Size determination method of integrated inductor and related assembly

Abstract

The invention discloses a size determination method of an integrated inductor and a related assembly, and relates to the field of integrated inductor design, and the method comprises the steps: determining an equivalent magnetic circuit of a magnetic core according to the structure of the magnetic core of the integrated inductor; determining the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit; determining the sectional area of the wrapping post, the sectional area of the common magnet yoke and the sectional area of the decoupling magnet yoke according to the maximum value of the magnetic flux; determining the length of the wrapping post of each phase according to the number of turns of the winding, the maximum direct current bias current of the integrated inductor, the equivalent magnetic circuit length of the wrapping post and the equivalent magnetic circuit length of the common magnet yoke and the decoupling magnet yoke; and determining the size of the integrated inductor according to the sectional areas of the wrapping posts, the sectional areas of the common magnet yokes, the sectional areas of the decoupling magnet yokes and the length of each phase of wrapping post. The inductors are integrated, and the multiple inductors which are connected in parallel in an interleaving mode share one magnetic core, so that the size and the weight of the converter are reduced.

Description

Technical Field

[0001] The present invention relates to the field of integrated inductor design, and in particular to a method for determining the size of an integrated inductor and related components. Background Art

[0002] As the power level of multiphase power converters continues to increase, the number of inductors in interleaved parallel DC-DC converters is increasing, and the volume and weight of inductors are significantly increased, which increases the cost of power converters and reduces their power density. Interleaved parallel refers to decomposing a large periodic power source into several smaller power sources, allowing these smaller power sources to work at the same frequency with a certain phase difference. As the power level of DC-DC converters continues to increase, the voltage or current stress borne by the device is getting higher and higher, even exceeding its tolerance range, which leads to higher device costs and losses. Multiphase interleaved parallel technology has been widely used because of its advantages of reducing the voltage and current stress of the switch tube, reducing the total current ripple, increasing the capacity of the converter, and improving efficiency and power density. Although multiphase interleaved parallel technology has many advantages in improving converter efficiency and performance, it increases the number of converter magnetic components and switching devices, which limits the further improvement of converter power density. Since magnetic components account for a large proportion of the volume and weight of DC-DC converters, they have an important impact on the performance of the converter. Therefore, how to balance improving the efficiency of the converter while reducing the volume and weight of the integrated inductor is an urgent problem to be solved in the existing technology. Summary of the invention

[0003] The object of the present invention is to provide a method for determining the size of an integrated inductor and related components, by integrating the inductor and sharing a magnetic core with a plurality of inductors connected in parallel, thereby reducing the volume and weight of the converter.

[0004] In order to solve the above technical problems, the present invention provides a method for determining the size of an integrated inductor. The magnetic core of the integrated inductor includes an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding. The winding post includes a left winding post and a right winding post. The first decoupling yoke to the n-1th decoupling yoke are sequentially arranged between the upper common yoke and the lower common yoke. The upper part of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, and the lower part is connected to the i+1th phase left winding post and the i+1th phase right winding post. The upper common yoke is connected to the first phase left winding post and the first phase right winding post, respectively. The lower common yoke is connected to the n-th phase left winding post and the n-th phase right winding post, respectively. N / 2 turns of winding are wound on the left winding post and the right winding post of each phase, 1<i<n, i and n are both integers.

[0005] The method for determining the size of the integrated inductor comprises:

[0006] Determining an equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor;

[0007] determining the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit;

[0008] Determining the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common magnetic yoke, and the cross-sectional area of ​​the decoupling magnetic yoke according to the maximum value of the magnetic flux;

[0009] Determine the length of each phase winding post according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding post, and the equivalent magnetic path lengths of the common yoke and the decoupling yoke;

[0010] The size of the integrated inductor is determined according to the cross-sectional area of ​​the winding post, the cross-sectional area of ​​the common yoke, the cross-sectional area of ​​the decoupling yoke, and the length of each phase winding post.

[0011] On the other hand, determining the equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor includes:

[0012] The magnetomotive force, winding rod reluctance, common yoke reluctance and decoupled yoke reluctance in the equivalent magnetic circuit of the magnetic core are determined according to the structure of the magnetic core of the integrated inductor.

[0013] On the other hand, the magnetomotive force, winding column magnetic resistance, common magnetic yoke magnetic resistance and decoupled magnetic yoke magnetic resistance in the equivalent magnetic circuit of the magnetic core are determined according to the structure of the magnetic core of the integrated inductor, including:

[0014] Determine the connection relationship between the magnetomotive force, winding rod magnetic resistance, common magnetic yoke magnetic resistance and decoupling magnetic yoke magnetic resistance in the equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor;

[0015] The connection relationship includes the first end of the i-th decoupling yoke magnetic resistance being connected to the negative end of the i-th magnetomotive force and the first end of the i+1-th winding magnetic resistance, the positive end of the i-th magnetomotive force being connected to the first end of the i-th winding post magnetic resistance, the second end of the i-th winding post magnetic resistance being connected to the first end of the i-1-th decoupling yoke magnetic resistance, and the second end of the i-1-th decoupling yoke magnetic resistance being connected to the second end of the i-th decoupling yoke magnetic resistance; the first end of the first common yoke magnetic resistance being connected to the second end of the first winding post magnetic resistance, the second end of the first common yoke magnetic resistance being connected to the second end of each of the decoupling yoke magnetic resistances and the second end of the second common yoke magnetic resistance, the first end of the second common yoke magnetic resistance being connected to the negative end of the n-th magnetomotive force, and i is an integer greater than 1.

[0016] On the other hand, determining the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit includes:

[0017] Determine the magnetic flux of each decoupling yoke, the relationship between the magnetic flux of each phase is

[0018]

[0019] Among them, Φ1(t) is the magnetic flux between the upper common yoke and the first phase winding column, Φ n (t) is the magnetic flux between the lower common yoke and the nth phase winding pole, Φ j1 (t) is the magnetic flux of the first decoupling yoke, Φ j(n-1)1 (t) is the magnetic flux of the n-1th decoupling yoke, i L1 (t) is the current flowing through the first phase winding, i Ln (t) is the current flowing through the n-th phase winding, and R is the magnetic resistance of the winding column.

[0020] On the other hand, before determining the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common magnetic yoke and the cross-sectional area of ​​the decoupling magnetic yoke according to the maximum value of the magnetic flux, the method further includes:

[0021] Determine the maximum value of the magnetic flux, the expression of the maximum value of the magnetic flux is:

[0022]

[0023] Among them, Φ max is the maximum value of the magnetic flux, Φ dc is the DC magnetic flux, △Φ is the AC magnetic flux;

[0024] Enter the step of determining the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common yoke and the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux.

[0025] On the other hand, the process of determining the DC magnetic flux includes:

[0026] The DC magnetic flux is determined according to the number of turns of the winding wound on each phase winding pole, the maximum DC bias current, the magnetic resistance of the upper common magnetic yoke, the magnetic resistance of the lower common magnetic yoke, the magnetic resistance of the decoupling magnetic yoke and the DC magnetic flux relationship, and the DC magnetic flux relationship is:

[0027] Where R is the magnetic resistance of the winding column, R m is the magnetic resistance of each decoupling yoke, R m1 is the magnetic resistance of the upper common yoke and the lower common yoke, I dc is the maximum DC bias current, and L1 is the self-inductance of the first phase inductor.

