Intelligent electric meter clock punctuality precision test system and method

Abstract

The invention discloses an intelligent electric meter clock punctuality precision test system and method.The system comprises an upper computer and a test terminal, and the upper computer is used for sending an initial test instruction and a final test instruction to the test terminal; the test terminal is used for detecting a clock pulse signal of a to-be-tested intelligent electric meter and a standard second pulse signal of a standard clock source according to the initial test instruction and the final test instruction so as to read an electric meter communication time code of an internal clock of the intelligent electric meter and a standard communication time code of the standard clock source, and synchronously controlling a millisecond timer to start and stop to realize accurate timing; and the upper computer carries out calculation according to the time difference between the electricity meter communication time code and the standard clock source communication time code and the timing value of the millisecond timer so as to obtain an accurate final clock skew result. Compared with the prior art that the second-level resolution of the time of the electric energy meter is read only through communication, the system and the method have the advantages that the resolution can be improved to the millisecond level, and the accuracy and the effectiveness of a test result are greatly guaranteed.

Description

A smart meter clock timekeeping accuracy testing system and method Technical Field

[0001] This invention relates to the field of clock accuracy testing technology, and more specifically, to a system and method for testing the clock timekeeping accuracy of a smart meter. Background Technology

[0002] Smart meters are widely used active energy metering devices. Besides basic energy metering functions, smart meters also have time-of-use (TOU) metering capabilities, meaning they measure electricity separately according to different time periods and rates. TOU metering relies on a real-time clock inside the smart meter as the time reference; therefore, the accuracy of the smart meter's internal clock is clearly specified in relevant energy meter technical standards. For example, the Chinese national standard for energy meters explicitly stipulates that the timekeeping accuracy requirement for smart meters is... 1.5s / 72h (GB / T17215.211-2021 "Electrical Measuring Equipment (AC) - General Requirements, Test Methods and Test Conditions - Part 11: Measuring Equipment" 7.13.2.2 Clock Test Using Backup Power). According to the test method in the standard, the clock of the energy meter is synchronized during the first test, setting the meter time to match the standard clock source. After a 72-hour power outage, the meter is powered on again to retest the clock accuracy. The meter time is read, and the deviation between the meter time and the standard clock source time is determined to meet the requirement of an absolute value less than 1.5s / 72h. However, the above method has the following problems: when synchronizing the energy meter clock through the communication interface, synchronization can only be achieved to the second. During the retest, only the meter time accurate to the second (year, month, day, hour, minute, second) can be obtained. Therefore, the resolution of the test results is only accurate to the second, resulting in a significant deviation from the actual results. Summary of the Invention

[0003] To address the problem that existing technologies for synchronizing smart meter clocks via communication interfaces can only achieve second-level accuracy, resulting in significant discrepancies between actual and test clock accuracy results, this invention proposes a smart meter clock timing accuracy testing system and method. By using the change between the initial and final measured clock deviations, the clock synchronization error of the smart meter under test is eliminated, thereby improving the accuracy of the clock deviation test results.

[0004] According to one aspect of the present invention, a smart meter clock timekeeping accuracy testing system is provided. The system includes a host computer and a test terminal. The test terminal integrates a microprocessor (MCU). The host computer is used to send an initial test command to the test terminal, calculate the initial test clock deviation based on the first meter time, the first standard time, and the first timer time transmitted by the test terminal during the initial test, and record the initial test time. When the power-off waiting time of the smart meter to be tested after the initial test is not less than a preset first time interval, the host computer sends a final test command to the test terminal, calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer time transmitted by the test terminal during the final test, and records the final test time. The system calculates the clock accuracy of the smart meter to be tested based on the initial test time, the final test time, the first time interval, the initial test clock deviation, and the final test clock deviation. The test terminal is used to test the final clock deviation of the smart meter. After the MCU receives the initial test command, it starts a millisecond timer at the first moment when the falling edge of the second pulse of the smart meter to be tested is detected, and at the second moment after a preset second time interval, it acquires the first meter time corresponding to the second moment. At the third moment after the first moment, when the falling edge of the second pulse of the standard clock source is detected, it stops the millisecond timer to acquire the first timer time, and at the fourth moment after a preset third time interval, it acquires the first standard time of the standard clock source corresponding to the fourth moment. After receiving the final test command, the MCU sequentially acquires the second meter time corresponding to the second moment, the second timer time corresponding to the third moment, and the second standard time corresponding to the fourth moment, following the steps of the initial test.

