An automatic acquisition and compensation device and method for daily timing error of an electricity meter

Abstract

This invention relates to the technical field of electricity meter measurement, and mainly discloses an automatic acquisition and compensation device and method for daily timing errors of electricity meters. It includes an interface expansion device for connecting multiple electricity meters and a clock; and a compensation host computer electrically connected to the interface expansion device for controlling the interface expansion device and realizing error acquisition and compensation. A communication connection is established between the interface expansion device and the compensation host computer to transmit control signals and data. This invention solves the problem that traditional testing methods are cumbersome and complex in operation, requiring frequent disassembly and reconnection of various interfaces of the electricity meter when performing high and low temperature daily timing calibration.

Description

Technical Field

[0001] This invention relates to the technical field of electricity meter measurement, and in particular to an automatic acquisition and compensation device and method for daily timing error of electricity meters. Background Technology

[0002] In today's power systems, electricity meters, as key devices for measuring electrical energy, play a crucial role in ensuring the fairness and reliability of electricity metering due to their accuracy. With the continuous development of the power industry and the gradual advancement of smart grid construction, the requirements for the accuracy of electricity meter readings are becoming increasingly stringent.

[0003] Currently, existing methods for testing and calibrating daily timing errors in electricity meters have many problems. Traditional testing methods are cumbersome and complex to operate. When calibrating the daily timing of electricity meters for high and low temperatures, it is necessary to frequently disassemble and reconnect various interfaces of the electricity meter. Each calibration requires connecting the daily timing pulse signal output terminal of the electricity meter to a clock tester, the RS485 output terminal to a computer, and the power connection terminal to an external power source. This operation method not only consumes a lot of manpower and resources, but also makes the wiring process extremely inconvenient, resulting in low work efficiency. At the same time, the need to connect numerous wires can easily lead to messy wiring, increasing the risk of circuit faults and the difficulty of subsequent troubleshooting. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is that the traditional testing method is cumbersome and complicated in operation. When the electricity meter is calibrated for high and low temperature daily timing, it is necessary to frequently disassemble and connect the various interfaces of the electricity meter.

[0005] The above-mentioned technical problems are solved by the following technical solution: This invention proposes an automatic acquisition and compensation device for daily timing errors of electricity meters, which includes an interface expansion device for connecting multiple electricity meters and a clock; a compensation host computer electrically connected to the interface expansion device for controlling the interface expansion device and realizing error acquisition and compensation; wherein, a communication connection is established between the interface expansion device and the compensation host computer to transmit control signals and data.

[0006] In a preferred embodiment of the automatic acquisition and compensation device for daily timing error of the electricity meter described in this invention: the interface expansion device further includes a motherboard, on which are mounted a second pulse signal interface module, an analog switch, a 485 signal interface module, and a control module; the second pulse signal interface module connects to the second pulse signal of the electricity meter via a pin and a female connector structure, all negative terminals of the second pulse signal interface module are shorted and connected to a common ground terminal, and the positive terminal is electrically connected to the second pulse input terminal of the clock via the analog switch; the 485 signal interface module connects to the 485 signal of the electricity meter via a pin and a female connector structure, and the 485A and 485B terminals of the 485 signal interface module are electrically connected to the 485 communication interface of the compensation host computer via signal switching circuits; the control module is electrically connected to the analog switch and the signal switching circuit of the 485 signal interface module.

[0007] In a preferred embodiment of the automatic acquisition and compensation device for daily timing errors of the electricity meter described in this invention: the motherboard is further provided with a CPU simulation / programming download interface, which is electrically connected to the debugging interface of the control module for program burning and debugging; a digital tube, electrically connected to the control module through an I / O interface, configured to display the currently selected electricity meter position number; a running light and a pause light, respectively electrically connected to the status indicator output terminal of the control module through a drive circuit, configured to indicate the working status of the device; a reserved I / O interface, electrically connected to the general I / O port of the control module, for expanding external functional modules; a USB interface, electrically connected to the communication port of the control module through a USB to serial port chip, configured to realize data communication with the compensation host computer and power supply to the device; and a reset button, electrically connected to the reset pin of the control module, configured to trigger the device to reset.

[0008] In a preferred embodiment of the automatic acquisition and compensation device for daily timing error of the electricity meter described in this invention: the main board is further provided with an electricity meter 485 interface group, including multiple sets of first 485A contacts and first 485B contacts, each set of contacts being electrically connected to the corresponding channel of the 485 signal interface module through a protection circuit; an electricity meter multi-function interface group, including multiple sets of RTC+ contacts and RTC- contacts, each set of contacts being electrically connected to the corresponding channel of the second pulse signal interface module through a signal conditioning circuit; a daily timing instrument interface, including positive contacts and negative contacts, being electrically connected to the corresponding input terminal of the clock through an isolation circuit; and a PC RS485 interface, including third 485A contacts and fourth 485B contacts, being electrically connected to the 485 communication interface of the compensation host computer through an RS485 transceiver.

