A self-test feedback method for three-phase electric meter

Abstract

The present invention discloses a self-test feedback method for a three-phase electricity meter, which is used for the three-phase electricity meter to perform self-test feedback on its own sampling accuracy, including step S1: after a current switching switch located at a current end receives a current self-test instruction transmitted by a processor of the three-phase electricity meter according to a preset period, it switches the normal current sampling circuit to the current self-test circuit, thereby allowing the current self-test circuit to detect the current currently input to the current end. The self-test feedback method for a three-phase electricity meter disclosed by the present invention can notify the customer through communication, an alarm light, or a buzzer when the accuracy of the three-phase electricity meter is abnormal. The customer can replace the electricity meter according to the alarm prompt, and will not continue to use the electricity meter when the accuracy of the electricity meter is out of tolerance.

Description

Technical Field

[0001] The invention belongs to the technical field of self-testing and feedback of three-phase electric meters, and in particular relates to a self-testing and feedback method of a three-phase electric meter. Background Art

[0002] Current electricity meters can only guarantee accuracy within the factory. When used in real-world environments, long periods of operation can cause errors in individual sampling components. This can lead to errors in meter sampling accuracy, but customers often struggle to detect meter anomalies during actual use. In some locations where meter accuracy requirements are stringent, the only option is to periodically replace the meter to verify accuracy.

[0003] Therefore, further improvements are made to the above problems. Summary of the Invention

[0004] The main purpose of the present invention is to provide a self-test feedback method for a three-phase electricity meter. When the accuracy of the three-phase electricity meter is abnormal, the electricity meter can remind the customer through communication, alarm light or buzzer. The customer can replace the electricity meter according to the alarm prompt, and there will be no situation where the electricity meter is still used when the accuracy is out of tolerance.

[0005] To achieve the above objectives, the present invention provides a self-testing and feedback method for a three-phase electric meter, which is used for the three-phase electric meter to perform self-testing and feedback on the sampling accuracy, comprising the following steps:

[0006] Step S1: After receiving a current self-test instruction transmitted by a processor of a three-phase electric meter according to a preset period, the current switching switch at the current end switches the normal current sampling circuit to the current self-test circuit, so that the current self-test circuit detects the current currently inputted by the current end, thereby obtaining current self-test data and transmitting the current self-test data to the processor, so that the processor compares the current sampling data obtained by the normal current sampling circuit with the current self-test data and outputs a current error comparison result to complete the current self-test;

[0007] Step S2: After the voltage switching switch at the voltage end receives the voltage self-test instruction transmitted by the processor of the three-phase electricity meter according to a preset period, the normal voltage sampling circuit is switched to the voltage self-test circuit, so that the voltage self-test circuit detects the voltage currently inputted at the voltage end, thereby obtaining voltage self-test data and transmitting the voltage self-test data to the processor, so that the processor compares the voltage sampling data obtained by the previous normal voltage sampling circuit with the voltage self-test data, and outputs the voltage error comparison result to complete the voltage self-test.

[0008] As a further preferred technical solution of the above technical solution, in step S1:

[0009] After the normal current sampling circuit is switched to the current self-test circuit, the current self-test circuit completes the current self-test within a preset first time (preferably 1s) and the current switching switch switches the current self-test circuit at the current end back to the normal current sampling circuit, wherein:

[0010] If the processor compares the current sampling data with the current self-test data and determines that the current error comparison result is within the preset current error range, the three-phase meter continues to perform current self-test according to the preset cycle;

[0011] If the processor compares the current sampling data with the current self-test data and determines that the current error comparison result is outside the preset current error range, the three-phase electricity meter continues to send a current self-test instruction to the current switching switch according to a preset second time (preferably half an hour), so that the current switching switch continues to switch the normal current sampling circuit to the current self-test circuit, and then the current self-test circuit performs a second current self-test. If the current error comparison results of the current self-test for a preset number of times (preferably three times) are all outside the preset current error range, the processor transmits the generated current replacement instruction to the current switching switch, so that the current self-test circuit replaces the current sampling circuit for current sampling and the processor outputs a current self-test alarm message (thereby reminding that the current sampling circuit has a fault and needs to be replaced). Otherwise, if the current error comparison result of any current self-test in the preset number of times is within the preset current error range, the three-phase electricity meter continues to perform current self-test according to the preset period and the processor outputs a current error alarm message (the cause of the error alarm can be further analyzed to reduce the false alarm rate).

