System and method for measuring power loss of magnetic element

Abstract

The invention relates to the field of power electronics, in particular to a system and a method for measuring power loss of a magnetic element. The system comprises a power measuring unit, a power circuit and a to-be-measured magnetic element which are sequentially connected in series, and further comprises at least two auxiliary magnetic elements which are connected with the to-be-measured magnetic element in parallel, and the auxiliary magnetic elements and the to-be-measured magnetic element are the same in structure; and the control unit is connected with the at least two auxiliary magnetic elements and the power measurement unit, and is used for obtaining the power difference of the at least two auxiliary magnetic elements measured by the power measurement unit before and after the sequential access so as to obtain the power loss representing the magnetic element to be measured. According to the application, the auxiliary magnetic element with the same magnetic core loss as the magnetic element to be measured is constructed, the other loss, except the magnetic core loss, introduced by the auxiliary magnetic element can be neglected, and the power difference of the at least two auxiliary magnetic elements measured by the power measurement unit before and after the connection in sequence is acquired, so that the power loss representing the magnetic element to be measured is obtained.

Description

Technical Field

[0001] The present application relates to the field of power electronics, and particularly to a power loss measurement system and method for a magnetic component. Background Art

[0002] When integrating and optimizing the design of magnetic components, accurate evaluation of the power loss of magnetic components is crucial.

[0003] In the prior art, by building a standard circuit platform and applying a power signal excitation to the magnetic component, such as building a bridge inverter circuit for testing. The disadvantages of this solution are that on the one hand, building a standard excitation source circuit and a test platform is relatively complex and costly; on the other hand, the built test circuit can generally only output standard waveforms such as square waves and triangular waves, and it is difficult to output arbitrary excitation waveforms, resulting in test deviations; thirdly, the built test platform cannot measure complex magnetic component systems, such as integrated magnetic component systems. Summary of the Invention

[0004] Based on this, it is necessary to provide a power loss measurement system and method for a magnetic component in view of the above technical problems.

[0005] In a first aspect, an embodiment of the present application provides a power loss measurement system for a magnetic component. The system includes a power measurement unit, a power circuit, and a magnetic component to be measured connected in series in sequence. The system further includes:

[0006] At least two auxiliary magnetic components connected in parallel with the magnetic component to be measured, and the auxiliary magnetic components have the same structure as the magnetic component to be measured;

[0007] And a control unit connected to the at least two auxiliary magnetic components and the power measurement unit, configured to obtain the power differences before and after each of the at least two auxiliary magnetic components are connected in sequence as measured by the power measurement unit, so as to obtain the power loss characterizing the magnetic component to be measured.

[0008] In some embodiments, the control unit controls the connection of the next auxiliary magnetic component on the basis of controlling the connection of the previous auxiliary magnetic component.

[0009] In some embodiments, the control unit disconnects the connection of the previous auxiliary magnetic component before controlling the connection of the next auxiliary magnetic component.

[0010] In some embodiments, the control unit obtains the average value of the power differences before and after the connection of the corresponding auxiliary magnetic component, so as to obtain the power loss characterizing the magnetic component to be measured.

[0011] In some embodiments, the auxiliary magnetic element has the same number of winding turns and winding method as the magnetic element to be measured, and the magnetic cores of the auxiliary magnetic element and the magnetic element to be measured have the same shape, size and material.

[0012] In some embodiments, the ratio of the resistive impedance of the magnetic element to be measured to that of the auxiliary magnetic element is The ratio of the inductive impedance is N represents the number of the auxiliary magnetic elements, and the constant K is much greater than 1.

[0013] In some embodiments, the system further includes:

[0014] At least two switching elements connected to each of the auxiliary magnetic elements and the control unit;

[0015] The control unit controls the at least two switching elements to control the access of the corresponding auxiliary magnetic element.