[0028] On the other hand, the process of determining the self-inductance of the first phase inductor includes:

[0029] The self-inductance of each phase is determined according to the magnetic resistance of the winding column, the magnetic resistance of each decoupling yoke, the magnetic resistance of the upper common yoke and the magnetic resistance of the lower common yoke. The expression of the self-inductance is:

[0030] Where L1 is the self-inductance of the first phase inductor, L n is the self-inductance of the first phase inductor, R is the magnetic resistance of the winding column, R m is the magnetic resistance of each decoupling yoke, R m1 is the magnetic resistance of the upper common yoke and the lower common yoke.

[0031] On the other hand, determining the cross-sectional area of ​​the left winding column of each phase and the cross-sectional area of ​​the right winding column of each phase according to the maximum value of the magnetic flux includes:

[0032] The cross-sectional area of ​​each phase of the winding post on the XY plane is determined according to the maximum value of the magnetic flux and the maximum magnetic density of the winding post magnetic core material. The relationship between the cross-sectional area of ​​the winding post on the XY plane is:

[0033]

[0034] Among them, Φ max is the maximum value of the magnetic flux, B m1 is the maximum magnetic density of the winding core material, △Φ is the AC magnetic flux, L1 is the self-inductance of the first phase inductor, I dc is the maximum DC bias current, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle.

[0035] On the other hand, determining the cross-sectional area of ​​the common magnetic yoke according to the maximum value of the magnetic flux comprises:

[0036] The cross-sectional area of ​​the common yoke on the YZ plane of each phase is determined according to the maximum value of the magnetic flux and the maximum magnetic density of the common yoke core material. The relationship formula of the cross-sectional area of ​​the common yoke on the YZ plane is:

[0037]

[0038] Among them, Φ max is the maximum value of the magnetic flux, B m2 is the maximum magnetic density of the common yoke core material, △Φ is the AC magnetic flux, L1 is the self-inductance of the first phase inductor, I dc is the maximum DC bias current, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle.

[0039] On the other hand, determining the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux includes:

[0040] determining a maximum magnetic flux of the decoupling yoke;

[0041] The cross-sectional area of ​​the decoupling yoke on the YZ plane is determined according to the maximum magnetic flux, and the expression of the cross-sectional area is:

[0042] Among them, Φ j1max is the maximum magnetic flux of the decoupling yoke, A ej1 To A ej(n-1) is the cross-sectional area of ​​the decoupling yoke on the YZ surface, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle, B m2 It is the maximum magnetic flux density of the decoupling yoke core material.

[0043] On the other hand, the length of each phase winding post is determined according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding post, and the equivalent magnetic path lengths of the common yoke and the decoupling yoke, including:

[0044] The maximum DC bias current is determined according to the number of turns of the winding, the magnetic field strength in the winding column, the magnetic field strength in the common yoke and the decoupling yoke, the equivalent magnetic path length of the winding column, and the equivalent magnetic path length of the common yoke and the decoupling yoke. The relationship of the maximum DC bias current is H1l eq1 +H2l eq2 =NI dc ;

[0045] Wherein, H1 is the magnetic field strength in the winding column, H2 is the magnetic field strength in the common magnetic yoke and the decoupling magnetic yoke, l eq1 is the equivalent magnetic path length of the winding column, l eq2 is the equivalent magnetic path length of the common yoke and the decoupling yoke, I dc is the maximum DC bias current;

[0046] Determine the relationship between the maximum magnetic flux density of the winding column and the maximum magnetic flux density and magnetic permeability of the common magnetic yoke and the decoupling magnetic yoke. The expression of the relationship between the magnetic flux density, magnetic permeability and magnetic field strength is:

[0047] Among them, B m1is the maximum magnetic flux density of the winding column, μ1 is the magnetic permeability of the winding column, B m2 is the maximum magnetic density of the common yoke and the decoupling yoke, μ2 is the magnetic permeability of the common yoke and the decoupling yoke;

[0048] determining the magnetic resistance of the winding post according to the magnetic permeability;

[0049] The length of the winding post is determined according to the magnetic resistance of the winding post.

[0050] In order to solve the above technical problems, the present invention also provides a size determination system for an integrated inductor. The magnetic core of the integrated inductor includes an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding. The winding post includes a left winding post and a right winding post. The first decoupling yoke to the n-1th decoupling yoke are sequentially arranged between the upper common yoke and the lower common yoke. The upper part of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, and the lower part is connected to the i+1th phase left winding post and the i+1th phase right winding post. The upper common yoke is connected to the first phase left winding post and the first phase right winding post, respectively. The lower common yoke is connected to the n-th phase left winding post and the n-th phase right winding post, respectively. N / 2 turns of winding are wound on the left winding post and the right winding post of each phase, 1<i<n, i and n are both integers. The size determination system for the integrated inductor includes:

[0051] An equivalent magnetic circuit determining unit, configured to determine an equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor;

[0052] a magnetic flux determination unit, configured to determine the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit;

[0053] A cross-sectional area determination unit, configured to determine the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common yoke, and the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux;

[0054] A length determination unit, configured to determine the length of each phase winding post according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding post, and the equivalent magnetic path lengths of the common yoke and the decoupling yoke;

[0055] The size determination unit is used to determine the size of the integrated inductor according to the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common yoke, the cross-sectional area of ​​the decoupling yoke and the length of each phase winding column.

[0056] In order to solve the above technical problems, the present invention further provides a device for determining the size of an integrated inductor, comprising:

[0057] Memory for storing computer programs;

[0058] A processor is used to implement the steps of the above-mentioned method for determining the size of the integrated inductor when executing the computer program.

[0059] In order to solve the above technical problems, the present invention also provides an integrated inductor, the magnetic core of the integrated inductor includes an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding, the winding post includes a left winding post and a right winding post, the first decoupling yoke to the n-1th decoupling yoke are arranged in sequence between the upper common yoke and the lower common yoke, the upper part of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, and the lower part is connected to the i+1-th phase left winding post and the i+1-th phase right winding post, the upper common yoke is respectively connected to the first phase left winding post and the first phase right winding post, the lower common yoke is respectively connected to the n-th phase left winding post and the n-th phase right winding post, each phase left winding post and the right winding post are wound with N / 2 turns of winding, 1<i<n, i and n are both integers.

[0060] In order to solve the above technical problem, the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned method for determining the size of an integrated inductor are implemented.

[0061] The invention discloses a method for determining the size of an integrated inductor and related components, and relates to the field of integrated inductor design, including determining the equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor; determining the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit; determining the cross-sectional area of ​​the winding post, the cross-sectional area of ​​the common magnetic yoke, and the cross-sectional area of ​​the decoupling magnetic yoke according to the maximum value of the magnetic flux; determining the length of each phase winding post according to the number of turns of the winding, the maximum bias DC current of the integrated inductor, the equivalent magnetic circuit length of the winding post, and the equivalent magnetic circuit length of the common magnetic yoke and the decoupling magnetic yoke; determining the size of the integrated inductor according to the cross-sectional area of ​​the winding post, the cross-sectional area of ​​the common magnetic yoke, the cross-sectional area of ​​the decoupling magnetic yoke, and the length of each phase winding post. By integrating the inductor, a plurality of staggered parallel inductors share a magnetic core, and the volume and weight of the converter are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0063] Figure 1 A flow chart of a method for determining the size of an integrated inductor provided by the present invention;

[0064] Figure 2A front view of an n-phase staggered parallel integrated inductor provided by the present invention;

[0065] Figure 3 A schematic diagram of the structure of an n-phase interleaved parallel DC-DC converter provided by the present invention;

[0066] Figure 4 A schematic diagram of a waveform of a phase inductor current in a current continuous mode provided by the present invention;

[0067] Figure 5 A top view of an n-phase staggered parallel integrated inductor provided by the present invention;

[0068] Figure 6 A side view of an n-phase staggered parallel integrated inductor provided by the present invention;

