Epoxy resin performance evaluation method based on energy factors

Abstract

The invention provides an epoxy resin performance evaluation method based on an energy factor, which is characterized in that an epoxy resin reliability test platform based on a breakdown energy factor is established, and the evaluation steps are as follows: placing a sample made of epoxy resin in an experimental device memory; adjusting the output voltage of the electric energy excitation control terminal through the upper computer, continuously increasing the applied voltage until the voltage detector detects that the voltage at the two ends of the epoxy resin sample is zero, feeding back the current of the circuit and the voltage values at the two ends of the epoxy resin sample during breakdown, and calculating to obtain the theoretical value of the energy used by the epoxy resin sample. The method comprises the following steps: modeling an energy factor value formula by adopting a particle swarm optimization algorithm, calculating an error coefficient which minimizes an error, calculating to obtain an optimized energy factor value, calculating to obtain a reliability evaluation factor of the epoxy resin through the energy factor, and evaluating the reliability of the epoxy resin. The invention aims to provide an epoxy resin performance evaluation method based on an energy factor, and reference is provided for safe and stable operation of a power system.

Description

Technical Field

[0001] The invention relates to the field of epoxy resin insulation performance evaluation, in particular to an epoxy resin performance evaluation method based on energy factors. Background Art

[0002] Insulating resin is widely used in the field of electrical insulation due to its excellent electrical insulation performance, mechanical properties, corrosion resistance and mature technology. For example, bushings, contact boxes, post insulators, and insulating sleeves can effectively isolate electrical components from the complex external environment as a packaging material, thereby improving the insulation performance of the equipment. However, with the continuous increase in the capacity of the power system, epoxy resin faces the phenomenon of declining insulation health in a long-term high-voltage environment, and its own decline in insulation performance restricts the reliability and service life of the equipment. Once the insulation performance of epoxy resin is lower than a certain threshold, it is easy to cause electrical breakdown and scarring and ablation, and cause electrical equipment and components to fail and damage. The decline in the insulation performance of epoxy resin causes a very high failure rate of power equipment, and the insulation performance of epoxy resin affects the safe and stable operation of the power system.

[0003] At present, there is a lack of an energy factor-based epoxy resin performance evaluation method to determine the insulation reliability of epoxy resin under high voltage conditions. The present invention is an energy factor-based epoxy resin reliability test platform, which considers the energy factor parameters of epoxy resin, calculates the insulation performance evaluation factor of epoxy resin, and provides a certain reference for the performance evaluation of epoxy resin. Summary of the invention

[0004] In order to accurately evaluate the insulating performance state of epoxy resin, the present invention provides an epoxy resin performance evaluation method based on energy factor.

[0005] The technical solution for achieving the purpose of the present invention is as follows, comprising the following steps:

[0006] Step 1: First, an energy factor-based epoxy resin reliability test platform is built, which includes: a host computer (1), an electric energy excitation control terminal (2), a protective impedance (3), a voltage detector (4), an anode ball (5), an epoxy resin sample (6), a cathode ball (7), a test container (8), transformer oil (9), a current detector (10), a current detector data terminal (11), a voltage detector data terminal (12), and a grounding device (13);

[0007] The host computer (1) is connected to the electric energy excitation control terminal (2), the protective impedance (3), the anode ball (5), the epoxy resin sample (6), the cathode ball (7), the current detector (10), and the grounding device (13) to form an experimental main circuit;

[0008] The transformer oil (9) fills the interior of the test container (8), and the anode ball (5), the epoxy resin sample (6) and the cathode ball (7) are placed in the interior of the test container (8), and the epoxy resin sample (6) is a round piece with a diameter of 80 mm and a thickness of 1 mm;

[0009] The host computer (1) is connected to the voltage detector data terminal (12) and the voltage detector (4), and the voltage detector (4) is connected in parallel to the test container (8);

[0010] The host computer (1) is connected to the current detector data terminal (11) and the current detector (10);

[0011] A method for evaluating epoxy resin performance based on energy factor is characterized by comprising the following steps:

