Design method based on ferrite circulator

Abstract

The invention provides a design method based on a ferrite circulator, which belongs to the field of circulator design, and comprises the following steps: firstly, determining magnetic track design parameters of the ferrite circulator according to preset electromagnetic performance requirements, then selecting ferrite materials, and selecting the ferrite material with proper performance based on the magnetic track design parameters. And calculating and simulating to obtain the optimal shape and size of the ferrite circulator according to the selected ferrite material and magnetic track design parameters. And then manufacturing the ferrite circulator by adopting a powder metallurgy method, and finally carrying out comprehensive performance tests including magnetic performance tests and electrical performance tests. According to the method, the design process of the ferrite circulator is integrated, so that the design parameters are accurate, the part selection is relatively accurate, the whole production process is controllable, and the performance and the production efficiency of the ferrite circulator are greatly improved.

Description

Technical Field

[0001] The invention belongs to the field of circulator design, and more specifically relates to a design method based on a ferrite circulator. Background Art

[0002] Ferrite circulator is an important magnetic component in electronic devices. It has the advantages of small size, low loss, high magnetic permeability, etc. It is widely used in electronic equipment with electromagnetic shielding requirements. For example, ferrite circulators are used in power converters, switching power supplies, filters, inductors, etc. By optimizing the design of ferrite circulators, the performance and reliability of electronic equipment can be improved.

[0003] At present, the design technology of ferrite circulators mainly focuses on material selection, shape design and process manufacturing. Material selection mainly involves selecting suitable ferrite materials, shape design mainly considers the actual application requirements of ferrite circulators, and process manufacturing mainly determines the manufacturing method of ferrite circulators. However, the interrelationships and influences between various links are relatively complex, requiring a deep understanding and mastery of electromagnetism, materials science and technology.

[0004] However, there are still some problems in the current design technology of ferrite circulators. For example, most design processes are relatively complicated, requiring calculation and simulation of each link in the design process, and it is difficult to select and optimize appropriate design parameters. In addition, there is a lack of effective performance testing methods to verify and evaluate the design scheme. Therefore, a design method based on ferrite circulators is urgently needed to solve the above problems. Summary of the invention

[0005] The present invention aims to provide a design method based on a ferrite circulator, which can accurately control the track design parameters, effectively select ferrite materials, accurately design the shape and size, and use powder metallurgy to manufacture the circulator. Finally, a comprehensive performance test is performed on the manufactured circulator, thereby achieving the purpose of optimizing the performance of the ferrite circulator, simplifying the design process, reducing the design difficulty and improving production efficiency.

[0006] In order to achieve the above object, the present invention is implemented by adopting the following technical scheme: the design method comprises:

[0007] According to the predetermined electromagnetic performance requirements, the track design parameters of the ferrite circulator are determined, including magnetic path length, cross-sectional area, track width and magnetic material.

[0008] Select ferrite materials. Based on the track design parameters, select ferrite materials with appropriate magnetic properties;

[0009] The shape and size of the ferrite circulator are designed, and the optimal shape and size of the ferrite circulator are obtained through calculation and simulation according to the ferrite material and the predetermined track design parameters.

[0010] The ferrite circulator is manufactured by powder metallurgy;

[0011] Conduct performance tests on ferrite circulators, including magnetic performance tests and electrical performance tests.

[0012] In one embodiment, the track design parameters include:

[0013] Determine the operating frequency of the ferrite circulator;

[0014] Determine the required magnetic flux density B and obtain it through the following formula:

[0015] B=Φ / A

[0016] Where Φ is the magnetic flux and A is the cross-sectional area of ​​the magnetic circuit.

[0017] Determine the size of the track, including the magnetic path length l and the cross-sectional area A, by calculating the following formula:

[0018] A=Φ / B

[0019] l=V / A

[0020] Where V is the volume of the ferrite circulator.

