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20160302 Daily Question: How to calculate inductance?
Impedance (ohm) = 2 * 3.14159 * F (operating frequency) * inductance (mH)
First method: To determine its inductance, use the following formula: Impedance (ohms) = 2 * 3.14159 * F (operating frequency) * Inductance (mH). If an impedance of 360 ohms is required, then: Inductance (mH) = Impedance (ohms) ÷ (2*3.14159) ÷ F (operating frequency) = 360 ÷ (2*3.14159) ÷ 7.06 = 8.116 mH. Based on this, the number of turns in the coil can be calculated as: Number of turns = Diameter of the coil (inches) ÷ 2.047 = 19 turns.
Second method: The formula for calculating an air-core inductor is: L (mH) = (0.08 * D * D * N * N) / (3 * D + 9 * W + 10 * H), where D represents the diameter of the coil, N represents the number of turns, d represents the wire diameter, and H represents the height of the coil. The units are millimeters and mH respectively. Third method: Formula for calculating the inductance of a hollow coil: l = (0.01 * D * N * N) / (L/D + 0.44). The unit for inductance l is microhenries; the unit for coil diameter D is centimeters; the unit for the number of turns N is turns; and the unit for coil length L is centimeters. Fourth method: Formula for calculating inductance and capacitance at a given frequency: l = 25330.3 / working frequency f0, where the unit for f0 is MHz. In this case, f0 = 125 KHZ = 0.125. The unit for resonant capacitance c is picofarads; it is recommended to set c between 500 and 1000 pF, either based on personal judgment or determined by the Q value. The unit for resonant inductance l is microhenries. Fifth method: Formulas for calculating coil inductance. For toroidal cores, the following formulas can be used: L = N² * AL. Here, L represents the inductance value in henries; H-DC = 0.4πNI / l, where N is the number of turns and AL is the inductance coefficient. H-DC also represents the direct current magnetizing force, I is the current flowing through the coil in amperes, and l is the length of the magnetic circuit in centimeters. The values of l and AL can be found using the Micrometal reference table. For example, using material T50-52 with 5.5 turns of wire, the L value for T50-52 (with an OD of 0.5 inches) is approximately 33 nH according to tables; thus L = 33 × (5.5)² = 998.25 nH ≈ 1 μH. When a current of 10 A flows through it, the change in the L value can be calculated using l = 3.74 (as per tables), and H-DC = 0.4πNI/l = 0.4 × 3.14 × 5.5 × 10 / 3.74 = 18.47 (as determined from tables); this value shows the degree of decrease in the L value in μH%. 2. An empirical formula is given as L = (k * μ0 * μs * N² * S) / l, where μ0 is the permeability of free space, equal to 4π × 10⁻⁷. (10 to the power of negative 7) μs is the relative permeability of the magnetic core inside the coil; for a hollow coil, μs = 1. N2 is the square of the number of turns in the coil. S is the cross-sectional area of the coil, measured in square meters. l is the length of the coil, measured in meters. k is a coefficient that depends on the ratio of the coil’s radius (R) to its length (l). The unit of the calculated inductance is henry. K-value table: 2R/l, k = 0.1: 0.96; 0.2: 0.92; 0.3: 0.88; 0.4: 0.85; 0.6: 0.79; 0.8: 0.74; 1.0: 0.69; 1.5: 0.6; 2.0: 0.52; 3.0: 0.43; 4.0: 0.37; 5.0: 0.32; 10: 0.2; 20: 0.12
Second method: The formula for calculating an air-core inductor is: L (mH) = (0.08 * D * D * N * N) / (3 * D + 9 * W + 10 * H), where D represents the diameter of the coil, N represents the number of turns, d represents the wire diameter, and H represents the height of the coil. The units are millimeters and mH respectively. Third method: Formula for calculating the inductance of a hollow coil: l = (0.01 * D * N * N) / (L/D + 0.44). The unit for inductance l is microhenries; the unit for coil diameter D is centimeters; the unit for the number of turns N is turns; and the unit for coil length L is