[0069] Figure 7 A schematic diagram of an equivalent magnetic circuit of an n-phase integrated inductor provided by the present invention;

[0070] Figure 8 A schematic diagram of an equivalent magnetic circuit of an n-phase integrated inductor provided by the present invention with the magnetomotive force source other than the first phase set to zero;

[0071] Fig. 9 A diagram showing the influence of different decoupling phase sequences on the peak magnetic flux on the decoupling magnetic yoke provided by the present invention;

[0072] Fig.10 A waveform diagram of an n-phase inductor terminal voltage, magnetic flux of the left and right winding poles of the inductor, and magnetic flux of a decoupling yoke provided by the present invention;

[0073] Fig.11 A schematic diagram of the structure of a size determination system for an integrated inductor provided by the present invention;

[0074] Fig.12 A schematic diagram of the structure of a device for determining the size of an integrated inductor provided by the present invention; DETAILED DESCRIPTION

[0075] The core of the present invention is to provide a method for determining the size of an integrated inductor and related components, by integrating the inductor and allowing multiple inductors connected in parallel to share a magnetic core, thereby reducing the volume and weight of the converter.

[0076] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0077] Figure 1 A flow chart of a method for determining the size of an integrated inductor provided by the present invention, Figure 2 A front view of an n-phase staggered parallel integrated inductor provided by the present invention;

[0078] The magnetic core of the integrated inductor includes an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding, the winding post includes a left winding post and a right winding post, the first decoupling yoke to the n-1th decoupling yoke are sequentially arranged between the upper common yoke and the lower common yoke, the upper part of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, the lower part is connected to the i+1th phase left winding post and the i+1th phase right winding post, the upper common yoke is respectively connected to the first phase left winding post and the first phase right winding post, the lower common yoke is respectively connected to the n-th phase left winding post and the n-th phase right winding post, each phase left winding post and the right winding post are wound with N / 2 turns of winding, 1<i<n, i and n are both integers;

[0079] The method for determining the size of the integrated inductor includes:

[0080] S11: determining an equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor;

[0081] S12: Determine the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit;

[0082] S13: determining the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common magnetic yoke, and the cross-sectional area of ​​the decoupling magnetic yoke according to the maximum value of the magnetic flux;

[0083] S14: determining the length of each phase winding post according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding post, and the equivalent magnetic path length of the common magnetic yoke and the decoupling magnetic yoke;

[0084] S15: Determine the size of the integrated inductor according to the cross-sectional area of ​​the winding post, the cross-sectional area of ​​the common magnetic yoke, the cross-sectional area of ​​the decoupling magnetic yoke, and the length of each phase winding post.

[0085] Interleaving parallel means breaking down a larger periodic power source into several smaller power sources, allowing these smaller power sources to work at the same frequency with a certain phase difference. As the power level of DC-DC converters continues to increase, the voltage or current stress on the device is getting higher and higher, even beyond its tolerance range, which leads to higher device costs and losses. Multi-phase interleaving parallel technology has been widely used because of its advantages of reducing the voltage and current stress of the switch tube, reducing the total current ripple, increasing the capacity of the converter, and improving efficiency and power density.

[0086] Although multi-phase interleaved parallel technology has many advantages in improving converter efficiency and performance, it increases the number of converter magnetic components and switching devices, which limits the further improvement of converter power density. Since magnetic components account for a large proportion of the volume and weight of the converter and have a significant impact on the performance of the converter, it is necessary to adopt magnetic integration technology to further optimize the performance of interleaved parallel converters.

[0087] Figure 3 A schematic diagram of the structure of an n-phase interleaved parallel DC-DC converter provided by the present invention, Figure 4 A schematic diagram of a waveform of a phase inductor current in a current continuous mode provided by the present invention;

[0088] Figure 3 Middle C H , C L They are filter capacitors on the high and low voltage sides of the circuit, L1, L2…L n is the inductance of each phase, i L1 、i L2 …i Ln is the current of the inductor of each phase, i Σ is the sum of the inductor currents of each phase, u L1 、u L2 …u Ln is the voltage across the inductor of each phase. H When the input voltage is V, the topology can be regarded as n Buck circuits connected in parallel. As a step-down circuit, the output load voltage is V L MOS tubes S1, S2…S n As a power switch tube, MOS tube S n+1 , S n+2 …S 2n As a synchronous rectifier to replace the diode in the Buck circuit, it is called Buck working mode; when the low voltage side V L When the input voltage is V, the topology can be regarded as a boost circuit consisting of n Boost circuits in parallel. H , where MOS tube S n+1 , S n+2 …S 2n As power switch tubes, MOS tubes S1, S2...S n Using a synchronous rectifier to replace the diode in the Boost circuit is called the Boost operating mode.

[0089] Taking Buck mode as an example, S1, S2…S n Main power tube, S n+1 , S n+2 …S 2nAs a synchronous rectifier to replace the diode in the Buck circuit. Assume that the inductance of the first phase is L1 and the switching period is T S , the driving signal of switch tube S1 is u s1 , its duty cycle is D, and the average current of each phase inductor is I dc , the total output power is P.

[0090] like Figure 4 As shown, when the switch tube S1 is turned on, the switch tube S n+1 Cut off, at this time the voltage across the first phase inductor is positive, and its value is V i -V o , so the first phase inductor current rises, and the increment of the first phase inductor current is When the switch tube S1 is turned off, the diode S n+1 The voltage across the first phase inductor is negative, and its value is -V o , so the first-phase inductor current decreases, and the reduction in the first-phase inductor current is Therefore, the first phase inductor current ripple can be obtained as The minimum inductor current is

[0091]

[0092] The embodiment of the present application discloses a design method of an n-phase high-decoupling integrated inductor, which is used to solve the problems of excessive cost, volume and weight of the inductor structure in the existing n-phase power converter. The magnetic core of the n-phase integrated inductor includes 2 ordinary yokes, (n-1) decoupling yokes, and 2n winding poles. The yoke part adopts a magnetic material with high magnetic permeability, such as ferrite. The winding pole part adopts a magnetic material with low magnetic permeability, such as a powder core.

[0093] Figure 2 A front view of an n-phase staggered parallel integrated inductor provided by the present invention, Figure 5 A top view of an n-phase staggered parallel integrated inductor provided by the present invention, Figure 6 A side view of an n-phase staggered parallel integrated inductor provided by the present invention;

[0094] The N turns of winding of each phase are wound on the left and right winding poles, and the number of turns on the left and right winding poles is N / 2.

[0095] Among them, air gaps may be left between the left and right winding posts of the first phase and the upper common yoke and the first decoupling yoke, air gaps may be left between the left and right winding posts of the second phase and the first decoupling yoke and the second decoupling yoke, and air gaps may be left between the left and right winding posts of the nth phase and the lower common yoke and the (n-1)th decoupling yoke. The first decoupling yoke is located between the first phase and the second phase winding posts. The second decoupling yoke is located between the second phase and the third phase winding posts. The (n-1)th decoupling yoke is located between the (n-1)th phase and the nth phase winding posts. The heights of the (n-1) decoupling yokes in the Z direction are all less than the heights of the two common yokes in the Z direction. The depths of the two common yokes and the (n-1) decoupling yokes in the Y direction are greater than the depths of all winding posts in the Y direction. The core cross-sectional area of ​​the winding post on the XY plane is less than the core cross-sectional area of ​​the two common yokes on the YZ plane.

[0096] Therefore, after the integrated inductor is designed, the dimensions of each period in the integrated inductor, such as the cross-sectional area and the length, need to be designed in order to determine the dimensions of the integrated inductor.

