Inductance detection circuit, method, device, computer storage medium and electrical equipment

Abstract

The present application provides an inductance detection circuit, method, device, computer storage medium and electrical equipment, wherein the inductance detection circuit includes a voltage conversion circuit, a resistor, a resonant capacitor, a detection circuit and a controller. The resistor and the inductance to be measured are both electrically connected to the voltage conversion circuit. The resonant capacitor and the inductance to be measured form an LC resonant circuit. The controller is used to control the voltage conversion circuit to invert the DC voltage provided by the DC power supply into an AC voltage with a frequency of a target frequency, and to determine the inductance of the inductance to be measured based on the capacitance value of the resonant capacitor and the target frequency when at least one of the capacitance value of the resonant capacitor and the resistance value of the resistor is adjusted, when the load current is equal to the target load current and the LC resonant circuit is determined to be in a resonant state based on the capacitor voltage and the load voltage. The inductance detection circuit provided in the present application can detect the inductance of the inductance to be measured at any frequency and any load current.

Description

Technical Field

[0001] The present application relates to the technical field of inductance detection, and in particular to an inductance detection circuit, method, device, computer storage medium and electrical equipment. Background Art

[0002] Inductor components have been widely used in radio frequency and microwave circuits. The types of inductors include air-core inductors and magnetic ring inductors. Among them, magnetic ring inductors are air-core inductors with magnetic isolation sheets or iron cores inserted into them, so they have stronger self-inductance.

[0003] The inductance (L value) of an inductor is theoretically determined by its physical structure and material properties. For an ideal inductor, its inductance is constant. However, in practical applications, since the inductor is affected by parasitic capacitance effects, core saturation and other factors, the inductance of the inductor will change with changes in frequency and load current. However, the existing inductance detection circuit can only detect the inductance of the inductor at a fixed frequency and fixed current, which cannot meet the measurement requirements. Summary of the invention

[0004] In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides an inductance detection circuit, method, device, computer storage medium and electrical equipment.

[0005] To achieve the above object, a first aspect of the present application provides an inductance detection circuit, wherein the inductance detection circuit is used to detect the inductance of an inductor to be tested when a target load current of a target frequency flows through the inductance detection circuit, and the inductance detection circuit comprises:

[0006] A voltage conversion circuit is electrically connected to the DC power supply;

[0007] A resistor, which is electrically connected to the voltage conversion circuit together with the inductor to be measured, and the resistance value of the resistor is adjustable;

[0008] A resonant capacitor, electrically connected to the inductor to be measured to form an LC resonant circuit, wherein the capacitance value of the resonant capacitor is adjustable;

[0009] A detection circuit, used to detect the load current flowing through the inductor to be measured, the capacitor voltage across the resonant capacitor, and the load voltage; wherein the load voltage is the sum of the voltage across the inductor to be measured and the voltage across the resistor; and

[0010] A controller is electrically connected to the voltage conversion circuit and the detection circuit, and is used to control the voltage conversion circuit to invert the DC voltage provided by the DC power supply into an AC voltage with a frequency of the target frequency, thereby outputting the AC voltage to the resistor and the inductor to be measured through the voltage conversion circuit; the controller is also used to determine the inductance of the inductor to be measured based on the capacitance value of the resonant capacitor and the target frequency when at least one of the capacitance value of the resonant capacitor and the resistance value of the resistor is adjusted, when the load current is equal to the target load current and it is determined according to the capacitor voltage and the load voltage that the LC resonant circuit is in a resonant state.

[0011] The inductance detection circuit provided by the present application controls the voltage conversion circuit through a controller to provide an alternating current with a target frequency to the inductor to be measured, adjusts the current flowing through the inductor to be measured to reach the target load current by setting a resistor with an adjustable resistance value, and achieves a resonant state with the inductor to be measured at the target frequency by setting a resonant capacitor with an adjustable capacitance value, and determines the inductance of the inductor to be measured according to the capacitance value of the resonant capacitor when the resonant state with the inductor to be measured reaches the target load current at the target frequency and the target frequency through the controller, thereby being able to detect the inductance of the inductor to be measured at any frequency and any load current, and the measurement circuit is simple and the measurement range is wider.