centimeters. Fourth method: Formula for calculating inductance and capacitance at a given frequency: l = 25330.3 / working frequency f0, where the unit for f0 is MHz. In this case, f0 = 125 KHZ = 0.125. The unit for resonant capacitance c is picofarads; it is recommended to set c between 500 and 1000 pF, either based on personal judgment or determined by the Q value. The unit for resonant inductance l is microhenries. Fifth method: Formulas for calculating coil inductance. For toroidal cores, the following formulas can be used: L = N² * AL. Here, L represents the inductance value in henries; H-DC = 0.4πNI / l, where N is the number of turns and AL is the inductance coefficient. H-DC also represents the direct current magnetizing force, I is the current flowing through the coil in amperes, and l is the length of the magnetic circuit in centimeters. The values of l and AL can be found using the Micrometal reference table. For example, using material T50-52 with 5.5 turns of wire, the L value for T50-52 (with an OD of 0.5 inches) is approximately 33 nH according to tables; thus L = 33 × (5.5)² = 998.25 nH ≈ 1 μH. When a current of 10 A flows through it, the change in the L value can be calculated using l = 3.74 (as per tables), and H-DC = 0.4πNI/l = 0.4 × 3.14 × 5.5 × 10 / 3.74 = 18.47 (as determined from tables); this value shows the degree of decrease in the L value in μH%. 2. An empirical formula is given as L = (k * μ0 * μs * N² * S) / l, where μ0 is the permeability of free space, equal to 4π × 10⁻⁷. (10 to the power of negative 7) μs is the relative permeability of the magnetic core inside the coil; for a hollow coil, μs = 1. N2 is the square of the number of turns in the coil. S is the cross-sectional area of the coil, measured in square meters. l is the length of the coil, measured in meters. k is a coefficient that depends on the ratio of the coil’s radius (R) to its length (l). The unit of the calculated inductance is henry. K-value table: 2R/l, k = 0.1: 0.96; 0.2: 0.92; 0.3: 0.88; 0.4: 0.85; 0.6: 0.79; 0.8: 0.74; 1.0: 0.69; 1.5: 0.6; 2.0: 0.52; 3.0: 0.43; 4.0: 0.37; 5.0: 0.32; 10: 0.2; 20: 0.12
First method: To determine its inductance, use the following formula: Impedance (ohms) = 2 * 3.14159 * F (operating frequency) * Inductance (mH). If an impedance of 360 ohms is required, then: Inductance (mH) = Impedance (ohms) ÷ (2*3.14159) ÷ F (operating frequency) = 360 ÷ (2*3.14159) ÷ 7.06 = 8.116 mH. Based on this, the number of turns in the coil can be calculated as: Number of turns = Diameter of the coil (inches) ÷ 2.047 = 19 turns.
Second method: The formula for calculating an air-core inductor is: L (mH) = (0.08 * D * D * N * N) / (3 * D + 9 * W + 10 * H), where D represents the diameter of the coil, N represents the number of turns, d represents the wire diameter, and H represents the height of the coil. The units are millimeters and mH respectively.
Second method: The formula for calculating an air-core inductor is: L (mH) = (0.08 * D * D * N * N) / (3 * D + 9 * W + 10 * H), where D represents the diameter of the coil, N represents the number of turns, d represents the wire diameter, and H represents the height of the coil. The units are millimeters and mH respectively.
Formula for calculating a hollow inductor: L (mH) = (0.08D × D × N × N) / (3D + 9W + 10H), where D is the coil diameter, N is the number of turns in the coil, d is the wire diameter, and H is the height of the coil. W represents the width of the coil. The units are millimeters and mH respectively.
First method: To determine its inductance, use the following formula: Impedance (ohms) = 2 * 3.14159 * F (operating frequency) * Inductance (mH). If an impedance of 360 ohms is required, then: Inductance (mH) = Impedance (ohms) ÷ (2*3.14159) ÷ F (operating frequency) = 360 ÷ (2*3.14159) ÷ 7.06 = 8.116 mH. Based on this, the number of turns in the coil can be calculated as: Number of turns = Diameter of the coil (inches) ÷ 2.047 = 19 turns.