[0012] As a further preferred technical solution of the above technical solution, in step S2:

[0013] After the normal voltage sampling circuit is switched to the voltage self-test circuit, the voltage self-test circuit completes the voltage self-test within a preset first time (preferably 1s) and the voltage switching switch switches the voltage self-test circuit at the voltage end back to the normal voltage sampling circuit, wherein:

[0014] If the processor compares the voltage sampling data with the voltage self-test data and determines that the voltage error comparison result is within the preset voltage error range, the three-phase meter continues to perform voltage self-test according to the preset period;

[0015] If the processor compares the voltage sampling data with the voltage self-test data and determines that the voltage error comparison result is outside the preset voltage error range, the three-phase electricity meter continues to send a voltage self-test instruction to the voltage switching switch according to a preset second time (preferably half an hour), so that the voltage switching switch continues to switch the normal voltage sampling circuit to the voltage self-test circuit, and then the voltage self-test circuit performs a second voltage self-test. If the voltage error comparison results of the voltage self-test for a preset number of times (preferably three times) are all outside the preset voltage error range, the processor transmits the generated voltage replacement instruction to the voltage switching switch, so that the voltage self-test circuit replaces the voltage sampling circuit for voltage sampling and the processor outputs a voltage self-test alarm message (thereby reminding that the current voltage sampling circuit has a fault and needs to be replaced). Otherwise, if the voltage error comparison result of any voltage self-test in the preset number of times is within the preset voltage error range, the three-phase electricity meter continues to perform voltage self-test according to the preset period and the processor outputs a voltage error alarm message (the cause of the error alarm can be further analyzed to reduce the false alarm rate).

[0016] As a further preferred technical solution of the above technical solution, it also includes step S3 (which can be verified together with step S1 and step S2, or verified independently): for the self-check of the calibration parameters, the calibration parameters will be saved and connected to several copies of the test to achieve the self-check effect. The three-phase meter will read the calibration values ​​in the memory at regular intervals, and the read data will have a CRC check. If the data is wrong, the parameters corresponding to the data will be discarded until the correct calibration parameters are read. Then, they are compared with the parameters of the three-phase meter. If it is abnormal, the calibration values ​​of the three-phase meter are updated to update the wrong calibration values ​​to the correct calibration values, and if none of the copies are normal, the calibration parameter self-check alarm information is output.

[0017] As a further preferred technical solution of the above technical solution, the current switching switch is an analog switch, and the voltage switching switch is a relay.

[0018] The beneficial effects of the present invention are:

[0019] 1. Reduce the labor cost of later maintenance and eliminate the need for manual regular inspections.

[0020] 2. When an abnormality occurs in one line and the meter is not replaced in time, the self-detection circuit will replace the normal detection circuit for measurement, reducing the loss of electricity caused by abnormal measurement.

[0021] 3. The self-check circuit performs real-time self-check. If there is no abnormality, there is no need to replace the meter, which increases its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of a self-test feedback method of a three-phase electric meter according to the present invention. DETAILED DESCRIPTION

[0023] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are for illustrative purposes only, and those skilled in the art will readily appreciate other obvious variations. The basic principles of the present invention defined in the following description may be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0024] In the preferred embodiment of the present invention, those skilled in the art should note that the three-phase electric meter and the like involved in the present invention may be regarded as prior art.

[0025] Preferred embodiment.

[0026] The present invention discloses a self-testing and feedback method for a three-phase electric meter, which is used for the three-phase electric meter to perform self-testing and feedback on sampling accuracy, and includes the following steps:

[0027] Step S1: After receiving a current self-test instruction transmitted by a processor of a three-phase electric meter according to a preset period, the current switching switch at the current end switches the normal current sampling circuit to the current self-test circuit, so that the current self-test circuit detects the current currently inputted by the current end, thereby obtaining current self-test data and transmitting the current self-test data to the processor, so that the processor compares the current sampling data obtained by the normal current sampling circuit with the current self-test data and outputs a current error comparison result to complete the current self-test;

[0028] Step S2: After the voltage switching switch at the voltage end receives the voltage self-test instruction transmitted by the processor of the three-phase electricity meter according to a preset period, the normal voltage sampling circuit is switched to the voltage self-test circuit, so that the voltage self-test circuit detects the voltage currently inputted at the voltage end, thereby obtaining voltage self-test data and transmitting the voltage self-test data to the processor, so that the processor compares the voltage sampling data obtained by the previous normal voltage sampling circuit with the voltage self-test data, and outputs the voltage error comparison result to complete the voltage self-test.

