阅读说明：本技术 一种高压分压器的期间核查方法及装置 (Period checking method and device for high-voltage divider ) 是由 邱育林 王超 王铎 胡永雄 赵坤 董岳 于 2020-10-28 设计创作，主要内容包括：本发明涉及一种高压分压器的期间核查方法及装置,通过在两次校准期间内核查高压分压器,使其测量结果保持良好的可信度；而且该方法是利用低电压等级分压器对高压分压器进行期间核查,操作方便、易于实施。(The invention relates to a period checking method and a device of a high-voltage divider, which are used for checking the high-voltage divider in two calibration periods so that the measuring result keeps good credibility; in addition, the method utilizes the low-voltage grade voltage divider to carry out period check on the high-voltage divider, and is convenient to operate and easy to implement.)

1. A method for duration checking of a high voltage divider, comprising the steps of:

determining a checking point of the high-voltage divider to be checked;

connecting the high-voltage divider to be checked and the standard voltage divider in parallel through a lead, connecting the high-voltage end of the voltage divider connected in parallel into the output end of the voltage generator through the lead, and applying voltage to obtain measured voltage data;

and comparing the measured voltage data with the checking criterion, wherein if each checking point accords with the checking criterion, the checking is passed, and otherwise, the checking is not passed.

2. The method of claim 1, wherein the check points comprise real and dead reckoning points; wherein the content of the first and second substances,

the determination of the actual measurement points comprises the steps of selecting three voltages with different levels from low to high at equal intervals as the actual measurement points within the range of the standard voltage divider;

the determination of the calculation point comprises the steps of sequentially selecting three voltages with different levels at equal intervals as the calculation point from a voltage value higher than the range of the standard voltage divider.

3. The method of claim 2, wherein the range of the standard voltage divider is greater than or equal to 20% of the range of the high voltage divider to be checked.

4. The method according to claim 3, wherein if the high voltage divider to be checked is a surge voltage divider, 5 times of surge voltage are applied to each positive and negative polarity of the check point, and the peak voltage value is recorded.

5. The method according to claim 3, wherein if the high voltage divider to be checked is a DC voltage divider, after the voltage at each check point is stabilized, 5 times of voltage data are recorded, and the steps are repeated in the reverse polarity.

6. The method according to claim 3, characterized in that if the high voltage divider to be checked is an AC voltage divider, the effective value of the voltage is recorded 5 times after the voltage is stabilized at each check point.

7. The method of claim 2, further comprising estimating a voltage value of the estimated point of the high voltage divider to be checked according to the following estimation formula based on the voltage data measured at the measured point:

y＝Ax²+Bx+C

wherein y is the voltage value of the high voltage divider to be checked, x is the voltage value of the standard voltage divider, and A, B, C is the calculation coefficient.

8. The method of claim 1, wherein the verification criteria comprises:

y is the average value of the voltage value of the high-voltage divider to be checked at the checking point, X is the average value of the voltage value of the standard voltage divider at the corresponding checking point, E is the maximum allowable error of the high-voltage divider to be checked, and U is the measurement uncertainty of the standard voltage divider.

9. The device for checking the period of the high-voltage divider is characterized by comprising a checking point determining module, a voltage data measuring module and a checking criterion comparing module; wherein the content of the first and second substances,

the checking point determining module is used for determining the checking point of the high-voltage divider to be checked;

the voltage data measuring module is used for connecting the high-voltage divider to be checked and the standard voltage divider in parallel through a lead, connecting the high-voltage end of the voltage divider connected in parallel into the output end of the voltage generator through the lead and applying voltage to obtain measured voltage data;

the checking criterion comparing module compares the measured voltage data with the checking criterion, and if each checking point accords with the checking criterion, the checking is passed, otherwise, the checking is not passed.

10. The apparatus of claim 9, wherein the check points comprise real points and dead points; wherein the content of the first and second substances,

the determination of the actual measurement points comprises the steps of selecting three voltages with different levels from low to high at equal intervals as the actual measurement points within the range of the standard voltage divider;

the determination of the calculation point comprises the steps of sequentially selecting three voltages with different levels at equal intervals as the calculation point from a voltage value higher than the range of the standard voltage divider.