[0097] The invention discloses a method for determining the size of an integrated inductor, and relates to the field of integrated inductor design, including determining the equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor; determining the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit; determining the cross-sectional area of ​​the winding post, the cross-sectional area of ​​the common magnetic yoke, and the cross-sectional area of ​​the decoupling magnetic yoke according to the maximum value of the magnetic flux; determining the length of each phase winding post according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic circuit length of the winding post, and the equivalent magnetic circuit length of the common magnetic yoke and the decoupling magnetic yoke; determining the size of the integrated inductor according to the cross-sectional area of ​​the winding post, the cross-sectional area of ​​the common magnetic yoke, the cross-sectional area of ​​the decoupling magnetic yoke, and the length of each phase winding post. By integrating the inductor, a plurality of staggered parallel inductors share a magnetic core, and the volume and weight of the converter are reduced.

[0098] Based on the above embodiments:

[0099] Figure 7 A schematic diagram of an equivalent magnetic circuit of an n-phase integrated inductor provided by the present invention;

[0100] Figure 8 A schematic diagram of an equivalent magnetic circuit of an n-phase integrated inductor provided by the present invention with the magnetomotive force source other than the first phase set to zero;

[0101] In some embodiments, determining an equivalent magnetic circuit of a magnetic core according to a structure of a magnetic core of an integrated inductor includes:

[0102] The equivalent magnetic circuit of the inductor is determined based on the winding rod reluctance, magnetomotive force, ordinary yoke reluctance and decoupled yoke reluctance.

[0103] In some embodiments, determining the equivalent magnetic circuit of the inductor based on the winding rod reluctance, the magnetomotive force, the common yoke reluctance and the decoupled yoke reluctance includes:

[0104] Determine the equivalent magnetic circuit of the inductor based on the winding column reluctance, magnetomotive force, ordinary yoke reluctance, decoupled yoke reluctance and connection relationship;

[0105] The connection relationship includes the first end of the i-th decoupling yoke magnetic resistance being connected to the negative end of the i-th magnetomotive force and the first end of the i+1-th winding pole magnetic resistance, the positive end of the i-th magnetomotive force being connected to the first end of the i-th winding pole magnetic resistance, the second end of the i-th winding pole magnetic resistance being connected to the first end of the i-1-th decoupling yoke magnetic resistance, and the second end of the i-1-th decoupling yoke magnetic resistance being connected to the second end of the i-th decoupling yoke magnetic resistance; the first end of the first common yoke magnetic resistance being connected to the second end of the first winding pole magnetic resistance, the second end of the first common yoke magnetic resistance being connected to the second ends of each decoupling yoke magnetic resistance and the second end of the second common yoke magnetic resistance, and the first end of the second common yoke magnetic resistance being connected to the negative end of the n-th magnetomotive force, where i is an integer greater than 1.

[0106] In some embodiments, determining the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit includes:

[0107] Determine the magnetic flux of each decoupling yoke reluctance as the magnetic flux of the corresponding phase. The relationship between the magnetic flux of each phase is:

[0108] Among them, Φ1(t) is the magnetic flux between the upper common yoke and the first phase winding column, Φ n (t) is the magnetic flux between the lower common yoke and the nth phase winding pole, Φ j1 (t) is the magnetic flux of the first decoupling yoke, Φ j(n-1) (t) is the magnetic flux of the n-1th decoupling yoke, i L1 (t) is the current flowing through the first phase winding, i Ln (t) is the current flowing through the n-th phase winding, and R is the magnetic resistance of the winding column.

[0109] Φ j1 The positive direction of (t) is Figure 2 As shown; Φ j2 The positive direction of (t) is Figure 2 As shown; R m1 is the magnetic resistance of the upper and lower common magnetic yokes, which is ideally zero due to the use of high magnetic permeability core materials; R m is the magnetic resistance of each decoupling yoke, which is ideally zero due to the use of high permeability core material. R is the total magnetic resistance of the left and right windings of each phase.

[0110] In some embodiments, before determining the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common magnetic yoke, and the cross-sectional area of ​​the decoupling magnetic yoke according to the maximum value of the magnetic flux, the method further includes:

[0111] Determine the maximum value of the magnetic flux. The expression for the maximum value of the magnetic flux is

[0112] Among them, Φ max is the maximum value of magnetic flux, Φ dc is the DC magnetic flux, △Φ is the AC magnetic flux;

[0113] Enter the step of determining the cross-sectional area of ​​the winding pole, the cross-sectional area of ​​the common yoke and the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux.

[0114] In some embodiments, the process of determining the DC magnetic flux includes:

[0115] The DC flux is determined based on the number of turns of the winding wound on each phase winding pole, the maximum DC bias current, the magnetic resistance of the upper common magnetic yoke, the magnetic resistance of the lower common magnetic yoke, the magnetic resistance of the decoupling magnetic yoke and the DC flux relationship. The DC flux relationship is:

[0116] Where R is the magnetic resistance of the winding column, R m is the magnetic resistance of each decoupling yoke, R m1 is the magnetic resistance of the upper common yoke and the lower common yoke, I dc is the maximum DC bias current, and L1 is the self-inductance of the first phase inductor.

[0117] According to the DC flux equivalent magnetic circuit diagram and the flux linkage formula, taking the first phase as an example, the DC flux Ф in the winding column and the ordinary yoke can be obtained. dc .

[0118] In some embodiments, the process of determining the self-inductance of the first phase inductor includes:

[0119] The self-inductance of each phase is determined based on the reluctance of the winding column, the reluctance of each decoupling yoke, the reluctance of the upper common yoke and the lower common yoke. The expression of self-inductance is

[0120] Where L1 is the self-inductance of the first phase, L n is the self-inductance of the nth phase, R is the magnetic resistance of the winding column, R m is the magnetic resistance of each decoupling yoke, R m1 is the magnetic resistance of the upper common yoke and the lower common yoke.

[0121] N is the number of turns of the winding of each phase inductor. m1 and R m By using high magnetic permeability materials, the magnetic resistance can be equivalent to 0; in order to obtain the coupling coefficient between the first phase and the second phase, the magnetomotive force source other than the first phase can be set to zero. At this time, the magnetic flux Ф generated by the first phase winding current on the second phase 12 The expression is Due to the magnetic resistance R of the lower common yokem1 , the magnetic resistance R of the decoupling yoke m Much smaller than the magnetic resistance R of the winding column, let L1=L2=…=L n , so the coupling coefficient expression of the first phase and the second phase is Similarly, the coupling coefficient k between the inductors of each phase is approximately equal to 0, and the decoupled integrated inductor has the characteristic of high decoupling degree. The expression of each magnetic resistance is where μ rao is the magnetic permeability of the winding rod magnetic material, l rao is the equivalent magnetic path length of each phase winding, S rao The cross-sectional area of ​​each phase winding column.

[0122] In some embodiments, determining the cross-sectional area of ​​the left winding column of each phase and the cross-sectional area of ​​the right winding column of each phase according to the maximum value of the magnetic flux includes:

[0123] The cross-sectional area of ​​each phase winding post on the XY plane is determined according to the maximum value of the magnetic flux and the maximum magnetic density of the winding post core material. The relationship between the cross-sectional area of ​​the winding post on the XY plane is:

[0124]

[0125] Among them, Φ max is the maximum value of magnetic flux, B m1 is the maximum magnetic flux density of the winding core material, △Φ is the AC magnetic flux, L1 is the self-inductance of the first phase, I dc is the maximum DC bias current, V i is the input voltage of the converter, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle.