[0009] In a preferred embodiment of the automatic acquisition and compensation device for daily timing error of the electricity meter according to the present invention: the compensation host computer includes a clock connection module, an expansion device connection module, and an electricity meter connection module; the clock connection module is electrically connected to the communication interface of the clock via a communication bus; the expansion device connection module is electrically connected to the USB interface of the interface expansion device or the RS485 interface of the PC via a USB bus or an RS485 bus; the electricity meter connection module is electrically connected to the 485 communication interface of the electricity meter via the 485 signal interface module of the interface expansion device, and is configured to send read / write commands and receive electricity meter data.

[0010] In a preferred embodiment of the automatic acquisition and compensation device for daily timing errors of the electricity meter according to the present invention: the compensation host computer further includes a task processing module, which is communicatively connected to the clock connection module, the expansion device connection module, and the electricity meter connection module; the task processing module manages the meter position address mapping relationship and generates meter position selection instructions through the meter position processing unit; the task processing module sets the task execution parameters and error compensation strategy through the parameter configuration unit; the task processing module coordinates the execution of the task process of each module and stores the execution results through the scheme execution unit.

[0011] To address the aforementioned problems, this invention also proposes the following technical solution: an automatic acquisition and compensation method for daily timing errors of an electricity meter, comprising the following steps: establishing a physical connection between the electricity meter and an interface expansion device; establishing a communication connection between the interface expansion device and a compensation host computer and a clock, and initializing the system; selecting a target meter position and controlling an analog switch to switch channels, connecting the second pulse signal and 485 signal path of the target electricity meter; acquiring daily timing error data of the target electricity meter, filtering the data, comparing the filtered data with a preset threshold, and calculating a compensation value and writing it into the electricity meter if it exceeds the threshold; after completing the above operations for all selected meter positions in sequence, generating and storing a detailed report containing measurement data and compensation results for each meter position.

[0012] In a preferred embodiment of the automatic acquisition and compensation method for daily timing error of electricity meter described in this invention: before selecting the target meter position and switching channels, the compensation host computer reads the internal temperature sensor data of the electricity meter through the meter connection module to confirm that the temperature remains within the target temperature ±2℃ range for at least 15 minutes; when switching channels, the control module first disconnects all connected channels and then connects the channel of the target meter position.

[0013] In a preferred embodiment of the automatic acquisition and compensation method for daily timing error of the electricity meter described in this invention: when filtering the acquired daily timing error data, a moving average algorithm is used to filter at least three consecutively acquired data; the filtered error value is compared with the error threshold set by the parameter configuration unit; if the three consecutive measurements are all within the threshold range, the meter position is determined to be calibrated successfully; otherwise, a compensation value is calculated based on the average error value; the calculated compensation value is converted into an instruction conforming to the electricity meter communication protocol format and written into the time register of the electricity meter through the meter connection module.

[0014] In a preferred embodiment of the automatic acquisition and compensation method for daily timing error of electricity meters described in this invention: in any operation step, if a meter position experiences three consecutive communication timeouts or verification errors, the task processing module automatically marks the meter position as abnormal and skips the meter position to continue executing the tasks of subsequent meter positions; after all tasks are completed, the generated detailed report distinguishes between normal meter positions and abnormal meter positions, and provides a fault code and possible cause analysis for each abnormal meter position.

[0015] The beneficial effects of this invention are as follows:

[0016] 1. It realizes the automated collection and compensation of daily timing errors of electricity meters, reducing manual operation and improving work efficiency and accuracy.

[0017] 2. The multi-meter connection interface expansion device can connect multiple energy meters simultaneously, meeting the needs of large-scale testing and reducing debugging and calibration costs.

[0018] 3. The automation solution customization function can freely combine data acquisition and compensation schemes according to different situations, which improves the adaptability and flexibility of the tooling and effectively handles special situations. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein:

[0020] Figure 1 This diagram shows the structure of the automatic daily timing error acquisition and compensation device for electricity meters;

[0021] Figure 2 This diagram shows some structural schematics of the interface expansion device of the automatic acquisition and compensation device for daily timing error of electricity meter;

[0022] Figure 3 This diagram shows the remaining structure of the interface expansion device for the automatic acquisition and compensation device for daily timing errors of electricity meters;

[0023] Figure 4This diagram shows the structure of the compensation host computer for the automatic acquisition and compensation device for daily timing errors of electricity meters.