Technical Field

The invention relates to the technical field of calibration, verification and detection of power equipment, in particular to a period checking method and device of a high-voltage divider.

Background

The purpose of the duration check is to ensure that the device remains stable, in good condition and with high confidence in the measurement between two calibrations. There are many methods for period checking, and the checking criteria are various, but there is no period checking method available for the high voltage divider. The difficulty of checking during high voltage divider is:

(1) one laboratory is often provided with only one high-voltage divider of the same type, and two high-voltage dividers of the same type with the same voltage level can not be subjected to comparison experiments during checking;

(2) the high voltage divider is checked for duration using a third party calibration laboratory, which is too costly to check.

Disclosure of Invention

Based on the above situation in the prior art, an object of the present invention is to provide a simple method for checking the period of a high voltage divider, so as to keep good reliability of the measurement result and reduce the checking cost.

To achieve the above object, according to one aspect of the present invention, there is provided a duration checking method of a high voltage divider, comprising the steps of:

determining a checking point of the high-voltage divider to be checked;

connecting the high-voltage divider to be checked and the standard voltage divider in parallel through a lead, connecting the high-voltage end of the voltage divider connected in parallel into the output end of the voltage generator through the lead, and applying voltage to obtain measured voltage data;

and comparing the measured voltage data with the checking criterion, wherein if each checking point accords with the checking criterion, the checking is passed, and otherwise, the checking is not passed.

Further, the check points comprise actual measuring points and calculated points; wherein the content of the first and second substances,

the determination of the actual measurement points comprises the steps of selecting three voltages with different levels from low to high at equal intervals as the actual measurement points within the range of the standard voltage divider;

the determination of the calculation point comprises the steps of sequentially selecting three voltages with different levels at equal intervals as the calculation point from a voltage value higher than the range of the standard voltage divider.

Further, the range of the standard voltage divider is greater than or equal to 20% of the range of the high-voltage divider to be checked.

Further, if the high voltage divider to be checked is an impulse voltage divider, impulse voltage is applied to each positive polarity and negative polarity of the check point for 5 times.

Further, if the high voltage divider to be checked is a direct current voltage divider, after the voltage of each check point is stable, 5 times of voltage data are recorded, and the steps are repeated with the opposite polarity.

Further, if the high-voltage divider to be checked is an alternating-current voltage divider, recording the effective value of the voltage for 5 times after the voltage of each check point is stable.

Further, the method also comprises the step of calculating the voltage value of the calculated point of the high-voltage divider to be checked according to the following calculation formula according to the voltage data measured by the measured point:

y＝Ax²+Bx+C

wherein y is the voltage value of the high voltage divider to be checked, x is the voltage value of the standard voltage divider, and A, B, C is the calculation coefficient.

Further, the checking criteria include:

y is the average value of the voltage value of the high-voltage divider to be checked at the checking point, X is the average value of the voltage value of the standard voltage divider at the corresponding checking point, E is the maximum allowable error of the high-voltage divider to be checked, and U is the measurement uncertainty of the standard voltage divider.

According to another aspect of the invention, the device for checking the period of the high-voltage divider is improved, and comprises a checking point determining module, a voltage data measuring module and a checking criterion comparing module; wherein the content of the first and second substances,

the checking point determining module is used for determining the checking point of the high-voltage divider to be checked;

the voltage data measuring module is used for connecting the high-voltage divider to be checked and the standard voltage divider in parallel through a lead, connecting the high-voltage end of the voltage divider connected in parallel into the output end of the voltage generator through the lead and applying voltage to obtain measured voltage data;

the checking criterion comparing module compares the measured voltage data with the checking criterion, and if each checking point accords with the checking criterion, the checking is passed, otherwise, the checking is not passed.

Further, the check points comprise actual measuring points and calculated points; wherein the content of the first and second substances,

the determination of the actual measurement points comprises the steps of selecting three voltages with different levels from low to high at equal intervals as the actual measurement points within the range of the standard voltage divider;

the determination of the calculation point comprises the steps of sequentially selecting three voltages with different levels at equal intervals as the calculation point from a voltage value higher than the range of the standard voltage divider.

In summary, the present invention provides a period checking method and apparatus for a high voltage divider, which maintain good reliability of the measurement result by checking the high voltage divider during two calibration periods; in addition, the method utilizes the low-voltage grade voltage divider to carry out period check on the high-voltage divider, and is convenient to operate and easy to implement.