[0126] In some embodiments, determining the cross-sectional area of ​​the common magnetic yoke according to the maximum value of the magnetic flux includes:

[0127] The cross-sectional area of ​​each phase common yoke on the YZ plane is determined according to the maximum value of magnetic flux and the maximum magnetic density of the common yoke core material. The relationship between the cross-sectional area of ​​the common yoke on the YZ plane is:

[0128]

[0129] Among them, Φ max is the maximum value of magnetic flux, B m2 is the maximum magnetic density of the common yoke core material, △Φ is the AC magnetic flux, L1 is the self-inductance of the first phase, I dc is the maximum DC bias current, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T sis the switching cycle.

[0130] Fig. 9 A diagram showing the influence of different decoupling phase sequences on the peak magnetic flux on the decoupling magnetic yoke provided by the present invention;

[0131] In some embodiments, determining the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux includes:

[0132] Determine the maximum magnetic flux of the decoupling yoke;

[0133] Determine the cross-sectional area of ​​the decoupling yoke on the YZ plane based on the maximum magnetic flux. The expression for the cross-sectional area is:

[0134]

[0135] Among them, Φ j1max is the maximum magnetic flux of the decoupling yoke, A ej1 To A ej(n-1) is the cross-sectional area of ​​the decoupling yoke on the YZ surface, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle, B m2 It is the maximum magnetic flux density of the decoupling yoke core material.

[0136] It is necessary to determine the phase sequence of the decoupling integrated inductor. Different phase sequence arrangements will result in different peak magnetic fluxes on the decoupling yoke. Fig.10 The magnetic flux waveforms of the decoupling yokes of four decoupling phase sequences are given, and the decoupling phase sequences are the first phase and the second phase, the first phase and the third phase, the first phase and the fourth phase, and the first phase and the fifth phase. It can be found that the decoupling effect of the adjacent first phase and the second phase is the best, that is, the peak value of the magnetic flux of the decoupling yoke is the smallest. This is because the magnetic flux waveforms of the two adjacent phases are closest, the degree of cancellation of the magnetic flux decoupling is the largest, and the peak magnetic flux of the decoupling yoke is the smallest. At this time, the cross-sectional area of ​​the decoupling yoke can be made smaller. Therefore, the decoupling integrated phase sequence of the n-phase staggered parallel integrated inductor should be the first phase, the second phase, the third phase...the nth phase is the best from top to bottom.

[0137] Taking the duty cycle D<1 / n as an example, Fig.10 is the n-phase inductor terminal voltage, the n-phase inductor core magnetic flux, and the magnetic flux waveforms of the first decoupling yoke and the (n-1)th decoupling yoke. L1 、u L2 …u Ln are the voltages across the first phase, second phase, ... nth phase inductors, Φ1 is the magnetic flux of the upper common yoke and the left and right winding poles of the first phase, Φ2 is the magnetic flux of the left and right winding poles of the second phase, Φ n is the magnetic flux of the lower common yoke and the left and right winding poles of the nth phase, Φ j1is the magnetic flux of the first decoupling yoke, Φ j(n-1) is the magnetic flux of the (n-1)th decoupling yoke. Analysis Fig.10 It can be found that due to the canceling effect of the magnetic flux of the two adjacent phases at the decoupling yoke, the peak value of the magnetic flux of the decoupling yoke is smaller than that of the winding column. Therefore, the cross-sectional area of ​​the decoupling yoke on the YZ plane can be greatly reduced, thereby optimizing the volume of the integrated magnetic component.

[0138] Therefore, the maximum magnetic flux expression of (n-1) decoupling yokes can be obtained as follows:

[0139]

[0140] In some embodiments, the length of each phase winding post is determined according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding post, and the equivalent magnetic path length of the common yoke and the decoupling yoke, including:

[0141] The maximum DC bias current is determined according to the number of turns of the winding, the magnetic field strength in the winding column, the magnetic field strength in the common yoke and the decoupling yoke, the equivalent magnetic path length of the winding column, and the equivalent magnetic path length of the common yoke and the decoupling yoke. The maximum DC bias current is related to H1l eq1 +H2l eq2 =NI dc ;

[0142] Among them, H1 is the magnetic field strength in the winding column, H2 is the magnetic field strength in the common yoke and the decoupling yoke, l eq1 is the equivalent magnetic path length of the winding column, l eq2 is the equivalent magnetic path length of the common yoke and the decoupling yoke, I dc is the maximum DC bias current;

[0143] Determine the relationship between the maximum magnetic flux density of the winding column and the maximum magnetic flux density and magnetic permeability of the ordinary magnetic yoke and the decoupling magnetic yoke. The expression for the relationship between the magnetic flux density, magnetic permeability and magnetic field strength is:

[0144]

[0145] Among them, B m1 is the maximum magnetic flux density of the winding column, μ1 is the magnetic permeability of the winding column, B m2 is the maximum magnetic density of the common yoke and the decoupling yoke, μ2 is the magnetic permeability of the common yoke and the decoupling yoke;

[0146] Determine the magnetic resistance of the winding column based on the magnetic permeability;

[0147] The length of the winding post is determined based on the magnetic resistance of the winding post.

[0148] If the winding column uses ferrite, the inductance can be adjusted by adjusting the size of the air gap. The larger the air gap, the lower the inductance, and the smaller the air gap, the higher the inductance.

[0149] When the winding column uses a magnetic material with low magnetic permeability, such as a powder core, if the inductance of each phase needs to be adjusted, it is necessary to adjust the length of the powder core to change the magnetic resistance of the winding column and then adjust the inductance. Since the magnetic permeability of the powder core decreases as the bias DC current increases, it is necessary to meet the inductance requirements under the DC bias current. Suppose the function of the change of the magnetic permeability of the powder core with the magnetic field strength H1 on it is Where %u i : The ratio of the powder core magnetic permeability to the initial magnetic permeability, a, b, c are coefficients provided by the manufacturer. Assume that the magnetic field strength in the powder core winding column is H1, and the magnetic field strength in the ordinary yoke and the decoupled yoke is H2. According to the total current theorem, we can get: H1l eq1 +H2l eq2 =NI dc , where l eq1 is the equivalent magnetic path length of the winding column core, l eq2 is the equivalent magnetic path length of the common yoke and the decoupling yoke, N is the number of winding turns of each phase inductance, I dc is the maximum DC bias current. The relationship between the maximum magnetic flux density, magnetic permeability, and magnetic field strength of the two core materials is: Among them B m1 , μ1, H1 are the maximum magnetic density, magnetic permeability, and magnetic field intensity in the winding column, B m2 , μ2, H2 are the maximum magnetic density, magnetic permeability, and magnetic field strength of the ordinary yoke and the decoupling yoke. According to the above formula, the magnetic field strength in the winding post powder core can be calculated, so that the magnetic permeability of the winding post powder core under the maximum bias current can be obtained, and then the magnetic resistance of the winding post powder core can be calculated to determine the length of the winding post powder core. If the inductance of each phase is too small, it is necessary to reduce the equivalent magnetic resistance of the inductance of each phase, that is, it is necessary to reduce the length of the winding post, and adjust it repeatedly until the inductance of each phase meets the requirements under the maximum bias current.