[0024] Figure 5 The flowchart illustrates the working principle of the automatic acquisition and compensation method for daily timing errors in electricity meters.

[0025] Figure 6 The flowchart illustrates the operation of the automatic acquisition and compensation method for daily timing errors of electricity meters. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0027] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0028] Example 1

[0029] Reference Figures 1-6 The first embodiment of the present invention provides an automatic acquisition and compensation device for daily timing error of electricity meters, which includes an interface expansion device 100 for connecting multiple electricity meters 101 and a clock 102.

[0030] The compensation host computer 200 is electrically connected to the interface expansion device 100 and is used to control the interface expansion device 100 and realize error acquisition and compensation.

[0031] The interface expansion device 100 establishes a communication connection with the compensation host computer 200 to transmit control signals and data.

[0032] Specifically, the interface expansion device 100 also includes a motherboard 103, which contains a second pulse signal interface module 103a, an analog switch 103b, a 485 signal interface module 103c, and a control module 103d.

[0033] The second pulse signal interface module 103a is connected to the second pulse signal of the energy meter 101 through the pin and the socket structure. All negative terminals of the second pulse signal interface module 103a are shorted and connected to the common ground terminal. The positive terminal is electrically connected to the second pulse input terminal of the clock 102 through the analog switch 103b.

[0034] The 485 signal interface module 103c is connected to the 485 signal of the energy meter 101 through a pin and socket structure. The 485A and 485B terminals of the 485 signal interface module 103c are electrically connected to the 485 communication interface of the compensation host computer 200 through signal switching circuits, respectively.

[0035] The control module 103d is electrically connected to the signal switching circuits of the analog switch 103b and the 485 signal interface module 103c, respectively.

[0036] The motherboard 103 is also equipped with a CPU emulation / programming download interface 103e, which is electrically connected to the debugging interface of the control module 103d for program burning and debugging.

[0037] The digital tube 103f is electrically connected to the control module 103d via an I / O interface and is configured to display the number of the currently selected energy meter position.

[0038] The running light 103g and the pause light 103h are electrically connected to the status indication output terminal of the control module 103d through the drive circuit, respectively, and are configured to indicate the working status of the device.

[0039] A reserved I / O interface 103k is provided for electrical connection to the general-purpose I / O port of the control module 103d, which is used to expand external functional modules.

[0040] The USB interface 103m is electrically connected to the communication port of the control module 103d via a USB-to-serial chip, and is configured to realize data communication with the compensation host computer 200 and power supply to the device.

[0041] The reset button 103n is electrically connected to the reset pin of the control module 103d and is configured to trigger the device to reset.

[0042] The motherboard 103 is also equipped with a 485 interface group 103p, which includes multiple sets of first 485A contacts 103p-1 and first 485B contacts 103p-2. Each set of contacts is electrically connected to the corresponding channel of the 485 signal interface module 103c through a protection circuit.

[0043] The multi-function interface group 103q of the electricity meter includes multiple RTC+ contacts 103q-1 and RTC- contacts 103q-2. Each group of contacts is electrically connected to the corresponding channel of the second pulse signal interface module 103a through a signal conditioning circuit.

[0044] The daytime clock interface 103r includes a positive contact 103r-1 and a negative contact 103r-2, which are electrically connected to the corresponding input terminals of the clock 102 through isolation circuits.

[0045] The PC RS485 interface 103s includes a third 485A contact 103s-1 and a fourth 485B contact 103s-2, which are electrically connected to the RS485 communication interface of the compensated host computer 200 through RS485 transceivers.

[0046] The compensation host computer 200 includes a clock connection module 201, an expansion device connection module 202, and an electricity meter connection module 203.

[0047] The clock connection module 201 is electrically connected to the communication interface of the clock 102 via a communication bus.

[0048] The expansion device connection module 202 is electrically connected to the USB interface 103m of the interface expansion device 100 or the RS485 interface 103s of the PC via a USB bus or RS485 bus.

[0049] The meter connection module 203 is electrically connected to the 485 communication interface of the energy meter 101 through the 485 signal interface module 103c of the interface expansion device 100, and is configured to send read and write commands and receive energy meter data.

[0050] The compensation host computer 200 also includes a task processing module 204, which is communicatively connected to the clock connection module 201, the expansion device connection module 202, and the electricity meter connection module 203.

[0051] The task processing module 204 manages the table address mapping relationship and generates table selection instructions through the table processing unit 204a.

[0052] The task processing module 204 sets the task execution parameters and error compensation strategy through the parameter configuration unit 204b.

[0053] The task processing module 204 coordinates the execution of the task process by each module and stores the execution results through the scheme execution unit 204c.

