Magnetic element loss measuring method and related assembly

Abstract

The invention discloses a magnetic element loss measurement method and a related assembly, and relates to the technical field of power electronic magnetism, and the method comprises the steps: controlling a heater to heat a magnetic element to a preset temperature; determining the temperature difference between the magnetic element and a soaking block arranged on the surface of the magnetic element; controlling the excitation source to excite the magnetic element; controlling the power of the heater to be reduced so as to keep the temperature difference unchanged; a reduced power of the heater is determined, the reduced power of the heater being equal to the loss power of the magnetic element. When the excitation source excites the magnetic element, the loss of the magnetic element is dissipated in the form of heat, the temperature difference between the magnetic element and the soaking block is increased by heating the magnetic element, the power of the heater is controlled to be reduced at the moment, and the reduced power of the heater is equal to the power of the magnetic element under the condition that the temperature difference is constant, so that the loss power of the magnetic element can be determined. Electrical characteristics of the magnetic element do not need to be considered, heat generated by the magnetic element is used for measuring loss, and the obtained result is more accurate.

Description

Technical Field

[0001] The invention relates to the field of power electronic magnetic technology, and in particular to a method for measuring magnetic element loss and related components. Background Art

[0002] Magnetic component losses include winding losses and core losses. Winding losses are linear and can be simulated using finite element simulation software. However, there are many factors that affect core loss, and its accurate quantification has always been a difficult and hot topic in the industry. The AC method has a large error in measuring the core loss of magnetic components with an impedance angle close to 90°, and it is also difficult to accurately measure integrated magnetic components with complex magnetic flux distribution. Therefore, the loss measurement of magnetic components is an urgent problem to be solved by technicians in this field. Summary of the invention

[0003] The purpose of the present invention is to provide a method for measuring the loss of a magnetic element and related components, which do not need to consider the electrical characteristics of the magnetic element, and use the heat generated by the magnetic element to measure its loss, so that the result obtained is more accurate.

[0004] In order to solve the above technical problems, the present invention provides a method for measuring the loss of a magnetic component, comprising:

[0005] Controlling the heater to heat the magnetic element to a preset temperature;

[0006] Determining a temperature difference between the magnetic element and a heat spreader disposed on a surface of the magnetic element;

[0007] Controlling an excitation source to excite the magnetic element;

[0008] Controlling the power of the heater to decrease so as to keep the temperature difference constant;

[0009] A reduced power of the heater is determined, the reduced power of the heater being equal to the power loss of the magnetic element.

[0010] In another aspect, determining a temperature difference between the magnetic element and a heat-saturating block disposed on a surface of the magnetic element comprises:

[0011] When the heater is controlled to heat the magnetic element to a preset temperature, the temperature difference relationship is determined according to the power and specific heat capacity coefficient of the heater. The temperature difference relationship is: ;

[0012] When the excitation source is controlled to excite the magnetic element, the temperature difference relationship is determined according to the power and specific heat capacity coefficient of the heater. The temperature difference relationship is: ;

[0013] Among them, P 1is the power of the heater in the process of heating the magnetic element to a preset temperature, k is the specific heat capacity coefficient, ΔT is the temperature difference, P 磁元件 is the power loss of the magnetic component, P 2 is the power of the heater after the power of the heater is reduced.

[0014] On the other hand, a heat sink is further provided on a side of the heat equalizing block away from the magnetic element, and determining the reduced power of the heater includes:

[0015] Constructing an equivalent heat transfer model among the magnetic element, the heater, the heat equalizing block and the heat sink;

[0016] The reduced power of the heater is determined based on the equivalent heat transfer model.

[0017] On the other hand, an equivalent heat transfer model between the magnetic element, the heater, the heat equalization block and the heat sink is constructed, including:

[0018] The heat generation power of the magnetic element is equivalent to the first power, and the power of the heater is equivalent to the second power;

[0019] The specific heat capacity of the magnetic element is equivalent to the first heat capacity, the specific heat capacity of the heater is equivalent to the second heat capacity, and the specific heat capacity of the heat equalizing block is equivalent to the third heat capacity;

[0020] The temperature of the magnetic element is equivalent to the first node, the temperature of the heater is equivalent to the second node, the temperature of the heat block is equivalent to the third node, and the temperature of the heat sink is equivalent to the fourth node;

[0021] The thermal resistance between the magnetic element and the heater is equivalent to a first thermal resistance, the thermal resistance between the heater and the heat equalizing block is equivalent to a second thermal resistance, and the thermal resistance between the heat sink and the heat equalizing block is equivalent to a third thermal resistance;

[0022] An equivalent heat transfer model between the magnetic element, the heater, the heat equalizing block and the heat sink is constructed according to the first power, the second power, the first heat capacitance, the second heat capacitance, the third heat capacitance, the first node, the second node, the third node, the fourth node, the first thermal resistance, the second thermal resistance and the third thermal resistance.