[0005] According to another aspect of the present invention, a method for testing the clock accuracy of a smart meter is provided. The method includes: a host computer sending an initial test command to a test terminal; after receiving the initial test command, the test terminal starts an MCU millisecond timer at a first moment when a falling edge of the second pulse of the smart meter to be tested is detected, and at a second moment after a preset second time interval, acquires the first meter time corresponding to the second moment; at a third moment after the first moment when a falling edge of the second pulse of a standard clock source is detected, the millisecond timer stops to acquire the first timer time, and at a fourth moment after a preset third time interval, acquires the first standard time of the standard clock source corresponding to the fourth moment; and transmits the first meter time, the first standard time, and the first timer time to the host computer; the host computer, based on the first meter time, then... The system calculates the initial test clock deviation using a standard time and a first timer, and records the initial test time. When the power-off waiting time of the smart meter to be tested after the initial test is not less than a preset first time interval, the host computer sends a final test command to the test terminal. After the MCU receives the final test command, the test terminal sequentially obtains the second meter time corresponding to the second moment, the second timer time corresponding to the third moment, and the second standard time corresponding to the fourth moment, following the steps of executing the initial test. It also transmits the second meter time, the second standard time, and the second timer time to the host computer. The host computer calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer time, and records the final test time. It also calculates the final clock deviation of the smart meter to be tested based on the initial test time, the final test time, the first time interval, the initial test clock deviation, and the final test clock deviation.

[0006] The present invention provides a smart meter clock timing accuracy testing system and method, wherein the system includes a host computer and a test terminal. The host computer is used to send an initial test command to the test terminal, calculate the initial test clock deviation based on the first meter time, the first standard time, and the first timer time transmitted by the test terminal during the initial test, and record the initial test time. When the power-off waiting time of the smart meter to be tested after the initial test is not less than a preset first time interval, the host computer sends a final test command to the test terminal, calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer time transmitted by the test terminal during the final test, and records the final test time. The final clock deviation of the smart meter to be tested is calculated based on the initial test time, the final test time, the first time interval, the initial test clock deviation, and the final test clock deviation. The terminal is configured to, after the microprocessor (MCU) receives the initial test instruction, start the MCU millisecond timer at the first moment when the falling edge of the second pulse of the smart meter to be tested is detected, and at the second moment after a preset second time interval, obtain the first meter time of the smart meter to be tested corresponding to the second moment; at the third moment after the first moment when the falling edge of the second pulse of the standard clock source is detected, stop the millisecond timer to obtain the first timer time, and at the fourth moment after a preset third time interval, obtain the first standard time of the standard clock source corresponding to the fourth moment; and after the MCU receives the final test instruction, sequentially obtain the second meter time corresponding to the second moment, the second timer time corresponding to the third moment, and the second standard time corresponding to the fourth moment according to the steps of executing the initial test. The system and method detect the clock pulse signal of the smart meter under test and the standard second pulse signal of a standard clock source to read the meter communication time code (referring to the time of the first and second meters) of the smart meter's internal clock and the standard communication time code (referring to the first and second standard times) of the standard clock source. Simultaneously, they control the start and stop of a millisecond timer to achieve precise timing (referring to the timing of the first and second timers). Then, the time difference between the meter communication time code and the standard clock source communication time code is used together with the millisecond timer value to calculate the accurate final clock deviation result. Compared to relying solely on communication to read the meter time with second-level resolution, this invention improves the resolution to the millisecond level, ensuring the accuracy and validity of the test results. Attached Figure Description

[0007] The exemplary embodiments of the present invention can be more fully understood by referring to the following figures: Figure 1 is a structural schematic diagram of a smart meter clock timekeeping accuracy testing system according to an embodiment of the present invention; Figure 2 is a flowchart of a host computer test according to an embodiment of the present invention; Figure 3 is a flowchart of a test terminal microprocessor test according to an embodiment of the present invention; Figure 4 is a timing diagram of the initial test / final test according to an embodiment of the present invention; Figure 5 is a diagram of a host computer test interface according to an embodiment of the present invention; and Figure 6 is a flowchart of a smart meter clock timekeeping accuracy testing method according to an embodiment of the present invention. Detailed Implementation

[0008] Exemplary embodiments of the invention will now be described with reference to the accompanying drawings. However, the invention may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided to fully and completely disclose the invention and to fully convey its scope to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the drawings is not intended to limit the invention. In the drawings, the same units / elements are referred to by the same reference numerals.