[0150] Fig.11A schematic diagram of the structure of a size determination system of an integrated inductor provided by the present invention, wherein the magnetic core of the integrated inductor comprises an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding, wherein the winding post comprises a left winding post and a right winding post, wherein the first decoupling yoke to the n-1th decoupling yoke are sequentially arranged between the upper common yoke and the lower common yoke, wherein the upper part of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, and the lower part is connected to the i+1th phase left winding post and the i+1th phase right winding post, wherein the upper common yoke is respectively connected to the first phase left winding post and the first phase right winding post, wherein the lower common yoke is respectively connected to the n-th phase left winding post and the n-th phase right winding post, wherein N / 2 turns of winding are wound on the left winding post and the right winding post of each phase, wherein 1<i<n, and i and n are both integers, and the size determination system of the integrated inductor comprises:

[0151] An equivalent magnetic circuit determining unit 21, used to determine the equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor;

[0152] A magnetic flux determination unit 22, used to determine the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit;

[0153] A cross-sectional area determination unit 23, used to determine the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common yoke and the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux;

[0154] The length determination unit 24 is used to determine the length of each phase winding column according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding column, and the equivalent magnetic path length of the common yoke and the decoupling yoke;

[0155] The size determination unit 25 is used to determine the size of the integrated inductor according to the cross-sectional area of ​​the winding post, the cross-sectional area of ​​the common yoke, the cross-sectional area of ​​the decoupling yoke, and the length of each phase winding post.

[0156] Based on the above embodiments:

[0157] The equivalent magnetic circuit determination unit 21 is specifically used to determine the equivalent magnetic circuit of the inductor according to the winding rod magnetic resistance, magnetomotive force, ordinary magnetic yoke magnetic resistance and decoupled magnetic yoke magnetic resistance.

[0158] The equivalent magnetic circuit determination unit 21 is specifically used to determine the equivalent magnetic circuit of the inductor according to the winding column magnetic resistance, magnetomotive force, ordinary magnetic yoke magnetic resistance, decoupled magnetic yoke magnetic resistance and connection relationship;

[0159] The connection relationship includes the first end of the i-th decoupling yoke magnetic resistance being connected to the negative end of the i-th magnetomotive force and the first end of the i+1-th winding pole magnetic resistance, the positive end of the i-th magnetomotive force being connected to the first end of the i-th winding pole magnetic resistance, the second end of the i-th winding pole magnetic resistance being connected to the first end of the i-1-th decoupling yoke magnetic resistance, and the second end of the i-1-th decoupling yoke magnetic resistance being connected to the second end of the i-th decoupling yoke magnetic resistance; the first end of the first common yoke magnetic resistance being connected to the second end of the first winding pole magnetic resistance, the second end of the first common yoke magnetic resistance being connected to the second ends of each decoupling yoke magnetic resistance and the second end of the second common yoke magnetic resistance, and the first end of the second common yoke magnetic resistance being connected to the negative end of the n-th magnetomotive force, where i is an integer greater than 1.

[0160] The magnetic flux determination unit 22 is specifically used to determine the magnetic flux of each decoupling yoke as the magnetic flux of the corresponding phase. The relationship between the magnetic flux of each phase is:

[0161] Among them, Φ1(t) is the magnetic flux between the upper common yoke and the first phase winding column, Φ n (t) is the magnetic flux between the lower common yoke and the nth phase winding pole, Φ j1 (t) is the magnetic flux of the first decoupling yoke, Φ j(n-1) (t) is the magnetic flux of the n-1th decoupling yoke, i L1 (t) is the current flowing through the first phase winding, i Ln (t) is the current flowing through the n-th phase winding, and R is the magnetic resistance of the winding column.

[0162] It also includes a magnetic flux maximum value determining unit, which is used to determine the maximum value of the magnetic flux. The expression of the maximum value of the magnetic flux is:

[0163] Among them, Φ max is the maximum value of magnetic flux, Φ dc is the DC magnetic flux, △Φ is the AC magnetic flux;

[0164] Enter the step of determining the cross-sectional area of ​​the winding pole, the cross-sectional area of ​​the common yoke and the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux.

[0165] The process of determining DC flux includes:

[0166] The DC flux is determined based on the number of turns of the winding wound on each phase winding pole, the maximum DC bias current, the magnetic resistance of the upper common magnetic yoke, the magnetic resistance of the lower common magnetic yoke, the magnetic resistance of the decoupling magnetic yoke and the DC flux relationship. The DC flux relationship is:

[0167] Where R is the magnetic resistance of the winding column, R m is the magnetic resistance of each decoupling yoke, R m1is the magnetic resistance of the upper common yoke and the lower common yoke, I dc is the maximum DC bias current, and L1 is the self-inductance of the first phase.

[0168] The process of determining the self-inductance of the first phase includes:

[0169] The self-inductance of each phase is determined based on the reluctance of the winding column, the reluctance of each decoupling yoke, the reluctance of the upper common yoke and the lower common yoke. The expression of self-inductance is

[0170] Where L1 is the self-inductance of the first phase, L n is the self-inductance of the nth phase, R is the magnetic resistance of the winding column, R m is the magnetic resistance of each decoupling yoke, R m1 is the magnetic resistance of the upper common yoke and the lower common yoke.

[0171] The cross-sectional area determination unit 23 is specifically used to determine the cross-sectional area of ​​each phase winding post on the XY plane according to the maximum value of the magnetic flux and the maximum magnetic density of the winding post magnetic core material. The relationship between the cross-sectional area of ​​the winding post on the XY plane is:

[0172] Among them, Φ max is the maximum value of magnetic flux, B m1 is the maximum magnetic flux density of the winding core material, △Φ is the AC magnetic flux, L1 is the self-inductance of the first phase, I dc is the maximum DC bias current, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle.

[0173] The cross-sectional area of ​​each phase common yoke on the YZ plane is determined according to the maximum value of magnetic flux and the maximum magnetic density of the common yoke core material. The relationship between the cross-sectional area of ​​the common yoke on the YZ plane is:

[0174]

[0175] Among them, Φ max is the maximum value of magnetic flux, B m2 is the maximum magnetic density of the common yoke core material, △Φ is the AC magnetic flux, L1 is the self-inductance of the first phase, I dc is the maximum DC bias current, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle.

[0176] Determine the maximum magnetic flux of the decoupling yoke;

[0177] Determine the cross-sectional area of ​​the decoupling yoke on the YZ plane based on the maximum magnetic flux. The expression for the cross-sectional area is:

[0178]

[0179] Among them, Φ j1max is the maximum magnetic flux of the decoupling yoke, A ej1 To A ej(n-1) is the cross-sectional area of ​​the decoupling yoke on the YZ surface, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle, B m2 It is the maximum magnetic flux density of the decoupling yoke core material.

[0180] The length determination unit 24 is specifically used to determine the maximum DC bias current according to the number of turns of the winding, the magnetic field strength in the winding column, the magnetic field strength in the common yoke and the decoupling yoke, the equivalent magnetic path length of the winding column, and the equivalent magnetic path length of the common yoke and the decoupling yoke. The relationship between the maximum DC bias current and the maximum DC bias current is: eq1 +H2l eq2 =NI dc ;

[0181] Among them, H1 is the magnetic field strength in the winding column, H2 is the magnetic field strength in the common yoke and decoupling yoke, l eq1 is the equivalent magnetic path length of the winding column, l eq2 is the equivalent magnetic path length of the common yoke and the decoupling yoke, I dc is the maximum DC bias current;

[0182] Determine the relationship between the maximum magnetic flux density of the winding column and the maximum magnetic flux density and magnetic permeability of the ordinary magnetic yoke and the decoupling magnetic yoke. The expression of the relationship between the magnetic flux density, magnetic permeability and magnetic field strength is:

[0183]

[0184] Among them, B m1 is the maximum magnetic flux density of the winding column, μ1 is the magnetic permeability of the winding column, B m2 is the maximum magnetic density of the common yoke and the decoupling yoke, μ2 is the magnetic permeability of the common yoke and the decoupling yoke;

[0185] Determine the magnetic resistance of the winding column based on the magnetic permeability;

[0186] The length of the winding post is determined based on the magnetic resistance of the winding post.

