Disclosure of Invention
The invention aims to provide a metering supervision method for an automatic verification assembly line of a low-voltage current transformer, which is used for automatically checking the automatic verification assembly line.
The invention provides a metering supervision method for an automatic verification assembly line of a low-voltage current transformer, which comprises the following steps:
a, providing a standard mutual inductor;
b, repeatedly testing the standard mutual inductor under a first metering standard to obtain a first error mean value epsilon1And a first measurement extension uncertainty U1;
C: repeatedly testing the standard mutual inductor under a second metering standard to obtain a second error mean value epsilon2And a second measurement spread uncertainty U2The second metering standard is a metering standard applicable to the automatic verification assembly line of the low-voltage current transformer, and the grade of the second metering standard is lower than that of the first metering standard;
d: according to the first error mean value epsilon1First measurement expansion uncertainty U1Second mean error ε2And a second measurement spread uncertainty U2Calculating to obtain a capacity value En of the automatic verification assembly line of the low-voltage current transformer, if the absolute value of the capacity value En is greater than 1, the automatic verification assembly line of the low-voltage current transformer is not applicable to the metering and monitoring method, if the absolute value of the capacity value En is less than or equal to 1, the automatic verification assembly line of the low-voltage current transformer is applicable to the metering and monitoring method, and entering the next step;
e: repeatedly testing the standard transformer under a second metering standard to obtain error data of the standard transformer, and obtaining a standard deviation according to the error data;
f: detecting the standard transformer by using the automatic verification assembly line of the low-voltage current transformer to obtain an actual measurement error;
g: and judging whether the automatic verification assembly line of the low-voltage current transformer is normal or not according to the actual measurement error and the standard deviation.
Further, in the step C and the step E, the number of times of repeated tests is more than or equal to 10, and the time interval between two adjacent tests is 1 day.
Further, in the step D, a capability value En of the automatic verification assembly line of the low-voltage current transformer is calculated according to the following formula:
further, in the step G, the specific determination method is:
if the absolute value of the actual measurement error is smaller than the standard deviation, judging that the automatic verification assembly line of the low-voltage current transformer is normal;
and if the absolute value of the actual measurement error is larger than the standard deviation, the standard transformer is tested repeatedly under the first metering standard, if the standard transformer is normal, the automatic verification assembly line fault of the low-voltage current transformer is judged, if the standard transformer is in fault, a new standard transformer is replaced, and the step F and the step G are repeated.
Further, the accuracy grade of the standard mutual inductor is 0.05S grade.
The metering supervision method for the automatic verification assembly line of the low-voltage current transformer provided by the invention uses the verified standard transformer to automatically detect the low-voltage current transformer, thereby realizing the purpose of automatic verification.
Detailed Description
The present invention is further described below in conjunction with specific examples to enable those skilled in the art to better understand the present invention and to practice it, but the examples are not intended to limit the present invention.
The invention provides a metering supervision method for an automatic verification assembly line of a low-voltage current transformer, which is characterized by comprising the following steps of:
a, providing a standard transformer which has excellent stability, high sensitivity, enough resolution and certain accuracy, meets the requirement of the technical specification of a low-voltage current transformer for metering in the overall dimension and can select the accuracy grade to be 0.05S grade;
b, repeatedly testing the standard transformer under a first metering standard, wherein the times of repeated testing are more than or equal to 10 times, and the time interval of two adjacent tests is 1 day, obtaining a database of the measurement errors of the standard transformer (later-stage verification standard transformer), and obtaining a first error mean value epsilon1And a first measurement extension uncertainty U1;
C: repeating the test on the standard transformer under a second metering standard, for example, 10 times, to obtain a second error mean value epsilon2And a second measurement spread uncertainty U2The second metering standard is a metering standard applicable to the automatic verification assembly line of the low-voltage current transformer, and the grade of the second metering standard is lower than that of the first metering standard;
d: calculating to obtain a capacity value En of the automatic verification assembly line of the low-voltage current transformer according to the following formula:
wherein epsilon1Is the mean value of the first error, U1Extending the uncertainty, ε, for the first measurement2Is the second mean error value, U2Extending the uncertainty for the second measurement;
if the absolute value of the capability value En is larger than 1, the automatic verification assembly line of the low-voltage current transformer is not applicable to the metering and monitoring method, and if the absolute value of the capability value En is smaller than or equal to 1, the automatic verification assembly line of the low-voltage current transformer is applicable to the metering and monitoring method, and the next step is carried out;
e: repeatedly testing the standard transformer under a second metering standard, wherein the times of repeated testing are more than or equal to 10 times, and the time interval between two adjacent tests is 1 day, acquiring error data of the standard transformer, and acquiring a standard deviation according to the error data;
f: detecting the standard transformer by using the automatic verification assembly line of the low-voltage current transformer to obtain an actual measurement error;
g: and judging whether the automatic verification assembly line of the low-voltage current transformer is normal or not according to the actual measurement error and the standard deviation, wherein the specific judgment method comprises the following steps:
if the absolute value of the actual measurement error is smaller than the standard deviation, judging that the automatic verification assembly line of the low-voltage current transformer is normal;
and if the absolute value of the actual measurement error is larger than the standard deviation, the standard transformer is tested repeatedly under the first metering standard, if the standard transformer is normal, the automatic verification assembly line fault of the low-voltage current transformer is judged, if the standard transformer is in fault, a new standard transformer is replaced, and the step F and the step G are repeated.
In the scheme, the standard transformers can be circulated once on the production line after each batch, manual sampling inspection and rechecking are not required, and manpower and material resources input by quality supervision and management departments are reduced;
at present, when a problem system on a certain link on a production line has a wrong response, a large quantity of problem products possibly pass through the production line to finish verification, the method of the scheme can solve the problem that the traditional manual supervision and management mode has hysteresis, even if the problem exists, the problem products only need to be locked in one batch, and a large quantity of unqualified products cannot flow into the market;
the standard mutual inductor database is established, so that the standard mutual inductor database is convenient to call and check in the future management, calibration and checking, the running state of the assembly line can be checked through the standard mutual inductor at any time, and meanwhile paperless archive management can be realized.
The scope of the invention is not limited thereto. The equivalent substitution or change made by the technical personnel in the technical field on the basis of the invention is all within the protection scope of the invention. The protection scope of the invention is subject to the claims.