[0009] Unless otherwise stated, the terms used herein (including technical terms) have their common meaning as understood by one of ordinary skill in the art. Furthermore, it is understood that terms defined in commonly used dictionaries should be understood to have a meaning consistent with the context of their relevant field, and not to be interpreted as having an idealized or overly formal meaning.

[0010] Figure 1 is a schematic diagram of a smart meter clock timekeeping accuracy testing system according to an embodiment of the present invention. As shown in Figure 1, the system includes a host computer 101 and a test terminal 102. The test terminal 102 integrates an MCU. The host computer 101 sends an initial test command to the test terminal 102, calculates the initial test clock deviation based on the first meter time, the first standard time, and the first timer time transmitted by the test terminal 102 during the initial test, and records the initial test time. When the power-off waiting time of the smart meter to be tested after the initial test is not less than a preset first time interval, the host computer sends a final test command to the test terminal 102, calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer time transmitted by the test terminal during the final test, and records the final test time. The system calculates the clock accuracy of the smart meter to be tested based on the initial test time, the final test time, the first time interval, the initial test clock deviation, and the final test clock deviation. Final clock deviation; Test terminal 102, after the MCU receives the initial test command, at the first moment when the falling edge of the second pulse of the smart meter to be tested is detected, starts the MCU millisecond timer, and at the second moment after a preset second time interval, obtains the first meter time of the smart meter to be tested corresponding to the second moment; at the third moment after the first moment when the falling edge of the second pulse of the standard clock source is detected, stops the millisecond timer to obtain the first timer time, and at the fourth moment after a preset third time interval, obtains the first standard time of the standard clock source corresponding to the fourth moment; and after the MCU receives the final test command, it sequentially obtains the second meter time corresponding to the second moment, the second timer time corresponding to the third moment, and the second standard time corresponding to the fourth moment according to the steps of executing the initial test.

[0011] Preferably, the test terminal 102 further includes a peripheral interface circuit, through which the MCU realizes communication and signal acquisition with the standard clock source, the smart meter to be tested, and the host computer.

[0012] Preferably, the standard clock source is the BeiDou module integrated inside the test terminal, or an external time and frequency terminal connected to the test terminal through an external interface circuit.

[0013] Furthermore, the power supply for the test terminal can be an internal power supply and / or an external power supply.

[0014] Preferably, the host computer 101 calculates the initial test clock deviation based on the first meter time, the first standard time, and the first timer time of the initial test transmission performed by the test terminal 102, and calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer time of the final test transmission performed by the test terminal. The calculation formulas are as follows: ΔT0 = T1 - T0 + TM0 ΔT1 = T3 - T2 + TM1 Wherein, ΔT0 and ΔT1 are the initial test clock deviation and the final test clock deviation, respectively; T0, T1, and TM0 are the first meter time, the first standard time, and the first timer time, respectively; and T2, T3, and TM1 are the second meter time, the second standard time, and the second timer time, respectively.

[0015] Preferably, the host computer 101 calculates the final clock deviation of the smart meter to be tested based on the initial test time, final test time, first time interval, initial test clock deviation, and final test clock deviation. The calculation formula is: ΔT = (ΔT1 - ΔT0) * Δt0 / TSTS = T L –T F In the formula, Δt0, ΔT0, ΔT1, and ΔT represent the first time interval, the initial clock deviation, the final clock deviation, and the final clock deviation, respectively, and T represents the final time interval. F and T L These represent the initial test time and the final test time, respectively, with TS being the actual time interval between the initial test and the final test.

[0016] As can be seen from the formula for calculating the final clock deviation described above, the ΔT1-ΔT0 used in the smart meter clock timekeeping accuracy test system of the present invention is the change value between the initial clock deviation and the final clock deviation, which can eliminate the clock synchronization error of the energy meter.

[0017] Preferably, when there are multiple smart meters to be tested, the host computer 101 is further configured to obtain and store the information tags of the smart meters to be tested during the initial test before sending the initial test command to the test terminal, and after obtaining the information tags of the smart meters to be tested during the final test before sending the final test command to the test terminal, query and display the initial test time and initial test clock deviation corresponding to the information tags.