[0016] In a second aspect, an embodiment of the present application provides a method for measuring the power loss of a magnetic element, which is used for the system as described in the first aspect. The method includes:

[0017] Obtain the power differences before and after controlling the sequential access of at least two auxiliary magnetic elements;

[0018] Based on each of the power differences, obtain the power loss characterizing the magnetic element to be measured.

[0019] In some embodiments, the controlling the sequential access of at least two auxiliary magnetic elements includes:

[0020] On the basis of controlling the access of the previous auxiliary magnetic element, control the access of the next auxiliary magnetic element.

[0021] In some embodiments, the controlling the sequential access of at least two auxiliary magnetic elements includes:

[0022] Before controlling the access of the next auxiliary magnetic element, disconnect the access of the previous auxiliary magnetic element.

[0023] Compared with the prior art, the present application constructs an auxiliary magnetic component with the same core loss as the magnetic component to be measured, and the other losses introduced by the auxiliary magnetic component except for the core loss can be ignored. By obtaining the power differences before and after at least two auxiliary magnetic components are successively connected as measured by the power measurement unit, the power loss of the magnetic component to be measured is obtained. Therefore, the present application does not need to build a standard excitation source circuit and a test platform, and the measurement cost is low; the excitation of the magnetic component to be measured is completely consistent with the actual working condition, realizing "in-situ measurement" and increasing the measurement accuracy; it is applicable to measuring complex magnetic component systems and solves the technical problem that it is difficult to measure power loss; it does not require high-precision test equipment such as high-precision oscilloscopes, and the test result can be obtained by using a conventional power meter to measure the power and then performing calculations. The measurement is simple and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the structure of the original working platform for the magnetic component to be measured;

[0025] Figure 2 Schematic diagram of the structure of the power loss measurement system of the magnetic component in an embodiment of the present application;

[0026] Figure 3 Schematic diagram of the structure of the power loss measurement system of the magnetic component in an exemplary embodiment of the present application;

[0027] Figure 4 Schematic diagram of the structure of the power loss measurement system of the magnetic component in another exemplary embodiment of the present application;

[0028] Figure 5 Schematic diagram of the flow of the power loss measurement method of the magnetic component in an exemplary embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some examples or embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, the present invention can also be applied to other similar scenarios based on these drawings. Unless obvious from the language context or otherwise stated, the same reference numerals in the drawings represent the same structure or operation.

[0030] As shown in the present invention and the claims, unless the context clearly indicates an exception, words such as "a", "an", "one" and / or "the" are not specifically singular and may also include plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0031] Although the present invention makes various references to certain modules in the system according to embodiments of the present invention, any number of different modules can be used and run on a computing device and / or a processor. The modules are merely illustrative, and different aspects of the system and method can use different modules.

[0032] It should be understood that when a unit or module is described as "connected" or "coupled" to other units, modules, or blocks, it may mean a direct connection or coupling, or communicate with other units, modules, or blocks, or there may be intermediate units, modules, or blocks, unless the context clearly indicates otherwise. The term "and / or" as used herein may include any and all combinations of one or more of the related listed items.

[0033] The original working platform of the magnetic element to be measured is as Figure 1 shown. The magnetic element to be measured is connected to the output end of the power circuit, and the input end of the power circuit is connected to a power supply.

[0034] Wherein, the power circuit is a circuit system in the original working platform of the magnetic element to be measured, and is used to output power to provide excitation for the magnetic element to be measured.

[0035] Wherein, the magnetic element to be measured is, for example, a transformer, an integrated magnetic element system, etc.

[0036] In the prior art, by building a standard circuit platform, a power signal excitation is applied to the magnetic element, such as building a bridge inverter circuit for testing. The disadvantages of this solution are that on the one hand, building a standard excitation source circuit and a test platform is relatively complex and costly; second, the built test circuit generally can only output standard waveforms such as square waves and triangular waves, and it is difficult to output arbitrary excitation waveforms, resulting in test deviations; third, the built test platform cannot measure complex magnetic element systems, such as integrated magnetic element systems.

