An alternating electric field assisted composite material preparation regulation method, device and medium

Abstract

The embodiment of the specification discloses an alternating current field assisted composite material preparation control method, equipment and medium, relates to the material preparation technical field, and the method comprises the following steps: obtaining the filler orientation equivalent circuit corresponding to the filler orientation in the filler orientation process under the excitation of an applied alternating current power supply, so as to determine the actual input energy of the applied alternating current power supply in the filler orientation process by means of the power supply parameters of the applied alternating current power supply and the filler orientation equivalent circuit obtained in advance, obtain the particle motion parameters in the filler orientation process by means of a numerical model and the parameters of the applied alternating current power supply, and determine the filler orientation required energy according to the particle motion parameters in the filler orientation process; based on the actual input energy of the applied alternating current power supply in the filler orientation process and the filler orientation required energy, an orientation degree evaluation index is generated; and according to the orientation degree evaluation index, the power excitation parameters of the applied alternating current power supply are determined, so as to control the preparation process of the composite material by changing the power excitation parameters.

Description

Technical Field

[0001] This specification relates to the field of materials preparation technology, and in particular to a method, equipment and medium for controlling the preparation of composite materials assisted by an alternating electric field. Background Technology

[0002] In recent years, high-voltage, high-power silicon carbide (SiC) devices have become the foundation for the development of new power grid technologies. Wide-bandgap silicon carbide power modules are gradually evolving towards higher voltage, higher current, and miniaturization. Silicon elastomers (SEs), due to their high dissociation energy and low energy barrier of siloxane bond rotation, can operate continuously at 250°C and are widely used as encapsulation insulation for power modules. However, the dielectric parameter mismatch at the junction of the silicon elastomer, AlN ceramic substrate, and metal layer within the power module can cause local electric field distortion, leading to partial discharge, affecting insulation capacity, and ultimately causing power module failure. By doping silicon elastomers with conductive or semiconductor fillers, such as carbon nanotubes, carbon black, zinc oxide, and silicon carbide whiskers (SiCw), composite insulating materials with excellent nonlinear conductivity can be obtained.

[0003] Furthermore, the orientation of fillers in composite materials has a significant impact on their dielectric properties. Current technologies use scanning electron microscopy (SEM) and X-ray diffraction (XRD) to evaluate the properties of composite materials and adjust the preparation process. However, SEM and XRD can only characterize the local arrangement of filler particles in the composite material and cannot reflect the orientation of the overall electrical conductivity network. They also do not consider energy losses during large-scale preparation, resulting in control parameters that cannot meet the preparation requirements. Summary of the Invention

[0004] This specification provides one or more embodiments of a method, device, and medium for controlling the preparation of composite materials assisted by an alternating electric field, which addresses the following technical problem: SEM and XRD can only characterize the local arrangement of filler particles in composite materials, and cannot reflect the orientation of the overall electrical conductivity network. They also do not consider energy loss during large-scale preparation, resulting in control parameters that cannot meet the preparation requirements.

[0005] One or more embodiments of this specification employ the following technical solutions:

[0006] This specification provides one or more embodiments of an AC electric field-assisted composite material preparation control method. The method includes: acquiring an equivalent circuit for filler orientation during the composite material preparation process under the excitation of an external AC power source; determining the actual input energy of the external AC power source during the filler orientation process using pre-acquired power parameters of the external AC power source and the equivalent circuit for filler orientation, wherein the actual input energy is related to the voltage application time; acquiring a pre-constructed numerical model corresponding to the composite material; simulating the particle motion of the composite material using the numerical model and the external AC power source parameters to obtain particle motion parameters during the filler orientation process; wherein the numerical model includes rotational dynamics equations corresponding to the particle rotation process and... The attraction kinetic equation corresponding to the particle attraction process is defined. Based on the particle motion parameters during the filler orientation process, the filler orientation energy requirement of the particles under the AC electric field of the applied AC power supply is determined, wherein the filler orientation energy requirement includes the particle rotation energy requirement and the particle attraction energy requirement. Based on the actual input energy of the applied AC power supply and the filler orientation energy requirement during the filler orientation process, an orientation degree evaluation index is generated, wherein the orientation degree evaluation index is used to represent the fully oriented state of the composite material. Based on the orientation degree evaluation index, the power excitation parameters of the applied AC power supply are determined, so as to regulate the preparation process of the composite material by changing the power excitation parameters, wherein the power excitation parameters include the power amplitude, power frequency, and application time.

[0007] Furthermore, obtaining the filler orientation equivalent circuit corresponding to the filler orientation during the composite material preparation process under the excitation of an external AC power supply specifically includes: equating the added dielectric of the filler sample in the filler orientation process to a dielectric equivalent resistance and dielectric equivalent capacitance, and equating the filler sample to a filler equivalent resistance and filler equivalent capacitance; connecting the dielectric equivalent resistance and the dielectric equivalent capacitance in parallel to generate a dielectric equivalent circuit; connecting the filler equivalent resistance and the filler equivalent capacitance in parallel to form a filler equivalent circuit; and connecting the dielectric equivalent circuit and the filler equivalent circuit in parallel, and then connecting them in series with the external AC power supply to determine the filler orientation equivalent circuit.

[0008] Furthermore, by using the pre-acquired power parameters of the external AC power supply and the equivalent circuit of the packing orientation, the actual input energy of the external AC power supply during the packing orientation process is determined. Specifically, this includes: using the pre-acquired power application parameters of the external AC power supply and the equivalent circuit of the packing orientation, determining the circuit loss energy of the external AC power supply; and using the circuit loss energy and the applied energy of the external AC power supply, determining the actual input energy of the external AC power supply during the packing orientation process.

