A method and device for calculating the equivalent salt density of insulator salt spray

Abstract

A method and device for calculating the equivalent salt spray density of insulators, relating to the technical field of power system insulators, involves flushing an unknown amount of salt spray droplets on the insulator surface into a known volume of deionized water to form a wash water. An estimated value for the equivalent salt spray density is derived based on the conductivity of the wash water. The initial deionized water conductivity is subtracted from the final wash water conductivity to reduce offset errors. Errors in the current empirical formula are corrected to propose a new method for calculating the equivalent salt spray density. The new method also undergoes nonlinear correction. This method addresses the technical issue of the inability to accurately calculate the equivalent salt spray density when studying the effect of salt spray conductivity on the surface salt density of insulators. It also corrects the applicable scope of the existing calculation method for the equivalent salt spray density, thereby optimizing the formula for predicting the 50% flashover voltage of the insulator.

Description

Technical Field

[0001] The present invention relates to the technical field of power system insulators, and in particular to a method and device for calculating the salt spray equivalent salt density of an insulator. Background Art

[0002] Insulators are a crucial component of transmission lines. In salt spray environments, the insulator surface becomes moist, forming a water film that increases leakage current. Furthermore, salt in the spray deposits on the insulator surface, increasing the surface salt density, leading to discharge and even flashover. The 50% flashover voltage of an insulator can be predicted based on the surface salt density. In insulator salt spray flashover testing, the surface salt density includes the pre-contamination salt density and the salt spray equivalent salt density. The pre-contamination salt density is predetermined, while the salt spray equivalent salt density is difficult to quantify. Therefore, to optimize the formula for predicting the 50% flashover voltage of an insulator during salt spray testing, it is necessary to calculate the salt spray equivalent salt density.

[0003] At present, the prediction formulas of equivalent salt density for 50% flashover voltage of insulators are mostly based on the fitting of several test data. There is no mature calculation method for equivalent salt density. Summary of the Invention

[0004] To overcome the shortcomings of the above technologies, the present invention provides a method and device for calculating the equivalent salt spray density of insulators, which effectively solves the problem in the prior art of lacking the calculation of the equivalent salt spray density of insulators. The technical solution adopted by the present invention to overcome the technical problem is as follows:

[0005] A method for calculating the equivalent salt density of insulator salt spray includes the following steps:

[0006] S1. Through the formula Calculate the equivalent salt density ESDD1 of the salt spray on the insulator surface, where γ is the measured conductivity of the washing water, V is the volume of the washing water, S is the surface area of ​​the insulator, and γ eq The equivalent conductivity of 1g of NaCl dissolved in 1L of water at 20℃;

[0007] S2. Calculate the equivalent salt density ESDD2 on the insulator surface to reduce the offset error based on the formula for the equivalent salt density ESDD1 on the insulator surface;

[0008] S3. Calculate the corrected salt spray equivalent salt density ESDD3 and the corrected salt spray equivalent salt density ESDD4 for the pre-configured salt spray solution;

[0009] S4. Calculate the equivalent salt density ESDD5 of the salt spray after nonlinear correction and the equivalent salt density ESDD6 of the salt spray after nonlinear correction when the salt spray is a pre-configured salt spray solution.

[0010] Furthermore, in step S2, the formula The equivalent salt density ESDD2 of the insulator surface salt spray that reduces the offset error is calculated, where γ b is the conductivity of the final washing water, γ a is the conductivity of the initial deionized water.

[0011] Furthermore, in step S3, the formula The corrected salt spray equivalent salt density ESDD3 is calculated, where T w is the washing water temperature, γ b ' is the washing water temperature T w The conductivity of the final wash water at a ' is the washing water temperature T w is the conductivity of the initial deionized water at , and C is the temperature coefficient.

[0012] Furthermore, in step S3, the formula The calculated salt spray is the corrected salt spray equivalent salt density ESDD4 of the pre-configured salt spray solution, where γ′ is the washing water temperature T w The conductivity of the pre-prepared salt spray solution at .