[0012] In some embodiments, the voltage conversion circuit includes:

[0013] a first input terminal and a second input terminal, wherein the first input terminal is electrically connected to the positive electrode of the DC power supply, and the second input terminal is electrically connected to the negative electrode of the DC power supply;

[0014] A first output terminal and a second output terminal, wherein the resistor and the inductor to be measured are connected in series between the first output terminal and the second output terminal;

[0015] The first branch and the second branch are both electrically connected to the first input terminal, the second input terminal, the first output terminal and the second output terminal; wherein the first branch and the second branch are alternately turned on according to the target frequency under the control of the controller, thereby inverting the DC voltage provided by the DC power supply into an AC voltage with a frequency of the target frequency, and outputting the AC voltage to the resistor and the inductor to be measured.

[0016] In some embodiments, the first branch includes:

[0017] A first switch tube is electrically connected between the first input terminal and the first output terminal; and

[0018] A second capacitor, electrically connected between the second output terminal and the second input terminal;

[0019] The second branch comprises:

[0020] A second switch tube is electrically connected between the first output terminal and the second input terminal; and

[0021] A first capacitor, electrically connected between the first input terminal and the second output terminal;

[0022] The resonant capacitor includes a first capacitor and a second capacitor in the voltage conversion circuit, and the capacitance value of the first capacitor and the capacitance value of the second capacitor are both adjustable.

[0023] In some embodiments, the detection circuit is specifically used to detect the load current, the first voltage across the first capacitor, the second voltage across the second capacitor, and the load voltage;

[0024] The controller is electrically connected to the first switch tube and the second switch tube, and is used to control the first switch tube and the second switch tube to be alternately turned on according to the target frequency, so as to invert the DC voltage provided by the DC power supply into an AC voltage with a frequency of the target frequency; in the process of adjusting at least one of the capacitance value of the first capacitor, the capacitance value of the second capacitor and the resistance value of the resistor, the controller is specifically used to determine the inductance of the inductor to be measured based on the capacitance value of the first capacitor, the capacitance value of the second capacitor and the target frequency when it is determined that the inductor to be measured and the first capacitor and the second capacitor are in a resonant state under the target load current according to the load current, the first voltage, the second voltage and the load voltage.

[0025] In some embodiments, the controller is specifically used to determine that the inductor to be measured and the first capacitor and the second capacitor are in a resonant state under the target load current when the effective value of the first voltage, the effective value of the second voltage and the effective value of the load voltage are all equal and the load current is equal to the target load current.

[0026] In some embodiments, the controller is specifically used to determine the inductance of the inductor to be measured according to a first preset resonance formula based on the capacitance value of the first capacitor, the capacitance value of the second capacitor and the target frequency; wherein the first preset resonance formula is L=1 / (4*π 2 *f 2 *(C1+C2)), wherein C1 is the capacitance value of the first capacitor when the LC resonant circuit is in the resonant state at the target load current, C2 is the capacitance value of the second capacitor when the LC resonant circuit is in the resonant state at the target load current, and f is the target frequency.

[0027] In some embodiments, the controller is specifically used to output a first control signal and a second control signal, both of which have the target frequency, to the first switch tube and the second switch tube, respectively, so as to control the first switch tube and the second switch tube to be alternately turned on according to the target frequency; wherein the duty cycle of the first control signal and the duty cycle of the second control signal are equal and less than or equal to 50%, and the phase of the first control signal differs by 180 degrees from the phase of the second control signal.

[0028] In some embodiments, the first branch includes:

[0029] A third switch tube is electrically connected between the first input terminal and the first output terminal; and

[0030] a sixth switch tube, electrically connected between the second output terminal and the second input terminal;

[0031] The second branch comprises:

[0032] a fourth switch tube, electrically connected between the first output terminal and the second input terminal; and

[0033] a fifth switch tube, electrically connected between the first input terminal and the second output terminal;

[0034] The resonant capacitor includes a third capacitor, and the third capacitor, the resistor, and the inductor to be measured are connected in series between the first output terminal and the second output terminal, and the capacitance value of the third capacitor is adjustable.

[0035] In some embodiments, the detection circuit is specifically used to detect the load current, the third voltage across the third capacitor, and the load voltage;

[0036] The controller is electrically connected to the third switch tube, the fourth switch tube, the fifth switch tube and the sixth switch tube, and is used to control the third switch tube and the fourth switch tube to be alternately turned on according to the target frequency, and control the fifth switch tube and the sixth switch tube to be alternately turned on according to the target frequency, so as to invert the DC voltage provided by the DC power supply into an AC voltage with a target frequency; wherein the on-off state of the third switch tube and the sixth switch tube is the same, and the on-off state of the fourth switch tube and the fifth switch tube is the same; in the process of adjusting at least one of the capacitance value of the third capacitor and the resistance value of the resistor, the controller is specifically used to determine the inductance of the inductor to be measured based on the capacitance value of the third capacitor and the target frequency when it is determined that the LC resonant circuit is in a resonant state under the target load current according to the load current, the third voltage and the load voltage.