[0021] In one embodiment, the selection of ferrite material comprises:

[0022] Analyze the track design requirements, including saturation magnetic induction intensity Bs, magnetic permeability μ, remanence Br, and coercive force Hc; analyze the ferrite material properties, including saturation magnetic induction intensity, magnetic permeability, and frequency characteristics;

[0023] The ferrite material is selected as nickel-zinc ferrite;

[0024] Verify material selection. Use simulation to verify whether the selected ferrite material meets the magnetic track design requirements. If not, it needs to be reselected. Use the following basic magnetic circuit formula:

[0025] Φ=B*A

[0026]

[0027] Among them, Φ is the magnetic flux, B is the magnetic flux density, A is the cross-sectional area of ​​the magnetic path, R is the magnetic resistance, l is the length of the magnetic path, and μ is the magnetic permeability of the selected ferrite material.

[0028] In one embodiment, the design of the shape and size of the ferrite circulator includes:

[0029] Design the shape, determine the shape of the ferrite circulator, and choose it according to the spatial layout of the system and the impact on the electromagnetic performance. In the determined shape, the magnetic path length is proportional to the main dimensions of the ferrite circulator;

[0030] Calculate the size. According to the volume formula V=Al and the magnetic circuit formula Φ=BA of the ferrite circulator, solve this set of equations to obtain the required magnetic circuit cross-sectional area A and path length l. Here A and l are geometric parameters, representing the cross-sectional area and magnetic circuit length respectively, V is the volume, Φ is the magnetic flux, and B is the magnetic flux density;

[0031] Through the finite element analysis (FEA) software, the design parameters are input into the model for simulation to verify whether the design meets the performance requirements. If not, the design parameters are adjusted according to the simulation results and the simulation is performed again until the requirements are met.

[0032] In one embodiment, the method for making the oxygen circulator comprises:

[0033] Select raw materials: select nickel, zinc and iron powder as raw materials, and the mass ratio of nickel, zinc and iron powder is set to 4:1.6:4.4;

[0034] Proportional mixing: Mix the selected raw materials and add organic binder. The ratio of raw materials to organic binder is 5:1. The mixing process should be maintained for at least 30 minutes to ensure sufficient mixing.

[0035] The mixture is compressed under a pressure of 300 MPa to form the desired annular shape;

[0036] Sintering: Place the compressed material into a vacuum sintering furnace, heat it to 1200°C, keep it for 3 hours, and then cool it down to room temperature.

[0037] In one embodiment, the performance test includes:

[0038] Coercive force measurement: To measure the coercive force of the circulator, connect the circulator to a coil, apply an external magnetic field, and then observe the remaining magnetic induction intensity in the circulator when the magnetic field drops to zero. The coercive force is calculated using the formula Hc=Br / μ0 (where μ0 is the vacuum magnetic permeability);

[0039] Magnetic induction intensity measurement: While measuring the coercive force, the magnetic induction intensity B can also be measured; under a given current, by measuring the magnetic field intensity H of the coil, and then according to the formula

[0040] B = μH, μ is the relative magnetic permeability, calculate the magnetic induction intensity B;

[0041] Electrical performance measurement: Apply alternating current to the circulator and measure the relationship between impedance and frequency, thereby obtaining its electrical properties of conductivity, resistance and dielectric constant;

[0042] Impedance: The formula is Where Z is impedance, R is resistance, and X is reactivity;

[0043] Conductivity: The formula is Where σ is conductivity and ρ is resistivity;

[0044] Resistance: The formula is Where R is the resistance, ρ is the resistivity, L is the resistor length, and A is the cross-sectional area;

[0045] Dielectric constant: The formula is C=E / d, where C is the capacitance, E is the energy of the medium in the electric field, and d is the distance between the plates.