[0013] Preferably, C=0.02.

[0014] Furthermore, in step S4, the formula

[0015]

[0016] The equivalent salt density ESDD5 of salt spray after nonlinear correction is calculated.

[0017] Furthermore, in step S4, the formula

[0018]

[0019] The calculated salt spray is the equivalent salt density ESDD6 of the pre-configured salt spray solution after nonlinear correction.

[0020] An insulator salt spray equivalent salt density calculation device, characterized by comprising:

[0021] at least one processor, and

[0022] a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to:

[0023] By formula Calculate the equivalent salt density ESDD1 of the salt spray on the insulator surface, where γ is the measured conductivity of the washing water, V is the volume of the washing water, S is the surface area of ​​the insulator, and γ eq The equivalent conductivity of 1g of NaCl dissolved in 1L of water at 20℃;

[0024] Calculate the equivalent salt density ESDD2 of the insulator surface salt spray that reduces the offset error according to the formula of the equivalent salt density ESDD1 of the insulator surface salt spray;

[0025] Calculate the corrected equivalent salt density of salt spray ESDD3 and the corrected equivalent salt density of salt spray ESDD4 when the salt spray is a pre-configured salt spray solution;

[0026] Calculate the equivalent salt density ESDD5 of the salt spray after nonlinear correction and the equivalent salt density ESDD6 of the salt spray after nonlinear correction when the salt spray is a pre-configured salt spray solution.

[0027] The present invention has the following beneficial effects: An unknown amount of salt spray droplets on the insulator surface is flushed into a known volume of deionized water to form wash water, and an estimate of the equivalent salt density of the salt spray is derived based on the conductivity of the wash water; the initial deionized water conductivity is subtracted from the final wash water conductivity to reduce offset errors; errors in the current empirical formula are corrected to propose a new method for calculating the equivalent salt density of salt spray; and nonlinear correction is performed on the new method. This method solves the technical problem of the inability to accurately calculate the equivalent salt density of salt spray when studying the effect of salt spray conductivity on the salt density of insulator surfaces. It also corrects the applicable scope of the existing calculation method for the equivalent salt density of salt spray, thereby optimizing the prediction formula for the 50% flashover voltage of the insulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Flowchart of the calculation method of the present invention. DETAILED DESCRIPTION

[0029] The following is combined with Figure 1 The present invention is further described.

[0030] A method for calculating the equivalent salt density of insulator salt spray includes the following steps:

[0031] S1. Rinse the unknown amount of salt spray droplets on the insulator surface into a known volume of deionized water to form washing water. According to the conductivity of the washing water, the estimated value of the salt spray equivalent salt density is obtained. Specifically, the formula Calculate the equivalent salt density ESDD1 of the insulator surface salt spray in g / m 2, where if the salt spray is generated by a pre-configured salt spray solution, γ is the measured conductivity of the washing water in μS / cm, V is the volume of the washing water in L, and S is the surface area of ​​the insulator in m 2 , γ eq The equivalent conductivity of 1g of NaCl dissolved in 1L of water at 20°C is 1820μS·L / cm·g.

[0032] S2. Calculate the equivalent salt spray density ESDD2 on the insulator surface that reduces the offset error based on the formula for the equivalent salt spray density ESDD1 on the insulator surface.

[0033] S3. Calculate the corrected equivalent salt density of salt spray ESDD3 and the corrected equivalent salt density of salt spray ESDD4 when the salt spray is a pre-configured salt spray solution.

[0034] S4. Calculate the equivalent salt density ESDD5 of the salt spray after nonlinear correction and the equivalent salt density ESDD6 of the salt spray after nonlinear correction when the salt spray is a pre-configured salt spray solution.

[0035] The problem of mismatch between the applicable scope of the current empirical formula and the actual test value is solved; the error is reduced by subtracting the initial deionized water conductivity from the final washing water conductivity, thereby improving the calculation accuracy; and the scope of application of the salt spray equivalent salt density calculation method is expanded through nonlinear correction.