[0037] In some embodiments, the controller is specifically used to determine that the LC resonant circuit is in a resonant state under a target load current when an effective value of the third voltage is equal to an effective value of the load voltage and the load current is equal to the target load current.

[0038] In some embodiments, the controller is specifically used to determine the inductance of the inductor to be measured based on the capacitance value of the third capacitor and the target frequency according to a second preset resonance formula; wherein the second preset resonance formula is L=1 / (4*π 2 *f 2 *C3), wherein C3 is the capacitance value of the third capacitor when the LC resonant circuit is in a resonant state under a target load current, and f is the target frequency.

[0039] In some embodiments, the controller is specifically used to output a third control signal with a frequency of the target frequency to the third switch tube and the sixth switch tube, and to output a fourth control signal with a frequency of the target frequency to the fourth switch tube and the fifth switch tube, so as to control the third switch tube and the fourth switch tube to be alternately turned on according to the target frequency, and to control the fifth switch tube and the sixth switch tube to be alternately turned on according to the target frequency; wherein the duty cycle of the third control signal is equal to the duty cycle of the fourth control signal and is less than or equal to 50%, and the phase of the third control signal differs by 180 degrees from the phase of the fourth control signal.

[0040] A second aspect of the present application further provides an inductance detection method, which is applied to the inductance detection circuit described in the first aspect above, and the inductance detection method includes:

[0041] Controlling the voltage conversion circuit to invert the DC voltage provided by the DC power supply into an AC voltage with a target frequency, thereby outputting the AC voltage to the resistor and the inductor to be measured through the voltage conversion circuit;

[0042] adjusting the capacitance value of the resonant capacitor and / or adjusting the resistance value of the resistor until the load current is equal to the target load current and the LC resonant circuit is determined to be in a resonant state according to the capacitor voltage and the load voltage, and then stopping the adjustment;

[0043] acquiring a capacitance value of the resonant capacitor when the LC resonant circuit is in a resonant state under the target load current; and

[0044] The inductance of the inductor to be measured is determined based on the capacitance value of the resonant capacitor and the target frequency.

[0045] In some embodiments, the adjusting the capacitance value of the resonant capacitor and / or the resistance value of the resistor until the load current is equal to the target load current and the LC resonant circuit is determined to be in a resonant state according to the capacitor voltage and the load voltage and then the adjustment is stopped, comprises:

[0046] Adjusting the capacitance value of the resonant capacitor until the capacitor voltage is equal to the load voltage and then stopping the adjustment;

[0047] adjusting the resistance value of the resistor until the load current is equal to the target load current and stopping the adjustment; and

[0048] The capacitance value of the resonant capacitor is adjusted again until the capacitor voltage is equal to the load voltage and then the adjustment is stopped.

[0049] A third aspect of the present application further provides an inductance detection device, which includes the inductance detection circuit described in the first aspect.

[0050] The fourth aspect of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores executable instructions, and when the executable instructions are executed by a processor, the inductance detection method described in the second aspect above is implemented.

[0051] The fifth aspect of the present application further provides an electrical device, which includes the inductance detection device described in the third aspect above, or includes the computer-readable storage medium described in the fourth aspect above.

[0052] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 is a schematic diagram of the topological structure of the inductance detection circuit provided in an embodiment of the present application;

[0054] Figure 2 is a circuit structure diagram of an inductance detection circuit provided in an embodiment of the present application;

[0055] Figure 3 is another circuit structure schematic diagram of the inductance detection circuit provided in an embodiment of the present application;

[0056] Figure 4 is a schematic diagram of the structure of an inductance detection device provided in an embodiment of the present application;

[0057] Figure 5 It is a flow chart of the inductance detection method provided in an embodiment of the present application.