[0018] Preferably, the host computer 101 is further configured to determine the accuracy judgment result of the smart meter to be tested according to the set timekeeping accuracy judgment rule, wherein the expression of the timekeeping accuracy judgment rule is: In the formula, ΔT is the final clock offset. max The set clock deviation threshold is used; when the final clock deviation meets the timekeeping accuracy judgment rule, the timekeeping accuracy of the smart meter to be tested is determined to meet the requirements and the product is qualified; otherwise, the timekeeping accuracy does not meet the requirements and the product is unqualified.

[0019] In this embodiment, the test terminal 102 uses an internally integrated Beidou module as the standard clock source. The first time interval is set to 72 hours in accordance with the requirements of GB / T17215.211-2021 "Electrical measuring equipment (AC) - General requirements, test methods and test conditions - Part 11: Measuring equipment" 7.13.2.2, and the clock deviation threshold is set to 1.5s / 72h.

[0020] Figure 2 is a flowchart of the host computer test according to an embodiment of the present invention. When the standard clock source is the Beidou module integrated inside the test terminal 102, the process of the host computer 101 performing preliminary / final tests on the smart meter to be tested to determine the final clock error of the smart meter clock is shown in Figure 2. In Figure 2, the information label of the smart meter to be tested is a barcode number, which can be obtained by scanning with a barcode scanner. Figure 5 is a diagram of the host computer test interface, which shows buttons for the first test and the last test. By clicking the button, the host computer can trigger the MCU of the test terminal to send preliminary / final test commands. When the command sent is a preliminary test command, the preliminary test data uploaded by the MCU is the first meter time, the first standard time, and the first timer time. Similarly, when the command sent is a final test command, the final test data uploaded by the MCU is the second meter time, the second standard time, and the second timer time. When the initial and final test clock deviations are calculated based on the initial and final test data, and the time interval TS is determined according to the initial and final test times, with the first time interval being 72 hours, the final clock deviation can be calculated, and an accuracy judgment result can be generated according to the timekeeping accuracy judgment rules. In Figure 2, the operation of calculating the change value "*72 / TS" when calculating the final clock deviation calculates the corresponding result of the clock deviation change value over 72 hours based on the actual test interval TS, ensuring the rigor of the test data. Even if the operator performs the final test at a time greater than 72 hours (e.g., 75 hours), the judgment is still based on the result corresponding to 72 hours, avoiding the situation where critical data is judged as unqualified due to human factors. In other words, when a standard-specified first time interval exists, the final clock deviation formula of this invention avoids the situation where critical data is judged as unqualified due to human factors, improving the accuracy of smart meter clock timekeeping accuracy testing.

[0021] Figure 3 is a flowchart of the test terminal microprocessor test according to an embodiment of the present invention. As shown in Figure 3, when the standard clock source is the Beidou module, after the test system is powered on, the test terminal MCU first initializes the Beidou module, including configuring the module baud rate, configuring the module output information, selecting the galaxy (Beidou / GPS), etc. After the Beidou module is normally connected, it waits for the clock pulse signal of the smart meter. After receiving the clock pulse signal at time t0, it starts the precision millisecond timer TM; then at time t1, it reads the meter communication time code of the internal clock of the smart meter, that is, the first meter time T0 (year, month, day, hour, minute, second, communication protocol can be selected DL / T645 or DL / T698). The second time interval Δt1 is preset between t0 and t1. The second time interval Δt1 is set according to ensuring that the value in the register when reading the smart meter time has been updated to the standard. In this preferred embodiment, it is set to 200ms, while waiting for the standard pulse (second pulse) of the Beidou module. When the BeiDou module receives a standard pulse at time t2, the TM timer stops, and the first timer TM0 is acquired (theoretically, the value of TM0 is less than or equal to 1000ms; in testing, the threshold is appropriately relaxed, and an error is reported when the value of TM0 is greater than 1010; the same applies to the TM1 value in the final test). Then, at time t3, after a preset third time interval Δt2 (the principle of setting the third time interval can be referred to the second time interval), the standard communication time code of the BeiDou module is read, which is the first standard time T1 (year, month, day, hour, minute, second). The MCU transmits the initial test data T0, T1, and TM0 to the host computer through the communication interface. The host computer calculates the initial test clock deviation ΔT0 based on this and records the Beijing time at the time of the initial test as the initial test time (accurate to the second), where ΔT0 = T1 - T0 + TM0. Subsequently, the host computer displays and stores the data and waits for the final test 72 hours later. The terminal steps are the same as the initial test steps and will not be repeated here.