[0012] S1: The upper computer (1) sends a power supply instruction to the electric energy excitation control terminal (2), and the electric energy excitation control terminal (2) sends an initial voltage and outputs a voltage after passing through the protective impedance (3). The voltage makes the anode ball (5) add a high potential, and the cathode ball (7) forms a low potential due to being connected to the grounding device (13). At this time, a voltage difference is formed between the upper and lower surfaces of the epoxy resin sample (6);

[0013] S2: sending a program instruction to increase the voltage at a rate of 2 kV / s to the electric energy excitation control terminal (2) through the host computer (1), continuously increasing the voltage applied to the anode ball (5), and the voltage detector (4) detecting the voltage difference of the epoxy resin sample (6);

[0014] S3: When the voltage difference detected by the voltage detector (4) of the epoxy resin sample (6) is zero, it means that the epoxy resin sample (6) has been broken down, and the voltage detector data terminal (12) returns the breakdown voltage U m To the host computer (1), the current detector (10) will calculate the breakdown current I j The current is transmitted to the host computer (1) through the current detector data terminal (11), and the host computer (1) records the breakdown time T from the start of voltage application to the breakdown. j ;

[0015] S4: Taking into account multiple tests, multiple groups of breakdown voltage U m , breakdown current I j and breakdown time T j The breakdown energy E of the epoxy resin sample (6) is calculated as j Theoretical calculated value:

[0016]

[0017] In formula (1), E j is the energy factor value of epoxy resin sample, Um is the breakdown voltage, I j is the breakdown current, T j is the breakdown time from the start of voltage application to breakdown, λ is the error coefficient, and x is the integral variable;

[0018] S5: Use the particle swarm optimization algorithm to model the energy factor value formula and calculate the λ0 value that minimizes the error. The specific steps are as follows:

[0019] 1) Generate an initial population with uniformly distributed particles and velocities, and set stopping conditions;

[0020] 2) Calculate the optimal position of the group according to formula (2):

[0021]

[0022] In the formula, f(x) represents the objective function, n is the number of actual test data sets, and E ji is the energy factor standard value calculated corresponding to the i-th breakdown voltage value, E Ri is the actual value of the energy factor measured corresponding to the i-th breakdown voltage value;

[0023] 3) Update the position and velocity of each particle;

[0024] 4) Calculate the objective function value of each particle position, and update the optimal position of the entire group and the individual historical optimal position of each particle at the same time;

[0025] 5) If the stop condition is met, stop searching and output the search results; otherwise, return to step 3);

[0026] S6: Substitute the λ0 obtained in S5 into formula (1) to obtain the optimized calculation formula:

[0027]

[0028] In formula (3), E j0 is the energy factor value after parameter optimization, λ0 is the optimal error coefficient obtained by optimization;

[0029] S7: Consider the optimized energy factor value E j0 , calculate the epoxy resin reliability evaluation factor α:

[0030]

[0031] In formula (4), E j0 is the energy factor value after parameter optimization;

[0032] Based on the epoxy resin reliability evaluation factor α obtained in the above steps, an evaluation is performed. When α∈(0, 1], the epoxy resin is considered to have good reliability; when α∈(1, +∞], it indicates that the epoxy resin has poor reliability and cannot be used in high-voltage power equipment to ensure insulation safety.

[0033] The beneficial effects of the present invention are:

[0034] 1) A test platform for the insulation performance of epoxy resin under extreme high voltage conditions was built, which can effectively simulate the extreme insulation state of epoxy resin under extreme high voltage environments;

[0035] 2) Based on the test platform, the reliability evaluation factor of epoxy resin under extreme conditions can be accurately obtained, and suggestions are made through the reliability evaluation factor of epoxy resin under high-voltage extreme conditions to further improve the insulation stability of the power system;

[0036] 3) The present invention is mainly completed through a host computer, and is easy to operate and safe and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of an epoxy resin performance evaluation test platform based on energy factors shown in this application; DETAILED DESCRIPTION

[0038] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings. A specific implementation of an epoxy resin performance evaluation method based on energy factor includes the following steps:

[0039] Step 1: First, an energy factor-based epoxy resin reliability test platform is built, which includes: a host computer (1), an electric energy excitation control terminal (2), a protective impedance (3), a voltage detector (4), an anode ball (5), an epoxy resin sample (6), a cathode ball (7), a test container (8), transformer oil (9), a current detector (10), a current detector data terminal (11), a voltage detector data terminal (12), and a grounding device (13);