[0023] On the other hand, the connection relationship of the equivalent heat transfer model includes:

[0024] The first end of the first power is respectively connected to the first end of the first heat capacitor and the first end of the first thermal resistor, and the common end of the connections is a first node; the second end of the first thermal resistor is respectively connected to the first end of the second power, the first end of the second heat capacitor and the first end of the second thermal resistor, and the common end of the connections is a second node; the second end of the second thermal resistor is connected to the first end of the third heat capacitor and the first end of the third thermal resistor, and the common end of the connections is a third node; the second end of the third thermal resistor is a fourth node; the second end of the first power, the second end of the first heat capacitor, the second end of the second power, the second end of the second heat capacitor and the second end of the third heat capacitor are connected, and the common end of the connections is grounded.

[0025] On the other hand, determining the reduced power of the heater based on the equivalent heat transfer model comprises:

[0026] A heat transfer relationship is constructed based on the first node, the second node and the third node in the equivalent heat transfer model. The heat transfer relationship includes , and ;

[0027] Among them, q dut is the first power, q h For the second power, C dut is the first heat capacity, C h is the second heat capacity, C a is the third heat capacity, T dut is the first node, T h is the second node, T a is the third node, T s is the fourth node, R 1 is the first thermal resistance, R 2 The second thermal resistance, R 3 is the third thermal resistance;

[0028] The heat transfer equation is obtained according to the heat transfer relationship, and the expression of the heat transfer equation is: ;

[0029] The reduced power of the heater is determined based on the heat transfer equation.

[0030] On the other hand, it also includes:

[0031] Determine the reference power of the heater to heat the magnetic element to a preset temperature before controlling the excitation source to excite the magnetic element. The expression of the reference power is: ;

[0032] Determine the expression of the steady-state power of the magnetic element in a stable state after the control excitation source excites the magnetic element, and the expression of the steady-state power is q=q base -q h ;

[0033] The heat transfer equation is processed according to the reference power and the steady-state power. The expression of the processed heat transfer equation is: ;

[0034] Among them, q base is the reference power, q is the steady-state power, τ is the time constant, , ;

[0035] Determining the reduced power of the heater based on the heat transfer equation includes:

[0036] The reduced power of the heater is determined based on the processed heat transfer equation.

[0037] On the other hand, determining the reduced power of the heater based on the processed heat transfer equation comprises:

[0038] Determine the expression of the steady-state power, the expression of the steady-state power is ;

[0039] Among them, q(t 0 ) is the power value of the magnetic element at the initial moment;

[0040] The reduced power of the heater is determined according to the expression of the steady-state power and the processed expression of the heat transfer equation.

[0041] In order to solve the above technical problems, the present invention also provides a magnetic element loss measurement system, comprising:

[0042] A heating unit, used for controlling the heater to heat the magnetic element to a preset temperature;

[0043] a temperature difference determining unit, used to determine a temperature difference between the magnetic element and a heat equalizing block disposed on a surface of the magnetic element;

[0044] An excitation unit, used for controlling an excitation source to excite the magnetic element;

[0045] A power control unit, used for controlling the power of the heater to decrease so that the temperature difference remains constant;

[0046] The power determination unit is used to determine the reduced power of the heater, where the reduced power of the heater is equal to the power loss of the magnetic element.

[0047] In order to solve the above technical problems, the present invention also provides a device for measuring magnetic element loss, comprising:

[0048] Memory for storing computer programs;

[0049] A processor is used to implement the steps of the above-mentioned method for measuring magnetic component loss when executing the computer program.

[0050] In order to solve the above technical problems, the present invention also provides a magnetic component loss measuring device, comprising the above magnetic component loss measuring device, and also comprising a heater, a heat equalizing block and an excitation source;

[0051] The heater covers the surface of the magnetic element and is used to heat the magnetic element;

[0052] The heat equalizing block covers the surface of the heater and is used to make the temperature of the surface of the magnetic element uniform;

[0053] The excitation source is connected to the magnetic element and is used to apply excitation to the magnetic element.

[0054] On the other hand, it also includes an electric control box, wherein the heater is a resistance wire;

[0055] The resistance wire is wound around the upper surface and the lower surface of the magnetic element, and the heat-matching block covers the resistance wire on the upper surface of the magnetic element and the resistance wire on the lower surface of the magnetic element respectively;

[0056] The electric control box is used to control the heating of the resistance wire.

[0057] On the other hand, it also includes a heat sink and a constant temperature device;

[0058] The constant temperature device is connected to the heat sink, and the heat sink covers the heat equalizing block on the upper surface of the magnetic element and the heat equalizing block on the lower surface of the magnetic element respectively;

[0059] The constant temperature device is used to provide a constant temperature for the heat sink, and the temperature of the heat sink is the same as the temperature of the heat block.

[0060] On the other hand, it also includes incubators;

[0061] The heater, the heat-saturating block, the magnetic element and the heat sink are all arranged inside the heat preservation box, and the magnetic element loss measuring device, the constant temperature device and the electric control box are all arranged outside the heat preservation box;

[0062] The surface of the heat preservation box is covered with heat preservation material to keep the temperature inside the heat preservation box constant.

[0063] In order to solve the above technical problems, the present invention also 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 magnetic component loss measurement method are implemented.