Drawings

FIG. 1 is a flow chart of a method for period checking of a high voltage divider of the present invention;

FIG. 2 is a schematic diagram of the connection between the high voltage divider to be checked and the standard voltage divider according to the present invention;

fig. 3 is a schematic diagram of the overall structure of the period checking device of the high voltage divider according to the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

The technical solution of the present invention will be described in detail below with reference to the accompanying drawings. According to an embodiment of the present invention, a method for checking the duration of a high voltage divider is provided, and the flow chart of the method is shown in fig. 1. The method comprises the following steps:

and determining a checking point of the high-voltage divider to be checked. The high-voltage divider to be checked refers to a voltage divider needing to be checked during the period, and the range of the voltage divider is too large to carry out full-range measurement. In the embodiment, the high-voltage divider is checked in a period by adopting a standard voltage divider, the standard voltage divider is a voltage divider qualified by calibration of a third party calibration unit with related qualification, and the range of the standard voltage divider can only cover one part of the voltage divider to be checked. The range of the standard voltage divider can be smaller than the range of the voltage divider to be checked, but must be greater than or equal to 20% of the range of the voltage divider to be checked.

And connecting the high-voltage divider to be checked and the standard voltage divider in parallel through a lead, connecting the high-voltage end of the voltage divider connected in parallel into the output end of the voltage generator through the lead, and applying voltage to obtain measured voltage data. The connection between the high voltage divider to be checked and the standard voltage divider is schematically shown in fig. 2. The high voltage divider to be checked may include a surge voltage divider, a dc high voltage divider, and an ac high voltage divider. If the high-voltage divider to be checked is the impulse voltage divider, the top voltage-sharing cover of the high-voltage divider to be checked is connected with the top voltage-sharing cover of the standard impulse voltage divider by using a wide copper sheet. If the high-voltage divider to be checked is a direct-current high-voltage divider, the top voltage-sharing cover of the high-voltage divider to be checked is connected with the top voltage-sharing cover of the standard direct-current voltage divider by a corrugated pipe. If the high-voltage divider to be checked is an alternating-current high-voltage divider, the top voltage-sharing cover of the high-voltage divider to be checked is connected with the top voltage-sharing cover of the standard alternating-current voltage divider by a corrugated pipe. After the voltage is applied, the voltage values measured by the two groups of voltage dividers are recorded simultaneously to obtain measured voltage data. The checking point is a set voltage value for checking and comparing the high-voltage divider to be checked and is divided into an actual measuring point and a calculated point, and the setting mode is as follows: selecting three voltage values at equal intervals in the range of the standard voltage divider as real measuring points to be checked, and selecting three voltage values at equal intervals from the upper limit of the range of the standard voltage divider as calculated points to be checked; if the high-voltage divider to be checked is an impulse voltage divider, impulse voltage is applied to the positive polarity and the negative polarity of each check point for 5 times respectively, and the voltage value is taken as a peak value; if the high-voltage divider to be checked is a direct-current voltage divider, recording voltage data for 5 times after the voltage of each point to be checked is stable, and repeating the step with the opposite polarity; if the voltage divider to be checked is an alternating current voltage divider, recording the effective value of the voltage for 5 times after the voltage of each check point is stabilized.

Preferably, the voltage value of the calculated point of the high-voltage divider to be checked is calculated according to the data of the three checking actual measuring points; in each checking point, the voltage value of each group of high-voltage dividers to be checked has a one-to-one correspondence with the voltage value of one group of standard voltage dividers, and the set correspondence is as follows:

y＝Ax²+Bx+C

wherein y is the voltage value of the voltage divider to be checked, x is the voltage value of the standard voltage divider, A, B, C is a calculation coefficient, and three coefficients A, B, C can be calculated by substituting the data of x and y at three actual measurement points into a corresponding relation; then, according to the above formula and the x value at the predetermined calculation point, the calculation voltage value y of the high voltage divider to be checked corresponding to the voltage value of each standard voltage divider can be calculated.