[0029] Specifically, in step S1:

[0030] After the normal current sampling circuit is switched to the current self-test circuit, the current self-test circuit completes the current self-test within a preset first time (preferably 1s) and the current switching switch switches the current self-test circuit at the current end back to the normal current sampling circuit, wherein:

[0031] If the processor compares the current sampling data with the current self-test data and determines that the current error comparison result is within the preset current error range, the three-phase meter continues to perform current self-test according to the preset cycle;

[0032] If the processor compares the current sampling data with the current self-test data and determines that the current error comparison result is outside the preset current error range, the three-phase electricity meter continues to send a current self-test instruction to the current switching switch according to a preset second time (preferably half an hour), so that the current switching switch continues to switch the normal current sampling circuit to the current self-test circuit, and then the current self-test circuit performs a second current self-test. If the current error comparison results of the current self-test for a preset number of times (preferably three times) are all outside the preset current error range, the processor transmits the generated current replacement instruction to the current switching switch, so that the current self-test circuit replaces the current sampling circuit for current sampling and the processor outputs a current self-test alarm message (thereby reminding that the current sampling circuit has a fault and needs to be replaced). Otherwise, if the current error comparison result of any current self-test in the preset number of times is within the preset current error range, the three-phase electricity meter continues to perform current self-test according to the preset period and the processor outputs a current error alarm message (the cause of the error alarm can be further analyzed to reduce the false alarm rate).

[0033] More specifically, in step S2:

[0034] After the normal voltage sampling circuit is switched to the voltage self-test circuit, the voltage self-test circuit completes the voltage self-test within a preset first time (preferably 1s) and the voltage switching switch switches the voltage self-test circuit at the voltage end back to the normal voltage sampling circuit, wherein:

[0035] If the processor compares the voltage sampling data with the voltage self-test data and determines that the voltage error comparison result is within the preset voltage error range, the three-phase meter continues to perform voltage self-test according to the preset period;

[0036] If the processor compares the voltage sampling data with the voltage self-test data and determines that the voltage error comparison result is outside the preset voltage error range, the three-phase electricity meter continues to send a voltage self-test instruction to the voltage switching switch according to a preset second time (preferably half an hour), so that the voltage switching switch continues to switch the normal voltage sampling circuit to the voltage self-test circuit, and then the voltage self-test circuit performs a second voltage self-test. If the voltage error comparison results of the voltage self-test for a preset number of times (preferably three times) are all outside the preset voltage error range, the processor transmits the generated voltage replacement instruction to the voltage switching switch, so that the voltage self-test circuit replaces the voltage sampling circuit for voltage sampling and the processor outputs a voltage self-test alarm message (thereby reminding that the current voltage sampling circuit has a fault and needs to be replaced). Otherwise, if the voltage error comparison result of any voltage self-test in the preset number of times is within the preset voltage error range, the three-phase electricity meter continues to perform voltage self-test according to the preset period and the processor outputs a voltage error alarm message (the cause of the error alarm can be further analyzed to reduce the false alarm rate).

[0037] Furthermore, step S3 is also included (which can be verified together with step S1 and step S2, or independently verified): for the self-test of the calibration parameters, the calibration parameters will be saved and connected to several copies of the test to achieve the self-test effect. The three-phase meter will periodically read the calibration values ​​in the memory, and the read data will be CRC-checked. If the data is wrong, the parameters corresponding to the data will be discarded until the correct calibration parameters are read, and then compared with the parameters of the three-phase meter. If it is abnormal, the calibration value of the three-phase meter will be updated to update the wrong calibration value to the correct calibration value, and if none of the copies is normal, the calibration parameter self-test alarm information will be output.

[0038] Furthermore, the current switching switch is an analog switch, and the voltage switching switch is a relay.

[0039] Preferably, for sampling self-test, in addition to the normal working circuits, an additional self-test circuit is added to the current and voltage detection. When the meter is working normally, the self-test circuit will periodically check whether the current and voltage measurement values ​​are correct. When one of the three current or voltage channels is abnormal, it can be detected by the self-test circuit. In order to minimize signal consumption, the self-test circuit at the current end uses an analog switch to switch. At the voltage detection end, since the signal is high voltage, a relay is used to switch the switch.

[0040] For self-checking of calibration parameters, three copies are saved to ensure a complete self-check. The meter periodically reads the calibration values ​​from the EEPROM. The readout data includes a CRC checksum. If the data is incorrect, the copy is discarded. The correct calibration parameters are then compared with the meter parameters. If any are abnormal, the meter calibration values ​​are updated. If neither copy is normal, an alarm is triggered.

[0041] Preferably, the processor can set whether to enable self-test and the self-test interval. The self-test error range can also be set using a button. When the meter reaches the set time, it will begin a voltage and current self-test, which will complete within 1 second. If the error exceeds the error threshold set by the button, the meter will test again after half an hour. If the error threshold is exceeded three times in a row, the meter will trigger an abnormality alarm and the self-test circuit will intervene in the measurement, replacing the abnormal sampling circuit.