[0046] Beneficial effects of the present invention:

[0047] The present invention provides a design method based on a ferrite circulator. The method can first determine the design parameters according to the predetermined electromagnetic performance requirements, then select the ferrite material and adjust the track design parameters, then design the shape and size of the ferrite circulator according to the determined parameters, then use the powder metallurgy method to manufacture the circulator, and finally perform a performance test on it. The design method accurately controls the track design, material selection and size design, optimizes the entire design process, and can produce a ferrite circulator with superior performance and electromagnetic performance that meets the standards, making the design process more efficient and simplified, reducing the design difficulty and production cost, and greatly improving product performance and production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 is a flow chart of the method of the present invention;

[0049] Figure 2 Flowchart for designing the shape and size of a ferrite circulator for the present invention. DETAILED DESCRIPTION

[0050] In order to facilitate understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Typical embodiments of the present invention are provided in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in the present invention. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0051] Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0052] Embodiment 1:

[0053] The design method based on a ferrite circulator comprises:

[0054] S1. According to the predetermined electromagnetic performance requirements, determine the track design parameters of the ferrite circulator, including magnetic path length, cross-sectional area, track width and magnetic material, etc.

[0055] First, it is necessary to determine the operating frequency of the ferrite circulator in the application. The operating frequency of the ferrite circulator directly affects its performance, such as magnetic flux density, magnetic resistance and magnetic permeance.

[0056] Next, determine the required magnetic flux density (B). Generally speaking, the magnitude of the magnetic flux density directly affects the power transmission capability of the ferrite circulator. It can be calculated using the following formula: B = Φ / A

[0057] Where Φ is the magnetic flux and A is the cross-sectional area of ​​the magnetic circuit.

[0058] Then, determine the size of the magnetic track. This includes the magnetic path length (l) and cross-sectional area (A), which determines the volume and shape of the ferrite circulator. It can be calculated using the following formula:

[0059] l=V / A

[0060] Where V is the volume of the ferrite circulator.

[0061] S2. Select ferrite material. Based on the track design parameters, select ferrite material with appropriate magnetic properties.

[0062] The selected ferrite material comprises:

[0063] Analyze the track design requirements, including saturation magnetic induction intensity Bs, magnetic permeability μ, remanence Br, and coercive force Hc based on the obtained track design requirements; analyze the ferrite material properties, including saturation magnetic induction intensity, magnetic permeability, and frequency characteristics.

[0064] The saturation magnetic flux density Bs represents the limit value of the magnetic flux density generated by the ferrite circulator when the external magnetic field is extremely large. If this value is exceeded, the magnetic flux density will no longer increase with the increase of the external magnetic field.

[0065] The magnetic permeability μ describes the degree of response of the ferrite circulator to the magnetic field, that is, the ratio of the magnetic induction intensity generated by the ferrite circulator to the strength of the external magnetic field under the action of the external magnetic field. The greater the magnetic permeability, the stronger the response of the ferrite circulator to the magnetic field.

[0066] Remanence Br indicates the magnetic induction intensity that the ferrite circulator still maintains after the external magnetic field is removed. The larger the remanence, the better the magnetic memory of the ferrite circulator.

[0067] Coercive force Hc refers to the external magnetic field intensity required to reduce the magnetic induction intensity of the ferrite circulator from the saturation state to zero. The larger this parameter is, the stronger the ferrite circulator's ability to maintain magnetism is.

[0068] Frequency characteristics refer to the changes in the electromagnetic performance of ferrite circulators at different frequencies. Some ferrite materials have serious performance degradation at high frequencies. By analyzing the frequency characteristics, we can better select the appropriate materials and design solutions.

[0069] According to the analysis results, select the ferrite material that meets the track design requirements from the ferrite material library. Different ferrite materials have different electromagnetic properties and need to be considered comprehensively. The ferrite material selected is nickel-zinc ferrite.

[0070] Verify material selection. Use simulation to verify whether the selected ferrite material meets the magnetic track design requirements. If not, it needs to be reselected. Use the following basic magnetic circuit formula:

[0071] Φ=B*A

[0072]

[0073] Among them, Φ is the magnetic flux, B is the magnetic flux density, A is the cross-sectional area of ​​the magnetic path, R is the magnetic resistance, l is the length of the magnetic path, and μ is the magnetic permeability of the selected ferrite material.