[0187] Fig.12 A schematic diagram of the structure of a device for determining the size of an integrated inductor provided by the present invention, wherein the device for determining the size of an integrated inductor comprises:

[0188] A memory 31, used for storing computer programs;

[0189] The processor 32 is configured to implement the steps of the above-mentioned method for determining the size of the integrated inductor when executing the computer program.

[0190] For an introduction to the device for determining the size of an integrated inductor provided in the present application, please refer to the above embodiments, which will not be described in detail here.

[0191] Figure 2 A schematic diagram of the structure of an integrated inductor provided by the present invention, wherein the magnetic core of the integrated inductor comprises an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding, wherein the winding post comprises a left winding post and a right winding post, wherein the first decoupling yoke to the n-1th decoupling yoke are sequentially arranged between the upper common yoke and the lower common yoke, wherein the upper portion of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, and the lower portion is connected to the i+1-th phase left winding post and the i+1-th phase right winding post, wherein the upper common yoke is respectively connected to the first phase left winding post and the first phase right winding post, wherein the lower common yoke is respectively connected to the n-th phase left winding post and the n-th phase right winding post, wherein N / 2 turns of winding are wound on the left winding post and the right winding post of each phase, wherein 1<i<n, and i and n are both integers.

[0192] The embodiment of the present application discloses a design method of an n-phase high-decoupling integrated inductor, which is used to solve the problems of excessive cost, volume and weight of the inductor structure in the existing n-phase power converter. The magnetic core of the n-phase integrated inductor includes 2 ordinary yokes, (n-1) decoupling yokes, and 2n winding poles. The yoke part adopts a magnetic material with high magnetic permeability, such as ferrite. The winding pole part adopts a magnetic material with low magnetic permeability, such as a powder core.

[0193] Figure 2 A front view of an n-phase staggered parallel integrated inductor provided by the present invention, Figure 5 A top view of an n-phase staggered parallel integrated inductor provided by the present invention, Figure 6 A side view of an n-phase staggered parallel integrated inductor provided by the present invention;

[0194] The N turns of winding of each phase are wound on the left and right winding poles, and the number of turns on the left and right winding poles is N / 2.

[0195] Among them, air gaps may be left between the left and right winding posts of the first phase and the upper common yoke and the first decoupling yoke, air gaps may be left between the left and right winding posts of the second phase and the first decoupling yoke and the second decoupling yoke, and air gaps may be left between the left and right winding posts of the nth phase and the lower common yoke and the (n-1)th decoupling yoke. The first decoupling yoke is located between the first phase and the second phase winding posts. The second decoupling yoke is located between the second phase and the third phase winding posts. The (n-1)th decoupling yoke is located between the (n-1)th phase and the nth phase winding posts. The heights of the (n-1) decoupling yokes in the Z direction are all less than the heights of the two common yokes in the Z direction. The depths of the two common yokes and the (n-1) decoupling yokes in the Y direction are greater than the depths of all winding posts in the Y direction. The core cross-sectional area of ​​the winding post on the XY plane is less than the core cross-sectional area of ​​the two common yokes on the YZ plane.

[0196] For an introduction to the integrated inductor provided in this application, please refer to the above embodiments, which will not be described in detail here.

[0197] The present invention also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the method for determining the size of an integrated inductor according to any one of claims 1 to 11 are implemented.

[0198] For an introduction to the computer-readable storage medium provided in this application, please refer to the above embodiments and will not be repeated here.

[0199] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0200] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0201] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0202] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0203] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for determining the size of an integrated inductor, characterized in that: The magnetic core of the integrated inductor includes an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding, wherein the winding post includes a left winding post and a right winding post, and the first decoupling yoke to the n-1th decoupling yoke are sequentially arranged between the upper common yoke and the lower common yoke, the upper part of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, and the lower part is connected to the i+1th phase left winding post and the i+1th phase right winding post, the upper common yoke is respectively connected to the first phase left winding post and the first phase right winding post, the lower common yoke is respectively connected to the n-th phase left winding post and the n-th phase right winding post, and N / 2 turns of winding are wound on the left winding post and the right winding post of each phase, 1<i<n, i and n are both integers, and N is an even number; The method for determining the size of the integrated inductor comprises: Determining an equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor; determining the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit; Determining the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common magnetic yoke, and the cross-sectional area of ​​the decoupling magnetic yoke according to the maximum value of the magnetic flux; Determine the length of each phase winding post according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding post, and the equivalent magnetic path lengths of the common yoke and the decoupling yoke; The size of the integrated inductor is determined according to the cross-sectional area of ​​the winding post, the cross-sectional area of ​​the common yoke, the cross-sectional area of ​​the decoupling yoke, and the length of each phase winding post.

2. The method for determining the size of an integrated inductor according to claim 1, wherein: Determining an equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor includes: The magnetomotive force, winding rod reluctance, common yoke reluctance and decoupled yoke reluctance in the equivalent magnetic circuit of the magnetic core are determined according to the structure of the magnetic core of the integrated inductor.

3. The method for determining the size of an integrated inductor according to claim 2, characterized in that: According to the structure of the magnetic core of the integrated inductor, the magnetomotive force, the winding column magnetic resistance, the common magnetic yoke magnetic resistance and the decoupled magnetic yoke magnetic resistance in the equivalent magnetic circuit of the magnetic core are determined, including: Determine the connection relationship between the magnetomotive force, winding rod magnetic resistance, common magnetic yoke magnetic resistance and decoupling magnetic yoke magnetic resistance in the equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor; The connection relationship includes the first end of the i-th decoupling yoke magnetic resistance being connected to the negative end of the i-th magnetomotive force and the first end of the i+1-th winding pole magnetic resistance, the positive end of the i-th magnetomotive force being connected to the first end of the i-th winding pole magnetic resistance, the second end of the i-th winding pole magnetic resistance being connected to the first end of the i-1-th decoupling yoke magnetic resistance, and the second end of the i-1-th decoupling yoke magnetic resistance being connected to the second end of the i-th decoupling yoke magnetic resistance; the first end of the first common yoke magnetic resistance being connected to the second end of the first winding pole magnetic resistance, the second end of the first common yoke magnetic resistance being connected to the second end of each of the decoupling yoke magnetic resistances and the second end of the second common yoke magnetic resistance, and the first end of the second common yoke magnetic resistance being connected to the negative end of the n-th magnetomotive force, where i is an integer greater than 1.

4. The method for determining the size of an integrated inductor according to claim 1, wherein: Determining the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit includes: Determine the magnetic flux of each decoupling yoke, the relationship between the magnetic flux of each phase is Among them, Φ1(t) is the magnetic flux between the upper common yoke and the first phase winding column, Φ n (t) is the magnetic flux between the lower common yoke and the nth phase winding pole, Φ j1 (t) is the magnetic flux of the first decoupling yoke, Φ j(n-1) (t) is the magnetic flux of the n-1th decoupling yoke, i L1 (t) is the current flowing through the first phase winding, i Ln (t) is the current flowing through the n-th phase winding, and R is the magnetic resistance of the winding column.

5. The method for determining the size of an integrated inductor according to claim 1, wherein: Before determining the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common magnetic yoke and the cross-sectional area of ​​the decoupling magnetic yoke according to the maximum value of the magnetic flux, the method further includes: Determine the maximum value of the magnetic flux, the expression of the maximum value of the magnetic flux is: Among them, Φ max is the maximum value of the magnetic flux, Φ dc is the DC magnetic flux, △Φ is the AC magnetic flux; The step of further determining the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common yoke and the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux.