[0009] Further, by using the pre-acquired power application parameters of the external AC power supply and the equivalent circuit of the filler orientation, the circuit loss energy of the external AC power supply is determined. Specifically, this includes: acquiring the power application parameters of the external AC power supply, wherein the power application parameters include the effective value of the voltage, the effective value of the current, the phase angle, and the voltage application time; in the equivalent circuit of the filler orientation, the equivalent circuit of the filler is opened to perform an unloaded test on the filler sample, and the equivalent dielectric resistance value is calculated; based on the equivalent dielectric resistance, the power application parameters, and the pre-acquired system temperature of the composite material preparation system, the energy loss energy is determined according to the formula... Determine the circuit loss energy of the external AC power supply; wherein, W loss The circuit energy loss is represented by U, the effective voltage value, R1, the equivalent dielectric resistance, t1, and K. B is the Boltzmann constant, and T is the system temperature.

[0010] Further, based on the particle motion parameters during the packing orientation process, the packing orientation energy requirement of the particles under the AC electric field of the applied AC power supply is determined, specifically including: determining the electric field strength of the applied AC power supply; determining the particle rotation energy requirement based on the electric field strength and the particle motion parameters; determining the particle attraction energy requirement between particles based on the particle motion parameters during the packing orientation process; and determining the packing orientation energy requirement through the particle rotation energy requirement and the particle attraction energy requirement, wherein the packing orientation energy requirement is the energy requirement corresponding to the fully oriented state.

[0011] Furthermore, based on the actual input energy of the external AC power supply and the energy required for the packing orientation process, an orientation degree evaluation index is generated, specifically including: based on the actual input energy of the external AC power supply and the energy required for the packing orientation process, according to the formula... Generate orientation assessment indicators, where S k ΔW is the orientation evaluation index. s The energy required for the orientation of the filler, ΔW h The actual input energy is T, and the system temperature of the composite material preparation system is T.

[0012] Further, based on the orientation evaluation index, the power excitation parameters of the applied AC power supply are determined, specifically including: fixing multiple other power excitation parameter values ​​besides the voltage application time in the power excitation parameters; adjusting the voltage application time to determine the orientation evaluation index corresponding to each voltage application time; when there is a specified orientation evaluation index with a specified value, using the specified voltage application time corresponding to the specified orientation evaluation index and the multiple other power excitation parameter values ​​as the power excitation parameters of the applied AC power supply.

[0013] Further, based on the actual input energy of the external AC power supply and the energy required for filler orientation during the filler orientation process, an orientation degree evaluation index is generated. The method then further includes: monitoring the composite material preparation process to determine the real-time orientation degree evaluation index; when the real-time orientation degree evaluation index is less than a specified value, determining the current state corresponding to the real-time orientation degree evaluation index of the composite material preparation process as an incompletely oriented state; when the real-time orientation degree evaluation index is equal to the specified value, determining the current state corresponding to the real-time orientation degree evaluation index of the composite material preparation process as a fully oriented state; and when the real-time orientation degree evaluation index is greater than the specified value, determining the current state of the composite material preparation process as an over-fully oriented state.

[0014] This specification provides one or more embodiments of an AC electric field-assisted composite material preparation control device, comprising:

[0015] At least one processor; and,

[0016] A memory communicatively connected to the at least one processor; wherein,

[0017] The memory stores instructions that can be executed by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to:

[0018] Obtain the equivalent circuit of filler orientation during the composite material preparation process under the excitation of an external AC power source. Based on the pre-obtained power parameters of the external AC power source and the equivalent circuit of the filler orientation, determine the actual input energy of the external AC power source during the filler orientation process, wherein the actual input energy is related to the voltage application time. Obtain a pre-constructed numerical model corresponding to the composite material. Simulate the particle motion of the composite material using the numerical model and the external AC power source parameters to obtain the particle motion parameters during the filler orientation process. The numerical model includes the rotational dynamics equations corresponding to the particle rotation process and the attraction dynamics equations corresponding to the particle attraction process. Based on the... The particle motion parameters during the filler orientation process are used to determine the energy required for filler orientation under the AC electric field of the applied AC power supply. This energy requirement includes the energy required for particle rotation and the energy required for particle attraction. Based on the actual input energy of the applied AC power supply and the energy required for filler orientation during the filler orientation process, an orientation degree evaluation index is generated. This index represents the fully oriented state of the composite material. According to the orientation degree evaluation index, the power excitation parameters of the applied AC power supply are determined to regulate the preparation process of the composite material by changing these parameters. These parameters include power amplitude, power frequency, and application time.

[0019] This specification provides one or more embodiments of a non-volatile computer storage medium storing computer-executable instructions, wherein the computer-executable instructions are configured as follows:

[0020] Obtain the equivalent circuit of filler orientation during the composite material preparation process under the excitation of an external AC power source. Based on the pre-obtained power parameters of the external AC power source and the equivalent circuit of the filler orientation, determine the actual input energy of the external AC power source during the filler orientation process, wherein the actual input energy is related to the voltage application time. Obtain a pre-constructed numerical model corresponding to the composite material. Simulate the particle motion of the composite material using the numerical model and the external AC power source parameters to obtain the particle motion parameters during the filler orientation process. The numerical model includes the rotational dynamics equations corresponding to the particle rotation process and the attraction dynamics equations corresponding to the particle attraction process. Based on the... The particle motion parameters during the filler orientation process are used to determine the energy required for filler orientation under the AC electric field of the applied AC power supply. This energy requirement includes the energy required for particle rotation and the energy required for particle attraction. Based on the actual input energy of the applied AC power supply and the energy required for filler orientation during the filler orientation process, an orientation degree evaluation index is generated. This index represents the fully oriented state of the composite material. According to the orientation degree evaluation index, the power excitation parameters of the applied AC power supply are determined to regulate the preparation process of the composite material by changing these parameters. These parameters include power amplitude, power frequency, and application time.