[0058] The following are the descriptions of the reference numerals:

[0059] Inductance detection device 1

[0060] Housing 300

[0061] Inductance detection circuit 100

[0062] Inductor to be measured L

[0063] DC Power Supply 200

[0064] Voltage conversion circuit 10

[0065] The first input terminal 11

[0066] The second input terminal 12

[0067] The first output terminal 13

[0068] The second output terminal 14

[0069] Resistor R

[0070] Resonant capacitor C

[0071] Detection circuit 30

[0072] Controller 20

[0073] The first switch tube T1

[0074] The second switch tube T2

[0075] The first capacitor C1

[0076] The second capacitor C2

[0077] The third switch tube T3

[0078] The fourth switch tube T4

[0079] The fifth switch tube T5

[0080] The sixth switch tube T6

[0081] The third capacitor C3

[0082] The following specific implementation methods will illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0083] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0084] In addition, the terms "first", "second", etc. in the specification of the present invention are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0085] It should be noted that, in the absence of conflict, the features in the embodiments of the present application may be combined with each other.

[0086] See also Figure 1 , Figure 1 1 is a schematic diagram of the topological structure of the inductance detection circuit provided in an embodiment of the present application. The present application provides an inductance detection circuit 100, which is used to detect the inductance of the inductor L to be measured when a target load current of a target frequency flows through the inductor L to be measured. The target frequency can be any pre-selected frequency, for example, 50 Hz, 60 Hz, 100 Hz, etc. The target load current can be any pre-selected current, for example, 1 A, 2 A, 10 A, etc.

[0087] like Figure 1 As shown, the inductance detection circuit 100 includes a voltage conversion circuit 10 , a resistor R, a resonant capacitor C, a detection circuit 30 and a controller 20 .

[0088] The voltage conversion circuit 10 is electrically connected to the DC power supply 200 .

[0089] The resistor R and the inductor L to be measured are both electrically connected to the voltage conversion circuit 10 , and the resistance value of the resistor R is adjustable.

[0090] The resonant capacitor C is electrically connected to the inductor L to be measured to form an LC resonant circuit, and the capacitance value of the resonant capacitor C is adjustable.

[0091] The detection circuit 30 is used to detect the load current flowing through the inductor L to be measured, the capacitor voltage across the resonant capacitor C, and the load voltage. The load voltage is the sum of the voltage across the inductor L to be measured and the voltage across the resistor R.

[0092] The controller 20 is electrically connected to the voltage conversion circuit 10 and the detection circuit 30, and is used to control the voltage conversion circuit 10 to invert the DC voltage provided by the DC power supply 200 into an AC voltage with a frequency of the target frequency, so as to output the AC voltage to the resistor R and the inductor L to be measured through the voltage conversion circuit 10. The controller 20 is also used to determine the inductance of the inductor L to be measured based on the capacitance value of the resonant capacitor C and the target frequency when at least one of the capacitance value of the resonant capacitor C and the resistance value of the resistor R is adjusted, when the load current is equal to the target load current and it is determined that the LC resonant circuit is in a resonant state according to the capacitor voltage and the load voltage.

[0093] The inductance detection circuit 100 provided in the present application controls the voltage conversion circuit 10 through the controller 20 to provide an alternating current with a target frequency to the inductor L to be measured, adjusts the current flowing through the inductor L to be measured to reach the target load current by setting a resistor R with an adjustable resistance value, and achieves a resonant state with the inductor L to be measured at the target frequency by setting a resonant capacitor C with an adjustable capacitance value, and determines the inductance of the inductor L to be measured according to the capacitance value of the resonant capacitor C when the resonant state with the inductor L to be measured reaches the target load current at the target frequency and the target frequency through the controller 20, thereby being able to detect the inductance of the inductor L to be measured at any frequency and any load current, and the measurement circuit is simple and the measurement range is wider.

[0094] In some embodiments, the voltage conversion circuit 10 includes a first input terminal 11, a second input terminal 12, a first output terminal 13, a second output terminal 14, a first branch, and a second branch.

[0095] The first input terminal 11 and the second input terminal 12 are electrically connected to the positive electrode and the negative electrode of the DC power source 200 respectively.

[0096] The resistor R and the inductor L to be measured are connected in series between the first output terminal 13 and the second output terminal 14 .

[0097] The first branch and the second branch are both electrically connected to the first input terminal 11, the second input terminal 12, the first output terminal 13, and the second output terminal 14. The first branch and the second branch are alternately turned on according to the target frequency under the control of the controller 20, so as to invert the DC voltage provided by the DC power supply 200 into an AC voltage with a frequency of the target frequency, and output the AC voltage to the resistor R and the inductor L to be measured.

[0098] Exemplarily, the DC power supply 200 can be a battery or a rectifier circuit, that is, the DC voltage received by the first input terminal 11 and the second input terminal 12 of the voltage conversion circuit 10 can be a DC voltage provided by a battery, or can be a DC voltage output by the rectifier circuit after rectifying the AC voltage.