[0037] To solve the above technical problems, an embodiment of the present application proposes a power loss measurement system for a magnetic element, as Figure 2 shown. The system includes a power measurement unit, a power circuit, and a magnetic element to be measured that are connected in series in sequence. The system further includes: at least two auxiliary magnetic elements connected in parallel with the magnetic element to be measured, and the auxiliary magnetic elements have the same structure as the magnetic element to be measured; and a control unit (not shown in the figure) connected to the at least two auxiliary magnetic elements and the power measurement unit, and is used to obtain the power differences before and after the at least two auxiliary magnetic elements are connected in sequence measured by the power measurement unit, so as to obtain the power loss characterizing the magnetic element to be measured.

[0038] Among them, the power measurement unit is, for example, a power meter, etc., which is used to measure the input power of the power circuit, that is, the total power of the power circuit and the magnetic component under test and the auxiliary magnetic component connected thereto.

[0039] In this embodiment, an auxiliary magnetic component with the same core loss as the magnetic component under test is constructed, and the other losses introduced by the auxiliary magnetic component except for the core loss can be ignored. By obtaining the power differences before and after at least two auxiliary magnetic components are connected in sequence measured by the power measurement unit, the power loss of the magnetic component under test is obtained. Therefore, this embodiment does not require building a standard excitation source circuit and a test platform, and the measurement cost is low; the excitation of the magnetic component under test is completely consistent with the actual working conditions, realizing "in-situ measurement" and increasing the measurement accuracy; it is applicable to measuring complex magnetic component systems and solves the technical problem of difficult measurement of power loss; it does not require high-precision test equipment such as high-precision oscilloscopes, and the test result can be obtained by using a conventional power meter to measure the power and then calculating. The measurement is simple and the cost is low.

[0040] The power loss measurement system proposed in this application can control the connection of the auxiliary magnetic component through two connection methods.

[0041] In one implementation, the control unit controls the connection of the next auxiliary magnetic component on the basis of controlling the connection of the previous auxiliary magnetic component.

[0042] In another implementation, the control unit disconnects the connection of the previous auxiliary magnetic component before controlling the connection of the next auxiliary magnetic component.

[0043] Both of the above two control connection methods can measure and obtain the power loss characterizing the magnetic component under test.

[0044] In some embodiments, the control unit obtains the average value of the power differences before and after the corresponding auxiliary magnetic component is connected to obtain the power loss characterizing the magnetic component under test.

[0045] In order to ensure that the power loss of the added auxiliary magnetic component is the same as that of the magnetic component under test, first, the coil and core structures of the auxiliary magnetic component are designed to be the same, that is, the equivalent circuit of the auxiliary magnetic component is proportional to all impedance parameters of the magnetic component under test; second, the auxiliary magnetic component and the winding end points of the magnetic component under test are connected in parallel to the circuit, so as to ensure that the voltage excitations received are the same.

[0046] At this time, when the corresponding ends of the auxiliary magnetic element are connected in parallel to the circuit, the auxiliary magnetic element and the magnetic element to be measured will be subjected to the same voltage excitation. Also, because their structures are exactly the same, the excitation received by each magnetic path in the auxiliary magnetic element is also the same. Therefore, the power loss of the auxiliary magnetic element is exactly the same as that of the magnetic element to be measured. Thus, the calculated power loss of the auxiliary magnetic element is used to characterize the power loss of the magnetic element to be measured.

[0047] Specifically, the auxiliary magnetic element and the magnetic element to be measured have the same number of winding turns and winding method, and the magnetic cores of the auxiliary magnetic element and the magnetic element to be measured have the same shape, size, and material.

[0048] To ensure that the external loss introduced when the auxiliary magnetic element is incorporated into the circuit can be ignored, it is necessary to make the impedance of the auxiliary magnetic element as large as possible. Here, it is recommended that the impedance of the auxiliary magnetic element be more than 10 times the inductance of the magnetic element to be measured.