[0021] The above-mentioned at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects: Through the above technical solution, from the perspective of energy conservation, a global evaluation index for filler orientation is proposed, which reflects the complete orientation state of the filler in the overall electrical conductivity network. Combined with the influence of power excitation parameters on the orientation evaluation index, the minimum energy consumption excitation parameters that can achieve complete orientation are determined while considering energy loss. This enables the control of the composite material preparation process. Considering the energy loss during large-scale preparation, the generated control parameters can meet the preparation requirements. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0023] Figure 1A schematic flowchart of an AC electric field-assisted composite material preparation and control method provided in the embodiments of this specification;

[0024] Figure 2 A schematic diagram of the circuit structure of an equivalent circuit for filler orientation provided in the embodiments of this specification;

[0025] Figure 3 A normalized curve diagram of current change during particle orientation provided in an embodiment of this specification;

[0026] Figure 4 This is a schematic diagram illustrating the variation trend of the actual input energy of an external AC power supply under different electric fields over time, provided as an embodiment of this specification.

[0027] Figure 5 This specification provides an example of a composite material preparation system that illustrates the relationship between orientation evaluation index and applied voltage time.

[0028] Figure 6 This is a schematic diagram of an AC electric field-assisted composite material preparation and control device provided as an embodiment of this specification. Detailed Implementation

[0029] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments of this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this specification.

[0030] In recent years, high-voltage, high-power silicon carbide (SiC) devices have become the foundation for the development of new power grid technologies. Wide-bandgap silicon carbide power modules are gradually evolving towards higher voltage, higher current, and miniaturization. Silicon elastomers (SEs), due to their high dissociation energy and low energy barrier of siloxane bond rotation, can operate continuously at 250°C and are widely used as encapsulation insulation for power modules. However, the dielectric parameter mismatch at the junction of the silicon elastomer, AlN ceramic substrate, and metal layer within the power module can cause local electric field distortion, leading to partial discharge, affecting insulation capacity, and ultimately causing power module failure. By doping silicon elastomers with conductive or semiconductor fillers, such as carbon nanotubes, carbon black, zinc oxide, and silicon carbide whiskers (SiCw), composite insulating materials with excellent nonlinear conductivity can be obtained. Research shows that inducing high aspect ratio filler orientation through magnetic fields, electrospinning, shear current, and alternating electric fields is a feasible solution. Compared to the previous three methods, the AC electric field-assisted induced filler orientation method has the advantage of significantly reducing the filler concentration ratio and being able to precisely control the dielectric parameters of the composite material. In addition, experimental variables such as voltage amplitude and application time are easy to adjust.

[0031] Furthermore, the orientation of fillers in composite materials has a significant impact on their dielectric properties. Current technologies use SEM and XRD to evaluate the properties of composite materials and adjust the preparation process. However, SEM and XRD can only characterize the local arrangement of filler particles in the composite material and cannot reflect the orientation of the overall electrical conductivity network. They also do not consider energy losses during large-scale preparation, resulting in control parameters that cannot meet the preparation requirements.

[0032] This specification provides an AC electric field-assisted method for controlling the preparation of composite materials. It should be noted that the execution subject in this specification can be a server or any device with data processing capabilities. Figure 1 This is a schematic flowchart illustrating an AC electric field-assisted method for controlling the preparation of composite materials, as provided in the embodiments of this specification. Figure 1 As shown, the main steps include the following:

[0033] Step S101: Obtain the filler orientation equivalent circuit corresponding to the filler orientation during the composite material preparation process under the excitation of an external AC power source, so as to determine the actual input energy of the external AC power source during the filler orientation process by using the power parameters of the external AC power source obtained in advance and the filler orientation equivalent circuit.

[0034] The actual input energy is related to the voltage application time.

[0035] It should be noted that silicone elastomer (SE) can be selected as the insulating matrix, and silicon carbide whiskers (SiCw) with excellent nonlinear conductivity and an aspect ratio of approximately 100 can be used as the filler. To prevent filler agglomeration, γ-aminopropyltriethoxysilane (KH550) was used to modify the surface of SiCw. Based on this, the composite material was prepared by ultrasonic dispersion + planetary centrifugal mixing. First, 5% by mass of SiCw was added to the PDMS matrix and ultrasonically dispersed to obtain a filler dispersion. Using a planetary centrifugal mixer, the SiCw, PDMS, curing agent, and other components were mixed to obtain an insulating prepolymer. The prepolymer was coated between electrodes consisting of two parallel metal plates with a diameter of 8 cm and an insulating silicone rubber ring with a thickness of 0.4 mm. At room temperature of 25°C, AC voltages of different amplitudes and frequencies of 1 kHz were applied to both ends of the electrodes using a voltage amplifier. The UI signal during the voltage application process was accurately monitored using a current amplifier and a data acquisition card.

