, and network monitoring and control. In a power system, the CCO can be a centralized communication center that communicates with various substations or substations via a dual-mode communication network, collecting data, monitoring grid status, and sending control commands to STAs (such as data transmission requests and system configuration updates).

[0059] Therefore, data transmission and interaction can be performed between STA and CCO via the power distribution line.

[0060] When transmitting the identification signal of the household change relationship in the area, such as Figure 2 As shown, Figure 2This is a schematic diagram of the signal transmission principle for identifying the relationship between the transformer and the substation. The VL and VN of the power distribution line are respectively connected to the two ends of the adjustable resistor RV100, one end of the adjustable resistor RV100 is connected to one end of the inductor L103, the other end of the inductor L103 is connected to one end of the resistor R120, one end of the adjustable resistor RV101 and the main terminal T1 of the bidirectional thyristor D114, the other end of the resistor R120 is connected to the positive electrode of the capacitor C118, the negative electrode of the capacitor C118, the other end of the adjustable resistor RV100, the other end of the adjustable resistor RV101, the main terminal T2 of the bidirectional thyristor D114, the other end of the capacitor C118, the other end of the resistor R125, the cathode of the diode D118 and the first end of the transformer T101 are all connected to the VN of the power distribution line, the control electrode G of the bidirectional thyristor D114 is connected to one end of the capacitor C120, one end of the resistor R124, and the resistor R125. The other end of the resistor R152 is connected to the other end of the resistor R152 and the anode of the diode D116. The cathode of the diode D116 is connected to the second end of the transformer T and the anode of the diode D118. The third end of the transformer T101 is connected to one end of the resistor R128 and the collector c of the transistor Q104. The fifth end of the transformer T101 is connected to the cathode of the diode D117, one end of the resistor R131, and one end of the capacitor C121. The other end of the capacitor C4 and the emitter e of the transistor Q104 are grounded. The other end of the resistor R128 is connected to the anode of the diode D117. The base b of the transistor Q104 is connected to one end of the resistor R130, one end of the resistor R132, and one end of the capacitor C172. The other end of the resistor R132 and the other end of the capacitor C172 are connected to the emitter e of the transistor Q104 and then to ground. The other end of the resistor R130 is used to input the pulse control signal PULSE.

[0061] When the STA, as the transmitter, sends a pulse control signal PULSE on the power distribution line, the thyristor at the transmitter opens, generating a pulse current between the VL (Line Voltage) and VN (Neutral Voltage) of the power distribution line. The CCO, as the receiver, monitors the signal on the power distribution line in real time.

[0062] In some embodiments, when the grid voltage of the power distribution line is 0, the thyristor is automatically turned off. Figure 2 As can be seen, PULSE is a pulse control signal, and the zero-crossing detection signal provides a time reference. The transmitter's timer sets the thyristor to reverse conduction for 9.6ms, and then controls the thyristor to forward conduction 10ms later. The thyristor automatically turns off when the voltage reaches 0V. The thyristor conducts within 400µs, pulling the power line voltage down to 0V. This creates a disturbance at the AC zero-crossing point, thereby transmitting a single-bit station identification pulse to the grid.

[0063] In some embodiments, VL is a power frequency voltage. During the modulation process, VL is the source of the carrier signal, and its zero crossing is used to trigger the generation of the pulse. VN can be used as a reference voltage during the modulation process to detect the zero crossing of VL.

[0064] In some embodiments, the transmitting end can be manually controlled to send a pulse control signal, thereby turning on the thyristor D114, causing the power distribution line to generate a pulse current.

[0065] In some embodiments, the transmitting end sends a pulse control signal. Since the current is relatively large during transmission and the thyristor generates severe heat, it cannot be sent continuously. In this case, the receiving end adopts PPM modulation.

[0066] S200. The zero-crossing detection circuit of the receiving end detects a zero-crossing point of the power frequency voltage of the power distribution line, and detects whether the pulse current exists within a preset range of the zero-crossing point of the power frequency voltage.