[0099] Exemplarily, the controller 20 can be composed of an integrated circuit, for example, it can be composed of a single packaged integrated circuit, or it can be composed of multiple integrated circuits packaged with the same function or different functions, including one or more central processing units (CPU), microprocessors (MCU), digital signal processing (DSP) chips, complex programmable logic devices (CPLD) chips, field programmable gate arrays (FPGA) chips, single-chip microcomputers and a combination of various control chips, etc.

[0100] In some embodiments, the inductance detection circuit 100 may further include a display module (not shown), the display module is electrically connected to the controller 20, and the controller 20 is used to control the display module to display the inductance value of the inductor to be measured. Exemplarily, the display module may be a digital tube, or a display device such as an LCD screen or an LED screen.

[0101] The controller 20 can also be used to control the display module to display the load current flowing through the inductor L to be tested, the capacitor voltage across the resonant capacitor C, and the load voltage detected by the detection circuit 30. In this way, in one embodiment, the resistance value of the resistor R and / or the capacitance value of the resonant capacitor C can be adjusted by the operator. Specifically, the resistor R changes its own resistance value in response to the operator's resistance adjustment operation, and the resonant capacitor C also changes its own capacitance value in response to the operator's capacitance adjustment operation. During the adjustment process, the operator can change the resistance adjustment operation performed on the resistor R according to these detection results, so that the load current reaches the target load current, and change the capacitance adjustment operation performed on the resonant capacitor C, so that the LC resonant circuit reaches a resonant state. Exemplarily, when the load current flowing through the inductor L to be measured is higher than the target load current, the operator increases the resistance value of the resistor R; when the load current flowing through the inductor L to be measured is lower than the target load current, the operator decreases the resistance value of the resistor R; when the load current flowing through the inductor L to be measured is equal to the target load current, the operator stops adjusting the resistance value of the resistor R.

[0102] In some embodiments, the inductance detection circuit 100 may further include an input module (not shown), the input module is electrically connected to the controller 20, and the controller 20 may obtain the target frequency and the target load current through the input module. Exemplarily, the input module may include a keyboard, a button, a microphone, a touch screen, etc. Thus, in one embodiment, the controller 20 may adjust the resistance value of the resistor R and / or adjust the capacitance value of the resonant capacitor C. Specifically, the controller 20 obtains the target frequency and the target load current through the input module, thereby controlling the voltage conversion circuit 10 to invert the DC voltage provided by the DC power supply 200 into an AC voltage with a frequency of the target frequency, and adjusts the resistance value of the resistor R and / or adjusts the capacitance value of the resonant capacitor C according to the load current flowing through the inductance L to be measured detected by the detection circuit 30, the capacitor voltage across the resonant capacitor C, and the load voltage, so that the load current reaches the target load current, and the LC resonant circuit reaches a resonant state.

[0103] See also Figure 2 , Figure 2 Schematic diagram of a circuit structure of an inductance detection circuit provided in an embodiment of the present application. Figure 2 As shown, in some embodiments, the first branch includes a first switch tube T1 and a second capacitor C2. The second branch includes a second switch tube T2 and a first capacitor C1.

[0104] The first switch tube T1 is electrically connected between the first input terminal 11 and the first output terminal 13 .

[0105] The second switch tube T2 is electrically connected between the first output terminal 13 and the second input terminal 12 .

[0106] The first capacitor C1 is electrically connected between the first input terminal 11 and the second output terminal 14 .

[0107] The second capacitor C2 is electrically connected between the second output terminal 14 and the second input terminal 12 .

[0108] The resonant capacitor C includes a first capacitor C1 and a second capacitor C2 in the voltage conversion circuit 10 , and the capacitance value of the first capacitor C1 and the capacitance value of the second capacitor C2 are both adjustable.

[0109] Furthermore, the detection circuit 30 is specifically configured to detect the load current, the first voltage across the first capacitor C1 , the second voltage across the second capacitor C2 , and the load voltage.

[0110] The controller 20 is electrically connected to the first switch tube T1 and the second switch tube T2, and is used to control the first switch tube T1 and the second switch tube T2 to be turned on alternately according to the target frequency, so as to invert the DC voltage provided by the DC power supply 200 into an AC voltage with a frequency of the target frequency. In the process of adjusting at least one of the capacitance value of the first capacitor C1, the capacitance value of the second capacitor C2 and the resistance value of the resistor R, the controller 20 is specifically used to determine the inductance of the inductor L to be measured based on the capacitance value of the first capacitor C1, the capacitance value of the second capacitor C2 and the target frequency when the load current is equal to the target load current and the inductor L to be measured and the first capacitor C1 and the second capacitor C2 are determined to be in a resonant state under the target load current according to the first voltage, the second voltage and the load voltage.