Second method: The formula for calculating an air-core inductor is: L (mH) = (0.08 * D * D * N * N) / (3 * D + 9 * W + 10 * H), where D represents the diameter of the coil, N represents the number of turns, d represents the wire diameter, and H represents the height of the coil. The units are millimeters and mH respectively. Third method: Formula for calculating the inductance of a hollow coil: l = (0.01 * D * N * N) / (L/D + 0.44). The unit for inductance l is microhenries; the unit for coil diameter D is centimeters; the unit for the number of turns N is turns; and the unit for coil length L is centimeters. Fourth method: Formula for calculating inductance and capacitance at a given frequency: l = 25330.3 / working frequency f0, where the unit for f0 is MHz. In this case, f0 = 125 KHZ = 0.125. The unit for resonant capacitance c is picofarads; it is recommended to set c between 500 and 1000 pF, either based on personal judgment or determined by the Q value. The unit for resonant inductance l is microhenries. Fifth method: Formulas for calculating coil inductance. For toroidal cores, the following formulas can be used: L = N² * AL. Here, L represents the inductance value in henries; H-DC = 0.4πNI / l, where N is the number of turns and AL is the inductance coefficient. H-DC also represents the direct current magnetizing force, I is the current flowing through the coil in amperes, and l is the length of the magnetic circuit in centimeters. The values of l and AL can be found using the Micrometal reference table. For example, using material T50-52 with 5.5 turns of wire, the L value for T50-52 (with an OD of 0.5 inches) is approximately 33 nH according to tables; thus L = 33 × (5.5)² = 998.25 nH ≈ 1 μH. When a current of 10 A flows through it, the change in the L value can be calculated using l = 3.74 (as per tables), and H-DC = 0.4πNI/l = 0.4 × 3.14 × 5.5 × 10 / 3.74 = 18.47 (as determined from tables); this value shows the degree of decrease in the L value in μH%. 2. An empirical formula is given as L = (k * μ0 * μs * N² * S) / l, where μ0 is the permeability of free space, equal to 4π × 10⁻⁷. (10 to the power of negative 7) μs is the relative permeability of the magnetic core inside the coil; for a hollow coil, μs = 1. N2 is the square of the number of turns in the coil. S is the cross-sectional area of the coil, measured in square meters. l is the length of the coil, measured in meters. k is a coefficient that depends on the ratio of the coil’s radius (R) to its length (l). The unit of the calculated inductance is henry.
Second method: The formula for calculating an air-core inductor is: L (mH) = (0.08 * D * D * N * N) / (3 * D + 9 * W + 10 * H), where D represents the diameter of the coil, N represents the number of turns, d represents the wire diameter, and H represents the height of the coil. The units are millimeters and mH respectively. Third method: Formula for calculating the inductance of a hollow coil: l = (0.01 * D * N * N) / (L/D + 0.44). The unit for inductance l is microhenries; the unit for coil diameter D is centimeters; the unit for the number of turns N is turns; and the unit for coil length L is centimeters. Fourth method: Formula for calculating inductance and capacitance at a given frequency: l = 25330.3 / working frequency f0, where the unit for f0 is MHz. In this case, f0 = 125 KHZ = 0.125. The unit for resonant capacitance c is picofarads; it is recommended to set c between 500 and 1000 pF, either based on personal judgment or determined by the Q value. The unit for resonant inductance l is microhenries. Fifth method: Formulas for calculating coil inductance. For toroidal cores, the following formulas can be used: L = N² * AL. Here, L represents the inductance value in henries; H-DC = 0.4πNI / l, where N is the number of turns and AL is the inductance coefficient. H-DC also represents the direct current magnetizing force, I is the current flowing through the coil in amperes, and l is the length of the magnetic circuit in centimeters. The values of l and AL can be found using the Micrometal reference table. For example, using material T50-52 with 5.5 turns of wire, the L value for T50-52 (with an OD of 0.5 inches) is approximately 33 nH according to tables; thus L = 33 × (5.5)² = 998.25 nH ≈ 1 μH. When a current of 10 A flows through it, the change in the L value can be calculated using l = 3.74 (as per tables), and H-DC = 0.4πNI/l = 0.4 × 3.14 × 5.5 × 10 / 3.74 = 18.47 (as determined from tables); this value shows the degree of decrease in the L value in μH%. 2. An empirical formula is given as L = (k * μ0 * μs * N² * S) / l, where μ0 is the permeability of free space, equal to 4π × 10⁻⁷. (10 to the power of negative 7) μs is the relative permeability of the magnetic core inside the coil; for a hollow coil, μs = 1. N2 is the square of the number of turns in the coil. S is the cross-sectional area of the coil, measured in square meters. l is the length of the coil, measured in meters. k is a coefficient that depends on the ratio of the coil’s radius (R) to its length (l). The unit of the calculated inductance is henry.