[0067] Specifically, the CCO as a receiving end has a zero-crossing detection circuit, such as Figure 3 As shown, Figure 3 : This is a schematic diagram of a zero-crossing detection circuit. The zero-crossing detection circuit is connected to the power frequency voltages VL and VN of the power distribution line. The VL of the power distribution line is connected to the anodes of resistors R137, R138 and diode D108 in sequence. The cathode of diode D108 is connected to one end of capacitor C125, one end of resistor R139, one end of capacitor C123, the cathode of Zener diode D109, and the first end of optocoupler U103. The other end of capacitor C125, the other end of resistor R139, the cathode of diode D110, and one end of resistor R140 are all connected to VN of the power distribution line. The other end of capacitor C123, the anode of Zener diode D109, the other end of capacitor C127, and the emitter of transistor Q106 are all connected to the cathode of diode D110. The anode, the other end of the resistor R140 is connected to one end of the capacitor C127 and the base of the transistor Q106, the collector of the transistor Q106 is connected to the second end of the optocoupler U103, the third end of the optocoupler U103 is connected to the +5V power supply and one end of the capacitor C124, and the other end of the capacitor C124 is grounded; the fourth end of the optocoupler U103 is connected to one end of the capacitor C126 and one end of the resistor R141, the other end of the capacitor C126 is grounded, the other end of the resistor R141 is connected to one end of the resistor R167, the other end of the resistor R167 is grounded, and the other end of the resistor R141 is used to output a periodic pulse signal ZERO-DET, for example, a pulse signal with an output period of 20ms, and each pulse rising edge indicates that the mains voltage drops through 0V.

[0068] The CCO, acting as the receiving end, monitors signals on the power distribution lines in real time. When the zero-crossing detection circuit detects the zero-crossing point of the power distribution line's power frequency voltage, it then checks for the presence of the pulse current within a preset range of that point. This eliminates the need for additional hardware costs. The HPLC meter communication module used on-site already has a highly accurate hardware zero-crossing detection circuit. Simply upgrading the software allows it to identify the transmitted household-to-transformer identification signal.

[0069] like Figure 4 As shown, Figure 4 In the calculation, dt represents the duration of the pulse current, for example, 100µs to 500µs. Based on the zero-crossing detection signal, the AC mains cycle variation can be determined. The preset zero-crossing range is ±(100µs to 500µs) from the zero-crossing point, meaning it occurs within a range of ±(100µs to 500µs) from the falling or rising edge of the zero-crossing point. Within this range, the presence of a pulse current is detected. If a pulse current is present, the preceding cycle will decrease, while the following cycle will increase.

[0070] exist Figure 4 In the embodiment, the fixed offset Dt is the time of 4 AC cycles, but it is certainly not limited to 4 AC cycles and can be adjusted according to actual conditions.

[0071] S300: If the pulse current exists, the power distribution line superimposes the pulse current on the load current of the power distribution line to distort the waveform of the grid voltage of the power distribution line, resulting in a change in the position of the zero-crossing point.

[0072] Specifically, if the receiving end detects a pulse current near the zero-crossing point of the power frequency voltage, it indicates that the thyristor Q1 on the transmitting end has turned on based on the pulse control signal PULSE. The power distribution line then superimposes the pulse current on the load current, distorting the grid voltage waveform. This subtle distortion in voltage and current can be used as a modulated signal to carry the desired information.

[0073] The broadcast frame for identifying the relationship between users can be sent using the industrial frequency zero-crossing modulation technology.

[0074] S400: The transmitting end performs PPM modulation on the pulse current signal superimposed on the load current to obtain and transmit a modulated signal.

[0075] In some implementations, step S400 may include:

[0076] Determining a preset number of alternating current cycles based on a four-bit binary coding rule;

[0077] Combining the fixed offset Dt and a preset number of AC power cycles into a time slot group, and dividing the preset number of AC power cycles excluding the fixed offset Dt into a preset number of time slots to obtain a preset number of time slot numbers;

[0078] When the transmitting end sends a starting pulse current signal, it starts counting the time slot group, and after the fixed offset, it sends the next pulse current signal to complete the sending of the modulation signal corresponding to a group of time slot numbers.

[0079] Specifically, PPM (Pulse Position Modulation) is a pulse position modulation method, the principle of which is to convert a digital signal into a pulse signal and achieve information transmission by changing the position of the pulse.

[0080] The four-bit binary encoding rule is to encode in units of 4 bits, and there are 16 cases from 0 to F. That is, the preset number is 16.

[0081] The fixed offset Dt may be 4 AC cycles, and may also be adjusted according to actual conditions, which is not limited here.

[0082] When the transmitter performs PPM modulation on the pulse current signal superimposed on the load current, it determines 16 AC cycles according to the four-bit binary coding rule, groups the fixed offset Dt + 16 AC cycles into a time slot group, and divides the 16 AC cycles excluding the fixed offset Dt into 16 time slots. Then, the time slot numbering starts from 0 and ends at 0xF.