[0022] In this preferred embodiment, the theoretical upper limit for TM0 and TM1 should be 1000ms. However, considering the possible differences in the edge width of the second pulse from different manufacturers, which may cause errors in the pulse edge (these errors should be within the microsecond range) and counter errors (the counter updates every millisecond), a custom value of 10ms is added. This custom value can be modified according to the actual situation on site.

[0023] Figure 4 is a timing diagram of the initial / final test according to an embodiment of the present invention. As shown in Figure 4, regardless of whether the test terminal performs the initial or final test, the timing sequence for acquiring the smart meter time, the BeiDou module standard time, and the timer timing is the same. After the MCU receives the initial / final test command, the time at which the falling edge of the smart meter's second pulse is detected is recorded as t0, and the MCU millisecond timer is started at t0. At t1, after the second time interval Δt1, the smart meter time is read, the time at which the falling edge of the BeiDou module's second pulse is detected is recorded as t2, and the MCU millisecond timer is stopped at t2. The first / second timer timing TM0 / TM1 is then acquired, and the BeiDou module standard time is read at t3, after the third time interval Δt2. It should be noted that determining the meter time and standard time by sequentially detecting the rising edges of the second pulses of the smart meter and the standard clock source is also feasible. The use of the falling edge of the second pulse in this embodiment does not constitute a limitation on determining the meter time and standard time by detecting the rising edge of the second pulse.

[0024] Figure 5 shows the host computer test interface according to an embodiment of the present invention. As shown in Figure 5, when there are multiple smart meters to be tested, based on the list of meters to be tested on the right, they are tested sequentially in batches and by rack, first by initial test, and then by final test. The real-time data on the left displays the meter time and standard time during the test. The clock switch position is used to select the type of standard clock source. The test detection column displays relevant information about the smart meters currently being tested, where the first test and the last test correspond to the initial test and the final test, respectively. The test start time and test end time correspond to the initial test time and the final test time, the start test time difference and the end test time difference correspond to the initial test clock deviation and the final test clock deviation, the test interval corresponds to the actual time interval between the initial test and the final test, and the error result corresponds to the final clock error. The data query column is used to query the timekeeping accuracy test results of the smart meters in the list of meters to be tested on the right, based on the meter number.

[0025] Figure 6 is a flowchart of a smart meter clock timekeeping accuracy testing method according to an embodiment of the present invention. As shown in Figure 6, the smart meter clock timekeeping accuracy testing method of this embodiment begins with step 601.

[0026] In step 601, the host computer sends an initial test command to the test terminal; in step 602, after receiving the initial test command, the test terminal starts the MCU millisecond timer at the first moment when it detects the falling edge of the second pulse of the smart meter to be tested, and at the second moment after a preset second time interval, it obtains the first meter time of the smart meter to be tested corresponding to the second moment; at the third moment after the first moment when it detects the falling edge of the second pulse of the standard clock source, it stops the millisecond timer to obtain the first timer time, and at the fourth moment after a preset third time interval, it obtains the first standard time of the standard clock source corresponding to the fourth moment; and transmits the first meter time, the first standard time, and the first timer time to the host computer; in step 603, the host computer calculates the initial test clock offset based on the first meter time, the first standard time, and the first timer time. The system calculates and records the initial test time. In step 604, when the power-off waiting time of the smart meter to be tested after the initial test is not less than a preset first time interval, the host computer sends a final test command to the test terminal. In step 605, after the MCU receives the final test command, the test terminal sequentially obtains the second meter time corresponding to the second time, the second timer time corresponding to the third time, and the second standard time corresponding to the fourth time according to the steps of executing the initial test. The system also transmits the second meter time, the second standard time, and the second timer time to the host computer. In step 606, the host computer calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer time and records the final test time. The system also calculates the final clock deviation of the smart meter to be tested based on the initial test time, the final test time, the first time interval, the initial test clock deviation, and the final test clock deviation.