[0036] In one embodiment of the present invention, in step S2, the conductivity of the final washing water is subtracted from the conductivity of the initial deionized water to reduce the offset error. Specifically, the formula The equivalent salt density ESDD2 of the insulator surface salt spray that reduces the offset error is calculated, where γ b is the conductivity of the final washing water, in μS / cm, γ a is the conductivity of the initial deionized water, in μS / cm. If the salt spray is generated by a pre-configured salt spray solution, no γ correction is required.

[0037] In one embodiment of the present invention, the γ fitted according to current technical experience is eq The value of salt spray density is converted into the standard unit mg / m 2 , the expression of salt spray equivalent salt density is The current technical empirical formula is only applicable when the concentration of the washing water solution is high, that is, when the concentration of the washing water solution is 10-100g / L. When the concentration of the washing water solution is low, the error between the insulator surface salt spray equivalent salt density calculated by this formula and the actual value is large. Therefore, it is necessary to revise the calculation method of the insulator salt spray equivalent salt density to expand its scope of application. Specifically, in step S3, the formula The corrected salt spray equivalent salt density ESDD3 is calculated, where T w is the washing water temperature, γ b ' is the washing water temperature T w The conductivity of the final wash water at a ' is the washing water temperature T w The conductivity of the initial deionized water at 1 ℃ is 0.02, and C is the temperature coefficient. In this embodiment, preferably, C=0.02.

[0038] If the salt spray is generated by a pre-configured salt spray solution, γ′ represents the temperature T w When the conductivity of the solution is prepared, the expression of the salt spray equivalent salt density should be In one embodiment of the present invention, in step S3, the formula The calculated salt spray is the corrected salt spray equivalent salt density ESDD4 of the pre-configured salt spray solution.

[0039] This calculation method can realize the calculation of the equivalent salt density of insulator salt spray in a certain concentration range of washing water solution, but there is still room for optimization.

[0040] In one embodiment of the present invention, the expression of salt spray equivalent salt density has a small deviation when the concentration of the washing solution is low, but experimental calculations show that appropriate nonlinear correction can provide about 10% improvement at higher concentrations. Therefore, in step S4, the formula

[0041]

[0042] The equivalent salt density ESDD5 of salt spray after nonlinear correction is calculated. In step S4, the formula

[0043] The calculated salt spray equivalent salt density ESDD6 is the nonlinear correction of the pre-configured salt spray solution. Through nonlinear correction, the equivalent salt spray density of the insulator can be calculated with a larger range and smaller deviation. Taking the XWP2-160 insulator as an example, its surface area is 2750cm 2 If the salt mist is not generated by a pre-configured solution, first measure the conductivity of deionized water, then rinse an unknown amount of salt mist droplets on the insulator surface into a known volume of deionized water to form washing water, and measure the conductivity of the final washing water. If the salt mist is generated by a pre-configured salt mist solution, the conductivity of the salt mist solution is recorded as γ'. In this embodiment, (γ b ′-γ a') or γ' is 100μS / cm, the washing water or salt spray solution temperature is 25℃, and the washing water or salt spray solution volume is 1L. Substituting the above values ​​into the two formulas in step S4, the calculated salt spray equivalent salt density on the insulator surface is 164.41mg / m 2 .

[0044] The present invention also relates to an insulator salt spray equivalent salt density calculation device, characterized in that it comprises: at least one processor, and

[0045] a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to:

[0046] By formula Calculate the equivalent salt density ESDD1 of the salt spray on the insulator surface, where γ is the measured conductivity of the washing water, V is the volume of the washing water, S is the surface area of ​​the insulator, and γ eq The equivalent conductivity of 1g of NaCl dissolved in 1L of water at 20℃;

[0047] Calculate the equivalent salt density ESDD2 of the insulator surface salt spray that reduces the offset error according to the formula of the equivalent salt density ESDD1 of the insulator surface salt spray;

[0048] Calculate the corrected equivalent salt density of salt spray ESDD3 and the corrected equivalent salt density of salt spray ESDD4 when the salt spray is a pre-configured salt spray solution;

[0049] Calculate the equivalent salt density ESDD5 of the salt spray after nonlinear correction and the equivalent salt density ESDD6 of the salt spray after nonlinear correction when the salt spray is a pre-configured salt spray solution.