[0036] The orientation degree of fillers in composite materials has a significant impact on their dielectric properties. SEM and XRD can only characterize the local particle arrangement of fillers in composite materials and cannot reflect the overall orientation degree of the electrical conductivity network, thus the evaluation accuracy needs improvement. To address this issue, we construct a global orientation degree evaluation index for fillers based on an entropy model from the perspective of energy conservation. Entropy is essentially the "intrinsic disorder" of a system. Under an applied electric field, the orientation and self-assembly of SiCw in insulating prepolymers is an irreversible thermodynamic entropy decrease process. Therefore, we use the Clausius form of the second law of thermodynamics to calculate the entropy change of the isothermal system: In the formula, ΔS represents the entropy change, dQ represents the heat absorbed by the object, and ΔW represents the total energy. For the system under study, from a macroscopic perspective, ΔW corresponds to the energy W provided by the external power source. power With dissipated energy W loss The difference is denoted as ΔW. h From a microscopic perspective, ΔW includes the total energy required for particle rotation and the energy required for particle attraction, and is hereinafter denoted as ΔW. s .

[0037] Obtaining the filler orientation equivalent circuit corresponding to the filler orientation during the composite material preparation process under the excitation of an external AC power supply specifically includes: equating the filler sample in the filler orientation process with an added dielectric equivalent resistance and equivalent capacitance, and equating the filler sample with a filler equivalent resistance and equivalent capacitance; connecting the dielectric equivalent resistance and equivalent capacitance in parallel to generate a dielectric equivalent circuit; connecting the filler equivalent resistance and equivalent capacitance in parallel to form a filler equivalent circuit; and connecting the dielectric equivalent circuit and the filler equivalent circuit in parallel, and then connecting them in series with the external AC power supply to determine the filler orientation equivalent circuit.

[0038] In one embodiment of this specification, Figure 2 This is a schematic diagram of the equivalent circuit structure for a filler orientation process provided in an embodiment of this specification. Under the influence of an applied electric field, the equivalent circuit during the filler orientation process includes R1, which is the equivalent resistance of air or other dielectric (i.e., dielectric equivalent resistance), and C1, which is the equivalent capacitance of air or other dielectric (i.e., dielectric equivalent capacitance). The dielectric equivalent resistance and dielectric equivalent capacitance are connected in parallel to form the dielectric equivalent circuit. R2 represents the equivalent resistance of the filler sample (i.e., filler equivalent resistance), and C2 represents the equivalent capacitance of the filler sample (i.e., filler equivalent capacitance). The filler equivalent resistance and filler equivalent capacitance are connected in parallel to form the filler equivalent circuit. After connecting the dielectric equivalent circuit and the filler equivalent circuit in parallel, they are connected in series with an applied AC power supply to determine the filler orientation equivalent circuit.

[0039] By using the pre-acquired power parameters of the external AC power supply and the equivalent circuit of the filler orientation, the actual input energy of the external AC power supply during the filler orientation process is determined. Specifically, this includes: using the pre-acquired power application parameters of the external AC power supply and the equivalent circuit of the filler orientation, determining the circuit loss energy of the external AC power supply; and using the circuit loss energy and the applied energy of the external AC power supply, determining the actual input energy of the external AC power supply during the filler orientation process.

[0040] The circuit loss energy of the applied AC power supply is determined by using the pre-acquired power application parameters and the equivalent circuit of the filler orientation. Specifically, this includes: acquiring the power application parameters of the applied AC power supply, which include the effective voltage value, effective current value, phase angle, and voltage application time; in the equivalent circuit of the filler orientation, the equivalent circuit of the filler is opened to perform an unloaded test on the filler sample, and the equivalent dielectric resistance value is calculated; based on the equivalent dielectric resistance, the power application parameters, and the pre-acquired system temperature of the composite material preparation system, the energy loss energy is determined according to the formula... Determine the circuit loss energy of the external AC power supply; where W loss This circuit loses energy. U R1 is the effective value of the voltage, t1 is the equivalent resistance of the dielectric, and K is the voltage application time. B Let be the Boltzmann constant, and T be the system temperature.

[0041] In one embodiment of this specification, the input energy W of the power supply power It can be represented as: In the formula, U and I are the effective values ​​of voltage and current, respectively. t1 is the phase angle, and t1 is the voltage application time. Since the current magnitude is closely related to the packing network structure, the current is time-dependent.

[0042] The circuit loss consists of two parts: circuit loss and the inherent loss caused by particle movement overcoming temperature. The expression is: In the formula, K B R is Boltzmann's constant, T is the system temperature, and R1 is the equivalent loss resistance.

[0043] To solve for R1, we first perform an open-circuit test on the sample without adding filler, i.e., we open-circuit the equivalent circuit of the filler sample to perform an open-circuit test. At this time, only R1 and C1 exist in the circuit. The calculated equivalent resistance cross-sectional area is: Where ρ0 is the resistivity, h is the thickness of the filler sample, and I0 is the no-load test current. The area of ​​the filler sample is S2. According to Ohm's law, R1 can be expressed as:

[0044] ΔW h External input energy: ΔW h =W power -W loss That is, the input energy W of the power supply power With dissipated energy W loss difference.

[0045] Step S102: Obtain the numerical model corresponding to the pre-constructed composite material. Simulate the particle motion of the composite material using the numerical model and external AC power supply parameters to obtain the particle motion parameters during the filler orientation process.

[0046] The numerical model includes the rotational dynamics equations corresponding to the particle rotation process and the attraction dynamics equations corresponding to the particle attraction process.

[0047] In one embodiment of this specification, rod-shaped particles in the uncured composite material exhibit random distribution, rotation, and mutual attraction under an alternating electric field. Initially, the particles in the insulating matrix are uniformly dispersed due to Brownian motion. Upon application of an external electric field, the particles undergo electropolarization, resulting in the separation of internal positive and negative charges, which can be considered as dipoles. Based on the principle of minimum energy, under the influence of the electric field force, the viscous drag of the insulating matrix, and inertial forces, the particles rotate along the direction of the electric field. The specific dynamic equations are as follows: Where A1 is the inertial term, A2 is the damping term, and A3 is the electric field induced term.