[0064] The present invention discloses a method for measuring the loss of a magnetic element and related components, and relates to the field of power electronic magnetic technology, including controlling a heater to heat a magnetic element to a preset temperature; determining the temperature difference between the magnetic element and a heat equalizing block arranged on the surface of the magnetic element; controlling an excitation source to excite the magnetic element; controlling the power of the heater to decrease to keep the temperature difference constant; determining the power decreased by the heater, which is equal to the power loss of the magnetic element. When the excitation source excites the magnetic element, the loss of the magnetic element is dissipated in the form of heat, and the temperature rise of the magnetic element will increase the temperature difference between the magnetic element and the heat equalizing block. At this time, the power of the heater is controlled to decrease. Under the condition of a constant temperature difference, the power reduced by the heater is equal to the power of the magnetic element when the temperature rises. In this way, the power loss of the magnetic element can be determined without considering the electrical characteristics of the magnetic element. The result obtained by measuring from the perspective of constant heat is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] 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.

[0066] Figure 1 A flow chart of a method for measuring magnetic component loss provided by the present invention;

[0067] Figure 2 A schematic diagram of the structure of a magnetic element loss measuring device provided by the present invention;

[0068] Figure 3 A structural schematic diagram of an equivalent heat transfer model provided by the present invention;

[0069] Figure 4 A schematic diagram of the structure of a magnetic element loss measurement system provided by the present invention;

[0070] Figure 5 A schematic structural diagram of a device for measuring magnetic element loss provided by the present invention. DETAILED DESCRIPTION

[0071] The core of the present invention is to provide a method for measuring the loss of a magnetic element and related components, which does not need to consider the electrical characteristics of the magnetic element. The heat generated by the magnetic element is used to measure its loss, and the result obtained is more accurate.

[0072] 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.

[0073] Figure 1 A flow chart of a method for measuring magnetic component loss provided by the present invention, Figure 2 A schematic diagram of the structure of a magnetic element loss measuring device provided by the present invention;

[0074] The measurement method of the magnetic component loss includes:

[0075] S11: Control the heater to heat the magnetic element to a preset temperature;

[0076] S12: determining a temperature difference between the magnetic element and a heat-saturating block disposed on a surface of the magnetic element;

[0077] When the heater heats the magnetic element, the temperature of the magnetic element will rise. A heat equalizing block is arranged on the surface of the magnetic element, a heat sink is arranged on the surface of the heat equalizing block, the heat sink is connected to the thermostat, and the heater is connected to the electric control box. Since the thermostat is connected to the heat sink, the temperature of the heat sink is constant, and the function of the heat sink is to maintain the heat equalizing block on the surface of the magnetic element at a constant temperature. In the process of the temperature rising of the magnetic element, a temperature difference will be generated between the magnetic element and the heat equalizing block.

[0078] It should be noted that the method of controlling the heater to heat the magnetic element is to use an electric control box to control the heater to heat the magnetic element, and the heating power can be determined according to the electric control box.

[0079] S13: controlling the excitation source to excite the magnetic element;

[0080] When a high-frequency excitation source is used to excite the magnetic element, the magnetic element will produce losses, causing its own temperature to rise. Since the temperature of the heat equalizing block is constant, the temperature difference between the magnetic element and the heat equalizing block will become larger.

[0081] S14: Control the power of the heater to decrease so as to keep the temperature difference constant;

[0082] S15: Determine the reduced power of the heater, where the reduced power of the heater is equal to the power loss of the magnetic element.

[0083] Use the electric control box to reduce the power of the heater. When the reduced power is equal to the loss of the magnetic element, the temperature difference between the magnetic part to be tested and the heat-saturated block remains unchanged. The reduced power of the heater is the loss of the magnetic part to be tested. During the entire experiment, ensure that the temperature difference between the magnetic part to be tested and the heat-saturated block remains stable.

[0084] Please refer to Figure 2 The magnetic component to be tested is placed in a test box made of insulation materials of appropriate size. A heat spreader and a heater are arranged inside the box. The heat spreader is provided with a constant temperature by a thermostat, and the surface of the heat spreader is covered with aluminum foil to even out the surface temperature of the magnetic component and reduce the error caused by radiation heat transfer. The heater is composed of a resistance wire with a large surface area and is wound around the magnetic component. When the heater works, it heats the magnetic component to the target temperature, forming a temperature difference with the heat spreader. Under ideal conditions, the loss of the magnetic component under test after high-frequency excitation is completely converted into heat, causing the surface temperature of the magnetic component to rise. The power of the heater is reduced to keep the temperature difference between the magnetic component and the heat spreader constant. The reduced heater power is the loss power of the magnetic component.

[0085] The constant temperature device can be implemented in the form of a constant temperature water bath or a constant temperature oil bath.