[0054] Specifically, during use, when the electricity meter 101 is connected to the meter 485 interface group 103p and the meter multi-function interface group 103q of the interface expansion device 100 through the pin socket, its second pulse signal RTC+ and RTC- enter the second pulse signal interface module 103a through the signal conditioning circuit.

[0055] The signal conditioning circuit includes an RC filter network to filter out high-frequency noise and ensure the purity of the input signal.

[0056] Furthermore, all RTC-contacts 103q-2 are shorted to a common ground terminal via PCB copper plating to form a low-impedance grounding loop to stabilize the reference potential. RTC+contacts 103q-1 are transmitted to the second pulse input terminal of the clock 102 through the gating channel of analog switch 103b. Analog switch 103b preferably uses SGM3157, which adopts a single-pole double-throw structure, has a low on-resistance of 4.5Ω and a high-speed switching characteristic of 20ns, supports a wide voltage input of 1.8V to 5.5V, and can work stably in a temperature range of -40℃ to 85℃, ensuring that the second pulse signal has no significant attenuation or distortion during transmission.

[0057] Current flows out from the RTC+ contact 103q-1 pin of the energy meter, passes through the gold-plated pin of the multi-function interface group 103q of the energy meter, the printed circuit board trace of the second pulse signal interface module 103a, and the conduction channel of the analog switch 103b, and finally forms a closed loop to the second pulse input terminal of the clock 102.

[0058] The 485 communication signals 485A and 485B in the electricity meter 101 first pass through the protection circuit of the 485 interface group 103p of the electricity meter. This protection circuit preferably uses an SMBJ12A TVS diode for overvoltage protection, which can withstand ±15kV electrostatic discharge impact and avoid damage to the downstream circuit by surge voltage.

[0059] After passing through the protection circuit, the signal enters the 485 signal interface module 103c. This module preferably uses the MAX485EESA+T transceiver, which supports a data transmission rate of 2.5Mbps and has a built-in fail-safe input circuit that automatically outputs a high level when the input is open to ensure communication reliability.

[0060] The output signal is isolated by a 6N137 optocoupler and then connected to the 485 communication interface of the compensation host computer 200. The optocoupler provides an isolation voltage of 2500Vac, effectively blocking ground loop interference.

[0061] The control module 103d preferably uses an STM32F103RCT6, which integrates a 32-bit ARM Cortex-M3 core with a working frequency of 50MHz and 51 general-purpose GPIO pins. Eight of these pins are used to output the channel selection signal of the analog switch 103b, and four pins control the switching circuit of the 485 signal interface module 103c, realizing time-sharing control logic that allows only a single energy meter to communicate with external devices at any given time.

[0062] The device is powered by a USB-to-serial chip 103m via a USB interface 103m. The preferred USB-to-serial chip 103m is CH340G, which supports full-speed USB 2.0 communication and has a built-in crystal oscillator, eliminating the need for an external clock circuit. The 5V input voltage is converted to 3.3V by an AMS1117-3.3 voltage regulator circuit, and then filtered by a 10μF electrolytic capacitor and a 0.1μF ceramic capacitor to provide a stable power supply with ripple of less than 50mV to the control module and peripherals, ensuring stable operation of the microcontroller in complex electromagnetic environments.

[0063] Furthermore, the task processing module 204 of the compensation host computer 200 is developed based on the QT framework, has a graphical interactive interface, and supports users to configure parameters and monitor tasks.

[0064] Furthermore, the meter position processing unit 204a automatically establishes a mapping relationship between the meter position address and the channel number of the analog switch 103b through the hardware channel of the scanning interface expansion device 100, and generates a meter position selection signal containing a channel selection instruction. This signal is transmitted to the USART interface of the control module 103d through a USB bus or an RS485 bus. The communication protocol adopts a custom Modbus-RTU format to ensure the accuracy and real-time performance of data transmission.

[0065] The parameter configuration unit 204b provides multi-dimensional setting options, including the acquisition cycle (adjustable from 1 min to 24 h), temperature compensation coefficient, error threshold, etc.

[0066] When the scheme execution unit 204c coordinates the interaction of various modules, it first drives the analog switch 103b to select the target energy meter channel through the GPIO pin of the control module 103d, and at the same time sends a synchronous acquisition command to the clock connection module 201.

[0067] The clock 102 preferably uses a SYN5104 time and frequency integrated tester, which has a built-in OCXO constant temperature crystal oscillator to provide a high-precision timing signal. The host computer calculates the daily timing error by comparing the time difference between the second pulse signal of the energy meter and the reference signal of the clock. If the error exceeds the preset threshold, the scheme execution unit 204c generates a calibration command according to the compensation strategy of the parameter configuration unit 204b, and writes it into the timing module of the energy meter 101 through the high-speed channel of the MAX485EESA+T transceiver, supporting dynamic adjustment of parameters such as crystal oscillator frequency and temperature compensation coefficient.