[0040] The host computer (1) is connected to the electric energy excitation control terminal (2), the protective impedance (3), the anode ball (5), the epoxy resin sample (6), the cathode ball (7), the current detector (10), and the grounding device (13) to form an experimental main circuit;

[0041] The transformer oil (9) fills the interior of the test container (8), and the anode ball (5), the epoxy resin sample (6) and the cathode ball (7) are placed in the interior of the test container (8), and the epoxy resin sample (6) is a round piece with a diameter of 80 mm and a thickness of 1 mm;

[0042] The host computer (1) is connected to the voltage detector data terminal (12) and the voltage detector (4), and the voltage detector (4) is connected in parallel to the test container (8);

[0043] The host computer (1) is connected to the current detector data terminal (11) and the current detector (10);

[0044] A method for evaluating epoxy resin performance based on energy factor is characterized by comprising the following steps:

[0045] S1: The upper computer (1) sends a power supply instruction to the electric energy excitation control terminal (2), and the electric energy excitation control terminal (2) sends an initial voltage and outputs a voltage after passing through the protective impedance (3). The voltage makes the anode ball (5) add a high potential, and the cathode ball (7) forms a low potential due to being connected to the grounding device (13). At this time, a voltage difference is formed between the upper and lower surfaces of the epoxy resin sample (6);

[0046] S2: sending a program instruction to increase the voltage at a rate of 2 kV / s to the electric energy excitation control terminal (2) through the host computer (1), continuously increasing the voltage applied to the anode ball (5), and the voltage detector (4) detecting the voltage difference of the epoxy resin sample (6);

[0047] S3: When the voltage difference detected by the voltage detector (4) of the epoxy resin sample (6) is zero, it means that the epoxy resin sample (6) has been broken down, and the voltage detector data terminal (12) returns the breakdown voltage U m To the host computer (1), the current detector (10) will calculate the breakdown current I j The current is transmitted to the host computer (1) through the current detector data terminal (11), and the host computer (1) records the breakdown time T from the start of voltage application to the breakdown. j ;

[0048] S4: Taking into account multiple tests, multiple groups of breakdown voltage U m , breakdown current I j and breakdown time T j The breakdown energy E of the epoxy resin sample (6) is calculated as j Theoretical calculated value:

[0049]

[0050] In formula (1), E j is the energy factor value of epoxy resin sample, U m is the breakdown voltage, I j is the breakdown current, T j is the breakdown time from the start of voltage application to breakdown, λ is the error coefficient, and x is the integral variable;

[0051] S5: Use the particle swarm optimization algorithm to model the energy factor value formula and calculate the λ0 value that minimizes the error. The specific steps are as follows:

[0052] 3) Generate an initial population with uniformly distributed particles and velocities, and set stopping conditions;

[0053] 4) Calculate the optimal position of the group according to formula (2):

[0054]

[0055] In the formula, f(x) represents the objective function, n is the number of actual test data sets, and E ji is the energy factor standard value calculated corresponding to the i-th breakdown voltage value, E Ri is the actual value of the energy factor measured corresponding to the i-th breakdown voltage value;

[0056] 3) Update the position and velocity of each particle;

[0057] 4) Calculate the objective function value of each particle position, and update the optimal position of the entire group and the individual historical optimal position of each particle at the same time;

[0058] 6) If the stop condition is met, stop searching and output the search results; otherwise, return to step 3);

[0059] S6: Substitute the λ0 obtained in S5 into formula (1) to obtain the optimized calculation formula:

[0060]

[0061] In formula (3), E j0 is the energy factor value after parameter optimization, λ0 is the optimal error coefficient obtained by optimization;

[0062] S7: Consider the optimized energy factor value E j0 , calculate the epoxy resin reliability evaluation factor α:

[0063]

[0064] In formula (4), E j0 is the energy factor value after parameter optimization;

[0065] Based on the epoxy resin reliability evaluation factor α obtained in the above steps, an evaluation is performed. When α∈(0, 1], the epoxy resin is considered to have good reliability; when α∈(1, +∞], it indicates that the epoxy resin has poor reliability and cannot be used in high-voltage power equipment to ensure insulation safety.