[0048]

[0049] in, Where m is the particle mass; θ is the angle between the filler and the electric field direction, when the angle is 0, the major axis of the particle is parallel to the electric field direction; r and l are the minor and major semi-axis lengths of the rod-shaped particle, respectively; k = l / r is the aspect ratio; η is the matrix viscosity; r e P is the particle's equivalent radius; r P is the coefficient of rotational friction. t V is the coefficient of translational friction; V is the particle volume; E is the electric field strength; ε s and ε m ε and ν are the dielectric constants of the particle and the matrix, respectively; L is the principal axis polarization factor.

[0050] Simultaneously, due to the opposite charges at both ends of the polarized particles, they attract each other. The dynamic equation for this attraction process is as follows: Where, B2=6πηr e P t , Where x is the distance between particles, and x0 is the initial distance between particles. Ultimately, the particles form a chain-like structure arranged along the direction of the electric field under the influence of the alternating electric field.

[0051] Step S103: Based on the particle motion parameters during the packing orientation process, determine the energy required for the particles to orient in the packing under the AC electric field of the applied AC power supply.

[0052] The energy required for the orientation of the filler includes the energy required for particle rotation and the energy required for particle attraction.

[0053] Based on the particle motion parameters during the packing orientation process, the packing orientation energy required by the particles under the AC electric field of the applied AC power supply is determined. Specifically, this includes: determining the electric field strength of the applied AC power supply; determining the particle rotation energy required based on the electric field strength and the particle motion parameters; determining the particle attraction energy required based on the particle motion parameters during the packing orientation process; and determining the packing orientation energy required by the particle rotation energy and the particle attraction energy, wherein the packing orientation energy required is the energy required under the fully oriented state.

[0054] In one embodiment of this specification, at the microscopic level, it is necessary to calculate the energy required for a particle to rotate and migrate under an electric field. The particle is polarized in the electric field into an equivalent dipole moment with charges at both ends, and the torque it experiences is: Where E is the electric field strength, p eff The equivalent dipole moment can be expressed as: L=[ln(2p)-1] / p 2 .

[0055] Where V is the equivalent volume of the particle, w is the angular frequency, and ε *p ε is the complex permittivity of the filler. * m Let be the complex permittivity of the matrix, and L be the principal axis depolarization factor. Therefore, the final expression for the torque can be obtained as: Then it can be deduced that

[0056] Furthermore, the energy required for particles to attract each other comes from the work done by gravity, that is: but

[0057] Where l is the length of the major axis of the particle, and x0 is the initial distance between particles, the expression is:

[0058]

[0059] Therefore, the energy required for perfect orientation can be obtained as follows:

[0060]

[0061] Based on experimental data on the energy required for two-particle systems with three aspect ratios to align completely along the electric field direction under different field strengths and volume fractions, it can be found that the larger the aspect ratio of the filler, the smaller ΔWs and the lower the preparation energy consumption.

[0062] Furthermore, the two-particle system was extended to a multi-particle system. The total energy required for complete orientation of the entire insulating prepolymer system could be obtained. Experiments showed that, at the same volume fraction, ΔWs gradually increased with the increase of the applied electric field strength. This is because the increase in field strength enhances both the particle rotation torque and the interparticle interaction force. Similarly, ΔWs showed the same trend with the increase of filler content, which can be attributed to the increased number of particles in the mixture at higher volume fractions, resulting in an increase in the total energy required for complete rotation and attraction of all particles.

[0063] Step S104: Based on the actual input energy of the external AC power supply and the energy required for packing orientation during the packing orientation process, generate an orientation degree evaluation index.

[0064] The orientation evaluation index is used to represent the complete orientation state of the composite material.

[0065] Based on the actual input energy of the external AC power supply and the energy required for the orientation of the packing during the packing orientation process, an orientation degree evaluation index is generated. Specifically, this includes: based on the actual input energy of the external AC power supply and the energy required for the orientation of the packing during the packing orientation process, according to the formula... Generate orientation assessment indicators, where S k For this orientation assessment index, ΔW s The energy required for the orientation of this filler is ΔWh The actual input energy is T, and the system temperature of the composite material preparation system is T.

[0066] Based on this, in order to accurately assess the orientation degree of the electrical conductivity network, a method for calculating the shortest time required for complete orientation of the filler and an orientation degree evaluation index are proposed, under the condition that the external excitation voltage parameters are determined. ΔW h External input energy: ΔW h =W power -W loss .

[0067] When the input energy equals ΔW s When the time is shortest, the corresponding time t1 is the shortest time. Taking p = 100, φ (volume fraction of filler in matrix) = 5%, E = 600V / mm, and f = 1kHz as an example, the calculated ΔW s = -9.61J. When ΔW h =ΔW s At that time, the corresponding integration time is 896s. Figure 3 This specification provides a schematic diagram of a normalized curve of current change during particle orientation, as shown in the embodiments of this specification. Figure 3 The current curve shown in the figure reaches stability at around 912s, thus verifying the accuracy of the above model.

[0068] During the material preparation process, the relationship between the power input energy and time can be calculated in real time based on the current data. Figure 4 This diagram illustrates the variation of the actual input energy of an external AC power supply under different electric fields over time, as provided in the embodiments of this specification. After obtaining the particle motion parameters using a numerical model corresponding to the composite material, the filler orientation requirement energy ΔW is obtained through the above method. s According to the numerical model, the applied electric field and Figure 4 By comparing the corresponding curves, the shortest time required for the applied voltage to achieve complete orientation of the filler can be obtained, thereby reducing energy loss during the large-scale material preparation process.