[0086] The present invention discloses a method for measuring the loss of a magnetic element, which relates to the field of power electronic magnetic technology, and includes controlling a heater to heat a magnetic element to a preset temperature; determining the temperature difference between the magnetic element and a heat equalizing block arranged on the surface of the magnetic element; controlling an excitation source to excite the magnetic element; controlling the power of the heater to decrease to keep the temperature difference constant; and determining the power decreased by the heater, which is equal to the power loss of the magnetic element. When the excitation source excites the magnetic element, the loss of the magnetic element is dissipated in the form of heat, and the temperature rise of the magnetic element will increase the temperature difference between the magnetic element and the heat equalizing block. At this time, the power of the heater is controlled to decrease. Under the condition of a constant temperature difference, the power decreased by the heater is equal to the power increased by the temperature of the magnetic element. In this way, the power loss of the magnetic element can be determined without considering the electrical characteristics of the magnetic element. The result obtained by measuring from the perspective of constant heat is more accurate.

[0087] Based on the above embodiments:

[0088] In some embodiments, determining a temperature difference between a magnetic element and a heat sink disposed on a surface of the magnetic element includes:

[0089] When the heater is controlled to heat the magnetic element to a preset temperature, the temperature difference relationship is determined according to the power and specific heat capacity coefficient of the heater. The temperature difference relationship is: ;

[0090] When the excitation source is controlled to excite the magnetic element, the temperature difference relationship is determined according to the power and specific heat capacity coefficient of the heater. The temperature difference relationship is: ;

[0091] Among them, P 1 is the power of the heater in the process of heating the magnetic element to the preset temperature, k is the specific heat capacity coefficient, ΔT is the temperature difference, P 磁元件 is the power loss of the magnetic component, P 2 is the power of the heater after the power of the heater is reduced.

[0092] In the first stage, only the heater heats the magnetic element, so the heater power P 1 Under the action of, a temperature difference ΔT will be formed between the magnetic part to be tested and the heat equalization block, where k is a coefficient related to the mass and specific heat capacity of the object. 1 It is the power generated by the heater and is easy to obtain.

[0093] In the second stage, not only the heater heats the magnetic element, but also the magnetic element is lost in the form of heat after being excited. 2 It is the power generated by the heater, which is easy to obtain. So the power loss of the magnetic component P 代测件 =P1-P2.

[0094] Figure 3 A structural schematic diagram of an equivalent heat transfer model provided by the present invention;

[0095] In some embodiments, a heat sink is further disposed on a side of the heat block away from the magnetic element, and determining the reduced power of the heater includes:

[0096] Construct an equivalent heat transfer model between magnetic elements, heaters, heat sinks and heat sinks;

[0097] The reduced power of the heater is determined based on the equivalent heat transfer model.

[0098] During the measurement process, since the magnetic element to be measured has a large heat capacity, the measurement of the heat generated by the magnetic element due to loss has a certain hysteresis effect, which makes the measurement result unable to be directly equivalent to the transient heat generated by the magnetic component. Thermal balance analysis is the basis for calculating the accuracy of heat generation of the magnetic element to be measured. Under the premise of ignoring convection heat dissipation, the equivalent heat transfer model of the measuring device can be obtained according to heat transfer theory.

[0099] In some embodiments, an equivalent heat transfer model between a magnetic element, a heater, a heat block, and a heat sink is constructed, including:

[0100] The heat generation power of the magnetic element is equivalent to the first power, and the power of the heater is equivalent to the second power;

[0101] The specific heat capacity of the magnetic element is equivalent to the first heat capacity, the specific heat capacity of the heater is equivalent to the second heat capacity, and the specific heat capacity of the heat equalizing block is equivalent to the third heat capacity;

[0102] The temperature of the magnetic element is equivalent to the first node, the temperature of the heater is equivalent to the second node, the temperature of the heat equalization block is equivalent to the third node, and the temperature of the heat sink is equivalent to the fourth node;

[0103] The thermal resistance between the magnetic element and the heater is equivalent to the first thermal resistance, the thermal resistance between the heater and the heat equalizing block is equivalent to the second thermal resistance, and the thermal resistance between the heat sink and the heat equalizing block is equivalent to the third thermal resistance;

[0104] An equivalent heat transfer model between the magnetic element, the heater, the heat equalizing block and the heat sink is constructed according to the first power, the second power, the first heat capacity, the second heat capacity, the third heat capacity, the first node, the second node, the third node, the fourth node, the first thermal resistance, the second thermal resistance and the third thermal resistance.

[0105] In some embodiments, the connection relationship of the equivalent heat transfer model includes:

[0106] The first end of the first power is connected to the first end of the first heat capacitor and the first end of the first thermal resistor respectively, and the common end of the connections is the first node. The second end of the first thermal resistor is connected to the first end of the second power, the first end of the second heat capacitor and the first end of the second thermal resistor respectively, and the common end of the connections is the second node. The second end of the second thermal resistor is connected to the first end of the third heat capacitor and the first end of the third thermal resistor, and the common end of the connections is the third node. The second end of the third thermal resistor is the fourth node. The second end of the first power, the second end of the first heat capacitor, the second end of the second power, the second end of the second heat capacitor and the second end of the third heat capacitor are connected, and the common end of the connections is grounded.