[0068] In this process, the digital tube 103f preferably uses a four-digit common cathode digital tube driven by a TM1637, which communicates with the control module 103d via an I2C interface to display the current table position number (01~16) in real time. The display brightness can be automatically adjusted according to the ambient light. The running light 103g uses a green LED, which flashes continuously when the device is in data acquisition or compensation mode; the pause light 103h uses a red LED, which lights up when a pause command is received from the host computer or a communication failure is detected. The status indication is achieved through a PNP transistor driving circuit, ensuring that on-site operators can monitor the device's working status in real time.

[0069] Example 2

[0070] Reference Figures 1-6 This is the second embodiment of the present invention. This embodiment differs from the first embodiment in that it provides a method for automatically collecting and compensating for daily timing errors in electricity meters, which includes the following steps:

[0071] S1: Establish a physical connection between the electricity meter 101 and the interface expansion device 100, establish a communication connection between the interface expansion device 100 and the compensation host computer 200 and the clock 102, and initialize the system.

[0072] S2: Select the target meter position and control the analog switch 103b to switch channels, connecting the second pulse signal and 485 signal path of the target energy meter 101.

[0073] S3: Collect daily timing error data of the target electricity meter 101, filter the data, compare the filtered data with the preset threshold, and if it exceeds the threshold, calculate the compensation value and write it into the electricity meter 101.

[0074] S4: After completing the above operations for all selected positions in sequence, generate and store a detailed report containing the measurement data and compensation results for each position.

[0075] Before selecting the target meter position and switching channels, the compensation host computer 200 reads the internal temperature sensor data of the electricity meter 101 through the electricity meter connection module 203 to confirm that the temperature remains within the target temperature range of ±2℃ for at least 15 minutes.

[0076] When switching channels, the control module 103d first disconnects all connected channels and then connects the channel of the target position.

[0077] When filtering the collected daily timing error data, a moving average algorithm is used to filter at least three consecutively collected data points.

[0078] The filtered error value is compared with the error threshold set by the parameter configuration unit 204b. If the three consecutive measurements are all within the threshold range, the calibration of the position is deemed qualified; otherwise, the compensation value is calculated based on the average error value.

[0079] The calculated compensation value is converted into an instruction conforming to the communication protocol format of the electricity meter 101 and written into the time register of the electricity meter 101 through the meter connection module 203.

[0080] If a certain table segment experiences three consecutive communication timeouts or verification errors during any operation step, the task processing module 204 automatically marks the table segment as abnormal and skips the table segment to continue executing the tasks of subsequent table segments.

[0081] After all tasks are completed, the generated detailed report distinguishes between normal and abnormal tabletops, and provides a fault code and possible cause analysis for each abnormal tabletop.

[0082] In summary, specifically, firstly, the 485 communication interface of the electricity meter 101 is connected to the 485 interface group of the interface expansion device 100 via a dedicated cable, and the second pulse signal interface is connected to the multi-function interface group of the electricity meter to ensure a stable physical connection.

[0083] During this process, the interface expansion device 100 establishes a communication link with the compensation host computer 200 via USB or RS485 bus, and at the same time completes the hardware connection of the reference signal channel with the clock 102 through the daytime clock interface.

[0084] The host computer initiates a self-test program, sequentially verifying the response of the analog switch 103b, the stability of the clock signal, and the communication protocol of the energy meter. After passing these checks, it initializes the communication parameters (such as a baud rate of 2400bps), clears the historical data cache, and completes system preparation.

[0085] Then, the host computer generates a table stop list based on the user input, and the table stop processing unit matches the corresponding hardware channel number.

[0086] Furthermore, before switching channels, the system reads the internal temperature sensor data of the electricity meter 101 through the electricity meter connection module 203 to confirm that the current temperature is within ±2℃ of the target test temperature and remains stable for at least 15 minutes, meeting the State Grid environmental testing specifications.

[0087] During this process, the control module 103d executes the "disconnect first, connect later" logic: first, it sends a full-channel disconnect command to the analog switch 103b, waits for the signal to stabilize for 50μs, and then connects the target meter position channel to ensure that only one energy meter signal path is activated at a time.

[0088] Then, the host computer synchronously acquires the reference second pulse signal of the clock and the real-time timing data of the energy meter, and continuously obtains at least 3 daily timing error values.

[0089] In this process, a moving average algorithm is used to filter the data three times, retaining the latest measurement value to calculate the mean. For example, the earliest data is removed and the average of the last three times is taken to reduce the impact of random noise.