[0083] When sending a pulse current signal, 4 bits of data are allocated to each of the 16 time slots, and the count is performed as the signal is sent. For example, when sending a start pulse current signal (data is 0), the pulse current signal is sent in time slot 0; when sending time slot 0xA, the pulse current signal is sent in time slot A. In other words, a start pulse current signal is sent in each frame, indicating that the time slot group count is about to begin.

[0084] like Figure 5 As shown, Figure 5 The timing diagram of the modulated signal is shown in Figure 2. If Dt is the duration of four AC cycles, then the period of each time slot group is 20*20ms=400ms, and each time slot group transmits 4 bits at a transmission rate of 10 bps.

[0085] S500: The receiving end receives the modulated signal, and identifies the station area to which the receiving end belongs based on the modulated signal.

[0086] In some implementations, step S500 may include:

[0087] The receiving end determines whether there is a power frequency zero-crossing modulation signal in the zero-crossing signal output by the zero-crossing detection circuit;

[0088] If there is a power frequency zero-crossing modulation signal in the zero-crossing signal, determining the time slot number corresponding to the power frequency zero-crossing modulation signal;

[0089] Decoding is performed based on the time slot numbers corresponding to the multiple groups of the power frequency zero-crossing modulation signals, and the substation identification information is output to identify the substation household transformer relationship.

[0090] Specifically, the signal reception can adopt the zero-crossing detection signal of the STA module to track the change of the power frequency cycle in real time.

[0091] In some embodiments, the receiving end determines whether there is a power frequency zero-crossing modulation signal in the zero-crossing signal output by the zero-crossing detection circuit, including:

[0092] The receiving end demodulates the modulated signal to obtain a zero-crossing signal output by the zero-crossing detection circuit;

[0093] Determining a power frequency period value based on the zero-crossing signal;

[0094] The receiving end calculates the difference between the current power frequency cycle value and the power frequency cycle value of the previous cycle;

[0095] If the absolute value of the difference is less than a threshold, it is determined that the modulation signal does not contain the power frequency zero-crossing modulation signal;

[0096] If the absolute value of the difference is greater than the threshold, it is determined that the modulation signal contains the power frequency zero-crossing modulation signal.

[0097] Specifically, in order to improve the anti-interference capability, digital differential technology can be used. Digital differential is to perform a difference operation between the previous cycle power frequency value and the current power frequency cycle value, which can be expressed by the following formula:

[0098] d(t)=T(n-1)-T(n);

[0099] Here, d(t) represents the difference between the current power frequency cycle value and the previous power frequency cycle value, T(n-1) represents the previous power frequency cycle value, and T(n) represents the current power frequency cycle value. The power frequency cycle value is the time difference between two adjacent power frequency zero-crossing signals. A power frequency zero-crossing signal refers to two points in time within a power frequency cycle where the power frequency voltage reaches zero. For example, if the STA's zero-crossing detection circuit outputs a pulse signal when the voltage drops through zero, this pulse signal is considered a power frequency zero-crossing signal.

[0100] If the absolute value of the difference d(t) is less than the threshold, for example, the threshold may be 0.5, which is close to 0, it indicates that the modulation signal does not contain the power frequency zero-crossing modulation signal; conversely, if the absolute value of the difference d(t) is greater than the threshold, it is determined that the modulation signal contains the power frequency zero-crossing modulation signal.

[0101] In some implementation methods, the frame structure of the power frequency zero-crossing modulation signal includes a preamble, an identification code, a concentrator address, a phase, a clear flag, and a check code.

[0102] The power frequency zero-crossing modulation signal is only used for station location in dual-mode, and has a low transmission rate. Based on the principles of efficiency and simplicity, the frame structure of the power frequency zero-crossing modulation signal includes a preamble, an identification code, a concentrator address, a phase, a clear flag, and a check code, as shown in Table 1 below:

[0103]

[0104] Table 1

[0105] The power frequency zero-crossing modulated signal is sent and received in 4-bit units, using the little-endian mode. For multi-byte data, the low byte is sent first, and then the high byte. That is, the low 4 bits of each byte are sent first, and then the high 4 bits.

[0106] In Table 1, the preamble and identification number bits are fixed data and are used to determine the start of the frame. The concentrator address is 6 bytes and is the same as the actual CCO address. Phase 00B indicates unknown, 01B indicates phase A, 10B indicates phase B, and 11B indicates phase C. The identification record clear flag indicates that when set, the STA needs to clear all user change relationship identification information and restart recording. This is usually used to clear the original user change relationship identification broadcast after the concentrator address changes. Checksum refers to calculating CRC8 starting from the concentrator address. By performing polynomial calculations on the address, control, and data fields, the integrity of the frame transmission is ensured.