[0107] In some embodiments, determining the reduced power of the heater based on an equivalent heat transfer model includes:

[0108] The heat transfer equation is constructed based on the first node, the second node and the third node in the equivalent heat transfer model. The heat transfer equation includes , and ;

[0109] Among them, q dut is the first power (power of the magnetic element to be measured), q h is the second power (the power applied by the heater), C dut is the first thermal capacitance (thermal capacitance of the magnetic element to be measured), C h is the second heat capacity (heat capacity of the heater), C a is the third heat capacity (heat capacity of the heat equalization block), T dut is the first node, T h is the second node, T a is the third node, T s is the fourth node, R 1 is the first thermal resistance (the thermal resistance between the magnetic part to be tested and the heater), R2 is the second thermal resistance (thermal resistance between heater and heat sink), R 3 is the third thermal resistance (thermal resistance between heat sink and heat equalizing block);

[0110] According to the heat transfer relationship, the heat transfer equation is obtained. The expression of the heat transfer equation is: ;

[0111] The reduced power of the heater is determined based on the heat transfer equation.

[0112] According to Kirchhoff's law and thermoelectric analogy theory, at T dut 、T h and T a At the node, a heat transfer relationship can be established. According to the principle of isothermal calorimetry, T a and T s Keeping it constant, its derivative is zero, and the heat transfer equation can be obtained through the heat transfer relationship.

[0113] In some embodiments, it also includes:

[0114] Determine the reference power of the heater to heat the magnetic element to a preset temperature before the control excitation source excites the magnetic element. The expression of the reference power is: ;

[0115] Determine the expression of the steady-state power of the magnetic element in a stable state after the control excitation source excites the magnetic element. The expression of the steady-state power is q=q base -q h ;

[0116] According to the reference power and steady-state power, the heat transfer equation is processed. The expression of the processed heat transfer equation is: ;

[0117] Among them, q base is the reference power, q is the steady-state power, τ is the time constant, , ;

[0118] The reduced power of the heater is determined based on the heat transfer equation, including:

[0119] The reduced power of the heater is determined based on the processed heat transfer equation.

[0120] When the magnetic part is not excited by high frequency, the power of the heater when heating the magnetic part to the target temperature is the reference power q base , time constant It is the key factor affecting the dynamic performance of the calorimetric device.

[0121] The heat transfer equation can then be rewritten as , and since q=q base -qh , so the heat transfer equation can be further rewritten as ,because , so after processing the heat transfer equation, we finally get .

[0122] In some embodiments, determining the reduced power of the heater based on the processed heat transfer equation includes:

[0123] Determine the expression for steady-state power. The expression for steady-state power is ;

[0124] Among them, q(t 0 ) is the power value of the magnetic element at the initial moment;

[0125] The reduced power of the heater is determined based on the expression of the steady-state power and the processed expression of the heat transfer equation.

[0126] Regarding the first-order dynamic response expression of q, when the magnetic part to be tested does not generate heat, one solution can be obtained as q=0, then q can be expressed as: , by logarithmic operation we can get , the time constant τ in the formula can be obtained by linear fitting. Then the time constant and the filtered dq / dt are substituted into The heat generation power of the device under test can be obtained.

[0127] Figure 4 A schematic diagram of the structure of a magnetic component loss measurement system provided by the present invention, the magnetic component loss measurement system comprising:

[0128] A heating unit 41, used to control the heater to heat the magnetic element to a preset temperature;

[0129] A temperature difference determination unit 42, used to determine a temperature difference between the magnetic element and a heat equalization block disposed on the surface of the magnetic element;

[0130] An excitation unit 43, used to control an excitation source to excite the magnetic element;

[0131] A power control unit 44, used to control the power of the heater to decrease so that the temperature difference remains constant;

[0132] The power determination unit 45 is used to determine the reduced power of the heater, where the reduced power of the heater is equal to the power loss of the magnetic element.

[0133] For an introduction to the magnetic component loss measurement system provided in the present application, please refer to the above-mentioned embodiments, which will not be described in detail here.

[0134] Based on the above embodiments:

[0135] The temperature difference determination unit 42 is specifically used to determine the temperature difference relationship according to the power and specific heat capacity coefficient of the heater when controlling the heater to heat the magnetic element to a preset temperature. The temperature difference relationship is: ;

[0136] When the excitation source is controlled to excite the magnetic element, the temperature difference relationship is determined according to the power and specific heat capacity coefficient of the heater. The temperature difference relationship is: ;

[0137] Among them, P 1 is the power of the heater in the process of heating the magnetic element to the preset temperature, k is the specific heat capacity coefficient, ΔT is the temperature difference, P 磁元件 is the power loss of the magnetic component, P 2 is the power of the heater after the power of the heater is reduced.

[0138] A heat sink is also provided on one side of the heat equalizing block away from the magnetic element;

[0139] An equivalent heat transfer model building unit is used to build an equivalent heat transfer model between magnetic elements, heaters, heat equalizing blocks and heat sinks;

[0140] The power determination unit 45 is specifically configured to determine the reduced power of the heater based on an equivalent heat transfer model.