[0049] For example: as Figure 3 shown, taking the resistive impedance as an example, the ratio is Taking the inductive impedance as an example, the ratio is N represents the number of the auxiliary magnetic elements, and K represents a constant. The constant K is much larger than 1.

[0050] In some embodiments, the system further includes: at least two switching elements connected to each of the auxiliary magnetic elements and the control unit; the control unit controls the at least two switching elements to control the access of the corresponding auxiliary magnetic element.

[0051] The number of the switching elements is the same as the number of ports of the magnetic element to be measured. This technical solution is applicable to the measurement of the power loss of the magnetic element to be measured with two or more ports, and is applicable to both two-port single magnetic elements and multi-port integrated magnetic elements.

[0052] Exemplarily, when the magnetic element to be measured is only a single transformer, the transformer has three ports. As Figure 3 shown, by closing the switches S11, S12, and S13, the auxiliary magnetic element can be accessed.

[0053] In an exemplary embodiment, as Figure 4 shown, the power loss measurement system includes a first auxiliary magnetic element and a second auxiliary magnetic element. The first auxiliary magnetic element is connected in parallel with the magnetic element to be measured through the switching elements S11 and S12, and the second auxiliary magnetic element is connected in parallel with the magnetic element to be measured through the switching elements S21 and S22.

[0054] For this power loss measurement system, two power loss measurement methods can be adopted.

[0055] The first power loss measurement method includes the following steps:

[0056] Step 1: Turn off switches S11, S12, S21, and S22, and read the power measurement unit as P0.

[0057] Step 2: Turn on switches S11 and S12 to connect the first auxiliary magnetic element, and read the power measurement unit under the same working conditions as the previous step, denoted as P1; calculate the power loss difference between the two measurements as ΔP1 = P1 - P0.

[0058] Step 3: Turn on switches S21 and S22 to connect the second auxiliary magnetic element, and read the power measurement unit under the same working conditions as the previous step, denoted as P2; calculate the power loss difference between the two measurements as ΔP2 = P2 - P1.

[0059] Step 4: Calculate the power loss of the magnetic element to be measured as Pcore = 1 / 2 * (ΔP1 + ΔP2).

[0060] To further improve the test accuracy, the number of parallel auxiliary magnetic elements can be expanded to N (N≥2). At this time, the power loss after the Nth-level auxiliary magnetic element is connected is ΔP N = P N - P N-1 , and the power loss of the magnetic element to be measured is where x represents the number of measurements.

[0061] The second power loss measurement method includes the following steps:

[0062] Step 1: Turn off switches S11, S12, S21, and S22, and read the power measurement unit as P0';

[0063] Step 2: Turn on switches S11 and S12 to connect the first auxiliary magnetic element, and read the power measurement unit under the same working conditions as the previous step, denoted as P1'; calculate the power loss difference between the two measurements as ΔP1' = P1' - P0'.

[0064] Step 3: Turn off switches S11 and S12, turn on switches S21 and S22 to connect the second auxiliary magnetic element, and read the power measurement unit under the same working conditions as the previous step, denoted as P2'; calculate the power loss difference between the two measurements as ΔP2' = P2' - P0'.

[0065] Step 4: Calculate the power loss of the magnetic element to be measured as Pcore' = 1 / 2 * (ΔP1' + ΔP2').

[0066] As Figure 5 shown, the embodiment of the present application provides a method for measuring the power loss of a magnetic element for the system described in the first aspect, specifically including the following steps:

[0067] S202: Obtain the power differences before and after at least two auxiliary magnetic elements are successively connected;

[0068] S204: Based on each of the power differences, obtain the power loss characterizing the magnetic element to be measured.

[0069] Based on the above steps S202 - S204, in this embodiment, an auxiliary magnetic element with the same core loss as the magnetic element to be measured is constructed, and the remaining losses introduced by this auxiliary magnetic element except for the core loss can be ignored. By obtaining the power differences before and after at least two auxiliary magnetic elements are successively connected measured by the power measurement unit, the power loss characterizing the magnetic element to be measured is obtained. Therefore, this application does not require building a standard excitation source circuit and a test platform, and the measurement cost is low; the excitation of the magnetic element under test is completely consistent with the actual working conditions, realizing "in-situ measurement" and increasing the measurement accuracy; it is applicable to measuring complex magnetic element systems and solves the technical problem of difficult power loss measurement.