The measured voltage data is compared with a checking criterion, when the checking result meets the criterion requirement, the checking is passed, the measuring result of the high-voltage divider has better credibility, and the checking criterion can be set as follows:

y is the average value of the voltage value of the high-voltage divider to be checked at the checking point, X is the average value of the voltage value of the standard voltage divider at the corresponding checking point, E is the maximum allowable error of the high-voltage divider to be checked, and U is the measurement uncertainty of the standard voltage divider; where E is derived from the relevant standard or specification and U is derived from the calibration certificate of the standard voltage divider.

When the checking result does not meet the requirement of the criterion, the checking is not passed, and the high-voltage divider needs to be calibrated by a third-party calibration laboratory to confirm whether the high-voltage divider can be used continuously.

The specific process of the period checking method is described below by taking the period checking of a 3000kV impulse voltage divider and taking the standard voltage divider as a 1000kV impulse voltage divider as an example.

S1, checking the real measuring points to be +/-350 kV, + -550 kV, + -750 kV, and checking the reckoning points to be +/-1500 kV, + -2000 kV, + -2500 kV;

and S2, connecting the high-voltage divider to be checked and the standard voltage divider in parallel through a lead and then connecting the high-voltage divider to the voltage output end of the impulse voltage generator.

And S3, starting the impulse voltage generator, and recording the voltage values measured by the two voltage dividers.

S4, positive polarity check data are shown in table 1.

TABLE 1 Positive polarity Voltage data

And S5, processing data, and calculating the average value of the voltage values measured at each check point, wherein the average value of the voltage values at each check point is shown in Table 2.

TABLE 2 mean values of the voltage values

Checking point	Standard voltage divider measurement kV	To-be-checked voltage divider measurement result kV
			1	324.56	321.32
2	552.28	545.98
			3	760.58	752.56

Setting the corresponding relation between the measurement result of the voltage divider to be checked and the measurement result of the standard voltage divider as follows:

y＝Ax²+Bx+C

from three sets of voltage averages out of 3 check points, one can calculate:

A＝1.19×10-5，B＝0.976，C＝3.25

the corresponding relation between the voltage divider to be checked and the measurement result of the standard voltage divider is as follows:

y＝1.19×10^-5x²+0.976x+3.25

according to the relation, the voltage of each estimated point of the voltage divider to be checked is estimated, and the voltage value of each estimated point is shown in table 3.

TABLE 3 Voltage values at respective estimated points

And S6, substituting the check point data into the check standard for calculation. The processing results of the positive polarity data are shown in table 4.

TABLE 4 Positive polarity data processing results

And E is the maximum allowable error of the high-voltage divider to be checked, and the value of U is derived from a calibration report of a standard voltage divider.

S7, reversing the polarity of the generator, and checking the negative polarity: steps S3-S6 were repeated, and the measured data was processed as shown in Table 5.

TABLE 5 negative polarity data processing results

According to the analysis of the data processing results in tables 4 and 5, the checking data of the high-voltage divider to be checked at all the checking points all meet the criterion requirement, so that the divider to be checked passes the checking in the period.

According to another embodiment of the invention, a period checking device of a high-voltage divider is provided, and the overall structure of the device is schematically shown in fig. 3, and the device comprises a checking point determining module, a voltage data measuring module and a checking criterion comparing module. And the checking point determining module is used for determining the checking point of the high-voltage divider to be checked. The voltage data measuring module connects the high-voltage divider to be checked and the standard voltage divider in parallel through a lead, and connects the high-voltage end of the voltage divider connected in parallel to the output end of the voltage generator through the lead and applies voltage to obtain measured voltage data. The checking criterion comparing module compares the measured voltage data with the checking criterion, and if each checking point accords with the checking criterion, the checking is passed, otherwise, the checking is not passed. The check points comprise actual measuring points and calculation points; the determination of the actual measurement point comprises the steps of selecting three voltages with different levels from low to high at equal intervals as the actual measurement point within the range of the standard voltage divider; the calculation point determination comprises the steps of sequentially selecting three voltages with different levels at equal intervals from a voltage value higher than the range of the standard voltage divider as the calculation point.

In summary, the present invention relates to a period checking method and apparatus for a high voltage divider, which maintain good reliability of the measurement result by checking the high voltage divider during two calibration periods; in addition, the method utilizes the low-voltage grade voltage divider to carry out period check on the high-voltage divider, and is convenient to operate and easy to implement.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.