[0074] S3. Design the shape and size of the ferrite circulator. According to the ferrite material and the predetermined magnetic track design parameters, the optimal shape and size of the ferrite circulator are obtained through calculation and simulation.

[0075] like Figure 2 As shown, the shape and size of the designed ferrite circulator include:

[0076] S301, determine the design parameters. First, collect and confirm the results in S1 and S2, including magnetic flux density, magnetic path length, cross-sectional area, track width, operating frequency, and performance parameters of the selected ferrite material.

[0077] S302, designing a shape, and selecting a shape for the ferrite circulator. The selection should be based on the spatial layout of the system and the impact on electromagnetic performance. In the determined shape, the magnetic path length is proportional to the main dimensions of the ferrite circulator.

[0078] S303. Calculate the size. According to the volume formula V=Al and the magnetic circuit formula Φ=BA of the ferrite circulator, solving this set of equations can obtain the required magnetic circuit cross-sectional area A and path length l. Here A and l are geometric parameters, representing the cross-sectional area and magnetic circuit length respectively, V is the volume, Φ is the magnetic flux, and B is the magnetic flux density.

[0079] S304, using finite element analysis (FEA), inputting the design parameters into the model for simulation through finite element analysis (FEA) software to verify whether the design meets the performance requirements. If not, adjusting the design parameters according to the simulation results and simulating again until the requirements are met.

[0080] S4. Use powder metallurgy to manufacture ferrite circulator.

[0081] The above design steps are mainly for the calculation and simulation of the design parameters of the ferrite circulator, such as the determination of the track design parameters, the selection of ferrite materials, and the design of the circulator shape and size. The main goal of these steps is to determine a design scheme for the ferrite circulator that can theoretically meet the electromagnetic performance requirements.

[0082] After these design steps are determined, the ferrite circulator still needs to be actually manufactured, which involves the manufacturing process of the ferrite circulator. The steps of selecting raw materials, mixing, compressing, sintering, etc. are the actual operation process of manufacturing the ferrite circulator. The mass ratio setting and the determination of mixing, compressing, and sintering conditions are all based on the aforementioned design parameters.

[0083] That is to say, the previous design step is a theoretical design, which determines the parameters and conditions that need to be followed in manufacturing the ferrite circulator, while this step is the actual operation, which is to carry out the actual manufacturing process according to the design requirements. The two are interrelated, the former determines the operating conditions of the latter, and the operating results of the latter can verify whether the design of the former is correct.

[0084] The method for making the oxygen circulator comprises:

[0085] a. Select raw materials: Select high-purity nickel, zinc and iron powders as raw materials. Assuming the required total mass is 100g, the mass ratio of nickel, zinc and iron powders can be set to 4:1.6:4.4, that is, 40g nickel, 16g zinc and 44g iron.

[0086] b. Proportional mixing: Mix the selected raw materials according to a certain mass ratio of nickel, zinc and iron, and add about 20g of organic binder to increase the viscosity of the mixture. The mixing process must be carried out under dust-proof facilities and maintained for at least 30 minutes to ensure sufficient mixing.

[0087] c. Compression molding: The mixture is compressed at a pressure of about 300 MPa to form the desired annular shape.

[0088] d. Sintering: Place the compressed material into a vacuum sintering furnace, heat it to about 1200°C, keep it warm for about 3 hours, and then cool it down to room temperature.

[0089] e. Cooling vibration: The cooled product is relaxed under cooling vibration conditions. S5. Perform performance tests on the ferrite circulator, including magnetic performance tests and electrical performance tests.

[0090] The performance tests described include:

[0091] Coercive force measurement: To measure the coercive force of the circulator, connect the circulator to a coil, apply an external magnetic field, and then observe the remaining magnetic induction intensity in the circulator when the magnetic field drops to zero. The coercive force is calculated using the formula Hc=Br / μ0 (where μ0 is the vacuum magnetic permeability).