[0090] Then, the filtered error value is compared with the error threshold set by the parameter configuration unit 204b, such as ±0.5s / 24h: if the three consecutive measurements are all within the threshold range, the calibration of the instrument position is deemed qualified; if at least one measurement exceeds the threshold, the compensation value is calculated based on the average error value using the temperature fitting or aging compensation strategy.

[0091] Furthermore, the calculated compensation value is converted into an instruction frame conforming to the communication protocol format of the electricity meter 101, and written into its time register through the electricity meter connection module 203 to complete the automatic calibration.

[0092] Finally, following a preset sequence, such as automatically switching table positions for channels 1 to 16, the channel switching, error acquisition, and compensation steps are repeated until all selected table positions have been processed.

[0093] During this process, if a certain table experiences three consecutive communication timeouts or verification errors, the task processing module 204 will automatically mark the table as abnormal, record the fault code (e.g., 01 indicates communication interruption, 02 indicates data verification failure), and skip the table to continue executing subsequent tasks.

[0094] The host computer generates detailed reports, distinguishing between normal and abnormal table positions. For each abnormal table position, it provides a fault code, possible causes, and troubleshooting suggestions. Possible causes include loose wiring or communication module failure. The reports also include basic test information, calibration data statistical analysis, and support PDF export and database storage for easy traceability and optimization.

[0095] The remaining structure is the same as that in Example 1.

[0096] Example 3

[0097] Reference Figures 1-6 This is the third embodiment of the present invention, which differs from the second embodiment in that: in order to eliminate the influence of temperature on the interface expansion device 100, the present invention conducts three tests respectively at ambient temperatures of -23°C, 25°C, and 55°C, following the test steps below:

[0098] 1. Place all meters into the high and low temperature test chamber, complete the connection with the interface expansion device 100, the clock 102, and the compensation host computer 200, and power on them.

[0099] 2. Import the table address into the table position selection module of the compensation host computer 200 in sequence, check the table position to be executed, configure the required task scheme, ensure normal communication, close the high and low temperature test chamber door, set the target temperature, and start executing the task.

[0100] 3. Continuously read the meter temperature. Once the meter temperature reaches the target temperature, maintain it at the target temperature for 15 minutes.

[0101] 4. Start reading the daily difference value of the current position continuously according to the reading frequency and number of times set in the task parameters. This step can filter out the unstable daily difference value error caused by the switching of the analog switch 103b channel.

[0102] 5. Start by determining whether the current daily error value meets the error allowable range set in the task parameters. If the requirement is met three times in a row, the remaining tasks of the current table position will no longer be executed, and the task of the next selected table position will be re-executed. If the error does not meet the requirement even once out of the three times, the next task of the current table position will be executed.

[0103] 6. Write the average of the three daily timing error values ​​from the previous task into the meter to calibrate the daily timing.

[0104] 7. Repeat steps 4-6.

[0105] 8. After all tasks in the current table have been completed, the tasks of the next table will begin to be executed.

[0106] In any task stage, if an unexpected error occurs in any task, such as communication failure, read failure, or write failure, the current table will be skipped and the next table task will be executed. After all selected table tasks have been completed, the task execution data of all tables can be exported with one click.

[0107] Specifically, in order to eliminate the influence of temperature on the interface expansion device 100, the present invention conducts three tests respectively under ambient temperatures of low temperature -23℃, normal temperature 25℃ and high temperature 55℃, following the test steps below.

[0108] Basic requirements: the daily difference should be within the range of -0.011232 to 0.0114912; meter model: DDZY43-M, where D is the electricity meter, D is single-phase, Z is smart, Y is prepaid, 43 is the identification code of the user company, and M is the meter submitted for inspection by the State Grid.

[0109] When the ambient temperature is 25℃, the meter temperature and daily variation are shown in Table 1 below:

[0110] Table 1

[0111]

[0112] When the ambient temperature is -23℃, the meter temperature and daily variation are shown in Table 2 below:

[0113] Table 2

[0114]

[0115] When the ambient temperature is +55℃, the meter temperature and daily variation are shown in Table 3 below:

[0116] Table 3

[0117]

[0118] Referring to Table 3, when the ambient temperature is +55℃, the corresponding command is executed according to the user-selected task and table position, specifically in the following steps:

[0119] 1. Turn on the 485 channel and second pulse channel of meter 1.

[0120] 2. Reading the meter address (645 protocol): The host computer sends a command to the meter to read the meter address. The meter replies with its meter address as 001314101203. The host computer fills the address in the table and displays it to the user.