[0111] Among them, the inductor L to be measured and the first capacitor C1 and the second capacitor C2 are in a resonant state under the target load current, which means that the load current flowing through the inductor L to be measured is equal to the target load current, and the frequency of the load current is the target frequency, and the inductor L to be measured and the first capacitor C1 and the second capacitor C2 are in a resonant state.

[0112] During operation, when the first switch tube T1 is turned on and the second switch tube T2 is turned off, the current flows out from the positive electrode of the DC power supply 200, passes through the first switch tube T1, the resistor R, the inductor L to be measured and the second capacitor C2 in sequence, and returns to the negative electrode of the DC power supply 200; when the first switch tube T1 is turned off and the second switch tube T2 is turned on, the current flows out from the positive electrode of the DC power supply 200, passes through the first capacitor C1, the inductor L to be measured, the resistor R and the second switch tube T2 in sequence, and returns to the negative electrode of the DC power supply 200.

[0113] Furthermore, the controller 20 is specifically used to determine that the inductor L to be measured and the first capacitor C1 and the second capacitor C2 are in a resonant state under the target load current when the effective value of the first voltage, the effective value of the second voltage and the effective value of the load voltage are all equal and the load current is equal to the target load current.

[0114] Specifically, in one embodiment, the controller 20 is specifically used to control the voltage conversion circuit 10 to invert the DC voltage provided by the DC power supply 200 into an AC voltage with a frequency of the target frequency in response to the received target frequency. The controller 20 also controls the capacitance value of the resonant capacitor C in response to the received target load current until the effective value of the first voltage, the effective value of the second voltage, and the effective value of the load voltage are all equal, and then controls the resistance value of the resistor R to be adjusted until the load current is equal to the target load current, and then controls the capacitance value of the resonant capacitor C to be adjusted again until the effective value of the first voltage, the effective value of the second voltage, and the effective value of the load voltage are all equal again, and then determines that the inductor L to be measured and the first capacitor C1 and the second capacitor C2 are in a resonant state under the target load current.

[0115] Further, the controller 20 is specifically used to determine the inductance of the inductor L to be measured according to a first preset resonance formula based on the capacitance value of the first capacitor C1, the capacitance value of the second capacitor C2 and the target frequency when it is determined that the inductor L to be measured and the first capacitor C1 and the second capacitor C2 are in a resonant state under the target load current.

[0116] Wherein, the first preset resonance formula is L=1 / (4*π 2 *f 2*(C1+C2)), wherein C1 is the capacitance value of the first capacitor C1 when the LC resonant circuit is in the resonant state at the target load current, C2 is the capacitance value of the second capacitor C2 when the LC resonant circuit is in the resonant state at the target load current, and f is the target frequency.

[0117] Further, the controller 20 is specifically used to output a first control signal and a second control signal, both of which have the target frequency, to the first switch tube T1 and the second switch tube T2, respectively, so as to control the first switch tube T1 and the second switch tube T2 to be alternately turned on according to the target frequency. The duty cycle of the first control signal is equal to the duty cycle of the second control signal and is less than or equal to 50%, and the phase of the first control signal is 180 degrees different from the phase of the second control signal.

[0118] Among them, the first control signal and the second control signal are both PWM signals, so that the frequency of the alternating current output by the voltage conversion circuit 10 is determined by the frequencies of the first control signal and the second control signal, that is, by changing the frequencies of the first control signal and the second control signal, the frequency of the load current can be steplessly adjusted.

[0119] See also Figure 3 , Figure 3 FIG. 1 is another circuit structure diagram of the inductance detection circuit provided in the embodiment of the present application. Figure 3 As shown, in some embodiments, the first branch includes a third switch tube T3 and a sixth switch tube T6, and the second branch includes a fourth switch tube T4 and a fifth switch tube T5.

[0120] The third switch tube T3 is electrically connected between the first input terminal 11 and the first output terminal 13 .

[0121] The fourth switch tube T4 is electrically connected between the first output terminal 13 and the second input terminal 12 .

[0122] The fifth switch tube T5 is electrically connected between the first input terminal 11 and the second output terminal 14 .