[0107] In some embodiments, after the receiving end receives the modulated signal and identifies the station area-user change relationship based on the modulated signal, the method may further include:

[0108] The receiving end outputs a signal-to-noise ratio when demodulating the modulated signal;

[0109] The signal quality of the current demodulated signal is determined according to the signal-to-noise ratio.

[0110] Specifically, the signal-to-noise ratio is used to measure the quality of the current signal. When the receiver demodulates the modulated signal, it calculates the signal-to-noise ratio using the following formula:

[0111] SNR = |maximum peak value| / |average fluctuation value of AC power cycle|;

[0112] Wherein, SNR represents signal-to-noise ratio, and maximum peak represents the peak value when the power frequency zero-crossing modulation signal exists.

[0113] SNR can be represented by one byte. When it is greater than 255, it is set to 255. A larger SNR value indicates better signal quality, and a smaller SNR value indicates worse signal quality.

[0114] The transmission method of the transformer-to-electricity relationship identification signal of the present application generates a pulse current in the power distribution line by turning on the thyristor, and superimposes the pulse current on the load current through the power distribution line, so that the waveform of the grid voltage is distorted, resulting in a change in the zero-crossing point, and then PPM modulation is performed on the pulse current signal superimposed on the load current. By combining the power frequency zero-crossing modulation with PPM modulation, the obtained modulation signal has strong transformer coverage, and the current signal is not easy to cross the transformer area. When using this modulation signal for transformer-to-electricity relationship identification, it has high accuracy; the use of PPM modulation reduces the heat generation of the power system and improves the safety of the power system.

[0115] Furthermore, the receiving end can utilize the high-precision zero-crossing detection circuit inherent in the on-site HPLC meter communication module, eliminating the need for additional hardware costs and requiring only a software upgrade to identify household-to-transformer relationship identification signals. Using existing hardware devices such as CCO and STA, the identification of household-to-transformer relationships within a substation improves the success rate of on-site household-to-transformer relationship and phase identification. Suitable for applications with chaotic household-to-transformer relationships within a substation, in conjunction with the on-site HPLC meter communication module, it accurately identifies a user's substation affiliation, providing data support for substation file organization, improving meter reading success rates, calculating line losses within a substation, managing load within a substation, and addressing three-phase imbalance.

[0116] The embodiment is only a special case and does not indicate that the present application is implemented in such a way.

[0117] Those skilled in the art will appreciate that all or part of the features / steps of the above-mentioned method embodiments can be implemented by methods, data processing systems, or computer programs. These features can be implemented without hardware, entirely in software, or in a combination of hardware and software. The aforementioned computer program can be stored in one or more computer-readable storage media. The storage medium stores the computer program. When the computer program is executed (e.g., by a processor), the steps of the above-mentioned method embodiment for transmitting a substation-to-user relationship identification signal are executed.

[0118] The aforementioned storage media that can store program codes include: static hard disks, solid-state hard disks, random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), optical storage devices, magnetic storage devices, flash memory, magnetic disks or optical disks and / or combinations of the above devices, that is, they can be implemented by any type of volatile or non-volatile storage device or a combination thereof.

[0119] The present application also provides a computer program product stored on a data carrier and designed to execute the method for transmitting a station area user-to-user relationship identification signal as described above. Therefore, the computer program product according to the present application produces the same advantages as those described in detail with reference to the apparatus according to the present application. The computer program product can be executed as computer-readable instruction code in any suitable programming language, such as JAVA, C++, etc. Furthermore, the computer program product can be provided on a network, such as the Internet, or can be downloaded from a network, such as the Internet, by a user of the network, such as the Internet, when needed. The computer program product can be implemented using a computer program, i.e., software, or one or more dedicated electronic circuits, i.e., hardware, or in any hybrid form, i.e., using software components and hardware components, or in a hybrid form of software, hardware, or software and hardware.

[0120] The foregoing is merely a preferred embodiment of the present invention. Those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. Furthermore, under the guidance of the present invention, these features and embodiments may be modified to suit specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be within the scope of the present invention.