[0027] Preferably, the host computer calculates the initial clock deviation based on the time of the first meter, the first standard time, and the first timer, and calculates the final clock deviation based on the time of the second meter, the second standard time, and the second timer, respectively. The calculation formulas are as follows: ΔT0 = T1 - T0 + TM0 ΔT1 = T3 - T2 + TM1 Wherein, ΔT0 and ΔT1 are the initial clock deviation and the final clock deviation, respectively; T0, T1, and TM0 are the time of the first meter, the first standard time, and the first timer, respectively; and T2, T3, and TM1 are the time of the second meter, the second standard time, and the second timer, respectively.

[0028] Preferably, the host computer calculates the final clock deviation of the smart meter to be tested based on the initial test time, final test time, first time interval, initial test clock deviation, and final test clock deviation. The calculation formula is: ΔT = (ΔT1 - ΔT0) * Δt0 / TSTS = T L –T FIn the formula, Δt0, ΔT0, ΔT1, and ΔT represent the first time interval, the initial clock deviation, the final clock deviation, and the final clock deviation, respectively, and T represents the final time interval. F and T L These represent the initial test time and the final test time, respectively, with TS being the actual time interval between the initial test and the final test.

[0029] The present invention has been described with reference to a few embodiments. However, it will be apparent to those skilled in the art that other embodiments besides those disclosed above fall equivalently within the scope of the present invention.

[0030] Generally, all terms used in this invention are interpreted according to their ordinary meaning in the art, unless otherwise expressly defined herein. All references to “a / the / the [device, component, etc.]” ​​are openly interpreted as at least one instance of said device, component, etc., unless otherwise expressly stated. The steps of any method disclosed herein need not be performed in the exact order disclosed, unless explicitly stated otherwise.

[0031] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0032] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in one or more blocks of the flowchart illustrations and / or one or more blocks of the block diagrams.

[0033] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that implement the functions specified in one or more flowcharts and / or one or more block diagrams.

[0034] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions specified in one or more flowcharts and / or one or more block diagrams.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the present invention.

Claims

1. A smart meter clock timekeeping accuracy testing system, characterized in that, The system includes a host computer and a test terminal. The test terminal integrates a microprocessor (MCU). The host computer sends an initial test command to the test terminal, calculates the initial test clock deviation based on the first meter time, the first standard time, and the first timer used by the test terminal for initial test transmission, and records the initial test time. When the power-off waiting time of the smart meter to be tested after the initial test is not less than a preset first time interval, the host computer sends a final test command to the test terminal, calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer used by the test terminal for final test transmission, and records the final test time. The final clock deviation of the smart meter to be tested is calculated based on the initial test time, the final test time, the first time interval, the initial test clock deviation, and the final test clock deviation. The microprocessor (MCU) receives the initial test instruction and, at the first moment when it detects the falling edge of the second pulse of the smart meter to be tested, starts the MCU millisecond timer; at the second moment after a preset second time interval, it acquires the first meter time corresponding to the second moment; at the third moment after the first moment when it detects the falling edge of the second pulse of the standard clock source, it stops the millisecond timer to acquire the first timer time; at the fourth moment after a preset third time interval, it acquires the first standard time of the standard clock source corresponding to the fourth moment; and after the MCU receives the final test instruction, it sequentially acquires the second meter time corresponding to the second moment, the second timer time corresponding to the third moment, and the second standard time corresponding to the fourth moment, following the steps of executing the initial test.

2. The system according to claim 1, characterized in that, The test terminal also includes a peripheral interface circuit, through which the MCU communicates with the standard clock source, the smart meter to be tested, and the host computer and acquires signals.

3. The system according to claim 2, characterized in that, The standard clock source is either the BeiDou module integrated inside the test terminal or an external time and frequency terminal connected to the test terminal via an external interface circuit.

4. The system according to claim 1, characterized in that, The host computer calculates the initial test clock deviation based on the first meter time, the first standard time, and the first timer time of the initial test transmission performed by the test terminal, and calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer time of the final test transmission performed by the test terminal. The calculation formulas are as follows: ΔT0 = T1 - T0 + TM0 ΔT1 = T3 - T2 + TM1 Wherein, ΔT0 and ΔT1 are the initial test clock deviation and the final test clock deviation, respectively; T0, T1, and TM0 are the first meter time, the first standard time, and the first timer time, respectively; and T2, T3, and TM1 are the second meter time, the second standard time, and the second timer time, respectively.