6. The method for determining the size of an integrated inductor according to claim 5, characterized in that: The process of determining the DC magnetic flux includes: The DC magnetic flux is determined according to the number of turns of the winding wound on each phase winding pole, the maximum DC bias current, the magnetic resistance of the upper common magnetic yoke, the magnetic resistance of the lower common magnetic yoke, and the magnetic resistance of the decoupling magnetic yoke. The DC magnetic flux relationship is: Where R is the magnetic resistance of the winding column, R m is the magnetic resistance of each decoupling yoke, R m1 is the magnetic resistance of the upper common yoke and the lower common yoke, I dc is the maximum DC bias current, and L1 is the self-inductance of the first phase inductor.

7. The method for determining the size of an integrated inductor according to claim 6, wherein: The process of determining the self-inductance of the first phase inductor includes: The self-inductance of each phase is determined according to the magnetic resistance of the winding column, the magnetic resistance of each decoupling yoke, the magnetic resistance of the upper common yoke and the magnetic resistance of the lower common yoke. The expression of the self-inductance is: Where L1 is the self-inductance of the first phase inductor, L n is the self-inductance of the first phase inductor, R is the magnetic resistance of the winding column, R m is the magnetic resistance of each decoupling yoke, R m1 is the magnetic resistance of the upper common yoke and the lower common yoke.

8. The method for determining the size of an integrated inductor according to claim 1, wherein: Determining the cross-sectional area of ​​the winding column according to the maximum value of the magnetic flux includes: The cross-sectional area of ​​each phase of the winding post on the XY plane is determined according to the maximum value of the magnetic flux and the maximum magnetic density of the winding post magnetic core material. The relationship between the cross-sectional area of ​​the winding post on the XY plane is: Among them, Φ max is the maximum value of the magnetic flux, B m1 is the maximum magnetic density of the winding core material, △Φ is the AC magnetic flux, L1 is the self-inductance of the first phase inductor, I dc is the maximum DC bias current, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching period, Φ dc is the DC magnetic flux, A e1 is the cross-sectional area of ​​the winding column on the XY plane.

9. The method for determining the size of an integrated inductor according to claim 1, wherein: Determining the cross-sectional area of ​​the common magnetic yoke according to the maximum value of the magnetic flux comprises: The cross-sectional area of ​​the common yoke on the YZ plane of each phase is determined according to the maximum value of the magnetic flux and the maximum magnetic density of the common yoke core material. The relationship formula of the cross-sectional area of ​​the common yoke on the YZ plane is: Among them, Φ max is the maximum value of the magnetic flux, B m2 is the maximum magnetic density of the common yoke core material, △Φ is the AC magnetic flux, L1 is the self-inductance of the first phase inductor, I dc is the maximum DC bias current, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle.

10. The method for determining the size of an integrated inductor according to claim 1, wherein: Determining the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux comprises: determining a maximum magnetic flux of the decoupling yoke; The cross-sectional area of ​​the decoupling yoke on the YZ plane is determined according to the maximum magnetic flux, and the expression of the cross-sectional area is: Among them, Φ j1max is the maximum magnetic flux of the decoupling yoke, A ej1 To A ej(n-1) is the cross-sectional area of ​​the decoupling yoke on the YZ surface, V i is the input voltage of the integrated inductor, V o is the output voltage of the integrated inductor, D is the duty cycle, T s is the switching cycle, B m2 It is the maximum magnetic flux density of the decoupling yoke core material.

11. The method for determining the size of an integrated inductor according to any one of claims 1 to 10, characterized in that: The length of each phase winding post is determined according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding post, and the equivalent magnetic path lengths of the common magnetic yoke and the decoupling magnetic yoke, including: The maximum DC bias current is determined according to the number of turns of the winding, the magnetic field strength in the winding column, the magnetic field strength in the common yoke and the decoupling yoke, the equivalent magnetic path length of the winding column, and the equivalent magnetic path length of the common yoke and the decoupling yoke. The relationship of the maximum DC bias current is H1l eq1 +H2l eq2 =NI dc ; Wherein, H1 is the magnetic field strength in the winding column, H2 is the magnetic field strength in the common magnetic yoke and the decoupling magnetic yoke, l eq1 is the equivalent magnetic path length of the winding column, l eq2 is the equivalent magnetic path length of the common yoke and the decoupling yoke, I dc is the maximum DC bias current; Determine the relationship between the maximum magnetic flux density of the winding column and the maximum magnetic flux density and magnetic permeability of the common magnetic yoke and the decoupling magnetic yoke. The expression of the relationship between the magnetic flux density, magnetic permeability and magnetic field strength is: Among them, B m1 is the maximum magnetic flux density of the winding column, μ1 is the magnetic permeability of the winding column, B m2 is the maximum magnetic density of the common yoke and the decoupling yoke, μ2 is the magnetic permeability of the common yoke and the decoupling yoke; determining the magnetic resistance of the winding post according to the magnetic permeability; The length of the winding post is determined according to the magnetic resistance of the winding post.

12. A system for determining the size of an integrated inductor, characterized in that: The magnetic core of the integrated inductor includes an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding, wherein the winding post includes a left winding post and a right winding post, and the first decoupling yoke to the n-1th decoupling yoke are sequentially arranged between the upper common yoke and the lower common yoke, the upper part of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, and the lower part is connected to the i+1th phase left winding post and the i+1th phase right winding post, the upper common yoke is respectively connected to the first phase left winding post and the first phase right winding post, the lower common yoke is respectively connected to the n-th phase left winding post and the n-th phase right winding post, each phase left winding post and the right winding post are wound with N / 2 turns of winding, 1<i<n, i and n are both integers, and the size determination system of the integrated inductor includes: An equivalent magnetic circuit determining unit, configured to determine an equivalent magnetic circuit of the magnetic core according to the structure of the magnetic core of the integrated inductor; a magnetic flux determination unit, configured to determine the magnetic flux of each phase in the magnetic core according to the equivalent magnetic circuit; A cross-sectional area determination unit, configured to determine the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common yoke, and the cross-sectional area of ​​the decoupling yoke according to the maximum value of the magnetic flux; A length determination unit, configured to determine the length of each phase winding post according to the number of turns of the winding, the maximum DC bias current of the integrated inductor, the equivalent magnetic path length of the winding post, and the equivalent magnetic path lengths of the common yoke and the decoupling yoke; The size determination unit is used to determine the size of the integrated inductor according to the cross-sectional area of ​​the winding column, the cross-sectional area of ​​the common yoke, the cross-sectional area of ​​the decoupling yoke and the length of each phase winding column.

13. A device for determining the size of an integrated inductor, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the method for determining the size of an integrated inductor according to any one of claims 1 to 11 when executing the computer program.

14. An integrated inductor, characterized in that: The magnetic core of the integrated inductor includes an upper common yoke, a lower common yoke, a decoupling yoke, a winding post and a winding, wherein the winding post includes a left winding post and a right winding post, and the first decoupling yoke to the n-1th decoupling yoke are sequentially arranged between the upper common yoke and the lower common yoke, the upper part of the i-th decoupling yoke is connected to the i-th phase left winding post and the i-th phase right winding post, and the lower part is connected to the i+1-th phase left winding post and the i+1-th phase right winding post, the upper common yoke is respectively connected to the first phase left winding post and the first phase right winding post, the lower common yoke is respectively connected to the n-th phase left winding post and the n-th phase right winding post, and N / 2 turns of winding are wound on the left winding post and the right winding post of each phase, 1<i<n, i and n are both integers.

15. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for determining the size of an integrated inductor according to any one of claims 1 to 11 are implemented.

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