[0121] 3. Continuously read daily deviation and temperature (645 protocol): Based on the user-configured cycle and frequency, first obtain the daily deviation value fed back by the daily deviation meter. The host computer fills the value in a table and displays it to the user (-0.3133278, indicating that the daily deviation of the meter is -0.3133278s / d at this time; 9999 is a custom error code. Since the channel has just been opened, the second pulse signal transmitted to the clock is unstable, resulting in an excessively large daily deviation value. When the host computer software reads this excessively large daily deviation value, it feeds back the error code). Then, send a command to read the temperature to the meter. The meter reports that the temperature is 56.8℃. The host computer software fills the temperature value in a table and displays it to the user.

[0122] 4. Continuously read daily difference and temperature (698 protocol): The user uses this task again (which is the same as the task corresponding to the 645 protocol, but different meters may only recognize the 698 protocol, or only the 645 protocol, or both protocols may be supported). This indicates that based on past experience, it is necessary to wait for a period of time until the daily difference stabilizes.

[0123] 5. Determine if the daily difference value meets the requirements: The host computer software determines whether the daily difference value of the electricity meter is within the allowable range based on the range of the daily difference value configured by the user. The determination is made three times. If all three determinations meet the requirements, it means that the daily difference value has met the requirements.

[0124] 6. Calibrate RTC (645 protocol): -0.320s / d is the average of the previous three daily difference values. The host computer sends this daily difference value to the meter. The meter itself calibrates the daily difference value at this temperature point based on the current temperature and the daily difference value provided by the host computer. If the meter is successfully calibrated, it sends a success signal to the host computer, which then displays the word "success" in a table for the user.

[0125] 7. Continuously read the daily difference value and temperature (645 protocol): After calibration in step 6, the user selects this task to view the daily difference value. -0.3133728, -0.1358208, +0.005184.... It can be clearly seen that after calibration, the daily difference value of the meter continues to decrease.

[0126] 8. Continuously read daily difference and temperature (698 protocol): When the user uses the task again, wait for the daily difference to stabilize.

[0127] 9. Determine if the daily deviation value meets the requirements: +0.0041472s / d, +0.0077760s / d, +0.0077760s / d. If all three values ​​meet the user-configured allowable range for daily deviation value, the RTC calibration will be completed, and the calibration of the next selected position can be performed.

[0128] Referring to Tables 1 to 3, it can be seen that the present invention, through the interface expansion device 100, can achieve precise control of the error of the real-time clock in the energy meter under various temperature environments, can monitor the temperature change of the real-time clock working environment in real time, and dynamically adjust the clock frequency compensation parameters according to the temperature-error correspondence.

[0129] Whether in a low-temperature environment of -23℃ or a high-temperature environment of 55℃, the device can quickly respond to temperature fluctuations and control the time error of the RTC within the preset range. It effectively solves the timing deviation problem caused by temperature drift of traditional real-time clocks and provides a stable and reliable clock guarantee for energy meters that require high-precision time reference.