5. The system according to claim 1, characterized in that, The host computer calculates the final clock deviation of the smart meter to be tested based on the initial test time, final test time, first time interval, initial test clock deviation, and final test clock deviation. The calculation formula is: ΔT = (ΔT1 - ΔT0) * Δt0 / TSTS = T L –T F In the formula, Δt0, ΔT0, ΔT1, and ΔT represent the first time interval, the initial clock deviation, the final clock deviation, and the final clock deviation, respectively, and T represents the final time interval. F and T L These represent the initial test time and the final test time, respectively, with TS being the actual time interval between the initial test and the final test.

6. The system according to claim 1, characterized in that, When there are multiple smart meters to be tested, the host computer is also used to obtain and store the information tags of the smart meters to be tested during the initial test before sending the initial test command to the test terminal, and after obtaining the information tags of the smart meters to be tested during the final test before sending the final test command to the test terminal, query and display the initial test time and initial test clock deviation corresponding to the information tags.

7. The system according to claim 1, characterized in that, The host computer is also used to determine the accuracy judgment result of the smart meter to be tested according to the set timekeeping accuracy judgment rule, wherein the expression of the timekeeping accuracy judgment rule is: In the formula, ΔT is the final clock offset. max The set clock deviation threshold is used; when the final clock deviation meets the timekeeping accuracy judgment rule, the timekeeping accuracy of the smart meter to be tested is determined to meet the requirements and the product is qualified; otherwise, the timekeeping accuracy does not meet the requirements and the product is unqualified.

8. A method for testing the clockkeeping accuracy of a smart meter using any one of the systems described in claims 1 to 7, characterized in that, The method includes: a host computer sending an initial test command to a test terminal; after receiving the initial test command, the test terminal starts an MCU millisecond timer at a first moment when it detects the falling edge of the second pulse of the smart meter to be tested, and at a second moment after a preset second time interval, obtains the first meter time of the smart meter to be tested corresponding to the second moment; at a third moment after the first moment when it detects the falling edge of the second pulse of the standard clock source, it stops the millisecond timer to obtain the first timer time, and at a fourth moment after a preset third time interval, obtains the first standard time of the standard clock source corresponding to the fourth moment; and transmits the first meter time, the first standard time, and the first timer time to the host computer; the host computer calculates an initial test time based on the first meter time, the first standard time, and the first timer time. The system measures the clock deviation and records the initial test time. When the power-off waiting time of the smart meter to be tested after the initial test is not less than a preset first time interval, the host computer sends a final test command to the test terminal. After the MCU receives the final test command, the test terminal sequentially obtains the second meter time corresponding to the second time, the second timer time corresponding to the third time, and the second standard time corresponding to the fourth time, following the steps of executing the initial test. It also transmits the second meter time, the second standard time, and the second timer time to the host computer. The host computer calculates the final test clock deviation based on the second meter time, the second standard time, and the second timer time and records the final test time. It also calculates the final clock deviation of the smart meter to be tested based on the initial test time, the final test time, the first time interval, the initial test clock deviation, and the final test clock deviation.

9. The method according to claim 8, characterized in that, The host computer calculates the initial clock deviation based on the time of the first meter, the first standard time, and the first timer, and calculates the final clock deviation based on the time of the second meter, the second standard time, and the second timer. The calculation formulas are as follows: ΔT0 = T1 - T0 + TM0 ΔT1 = T3 - T2 + TM1 Wherein, ΔT0 and ΔT1 are the initial clock deviation and the final clock deviation, respectively; T0, T1, and TM0 are the time of the first meter, the first standard time, and the first timer, respectively; and T2, T3, and TM1 are the time of the second meter, the second standard time, and the second timer, respectively.

10. The method according to claim 8, characterized in that, The host computer calculates the final clock deviation of the smart meter to be tested based on the initial test time, final test time, first time interval, initial test clock deviation, and final test clock deviation. The calculation formula is: ΔT = (ΔT1 - ΔT0) * Δt0 / TSTS = T L –T F In the formula, Δt0, ΔT0, ΔT1, and ΔT represent the first time interval, the initial clock deviation, the final clock deviation, and the final clock deviation, respectively, and T represents the final time interval. F and T L These represent the initial test time and the final test time, respectively, with TS being the actual time interval between the initial test and the final test.

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