[0092] Magnetic induction intensity measurement: While measuring the coercive force, the magnetic induction intensity B can also be measured. Under a given current, by measuring the magnetic field intensity H of the coil, and then according to the formula

[0093] B = μH, μ is the relative magnetic permeability, calculate the magnetic induction intensity B;

[0094] Electrical performance measurement: Apply alternating current to the circulator and measure the relationship between impedance and frequency, thereby obtaining its electrical properties of conductivity, resistance and dielectric constant.

[0095] Impedance: Impedance is the effect of resistance, capacitance, inductance and other components on the current in an AC circuit. Its formula is Where Z is impedance (in ohms), R is resistance (in ohms), and X is reactivity (inductive or capacitive) (in ohms).

[0096] Conductivity: Conductivity is a measure of a substance's ability to conduct electricity. Its formula is Where σ is the conductivity (unit: S / m) and ρ is the resistivity (unit: Ω·m).

[0097] Resistance: Resistance is the physical quantity that hinders the current in the circuit. Its formula is Where R is the resistance (in ohms), ρ is the resistivity (in Ω·m), L is the length of the resistor (in meters), and A is the cross-sectional area (in square meters). 2 ).

[0098] Dielectric constant (capacitance): In a capacitor, the dielectric constant is the charge distribution in the electric field, and its formula is C = E / d, where C is the capacitance, E is the energy of the dielectric in the electric field, and d is the distance between the plates.

[0099] Embodiment 2:

[0100] We need to design a ferrite circulator with an operating frequency of 20kHz. Assuming that the required magnetic flux density B is 500Gauss, we can calculate the magnetic flux Φ and the cross-sectional area A of the magnetic circuit by B=Φ / A.

[0101] The selected track design parameters are magnetic path length l of 5 cm and cross-sectional area A of 2.5 cm 2 , then we can calculate the volume V of the ferrite circulator through A=Φ / B and l=V / A.

[0102] Next, we select the ferrite material. Generally, we will choose nickel-zinc ferrite material because it has good magnetic properties, such as saturation magnetic induction intensity Bs, magnetic permeability μ, remanence Br, coercive force Hc, etc. Substitute the magnetic permeability μ of nickel-zinc ferrite into the formula Φ=BA and R=l / (μA) to verify whether it meets the track design requirements.

[0103] After determining the shape and size, we use the finite element analysis (FEA) software to input the design parameters for simulation. If the simulation results are too different from the expected results, we adjust the design parameters and simulate again until the requirements are met.

[0104] During the manufacturing process, we selected nickel, zinc, and iron powders as raw materials, with a mass ratio of 4:1.6:4.4, added organic matter after mixing, and mixed for 30 minutes at a ratio of 5:1, and then compressed under a pressure of 300MPa to form the required annular shape. The compressed material was then placed in a vacuum sintering furnace, heated to 1200°C, kept warm for 3 hours, and cooled to room temperature.

[0105] Finally, the fabricated ferrite circulator was subjected to performance tests, including magnetic and electrical performance tests. After the tests, the magnetic and electrical performances of the ferrite circulator both met the design requirements, indicating that the ferrite circulator design method of the present invention is effective.

Claims

1. A design method based on a ferrite circulator, characterized in that: The design method includes: According to the predetermined electromagnetic performance requirements, determine the magnetic track design parameters of the ferrite circulator, including magnetic path length, cross-sectional area, magnetic track width and magnetic materials; Select ferrite materials. Based on the track design parameters, select ferrite materials with appropriate magnetic properties; Design the shape and size of the ferrite circulator, and obtain the optimal shape and size of the ferrite circulator through calculation and simulation according to the ferrite material and the predetermined track design parameters; The ferrite circulator is manufactured by powder metallurgy; Conduct performance tests on ferrite circulators, including magnetic performance tests and electrical performance tests.