[0069] Furthermore, based on the above model, orientation evaluation indicators are defined. Figure 5 This specification provides an example of a composite material preparation system that illustrates the relationship between orientation evaluation index and applied voltage time. Figure 5 The corresponding system conditions are as follows: p = 100, φ = 5%, E = 200V / mm ~ 1kV / mm, f = 1kHz isothermal insulating prepolymer system. The relationship between filler orientation degree and applied voltage time is as follows: Figure 5 As shown, in Figure 5 In the middle, use ΔS kThis represents the orientation evaluation index. The x-axis value corresponding to the intersection of the curve and the 0 baseline is the shortest time required for the filler to achieve complete orientation. When the entropy S... k The smaller the value, the higher the orientation degree of the filler.

[0070] Step S105: Based on the orientation evaluation index, determine the power excitation parameters of the applied AC power supply, so as to control the preparation process of the composite material by changing the power excitation parameters.

[0071] In one embodiment of this specification, the power excitation parameters of the external AC power supply required for complete orientation of the filler are determined based on the orientation degree evaluation index, so as to control the preparation process of the composite material by changing the power excitation parameters. These power excitation parameters include power amplitude, power frequency, and application time.

[0072] Based on the orientation evaluation index, the power excitation parameters of the external AC power supply are determined, specifically including: fixing multiple other power excitation parameter values ​​other than the voltage application time in the power excitation parameters; adjusting the voltage application time to determine the orientation evaluation index corresponding to each voltage application time; when there is a specified orientation evaluation index with a specified value, the specified voltage application time corresponding to the specified orientation evaluation index and the multiple other power excitation parameter values ​​are used as the power excitation parameters of the external AC power supply.

[0073] In one embodiment of this specification, other power excitation parameters can be fixed by controlling variable simulation, and an external AC excitation can be applied to the same composite material preparation system. The voltage application time corresponding to the orientation degree evaluation index being 0 is determined by the orientation degree evaluation index. This voltage application time is the shortest time corresponding to the complete orientation of the filler, which can effectively save energy consumption while ensuring the complete orientation of the filler.

[0074] Based on the actual input energy of the external AC power supply and the energy required for the filler orientation during the filler orientation process, an orientation degree evaluation index is generated. The method then further includes: monitoring the composite material preparation process to determine the real-time orientation degree evaluation index; when the real-time orientation degree evaluation index is less than a specified value, determining the current state corresponding to the real-time orientation degree evaluation index in the composite material preparation process as an incompletely oriented state; when the real-time orientation degree evaluation index is equal to the specified value, determining the current state corresponding to the real-time orientation degree evaluation index in the composite material preparation process as a fully oriented state; and when the real-time orientation degree evaluation index is greater than the specified value, determining the current state of the composite material preparation process as an over-fully oriented state.

[0075] In one embodiment of this specification, the current state of the filler can also be monitored using an orientation degree evaluation index. The power input energy is determined by the duration of the applied voltage, thus determining the real-time orientation degree evaluation index corresponding to the current application duration. When the real-time orientation degree evaluation index is less than 0, the current state corresponding to this index in the composite material preparation process is determined to be incompletely oriented, requiring continued voltage application. When the real-time orientation degree evaluation index equals 0, the current state corresponding to this index in the composite material preparation process is determined to be fully oriented, and this corresponds to the minimum energy consumption. When the real-time orientation degree evaluation index is greater than 0, the current state in the composite material preparation process is determined to be over-oriented, meaning it is in a fully oriented state, but was already fully oriented before the current moment, resulting in additional energy consumption.

[0076] Based on the above technical solution, a global evaluation index for filler orientation is proposed from the perspective of energy conservation, considering both the actual input energy of the external power source after loss at the macroscopic level and the energy required during particle rotation and mutual attraction at the microscopic level. This index reflects the fully oriented state of the filler in the overall electrical conductivity network. By combining the influence of power source excitation parameters on the orientation evaluation index and considering energy loss, the minimum energy consumption excitation parameters that can achieve full orientation are determined, thereby enabling the control of the composite material preparation process. Considering the energy loss during large-scale preparation, the generated control parameters can meet the preparation requirements.

[0077] This specification also provides an AC electric field-assisted composite material preparation control device, such as... Figure 6 As shown, the device includes: 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:

[0078] Obtain the equivalent circuit of filler orientation during the composite material preparation process under the excitation of an external AC power supply. Using the pre-obtained power supply parameters and the equivalent circuit, determine the actual input energy of the external AC power supply during the filler orientation process. This actual input energy is related to the voltage application time. Obtain a pre-constructed numerical model corresponding to the composite material. Using this numerical model and the external AC power supply parameters, simulate the particle motion of the composite material to obtain the particle motion parameters during the filler orientation process. The numerical model includes the rotational dynamics equations corresponding to the particle rotation process and the attraction dynamics equations corresponding to the particle attraction process. Based on... The particle motion parameters during the filler orientation process determine the energy required for filler orientation under the AC electric field of the applied AC power supply. This energy requirement includes the energy required for particle rotation and the energy required for particle attraction. Based on the actual input energy of the applied AC power supply and the energy required for filler orientation during the filler orientation process, an orientation degree evaluation index is generated. This index represents the fully oriented state of the composite material. According to the orientation degree evaluation index, the power excitation parameters of the applied AC power supply are determined. By changing these excitation parameters, the preparation process of the composite material can be controlled. These excitation parameters include power amplitude, power frequency, and application time.