[0070] In some embodiments, the control of at least two auxiliary magnetic elements being successively connected includes:

[0071] On the basis of controlling the previous auxiliary magnetic element to be connected, then control the next auxiliary magnetic element to be connected.

[0072] In some embodiments, the control of at least two auxiliary magnetic elements being successively connected includes:

[0073] Before controlling the next auxiliary magnetic element to be connected, disconnect the connection of the previous auxiliary magnetic element.

[0074] In some embodiments, the control unit obtains the average value of the power differences before and after the corresponding auxiliary magnetic element is connected to obtain the power loss characterizing the magnetic element to be measured.

[0075] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps corresponding to the power loss measurement method in the above embodiments are implemented.

[0076] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc. The databases involved in the embodiments provided in this application can include at least one of relational databases and non-relational databases. Non-relational databases can include distributed databases based on blockchain, etc., without limitation. The processors involved in the embodiments provided in this application can be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, data processing logics based on quantum computing, artificial intelligence (AI) processors, etc., without limitation.

[0077] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0078] The above embodiments merely represent several implementation manners of the present application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all fall within the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A power loss measurement system for a magnetic component, the system comprising a power measurement unit, a power circuit, and a magnetic component to be measured that are connected in series in sequence, characterized in that, The system further includes: At least two auxiliary magnetic components connected in parallel with the magnetic component to be measured, the auxiliary magnetic components having the same structure as the magnetic component to be measured; and A control unit connected to the at least two auxiliary magnetic components and the power measurement unit, configured to obtain the power differences before and after the sequential connection of the at least two auxiliary magnetic components measured by the power measurement unit, so as to obtain the power loss characterizing the magnetic component to be measured.

2. The system according to claim 1, wherein Based on the connection of the previous auxiliary magnetic component controlled by the control unit, the control unit then controls the connection of the next auxiliary magnetic component.

3. The system according to claim 1, characterized in that, Before controlling the connection of the next auxiliary magnetic component, the control unit disconnects the connection of the previous auxiliary magnetic component.

4. The system according to claim 2 or 3, characterized in that, The control unit obtains the average value of the power differences before and after the connection of the corresponding auxiliary magnetic component, so as to obtain the power loss characterizing the magnetic component to be measured.

5. The system according to claim 1, wherein The auxiliary magnetic component and the magnetic component to be measured have the same number of winding turns and winding method, and the magnetic cores of the auxiliary magnetic component and the magnetic component to be measured have the same shape, size and material.

6. The system according to claim 1, wherein The ratio of the resistive impedance of the magnetic component to be measured to that of the auxiliary magnetic component is The ratio of the inductive impedance is N represents the number of the auxiliary magnetic components, and the constant K is much greater than 1.

7. The system according to claim 1, wherein The system further includes: At least two switching elements connected to each of the auxiliary magnetic components and the control unit; The control unit controls the at least two switching elements to control the connection of the corresponding auxiliary magnetic component.

8. A method for measuring the power loss of a magnetic component, for use in the system according to any one of claims 1-7, characterized in that, The method includes: Obtaining the power differences before and after the sequential connection of at least two auxiliary magnetic components; Based on the power differences, obtaining the power loss characterizing the magnetic component to be measured.

9. The method according to claim 8, characterized in that The sequential connection of the at least two auxiliary magnetic components includes: Based on the connection of the previous auxiliary magnetic component controlled, then controlling the connection of the next auxiliary magnetic component.

10. The method according to claim 8, wherein The sequential connection of the at least two auxiliary magnetic components includes: Before controlling the connection of the next auxiliary magnetic component, disconnecting the connection of the previous auxiliary magnetic component.

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