[0130] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. An automatic acquisition and compensation device for daily timing error of an electricity meter, characterized in that: The utility model relates to an interface extension device (100) for connecting a plurality of electric energy meters (101) and a clock instrument (102), a compensation host computer (200) electrically connected with the interface extension device (100) for controlling the interface extension device (100) and realizing error collection and compensation, a communication connection between the interface extension device (100) and the compensation host computer (200) for transmitting control signals and data, a mainboard (103) further provided in the interface extension device (100), a second pulse signal interface module (103a), an analog switch (103b), a 485 signal interface module (103c) and a control module (103d) provided on the mainboard (103), the second pulse signal interface module (103a) accesses the second pulse signal of the electric energy meter (101) through a pin and female seat structure, all negative terminals of the second pulse signal interface module (103a) are connected to a common ground terminal after being short-circuited, and the positive terminal is electrically connected with the second pulse input terminal of the clock instrument (102) through the analog switch (103b), the 485 signal interface module (103c) accesses the 485 signal of the electric energy meter (101) through a pin and female seat structure, the 485A terminal and the 485B terminal of the 485 signal interface module (103c) are respectively electrically connected with the 485 communication interface of the compensation host computer (200) through a signal switching circuit, the control module (103d) is electrically connected with the signal switching circuit of the 485 signal interface module (103c) and the analog switch (103b) respectively, a CPU simulation / programming download interface (103e) is further provided on the mainboard (103), the CPU simulation / programming download interface (103e) is electrically connected with the debugging interface of the control module (103d), and is used for program burning and debugging, a number tube (103f) is electrically connected with the control module (103d) through an I / O interface and is configured to display the currently selected electric energy meter position number, a running lamp (103g) and a pause lamp (103h) are respectively electrically connected with the state indication output terminal of the control module (103d) through a driving circuit and are configured to indicate the working state of the device, a reserved I / O interface (103k) is electrically connected with the general I / O port of the control module (103d) and is used for expanding external function modules, a USB interface (103m) is electrically connected with the communication port of the control module (103d) through a USB-to-serial chip and is configured to realize data communication with the compensation host computer (200) and device power supply, a reset button (103n) is electrically connected with the reset pin of the control module (103d) and is configured to trigger device reset, an electric energy meter 485 interface group (103p) is further provided on the mainboard (103) and includes a plurality of first 485A contacts (103p-1) and first 485B contacts (103p-2), and each contact is electrically connected with the corresponding channel of the 485 signal interface module (103c) through a protection circuit. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The meter multifunctional interface group (103q) includes RTC+ contact groups (103q-1) and RTC- contact groups (103q-2), each of which is electrically connected to a corresponding channel of the second pulse signal interface module (103a) through a signal conditioning circuit; The day chronograph interface (103r) includes positive contact (103r-1) and negative contact (103r-2), which are electrically connected to the corresponding input terminals of the clock instrument (102) through an isolation circuit; The PC RS485 interface (103s) includes third 485A contact (103s-1) and fourth 485B contact (103s-2), which are electrically connected to the 485 communication interface of the compensation host computer (200) through the RS485 transceiver; The compensation host computer (200) includes a clock instrument connection module (201), an expansion device connection module (202), and a meter connection module (203); The clock instrument connection module (201) is electrically connected to the communication interface of the clock instrument (102) through a communication bus; The expansion device connection module (202) is electrically connected to the USB interface (103m) of the interface expansion device (100) or the PC RS485 interface (103s) through a USB bus or an RS485 bus; The meter connection module (203) is electrically connected to the 485 communication interface of the electric energy meter (101) through the 485 signal interface module (103c) of the interface expansion device (100) and is configured to send read-write commands and receive electric energy meter data; The compensation host computer (200) further includes a task processing module (204), which is in communication connection with the clock instrument connection module (201), the expansion device connection module (202), and the meter connection module (203); The task processing module (204) manages the register address mapping relationship through a register processing unit (204a) and generates a register selection instruction; The task processing module (204) sets task execution parameters and error compensation strategies through a parameter configuration unit (204b); The task processing module (204) coordinates the execution of task processes by each module through a scheme execution unit (204c) and stores the execution results.

2. An automatic acquisition and compensation method for daily timing errors of an electric energy meter, characterized in that: The electric energy meter daily timing error automatic acquisition and compensation device based on claim 1 further includes, S1: Establishing physical connection between the electric energy meter (101) and the interface expansion device (100), establishing communication connection between the interface expansion device (100) and the compensation host computer (200) and the clock instrument (102), and initializing the system; S2: Selecting a target register and controlling the analog switch (103b) to switch channels to connect the second pulse signal and the 485 signal path of the target electric energy meter (101); S3: Collecting the daily timing error data of the target electric energy meter (101), filtering the data, comparing the filtered data with a preset threshold, and if the threshold is exceeded, calculating the compensation value and writing it into the electric energy meter (101); S4: After sequentially completing the above operations for all selected registers, generating and storing a detailed report containing the measurement data and compensation results of each register.

3. The method for automatic acquisition and compensation of daily timing error of electric energy meter according to claim 2, characterized in that: Before selecting target meter and switching channel, the host computer (200) reads the internal temperature sensor data of the electric energy meter (101) through the electric meter connection module (203) to confirm that the temperature is within the target temperature ± 2℃ range for at least 15 minutes; When switching the channel, the control module (103d) first disconnects all the channels that have been connected, and then connects the channel of the target meter.

4. The method for automatic acquisition and compensation of daily timing error of electric energy meter according to claim 3, characterized in that: When filtering the collected daily time error data, a sliding average algorithm is used to filter at least three consecutive data; The filtered error value is compared with the error threshold set by the parameter configuration unit (204b). If the three consecutive measurement values are within the threshold range, the meter is determined to be calibrated, otherwise the compensation value is calculated according to the average error value; The calculated compensation value is converted into an instruction in the format of the electric energy meter (101) communication protocol and written into the time register of the electric energy meter (101) through the electric meter connection module (203).

5. The method for automatic acquisition and compensation of daily timing error of electric energy meter according to claim 4, characterized in that: In any operation step, if a meter has three consecutive communication timeouts or verification errors, the task processing module (204) automatically marks the meter as abnormal and skips the meter to continue executing the tasks of the subsequent meters; After completing all tasks, the generated detailed report distinguishes between normal meters and abnormal meters, and provides fault codes and possible cause analysis for each abnormal meter.

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