2. The design method based on a ferrite circulator according to claim 1, characterized in that: The track design parameters include: Determine the operating frequency of the ferrite circulator; Determine the required magnetic flux density B and obtain it through the following formula: B=Φ / A Among them, Φ is the magnetic flux, A is the cross-sectional area of ​​the magnetic circuit, and the cross-sectional area of ​​the magnetic circuit is obtained through objective design dimensions; Determine the size of the track, including the magnetic path length l and the cross-sectional area A, by calculating the following formula: l=V / A Where V is the volume of the ferrite circulator.

3. The design method based on ferrite circulator according to claim 1, characterized in that: The selected ferrite materials include: Analyze the track design requirements, including saturation magnetic induction intensity Bs, magnetic permeability μ, remanence Br, and coercive force Hc; analyze the ferrite material properties, including saturation magnetic induction intensity, magnetic permeability, and frequency characteristics; The ferrite material is selected as nickel-zinc ferrite; Verify material selection. Use simulation to verify whether the selected ferrite material meets the magnetic track design requirements. If not, it needs to be reselected. Use the following basic magnetic circuit formula: Φ=B*A R＝ l μ*A Among them, Φ is the magnetic flux, B is the magnetic flux density, A is the cross-sectional area of ​​the magnetic path, R is the magnetic resistance, l is the length of the magnetic path, and μ is the magnetic permeability of the selected ferrite material.

4. The design method based on a ferrite circulator according to claim 1, characterized in that: The shape and size of the designed ferrite circulator include: Design the shape, determine the shape of the ferrite circulator, and choose it according to the spatial layout of the system and the impact on the electromagnetic performance. In the determined shape, the magnetic path length is proportional to the main dimensions of the ferrite circulator; Calculate the size. According to the volume formula V=Al and the magnetic circuit formula Φ=BA of the ferrite circulator, solve this set of equations to obtain the required magnetic circuit cross-sectional area A and path length l. Here A and l are geometric parameters, representing the cross-sectional area and magnetic circuit length respectively, V is the volume, Φ is the magnetic flux, and B is the magnetic flux density; Through the finite element analysis (FEA) software, the design parameters are input into the model for simulation to verify whether the design meets the performance requirements. If not, the design parameters are adjusted according to the simulation results and simulated again until the requirements are met.

5. The design method based on ferrite circulator according to claim 1, characterized in that: The method for making the oxygen circulator comprises: Select raw materials: select nickel, zinc and iron powder as raw materials, and the mass ratio of nickel, zinc and iron powder is set to 4:1.6:4.4; Proportional mixing: Mix the selected raw materials and add organic binder. The ratio of raw materials to organic binder is 5:

1. The mixing process should be maintained for at least 30 minutes to ensure sufficient mixing. The mixture is compressed under a pressure of 300 MPa to form the desired annular shape; Sintering: Place the compressed material into a vacuum sintering furnace, heat it to 1200°C, keep it for 3 hours, and then cool it down to room temperature.

6. The design method based on ferrite circulator according to claim 1, characterized in that: The performance tests described include: Coercive force measurement: To measure the coercive force of the circulator, connect the circulator to a coil, apply an external magnetic field, and then observe the remaining magnetic induction intensity in the circulator when the magnetic field drops to zero. The coercive force is calculated using the formula Hc=Br / μ0 (where μ0 is the vacuum magnetic permeability); Magnetic induction intensity measurement: While measuring the coercive force, the magnetic induction intensity B can also be measured; under a given current, by measuring the magnetic field intensity H of the coil, and then according to the formula B = μH, μ is the relative magnetic permeability, the magnetic induction intensity B is calculated; Electrical performance measurement: Apply alternating current to the circulator and measure the relationship between impedance and frequency, thereby obtaining its electrical properties of conductivity, resistance and dielectric constant; Impedance: The formula is Where Z is impedance, R is resistance, and X is reactivity; Conductivity: The formula is Where σ is conductivity and ρ is resistivity; Resistance: The formula is Where R is the resistance, ρ is the resistivity, L is the resistor length, and A is the cross-sectional area; Dielectric constant: The formula is C=E / d, where C is the capacitance, E is the energy of the medium in the electric field, and d is the distance between the plates.

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