[0141] An equivalent heat transfer model building unit, specifically used to equate the heat generation power of the magnetic element to the first power, and the power of the heater to the second power;

[0142] The specific heat capacity of the magnetic element is equivalent to the first heat capacity, the specific heat capacity of the heater is equivalent to the second heat capacity, and the specific heat capacity of the heat equalizing block is equivalent to the third heat capacity;

[0143] The temperature of the magnetic element is equivalent to the first node, the temperature of the heater is equivalent to the second node, the temperature of the heat equalization block is equivalent to the third node, and the temperature of the heat sink is equivalent to the fourth node;

[0144] The thermal resistance between the magnetic element and the heater is equivalent to the first thermal resistance, the thermal resistance between the heater and the heat equalizing block is equivalent to the second thermal resistance, and the thermal resistance between the heat sink and the heat equalizing block is equivalent to the third thermal resistance;

[0145] An equivalent heat transfer model between the magnetic element, the heater, the heat equalizing block and the heat sink is constructed according to the first power, the second power, the first heat capacity, the second heat capacity, the third heat capacity, the first node, the second node, the third node, the fourth node, the first thermal resistance, the second thermal resistance and the third thermal resistance.

[0146] The connections of the equivalent heat transfer model include:

[0147] The first end of the first power is connected to the first end of the first heat capacitor and the first end of the first thermal resistor respectively, and the common end of the connections is the first node. The second end of the first thermal resistor is connected to the first end of the second power, the first end of the second heat capacitor and the first end of the second thermal resistor respectively, and the common end of the connections is the second node. The second end of the second thermal resistor is connected to the first end of the third heat capacitor and the first end of the third thermal resistor, and the common end of the connections is the third node. The second end of the third thermal resistor is the fourth node. The second end of the first power, the second end of the first heat capacitor, the second end of the second power, the second end of the second heat capacitor and the second end of the third heat capacitor are connected, and the common end of the connections is grounded.

[0148] The heat transfer relationship determination unit is used to construct a heat transfer relationship based on the first node, the second node and the third node in the equivalent heat transfer model. The heat transfer relationship includes , and ;

[0149] Among them, q dut is the first power (power of the magnetic element to be measured), q h is the second power (the power applied by the heater), C dut is the first thermal capacitance (thermal capacitance of the magnetic element to be measured), C h is the second heat capacity (heat capacity of the heater), C a is the third heat capacity (heat capacity of the heat equalizing block), T dut is the first node, T h is the second node, T a is the third node, T s is the fourth node, R 1 is the first thermal resistance (the thermal resistance between the magnetic part to be tested and the heater), R 2 is the second thermal resistance (thermal resistance between heater and heat sink), R 3 is the third thermal resistance (thermal resistance between heat sink and heat equalizing block);

[0150] The heat transfer equation determination unit is used to obtain the heat transfer equation based on the heat transfer relationship. The expression of the heat transfer equation is: ;

[0151] The power determination unit 45 is specifically configured to determine the reduced power of the heater based on a heat transfer equation.

[0152] The reference power determination unit is used to determine the reference power of the heater to heat the magnetic element to a preset temperature before the control excitation source excites the magnetic element. The expression of the reference power is: ;

[0153] The steady-state power determination unit is used to determine the expression of the steady-state power of the magnetic element in a stable state after the control excitation source excites the magnetic element. The expression of the steady-state power is q=qbase -q h ;

[0154] According to the reference power and steady-state power, the heat transfer equation is processed. The expression of the processed heat transfer equation is: ;

[0155] Among them, q base is the reference power, q is the steady-state power, τ is the time constant, , ;

[0156] The power determination unit 45 is specifically configured to determine the reduced power of the heater based on the processed heat transfer equation.

[0157] The steady-state power expression determination unit is used to determine the steady-state power expression. The steady-state power expression is: ;

[0158] Among them, q(t 0 ) is the power value of the magnetic element at the initial moment;

[0159] The power determination unit 45 is specifically used to determine the reduced power of the heater according to the expression of the steady-state power and the processed expression of the heat transfer equation.

[0160] Figure 5 A schematic diagram of the structure of a magnetic element loss measuring device provided by the present invention, the magnetic element loss measuring device comprising:

[0161] A memory 51, used for storing computer programs;

[0162] The processor 52 is used to implement the steps of the above-mentioned method for measuring the loss of magnetic components when executing the computer program.

[0163] For an introduction to the device for measuring magnetic component loss provided in the present application, please refer to the above-mentioned embodiments, which will not be described in detail here.

[0164] Figure 2 A schematic diagram of the structure of a magnetic component loss measuring device provided by the present invention, the magnetic component loss measuring device comprises the above-mentioned magnetic component loss measuring device, and also comprises a heater 1, a heat equalizing block 2 and an excitation source 3;

[0165] The heater 1 covers the surface of the magnetic element and is used for heating the magnetic element;

[0166] The heat-homing block 2 covers the surface of the heater 1 and is used to make the surface temperature of the magnetic element uniform;

[0167] The excitation source 3 is connected to the magnetic element and is used to apply excitation to the magnetic element.