[0050] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for calculating the equivalent salt density of insulator salt spray, characterized in that: The steps include: S1. Through the formula Calculate the equivalent salt density ESDD1 of the salt spray on the insulator surface, where γ is the measured conductivity of the washing water, V is the volume of the washing water, S is the surface area of ​​the insulator, and γ eq The equivalent conductivity of 1g of NaCl dissolved in 1L of water at 20℃; S2. Calculate the equivalent salt density ESDD2 on the insulator surface to reduce the offset error based on the formula for the equivalent salt density ESDD1 on the insulator surface; S3. Calculate the corrected salt spray equivalent salt density ESDD3 and the corrected salt spray equivalent salt density ESDD4 for the pre-configured salt spray solution; S4. Calculate the equivalent salt density ESDD5 of the salt spray after nonlinear correction and the equivalent salt density ESDD6 of the salt spray after nonlinear correction when the salt spray is a pre-configured salt spray solution.

2. The method for calculating the equivalent salt density of insulator salt spray according to claim 1, characterized in that: In step S2, the formula The equivalent salt density ESDD2 of the insulator surface salt spray that reduces the offset error is calculated, where γ b is the conductivity of the final washing water, γ a is the conductivity of the initial deionized water.

3. The method for calculating the equivalent salt density of insulator salt spray according to claim 1, characterized in that: In step S3, the formula The corrected salt spray equivalent salt density ESDD3 is calculated, where T w is the washing water temperature, γ b ' is the washing water temperature T w The conductivity of the final wash water at a ' is the washing water temperature T w is the conductivity of the initial deionized water at , and C is the temperature coefficient.

4. The method for calculating the equivalent salt density of insulator salt spray according to claim 3 is characterized in that: In step S3, the formula The calculated salt spray is the corrected salt spray equivalent salt density ESDD4 of the pre-configured salt spray solution, where γ′ is the washing water temperature T w The conductivity of the pre-prepared salt spray solution at .

5. The method for calculating the equivalent salt density of insulator salt spray according to claim 3 is characterized in that: C＝0.02。 6. The method for calculating the equivalent salt density of insulator salt spray according to claim 3, characterized in that: In step S4, the formula The equivalent salt density ESDD5 of salt spray after nonlinear correction is calculated.

7. The method for calculating the equivalent salt density of insulator salt spray according to claim 4, characterized in that: In step S4, the formula The calculated salt spray is the equivalent salt density ESDD6 of the pre-configured salt spray solution after nonlinear correction.

8. An insulator salt spray equivalent salt density calculation device, characterized in that: include: at least one processor, and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to: By formula Calculate the equivalent salt density ESDD1 of the salt spray on the insulator surface, where γ is the measured conductivity of the washing water, V is the volume of the washing water, S is the surface area of ​​the insulator, and γ eq The equivalent conductivity of 1g of NaCl dissolved in 1L of water at 20℃; Calculate the equivalent salt density ESDD2 of the insulator surface salt spray that reduces the offset error according to the formula of the equivalent salt density ESDD1 of the insulator surface salt spray; Calculate the corrected equivalent salt density of salt spray ESDD3 and the corrected equivalent salt density of salt spray ESDD4 when the salt spray is a pre-configured salt spray solution; Calculate the equivalent salt density ESDD5 of the salt spray after nonlinear correction and the equivalent salt density ESDD6 of the salt spray after nonlinear correction when the salt spray is a pre-configured salt spray solution.

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