[0079] This specification also provides a non-volatile computer storage medium storing computer-executable instructions, wherein the computer-executable instructions are configured as follows:

[0080] Obtain the equivalent circuit of filler orientation during the composite material preparation process under the excitation of an external AC power supply. Using the pre-obtained power supply parameters and the equivalent circuit, determine the actual input energy of the external AC power supply during the filler orientation process. This actual input energy is related to the voltage application time. Obtain a pre-constructed numerical model corresponding to the composite material. Using this numerical model and the external AC power supply parameters, simulate the particle motion of the composite material to obtain the particle motion parameters during the filler orientation process. The numerical model includes the rotational dynamics equations corresponding to the particle rotation process and the attraction dynamics equations corresponding to the particle attraction process. Based on... The particle motion parameters during the filler orientation process determine the energy required for filler orientation under the AC electric field of the applied AC power supply. This energy requirement includes the energy required for particle rotation and the energy required for particle attraction. Based on the actual input energy of the applied AC power supply and the energy required for filler orientation during the filler orientation process, an orientation degree evaluation index is generated. This index represents the fully oriented state of the composite material. According to the orientation degree evaluation index, the power excitation parameters of the applied AC power supply are determined. By changing these excitation parameters, the preparation process of the composite material can be controlled. These excitation parameters include power amplitude, power frequency, and application time.

[0081] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the embodiments of apparatus, devices, and non-volatile computer storage media are basically similar to the method embodiments, so the descriptions are relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0082] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0083] The devices, media, and methods provided in the embodiments of this specification are one-to-one correspondences. Therefore, the devices and media also have similar beneficial technical effects as their corresponding methods. Since the beneficial technical effects of the methods have been described in detail above, the beneficial technical effects of the devices and media will not be repeated here.

[0084] Those skilled in the art will understand that embodiments of this specification can be provided as methods, systems, or computer program products. Therefore, this specification may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this specification may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0085] This specification is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this specification. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0086] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0087] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0088] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0089] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0090] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0091] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0092] The above description is merely one or more embodiments of this specification and is not intended to limit this specification. Various modifications and variations can be made to the one or more embodiments of this specification by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of one or more embodiments of this specification should be included within the scope of the claims of this specification.

Claims

1. A method for controlling the preparation of composite materials assisted by an alternating electric field, characterized in that, The method includes: Obtain the filler orientation equivalent circuit corresponding to the filler orientation during the composite material preparation process under the excitation of an external AC power source, so as to determine the actual input energy of the external AC power source during the filler orientation process by using the power parameters of the external AC power source obtained in advance and the filler orientation equivalent circuit, wherein the actual input energy is related to the voltage application time; A pre-constructed numerical model corresponding to the composite material is obtained. The particle motion of the composite material is simulated using the numerical model and the external AC power supply parameters to obtain the particle motion parameters during the filler orientation process. The numerical model includes the rotational dynamics equation corresponding to the particle rotation process and the attraction dynamics equation corresponding to the particle attraction process. Based on the particle motion parameters during the packing orientation process, the packing orientation energy required by the particles under the AC electric field of the applied AC power supply is determined, wherein the packing orientation energy required includes the particle rotation energy and the particle attraction energy. Based on the actual input energy of the external AC power supply and the energy required for the filler orientation process, an orientation degree evaluation index is generated, wherein the orientation degree evaluation index is used to represent the fully oriented state of the composite material; Based on the orientation evaluation index, the power excitation parameters of the applied AC power supply are determined so as to regulate the preparation process of the composite material by changing the power excitation parameters. The power excitation parameters include power amplitude, power frequency and application time.

2. The method for controlling the preparation of composite materials assisted by an alternating electric field according to claim 1, characterized in that, Obtain the equivalent circuit of filler orientation during the composite material preparation process under the excitation of an external AC power supply, specifically including: The packing sample in the packing orientation process is added to a dielectric equivalent to a dielectric equivalent resistance and a dielectric equivalent capacitance, and the packing sample is equivalent to a packing equivalent resistance and a packing equivalent capacitance. The dielectric equivalent resistance and the dielectric equivalent capacitance are connected in parallel to generate a dielectric equivalent circuit. The equivalent resistance and equivalent capacitance of the packing are connected in parallel to form the equivalent circuit of the packing. The equivalent circuit of the medium and the equivalent circuit of the filler are connected in parallel and then connected in series with the external AC power supply to determine the equivalent circuit of the filler orientation.

3. The method for controlling the preparation of composite materials assisted by an alternating electric field according to claim 2, characterized in that, By using the pre-acquired power parameters of the external AC power supply and the equivalent circuit of the filler orientation, the actual input energy of the external AC power supply during the filler orientation process is determined, specifically including: The circuit loss energy of the external AC power supply is determined by using the pre-obtained power application parameters of the external AC power supply and the equivalent circuit of the filler orientation. The actual input energy of the external AC power supply during the filler orientation process is determined by the energy lost in the circuit and the energy applied by the external AC power supply.

4. The method for controlling the preparation of composite materials assisted by an alternating electric field according to claim 3, characterized in that, By using the pre-acquired power application parameters of the external AC power supply and the equivalent circuit of the filler orientation, the circuit loss energy of the external AC power supply is determined, specifically including: Obtain the power application parameters of the external AC power supply, wherein the power application parameters include the effective value of voltage, the effective value of current, the phase angle, and the voltage application time; In the packing orientation equivalent circuit, the packing equivalent circuit is opened to perform an unloaded test on the packing sample and calculate the dielectric equivalent resistance value of the dielectric equivalent resistance. Based on the equivalent resistance of the dielectric, the power supply parameters, and the pre-obtained system temperature of the composite material preparation system, according to the formula... Determine the circuit loss energy of the external AC power supply; in, The circuit loses energy. This is the effective value of the voltage. This is the equivalent resistance value of the dielectric. For the voltage application time, Boltzmann's constant, The system temperature is [temperature value].