This post was last edited by wang*nhua77020 on 2016-3-2 at 17:40. First method: To determine its inductance, use the following formula: Inductance (mH) = Impedance (ohms) ÷ (2*3.14159) ÷ F (operating frequency). Second method: Formula for calculating an air-core inductor: L (mH) = (0.08*D*D*N*N) / (3*D + 9*W + 10*H), where D represents the coil diameter, N represents the number of turns in the coil, d represents the wire diameter, and H represents the height of the coil. The units are millimeters and mH respectively. Third method: Formula for calculating the inductance of a hollow coil: l = (0.01 * D * N * N) / (L/D + 0.44). The unit for inductance l is microhenries; the diameter of the coil D is in cm, the number of turns N is also in turns, and the length of the coil L is in cm. Fourth method: Formula for calculating inductance and capacitance at a given frequency: l = 25330.3 / working frequency f0, where the unit for f0 is MHz. In this case, f0 = 125 KHZ = 0.125. The resonant capacitance c is in picofarads; it is recommended to set c between 500 and 1000 pF, either by choice or based on the Q value. The resonant inductance l is in microhenries. Fifth method: Formulas for calculating coil inductance. For toroidal cores, the following formula can be used: (IRON)L = N² * AL. Here, L represents the inductance value in henries; H-DC = 0.4πNI / l, where N is the number of turns, AL is the permeability coefficient, H-DC represents the direct current magnetizing force, I is the current flowing through the coil in amperes, and l is the length of the magnetic circuit in cm. The values of l and AL determine…
First method: To determine its inductance, use the following formula: Impedance (ohms) = 2 * 3.14159 * F (operating frequency) * Inductance (mH). If an impedance of 360 ohms is desired, then: Inductance (mH) = Impedance (ohms) ÷ (2*3.14159) ÷ F (operating frequency) = 360 ÷ (2*3.14159) ÷ 7.06 = 8.116 mH. Using this value, the number of turns in the coil can be calculated as follows: Number of turns = Circumference ÷ Diameter of coil (inches). Number of turns = Circumference ÷ 2.047 = 19 turns.
Second method: The formula for calculating an air-core inductor is: L (mH) = (0.08 * D * D * N * N) / (3 * D + 9 * W + 10 * H), where D represents the diameter of the coil, N represents the number of turns, d represents the wire diameter, and H represents the height of the coil. The units are millimeters for D, N, and d, and mH for H. Third method: Formula for calculating the inductance of a hollow coil: l = (0.01 * D * N * N) / (L/D + 0.44). The unit for coil inductance l is microhenries; the unit for coil diameter D is centimeters; the unit for the number of turns in the coil N is turns; and the unit for coil length L is centimeters. Fourth method: Formula for calculating inductance and capacitance at a certain frequency: l = 25330.3 / working frequency f0, with the unit being MHz; the unit for resonant capacitance c is picofarads; and the unit for resonant inductance l is microhenries. Fifth method: For ring-shaped cores, the following formula can be used to calculate coil inductance: L = N² * AL. Here, L represents the inductance value in henries; H-DC = 0.4πNI / l, where N is the number of turns in the coil, AL is the inductance coefficient, H-DC represents the direct current magnetizing force, I is the current flowing through the coil in amperes, and l is the length of the magnetic circuit in centimeters. The values of l and AL can be found using the Micrometal reference table. For example, using material T50-52 with 5.5 turns of wire, the L value for T50-52 (with an OD of 0.5 inches) is approximately 33 nH according to the tables. Thus, L = 33 × (5.5)² = 998.25 nH ≈ 1 μH. When a current of 10 A flows through it, the change in the L value can be calculated using the formula l = 3.74 (as per the tables); H-DC = 0.4πNI / l = 0.4 × 3.14 × 5.5 × 10 / 3.74 = 18.47 (as determined from the tables). This value indicates the degree of decrease in the L value in μH%
Second method: The formula for calculating an air-core inductor is: L (mH) = (0.08 * D * D * N * N) / (3 * D + 9 * W + 10 * H), where D represents the diameter of the coil, N represents the number of turns, d represents the wire diameter, and H represents the height of the coil. The units are millimeters for D, N, and d, and mH for H. Third method: Formula for calculating the inductance of a hollow coil: l = (0.01 * D * N * N) / (L/D + 0.44). The unit for coil inductance l is microhenries; the unit for coil diameter D is centimeters; the unit for the number of turns in the coil N is turns; and the unit for coil length L is centimeters. Fourth method: Formula for calculating inductance and capacitance at a certain frequency: l = 25330.3 / working frequency f0, with the unit being MHz; the unit for resonant capacitance c is picofarads; and the unit for resonant inductance l is microhenries. Fifth method: For ring-shaped cores, the following formula can be used to calculate coil inductance: L = N² * AL. Here, L represents the inductance value in henries; H-DC = 0.4πNI / l, where N is the number of turns in the coil, AL is the inductance coefficient, H-DC represents the direct current magnetizing force, I is the current flowing through the coil in amperes, and l is the length of the magnetic circuit in centimeters. The values of l and AL can be found using the Micrometal reference table. For example, using material T50-52 with 5.5 turns of wire, the L value for T50-52 (with an OD of 0.5 inches) is approximately 33 nH according to the tables. Thus, L = 33 × (5.5)² = 998.25 nH ≈ 1 μH. When a current of 10 A flows through it, the change in the L value can be calculated using the formula l = 3.74 (as per the tables); H-DC = 0.4πNI / l = 0.4 × 3.14 × 5.5 × 10 / 3.74 = 18.47 (as determined from the tables). This value indicates the degree of decrease in the L value in μH%