[0168] In some embodiments, an electric control box 4 is also included, and the heater 1 is a resistance wire;

[0169] The resistance wire is wound on the upper surface and the lower surface of the magnetic element, and the heat-saturating block 2 covers the resistance wire on the upper surface of the magnetic element and the resistance wire on the lower surface of the magnetic element respectively;

[0170] The electric control box 4 is used to control the heating of the resistance wire.

[0171] In some embodiments, a heat sink 5 and a constant temperature device 6 are also included;

[0172] The constant temperature device 6 is connected to the heat sink 5, and the heat sink 5 covers the heat equalizing block 2 on the upper surface of the magnetic element and the heat equalizing block 2 on the lower surface of the magnetic element respectively;

[0173] The thermostat 6 is used to provide a constant temperature for the heat sink 5 . The temperature of the heat sink 5 is the same as the temperature of the heat block 2 .

[0174] In some embodiments, an incubator 7 is also included;

[0175] The heater 1, the heat absorbing block 2, the magnetic element and the heat sink 5 are all arranged inside the heat preservation box 7, and the measuring device for the magnetic element loss, the constant temperature device 6 and the electric control box 4 are all arranged outside the heat preservation box 7;

[0176] The surface of the heat preservation box 7 is covered with heat preservation material to keep the temperature inside the heat preservation box 7 constant.

[0177] The magnetic element to be tested is placed in an insulation box 7 made of insulation materials of suitable size. A heat equalizer 2 and a heater 1 are arranged inside the insulation box 7. The heat equalizer 2 is provided with a constant temperature by a thermostat 6 through an oil bath or a water bath, and the surface of the heat equalizer 2 is covered with aluminum foil to even out the surface temperature of the magnetic element and reduce the error caused by radiation heat transfer. The heater 1 is composed of a resistance wire with a large surface area and is wound around the magnetic element. The heater 1 works to heat the magnetic element to the target temperature, forming a temperature difference with the heat equalizer 2. Under ideal conditions, the loss of the magnetic element after high-frequency excitation is completely converted into heat, causing the surface temperature of the magnetic element to rise. The power of the heater 1 is reduced to make the temperature difference between the piece to be tested and the heat equalizer constant. The reduced power of the heater 1 is the loss power of the magnetic element.

[0178] The present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above-mentioned method for measuring magnetic element loss are implemented.

[0179] 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.

[0180] 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.

[0181] 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.

[0182] 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 measuring magnetic component loss, characterized in that: include: Controlling the heater to heat the magnetic element to a preset temperature; Determining a temperature difference between the magnetic element and a heat spreader disposed on a surface of the magnetic element; Controlling an excitation source to excite the magnetic element; Controlling the power of the heater to decrease so as to keep the temperature difference constant; A reduced power of the heater is determined, the reduced power of the heater being equal to the power loss of the magnetic element.

2. The method for measuring magnetic component loss according to claim 1, characterized in that: Determining a temperature difference between the magnetic element and a heat-saturating block disposed on a surface of the magnetic element comprises: When the heater is controlled to heat the magnetic element to a preset temperature, the temperature difference relationship is determined according to the power and specific heat capacity coefficient of the heater. The temperature difference relationship is: ; When the excitation source is controlled to excite the magnetic element, the temperature difference relationship is determined according to the power and specific heat capacity coefficient of the heater. The temperature difference relationship is: ; Wherein, P1 is the power of the heater in the process of heating the magnetic element to a preset temperature, k is the specific heat capacity coefficient, ΔT is the temperature difference, and P 磁元件 is the power loss of the magnetic element, and P2 is the power of the heater after the power of the heater is reduced.

3. The method for measuring magnetic element loss according to claim 1 or 2, characterized in that: A heat sink is further disposed on a side of the heat equalizing block away from the magnetic element, and determining the reduced power of the heater includes: Constructing an equivalent heat transfer model among the magnetic element, the heater, the heat equalizing block and the heat sink; The reduced power of the heater is determined based on the equivalent heat transfer model.

4. The method for measuring magnetic element loss according to claim 3, characterized in that: Constructing an equivalent heat transfer model between the magnetic element, the heater, the heat equalizing block and the heat sink, including: The heat generation power of the magnetic element is equivalent to the first power, and the power of the heater is equivalent to the second power; The specific heat capacity of the magnetic element is equivalent to the first heat capacity, the specific heat capacity of the heater is equivalent to the second heat capacity, and the specific heat capacity of the heat equalizing block is equivalent to the third heat capacity; The temperature of the magnetic element is equivalent to the first node, the temperature of the heater is equivalent to the second node, the temperature of the heat block is equivalent to the third node, and the temperature of the heat sink is equivalent to the fourth node; The thermal resistance between the magnetic element and the heater is equivalent to a first thermal resistance, the thermal resistance between the heater and the heat equalizing block is equivalent to a second thermal resistance, and the thermal resistance between the heat sink and the heat equalizing block is equivalent to a third thermal resistance; An equivalent heat transfer model between the magnetic element, the heater, the heat equalizing block and the heat sink is constructed according to the first power, the second power, the first heat capacitance, the second heat capacitance, the third heat capacitance, the first node, the second node, the third node, the fourth node, the first thermal resistance, the second thermal resistance and the third thermal resistance.