[0123] The sixth switch tube T6 is electrically connected between the second output terminal 14 and the second input terminal 12 .

[0124] The resonant capacitor C includes a third capacitor C3, the third capacitor C3, the resistor R, and the inductor L to be measured are connected in series between the first output terminal 13 and the second output terminal 14, and the capacitance value of the third capacitor C3 is adjustable.

[0125] Furthermore, the detection circuit 30 is specifically used to detect the load current, the third voltage across the third capacitor C3, and the load voltage.

[0126] The controller 20 is electrically connected to the third switch tube T3, the fourth switch tube T4, the fifth switch tube T5 and the sixth switch tube T6, and is used to control the third switch tube T3 and the fourth switch tube T4 to be alternately turned on according to the target frequency, and to control the fifth switch tube T5 and the sixth switch tube T6 to be alternately turned on according to the target frequency, so as to invert the DC voltage provided by the DC power supply 200 into an AC voltage with a frequency of the target frequency. Among them, the on-off state of the third switch tube T3 and the sixth switch tube T6 is the same, and the on-off state of the fourth switch tube T4 and the fifth switch tube T5 is the same. In the process of adjusting at least one of the capacitance value of the third capacitor C3 and the resistance value of the resistor R, the controller 20 is specifically used to determine the inductance of the inductor L to be measured based on the capacitance value of the third capacitor C3 and the target frequency when the load current is equal to the target load current and the LC resonant circuit is determined to be in a resonant state under the target load current according to the third voltage and the load voltage.

[0127] During operation, when the third switch tube T3 and the sixth switch tube T6 are both turned on, and the fourth switch tube T4 and the fifth switch tube T5 are both turned off, the current flows out from the positive electrode of the DC power supply 200, passes through the third switch tube T3, the resistor R, the inductor L to be measured, the third capacitor C3 and the sixth switch tube T6 in sequence, and returns to the negative electrode of the DC power supply 200; when the third switch tube T3 and the sixth switch tube T6 are both turned off, and the fourth switch tube T4 and the fifth switch tube T5 are both turned on, the current flows out from the positive electrode of the DC power supply 200, passes through the fifth switch tube T5, the third capacitor C3, the inductor L to be measured, the resistor R and the fourth switch tube T4 in sequence, and returns to the negative electrode of the DC power supply 200.

[0128] It should be noted that the first capacitor C1, the second capacitor C2 and the third capacitor C3 may be a single capacitor, or a capacitor group consisting of a plurality of capacitors connected in series and / or in parallel.

[0129] Among them, Figure 3 Compared with the voltage conversion circuit 10 shown, Figure 2 The voltage conversion circuit 10 shown has fewer switch tubes, lower cost, and lower switching loss.

[0130] Furthermore, the controller 20 is specifically configured to determine that the LC resonant circuit is in a resonant state under a target load current when the effective value of the third voltage is equal to the effective value of the load voltage and the load current is equal to the target load current.

[0131] Further, the controller 20 is specifically used to determine the inductance of the inductor L to be measured according to a second preset resonance formula based on the capacitance value of the third capacitor C3 and the target frequency. Wherein, the second preset resonance formula is L=1 / (4*π 2 *f 2 *C3), wherein C3 is the capacitance value of the third capacitor C3 when the LC resonant circuit is in a resonant state under a target load current, and f is the target frequency.

[0132] Further, the controller 20 is specifically used to output a third control signal having a frequency of the target frequency to the third switch tube T3 and the sixth switch tube T6, and output a fourth control signal having a frequency of the target frequency to the fourth switch tube T4 and the fifth switch tube T5, so as to control the third switch tube T3 and the fourth switch tube T4 to be turned on alternately according to the target frequency, and control the fifth switch tube T5 and the sixth switch tube T6 to be turned on alternately according to the target frequency. The duty cycle of the third control signal is equal to the duty cycle of the fourth control signal and is less than or equal to 50%, and the phase of the third control signal is 180 degrees different from the phase of the fourth control signal.

[0133] Exemplarily, the first switch tube T1 to the sixth switch tube T6 can be made of at least one of silicon carbide, thyristor, metal-oxide-semiconductor field-effect transistor (MOSFET), insulated gate bipolar transistor (IGBT), bipolar junction transistor (BJT) and insulated gate field effect transistor (MOS).

[0134] See also Figure 4 , Figure 4 1 is a schematic diagram of the structure of the inductance detection device provided in the embodiment of the present application. Based on the same inventive concept, the present application also provides an inductance detection device 1, and the inductance detection device 1 includes the inductance detection circuit 100 described in any of the above embodiments.