Claims

1. A method for transmitting a signal identifying a relationship between a transformer and a household in an area, applied to a power system, characterized in that: The power system includes a transmitting end and a receiving end, wherein the transmitting end and the receiving end are respectively connected to a power distribution line; The transmission method includes: The transmitting end transmits a pulse control signal on the power distribution line; wherein the transmitting end is provided with a thyristor, and when the thyristor is turned on, the power distribution line generates a pulse current; The zero-crossing detection circuit at the receiving end detects the zero-crossing point of the power frequency voltage of the power distribution line, and detects whether the pulse current exists within a preset range of the zero-crossing point of the power frequency voltage; If the pulse current exists, the power distribution line superimposes the pulse current on the load current of the power distribution line, so as to distort the waveform of the grid voltage of the power distribution line, resulting in a change in the position of the zero-crossing point; The transmitting end performs PPM modulation on the pulse current signal superimposed on the load current to obtain and transmit a modulated signal; The receiving end receives the modulated signal and identifies the station area to which the receiving end belongs based on the modulated signal.

2. The method for transmitting a station area household change relationship identification signal according to claim 1, characterized in that: The transmitting end performs PPM modulation on the pulse current signal superimposed on the load current to obtain and transmit a modulated signal, including: Determining a preset number of alternating current cycles based on a four-bit binary coding rule; Combining the fixed offset Dt and a preset number of AC power cycles into a time slot group, and dividing the preset number of AC power cycles excluding the fixed offset Dt into a preset number of time slots to obtain a preset number of time slot numbers; When the transmitting end sends a starting pulse current signal, it starts counting the time slot group, and after the fixed offset, it sends the next pulse current signal to complete the sending of the modulation signal corresponding to a group of time slot numbers.

3. The method for transmitting a station area household change relationship identification signal according to claim 1, characterized in that: The receiving end receives the modulated signal and identifies the station area to which the receiving end belongs based on the modulated signal, including: The receiving end determines whether there is a power frequency zero-crossing modulation signal in the zero-crossing signal output by the zero-crossing detection circuit; If there is a power frequency zero-crossing modulation signal in the zero-crossing signal, determining the time slot number corresponding to the power frequency zero-crossing modulation signal; Decoding is performed based on the time slot numbers corresponding to the multiple groups of the power frequency zero-crossing modulation signals, and the substation identification information is output to identify the substation household transformer relationship.

4. The method for transmitting a station area household change relationship identification signal according to claim 3, characterized in that: The receiving end determines whether there is a power frequency zero-crossing modulation signal in the zero-crossing signal output by the zero-crossing detection circuit, including: The receiving end demodulates the modulated signal to obtain a zero-crossing signal output by the zero-crossing detection circuit; Determining a power frequency period value based on the zero-crossing signal; The receiving end calculates the difference between the current power frequency cycle value and the power frequency cycle value of the previous cycle; If the absolute value of the difference is less than a threshold, it is determined that the modulation signal does not contain the power frequency zero-crossing modulation signal; If the absolute value of the difference is greater than the threshold, it is determined that the modulation signal contains the power frequency zero-crossing modulation signal.

5. The method for transmitting a station area household change relationship identification signal according to claim 1, characterized in that: The determining of the power frequency period value based on the zero-crossing signal includes: The power frequency period value is determined based on a time difference between two adjacent zero-crossing signals.

6. The method for transmitting a station area household change relationship identification signal according to claim 1, characterized in that: After the receiving end receives the modulated signal and identifies the station area-user change relationship based on the modulated signal, the method further includes: The receiving end outputs a signal-to-noise ratio when demodulating the modulated signal; The signal quality of the current demodulated signal is determined according to the signal-to-noise ratio.

7. The method for transmitting a station area household change relationship identification signal according to claim 6, characterized in that: The signal-to-noise ratio is calculated using the following formula: SNR = |maximum peak value| / |average fluctuation value of AC power cycle|; Wherein, SNR represents signal-to-noise ratio, and maximum peak represents the peak value when the power frequency zero-crossing modulation signal exists.

8. The method for transmitting a station area household change relationship identification signal according to claim 3, characterized in that: The frame structure of the power frequency zero-crossing modulation signal includes a preamble, an identification code, a concentrator address, a phase, a clear mark and a check code.

9. The method for transmitting a station area household change relationship identification signal according to claim 1, characterized in that: When the grid voltage of the power distribution line is 0, the thyristor is automatically turned off.

10. A computer program product, characterized in that The computer program product is stored on a data carrier and is designed to execute the method for transmitting a substation-to-household relationship identification signal according to any one of claims 1-9.

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