[0042] It is worth mentioning that the technical features such as the three-phase electric meter involved in the patent application of this invention should be regarded as prior art. The specific structure, working principle and possible control method and spatial layout method of these technical features can be selected by conventional means in the field and should not be regarded as the inventive point of the patent of this invention. The patent of this invention will not be further elaborated.

[0043] For those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent replacements for some of the technical features therein. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A self-test feedback method for a three-phase electric meter, which is used for the three-phase electric meter to perform self-test feedback on the sampling accuracy, characterized in that: The following steps are involved: Step S1: After receiving a current self-test instruction transmitted by a processor of a three-phase electric meter according to a preset period, the current switching switch at the current end switches the normal current sampling circuit to the current self-test circuit, so that the current self-test circuit detects the current currently inputted by the current end, thereby obtaining current self-test data and transmitting the current self-test data to the processor, so that the processor compares the current sampling data obtained by the normal current sampling circuit with the current self-test data and outputs a current error comparison result to complete the current self-test; Step S2: After receiving a voltage self-test instruction transmitted by the processor of the three-phase electricity meter according to a preset period, the voltage switching switch at the voltage end switches the normal voltage sampling circuit to the voltage self-test circuit, so that the voltage self-test circuit detects the voltage currently inputted at the voltage end, thereby obtaining voltage self-test data and transmitting the voltage self-test data to the processor, so that the processor compares the voltage sampling data obtained by the previously normal voltage sampling circuit with the voltage self-test data and outputs a voltage error comparison result, thereby completing the voltage self-test; In step S1: After the normal current sampling circuit is switched to the current self-test circuit, the current self-test circuit completes the current self-test within a preset first time and the current switching switch switches the current self-test circuit at the current end back to the normal current sampling circuit, wherein: If the processor compares the current sampling data with the current self-test data and determines that the current error comparison result is within the preset current error range, the three-phase meter continues to perform current self-test according to the preset cycle; If the processor compares the current sampling data with the current self-test data and determines that the current error comparison result is outside the preset current error range, the three-phase electricity meter continues to send a current self-test instruction to the current switching switch according to the preset second time, so that the current switching switch continues to switch the normal current sampling circuit to the current self-test circuit, and then the current self-test circuit performs a second current self-test. If the current error comparison results of the current self-tests for a consecutive preset number of times are all outside the preset current error range, the processor transmits the generated current replacement instruction to the current switching switch, so that the current self-test circuit replaces the current sampling circuit for current sampling and the processor outputs a current self-test alarm message. Otherwise, if the current error comparison result of any current self-test in the preset number of times is within the preset current error range, the three-phase electricity meter continues to perform current self-test according to the preset period and the processor outputs a current error alarm message. In step S2: After the normal voltage sampling circuit is switched to the voltage self-test circuit, the voltage self-test circuit completes the voltage self-test within a preset first time and the voltage switching switch switches the voltage self-test circuit at the voltage end back to the normal voltage sampling circuit, wherein: If the processor compares the voltage sampling data with the voltage self-test data and determines that the voltage error comparison result is within the preset voltage error range, the three-phase meter continues to perform voltage self-test according to the preset period; If the processor compares the voltage sampling data with the voltage self-test data and determines that the voltage error comparison result is outside the preset voltage error range, the three-phase electricity meter continues to send a voltage self-test instruction to the voltage switching switch according to the preset second time, so that the voltage switching switch continues to switch the normal voltage sampling circuit to the voltage self-test circuit, and then the voltage self-test circuit performs a second voltage self-test. If the voltage error comparison results of the voltage self-tests for a consecutive preset number of times are all outside the preset voltage error range, the processor transmits the generated voltage replacement instruction to the voltage switching switch, so that the voltage self-test circuit replaces the voltage sampling circuit for voltage sampling and the processor outputs a voltage self-test alarm message. Otherwise, if the voltage error comparison result of any of the preset number of voltage self-tests is within the preset voltage error range, the three-phase electricity meter continues to perform voltage self-test according to the preset period and the processor outputs a voltage error alarm message. It also includes step S3: for the self-check of the calibration parameters, the calibration parameters will be saved and connected to several copies of the test to achieve the self-check effect. The three-phase meter will read the calibration values ​​in the memory at regular intervals, and the read data will have a CRC check. If the data is wrong, the parameters corresponding to the data will be discarded until the correct calibration parameters are read. They are compared with the parameters of the three-phase meter. If there is an abnormality, the calibration value of the three-phase meter is updated to update the incorrect calibration value to the correct calibration value, and if none of the copies are normal, the calibration parameter self-check alarm information is output.

2. The self-test feedback method of a three-phase electric meter according to claim 1, characterized in that: The current switching switch is an analog switch, and the voltage switching switch is a relay.

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