Claims

1. A method for evaluating epoxy resin performance based on energy factor, characterized in that: Firstly, an epoxy resin reliability test platform based on energy factor is built, which includes: a host computer (1), an electric energy excitation control terminal (2), a protective impedance (3), a voltage detector (4), an anode ball (5), an epoxy resin sample (6), a cathode ball (7), a test container (8), transformer oil (9), a current detector (10), a current detector data terminal (11), a voltage detector data terminal (12), and a grounding device (13); The host computer (1) is connected to the electric energy excitation control terminal (2), the protective impedance (3), the anode ball (5), the epoxy resin sample (6), the cathode ball (7), the current detector (10), and the grounding device (13) to form an experimental main circuit; The transformer oil (9) fills the interior of the test container (8), and the anode ball (5), the epoxy resin sample (6) and the cathode ball (7) are placed in the interior of the test container (8), and the epoxy resin sample (6) is a round piece with a diameter of 80 mm and a thickness of 1 mm; The host computer (1) is connected to the voltage detector data terminal (12) and the voltage detector (4), and the voltage detector (4) is connected in parallel to the test container (8); The host computer (1) is connected to the current detector data terminal (11) and the current detector (10); A method for evaluating epoxy resin performance based on energy factor is characterized in that: The following steps are involved: S1: The upper computer (1) sends a power supply instruction to the electric energy excitation control terminal (2), and the electric energy excitation control terminal (2) sends an initial voltage and outputs a voltage after passing through the protective impedance (3). The voltage makes the anode ball (5) add a high potential, and the cathode ball (7) forms a low potential due to being connected to the grounding device (13). At this time, a voltage difference is formed between the upper and lower surfaces of the epoxy resin sample (6); S2: sending a program instruction to increase the voltage at a rate of 2 kV / s to the electric energy excitation control terminal (2) through the host computer (1), continuously increasing the voltage applied to the anode ball (5), and the voltage detector (4) detecting the voltage difference of the epoxy resin sample (6); S3: When the voltage difference detected by the voltage detector (4) of the epoxy resin sample (6) is zero, it means that the epoxy resin sample (6) has been broken down, and the voltage detector data terminal (12) returns the breakdown voltage U m To the host computer (1), the current detector (10) will calculate the breakdown current I j The current is transmitted to the host computer (1) through the current detector data terminal (11), and the host computer (1) records the breakdown time T from the start of voltage application to the breakdown. j ; S4: Taking into account multiple tests, multiple groups of breakdown voltage U m , breakdown current I j and breakdown time T j The energy factor E used for the epoxy resin sample (6) is calculated as j Theoretical calculated value: In formula (1), E j is the energy factor value of epoxy resin sample, U m is the breakdown voltage, I j is the breakdown current, T j is the breakdown time from the start of voltage application to breakdown, λ is the error coefficient, and x is the integral variable; S5: Use the particle swarm optimization algorithm to model the energy factor value formula and calculate the λ0 value that minimizes the error. The specific steps are as follows: 1) Generate an initial population with uniformly distributed particles and velocities, and set stopping conditions; 2) Calculate the optimal position of the group according to formula (2): In the formula, f(x) represents the objective function, n is the number of actual test data sets, and E ji is the energy factor standard value calculated corresponding to the i-th breakdown voltage value, E Ri is the actual value of the energy factor measured corresponding to the i-th breakdown voltage value; 3) Update the position and velocity of each particle; 4) Calculate the objective function value of each particle position, and update the optimal position of the entire group and the individual historical optimal position of each particle at the same time; 5) If the stop condition is met, stop searching and output the search results; otherwise, return to step 3); S6: Substitute the λ0 obtained in S5 into formula (1) to obtain the optimized calculation formula: In formula (3), E j0 is the energy factor value after parameter optimization, λ0 is the optimal error coefficient obtained by optimization; S7: Consider the optimized energy factor value E j0 , calculate the epoxy resin reliability evaluation factor α: In formula (4), E j0 is the energy factor value after parameter optimization; Based on the epoxy resin reliability evaluation factor α obtained in the above steps, an evaluation is performed. When α∈(0, 1], the epoxy resin is considered to have good reliability; when α∈(1, +∞], it indicates that the epoxy resin has poor reliability and cannot be used in high-voltage power equipment to ensure insulation safety.

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