5. The method for controlling the preparation of composite materials assisted by an alternating electric field according to claim 1, characterized in that, Based on the particle motion parameters during the packing orientation process, the energy required for packing orientation under the AC electric field of the applied AC power supply is determined, specifically including: Determine the electric field strength of the external AC power supply, and based on the electric field strength and the particle motion parameters, determine the energy required for the particle to rotate; Based on the particle motion parameters during the packing orientation process, determine the energy required for particle attraction between particles; The filler orientation energy is determined by the particle rotation energy requirement and the particle attraction energy requirement, wherein the filler orientation energy requirement is the energy requirement corresponding to the fully oriented state.

6. The method for controlling the preparation of composite materials assisted by an alternating electric field according to claim 1, characterized in that, Based on the actual input energy of the external AC power supply during the packing orientation process and the energy required for packing orientation, an orientation degree evaluation index is generated, specifically including: Based on the actual input energy of the external AC power supply during the packing orientation process and the energy required for packing orientation, according to the formula... Generate orientation assessment indicators, among which... The orientation evaluation index is... The energy required for the orientation of the filler The actual input energy, The system temperature of the composite material preparation system.

7. The method for controlling the preparation of composite materials assisted by an alternating electric field according to claim 1, characterized in that, Based on the orientation evaluation index, the power excitation parameters of the applied AC power supply are determined, specifically including: Several other power excitation parameter values, excluding the voltage application time, are fixed in the power excitation parameters; The voltage application time is adjusted to determine the orientation evaluation index corresponding to each voltage application time; When a specified orientation evaluation index has a specified value, the specified voltage application time corresponding to the specified orientation evaluation index and the values ​​of the plurality of other power excitation parameters are used as the power excitation parameters of the external AC power supply.

8. The method for controlling the preparation of composite materials assisted by an alternating electric field according to claim 1, characterized in that, Based on the actual input energy of the external AC power supply and the energy required for the packing orientation process, an orientation degree evaluation index is generated. The method then further includes: Monitor the composite material preparation process and determine real-time orientation evaluation indicators; When the real-time orientation degree evaluation index is less than a specified value, the current state corresponding to the real-time orientation degree evaluation index in the composite material preparation process is determined to be an incompletely oriented state. When the real-time orientation evaluation index is equal to the specified value, the current state corresponding to the real-time orientation evaluation index in the composite material preparation process is determined to be a fully oriented state. When the real-time orientation evaluation index is greater than the specified value, the current state of the composite material preparation process is determined to be an over-fully oriented state.

9. An AC electric field-assisted composite material preparation control device, characterized in that, The device includes: 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, which, when executed by the at least one processor, enable the at least one processor to: Obtain the filler orientation equivalent circuit corresponding to the filler orientation during the composite material preparation process under the excitation of an external AC power source, so as to determine the actual input energy of the external AC power source during the filler orientation process by using the power parameters of the external AC power source obtained in advance and the filler orientation equivalent circuit, wherein the actual input energy is related to the voltage application time; A pre-constructed numerical model corresponding to the composite material is obtained. The particle motion of the composite material is simulated using the numerical model and the external AC power supply parameters to obtain the particle motion parameters during the filler orientation process. The numerical model includes the rotational dynamics equation corresponding to the particle rotation process and the attraction dynamics equation corresponding to the particle attraction process. Based on the particle motion parameters during the packing orientation process, the packing orientation energy required by the particles under the AC electric field of the applied AC power supply is determined, wherein the packing orientation energy required includes the particle rotation energy and the particle attraction energy. Based on the actual input energy of the external AC power supply and the energy required for the filler orientation process, an orientation degree evaluation index is generated, wherein the orientation degree evaluation index is used to represent the fully oriented state of the composite material; Based on the orientation evaluation index, the power excitation parameters of the applied AC power supply are determined so as to regulate the preparation process of the composite material by changing the power excitation parameters. The power excitation parameters include power amplitude, power frequency and application time.

10. A non-volatile computer storage medium storing computer-executable instructions, characterized in that, The computer-executable instructions are set as follows: Obtain the filler orientation equivalent circuit corresponding to the filler orientation during the composite material preparation process under the excitation of an external AC power source, so as to determine the actual input energy of the external AC power source during the filler orientation process by using the power parameters of the external AC power source obtained in advance and the filler orientation equivalent circuit, wherein the actual input energy is related to the voltage application time; A pre-constructed numerical model corresponding to the composite material is obtained. The particle motion of the composite material is simulated using the numerical model and the external AC power supply parameters to obtain the particle motion parameters during the filler orientation process. The numerical model includes the rotational dynamics equation corresponding to the particle rotation process and the attraction dynamics equation corresponding to the particle attraction process. Based on the particle motion parameters during the packing orientation process, the packing orientation energy required by the particles under the AC electric field of the applied AC power supply is determined, wherein the packing orientation energy required includes the particle rotation energy and the particle attraction energy. Based on the actual input energy of the external AC power supply and the energy required for the filler orientation process, an orientation degree evaluation index is generated, wherein the orientation degree evaluation index is used to represent the fully oriented state of the composite material; Based on the orientation evaluation index, the power excitation parameters of the applied AC power supply are determined so as to regulate the preparation process of the composite material by changing the power excitation parameters. The power excitation parameters include power amplitude, power frequency and application time.

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