5. The method for measuring magnetic component loss according to claim 4, characterized in that: The connection relationship of the equivalent heat transfer model includes: The first end of the first power is respectively connected to the first end of the first heat capacitor and the first end of the first thermal resistor, and the common end of the connections is a first node; the second end of the first thermal resistor is respectively connected to the first end of the second power, the first end of the second heat capacitor and the first end of the second thermal resistor, and the common end of the connections is a second node; the second end of the second thermal resistor is connected to the first end of the third heat capacitor and the first end of the third thermal resistor, and the common end of the connections is a third node; the second end of the third thermal resistor is a fourth node; the second end of the first power, the second end of the first heat capacitor, the second end of the second power, the second end of the second heat capacitor and the second end of the third heat capacitor are connected, and the common end of the connections is grounded.

6. The method for measuring magnetic component loss according to claim 4, characterized in that: Determining the reduced power of the heater based on the equivalent heat transfer model includes: A heat transfer relationship is constructed based on the first node, the second node and the third node in the equivalent heat transfer model. The heat transfer relationship includes , and ; Among them, q dut is the first power, q h For the second power, C dut is the first heat capacity, C h is the second heat capacity, C a is the third heat capacity, T dut is the first node, T h is the second node, T a is the third node, T s is the fourth node, R1 is the first thermal resistance, R2 is the second thermal resistance, and R3 is the third thermal resistance; The heat transfer equation is obtained according to the heat transfer relationship, and the expression of the heat transfer equation is: ; The reduced power of the heater is determined based on the heat transfer equation.

7. The method for measuring magnetic element loss according to claim 6, characterized in that: Also includes: Determine the reference power of the heater to heat the magnetic element to a preset temperature before controlling the excitation source to excite the magnetic element. The expression of the reference power is: ; Determine the expression of the steady-state power of the magnetic element in a stable state after the control excitation source excites the magnetic element, and the expression of the steady-state power is q=q base -q h ; The heat transfer equation is processed according to the reference power and the steady-state power. The expression of the processed heat transfer equation is: ; Among them, q base is the reference power, q is the steady-state power, τ is the time constant, , ; Determining the reduced power of the heater based on the heat transfer equation includes: The reduced power of the heater is determined based on the processed heat transfer equation.

8. The method for measuring magnetic component loss according to claim 7, characterized in that: Determining the reduced power of the heater based on the processed heat transfer equation includes: Determine the expression of the steady-state power, the expression of the steady-state power is ; Wherein, q(t0) is the power value of the magnetic element at the initial moment; The reduced power of the heater is determined according to the expression of the steady-state power and the expression of the processed heat transfer equation.

9. A magnetic component loss measurement system, characterized in that: include: A heating unit, used for controlling the heater to heat the magnetic element to a preset temperature; a temperature difference determining unit, used to determine a temperature difference between the magnetic element and a heat equalizing block disposed on a surface of the magnetic element; An excitation unit, used for controlling an excitation source to excite the magnetic element; A power control unit, used for controlling the power of the heater to decrease so that the temperature difference remains constant; The power determination unit is used to determine the reduced power of the heater, where the reduced power of the heater is equal to the power loss of the magnetic element.

10. A device for measuring magnetic element loss, characterized in that: include: Memory for storing computer programs; A processor, configured to implement the steps of the method for measuring magnetic component loss as claimed in any one of claims 1 to 8 when executing the computer program.

11. A device for measuring magnetic component loss, characterized in that: A device for measuring magnetic element loss as claimed in claim 10, further comprising a heater, a heat block and an excitation source; The heater covers the surface of the magnetic element and is used to heat the magnetic element; The heat equalizing block covers the surface of the heater and is used to make the temperature of the surface of the magnetic element uniform; The excitation source is connected to the magnetic element and is used to apply excitation to the magnetic element.

12. The magnetic element loss measuring device according to claim 11, characterized in that: It also includes an electric control box, wherein the heater is a resistance wire; The resistance wire is wound around the upper surface and the lower surface of the magnetic element, and the heat-matching block covers the resistance wire on the upper surface of the magnetic element and the resistance wire on the lower surface of the magnetic element respectively; The electric control box is used to control the heating of the resistance wire.

13. The magnetic component loss measuring device according to claim 12, characterized in that: It also includes a heat sink and a constant temperature device; The constant temperature device is connected to the heat sink, and the heat sink covers the heat equalizing block on the upper surface of the magnetic element and the heat equalizing block on the lower surface of the magnetic element respectively; The constant temperature device is used to provide a constant temperature for the heat sink, and the temperature of the heat sink is the same as the temperature of the heat block.

14. The magnetic component loss measuring device according to any one of claims 11 to 13, characterized in that: Also includes incubator; The heater, the heat-saturating block, the magnetic element and the heat sink are all arranged inside the heat preservation box, and the magnetic element loss measuring device, the constant temperature device and the electric control box are all arranged outside the heat preservation box; The surface of the heat preservation box is covered with heat preservation material to keep the temperature inside the heat preservation box constant.

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 measuring the loss of a magnetic element according to any one of claims 1 to 8 are implemented.

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