[0135] In some embodiments, the inductance detection device 1 further includes a housing 300 , and the inductance detection circuit 100 is disposed in the housing 300 .

[0136] See also Figure 5 , Figure 5 1 is a flow chart of an inductance detection method provided in an embodiment of the present application. Based on the same inventive concept, the present application also provides an inductance detection method, which is applied to the inductance detection circuit 100 described in any of the above embodiments.

[0137] like Figure 5 As shown, the inductance detection method includes the following steps:

[0138] Step S1, controlling the voltage conversion circuit 10 to invert the DC voltage provided by the DC power supply 200 into an AC voltage with a target frequency, so as to output the AC voltage to the resistor R and the inductor L to be measured through the voltage conversion circuit 10;

[0139] Step S2, adjusting the capacitance value of the resonant capacitor C and / or adjusting the resistance value of the resistor R until the load current is equal to the target load current and the LC resonant circuit is determined to be in a resonant state according to the capacitor voltage and the load voltage, and then stopping the adjustment;

[0140] Step S3, obtaining a capacitance value of the resonant capacitor C when the LC resonant circuit is in a resonant state under the target load current; and

[0141] Step S4, determining the inductance of the inductor to be measured L based on the capacitance value of the resonant capacitor C and the target frequency.

[0142] In some embodiments, the adjusting the capacitance value of the resonant capacitor C and / or the resistance value of the resistor R, and stopping the adjustment when the load current is equal to the target load current and it is determined according to the capacitor voltage and the load voltage that the LC resonant circuit is in a resonant state, includes:

[0143] Adjusting the capacitance value of the resonant capacitor C until the capacitor voltage is equal to the load voltage and then stopping the adjustment;

[0144] adjusting the resistance value of the resistor R until the load current is equal to the target load current and then stopping the adjustment; and,

[0145] The capacitance value of the resonant capacitor C is adjusted again until the capacitor voltage is equal to the load voltage and then the adjustment is stopped.

[0146] In some embodiments, the voltage conversion circuit 10 includes a first input terminal 11, a second input terminal 12, a first output terminal 13, a second output terminal 14, a first branch, and a second branch.

[0147] The first input terminal 11 and the second input terminal 12 are electrically connected to the positive electrode and the negative electrode of the DC power source 200 respectively.

[0148] The resistor R and the inductor L to be measured are connected in series between the first output terminal 13 and the second output terminal 14 .

[0149] The first branch and the second branch are both electrically connected to the first input terminal 11, the second input terminal 12, the first output terminal 13, and the second output terminal 14. The first branch and the second branch are alternately turned on according to the target frequency under the control of the controller 20, so as to invert the DC voltage provided by the DC power supply 200 into an AC voltage with a frequency of the target frequency, and output the AC voltage to the resistor R and the inductor L to be measured.

[0150] In some embodiments, the first branch includes a first switch tube T1 and a second capacitor C2. The second branch includes a second switch tube T2 and a first capacitor C1.

[0151] The first switch tube T1 is electrically connected between the first input terminal 11 and the first output terminal 13 .

[0152] The second switch tube T2 is electrically connected between the first output terminal 13 and the second input terminal 12 .

[0153] The first capacitor C1 is electrically connected between the first input terminal 11 and the second output terminal 14 .

[0154] The second capacitor C2 is electrically connected between the second output terminal 14 and the second input terminal 12 .

[0155] The resonant capacitor C includes the first capacitor C1 and the second capacitor C2, and the capacitance value of the first capacitor C1 and the capacitance value of the second capacitor C2 are both adjustable.

[0156] Further, the adjusting the capacitance value of the resonant capacitor C until the capacitor voltage is equal to the load voltage and the adjustment is stopped, including:

[0157] The capacitance values ​​of the first capacitor C1 and the second capacitor C2 are adjusted until the effective value of the first voltage, the effective value of the second voltage, and the effective value of the load voltage are all equal, and then the adjustment is stopped.

[0158] The step of adjusting the capacitance value of the resonant capacitor C again until the capacitor voltage is equal to the load voltage and then stopping the adjustment includes:

[0159] The capacitance values ​​of the first capacitor C1 and the second capacitor C2 are adjusted again until the effective value of the first voltage, the effective value of the second voltage, and the effective value of the load voltage are equal again, and then the adjustment is stopped.

[0160] In some embodiments, the first branch includes a third switch tube T3 and a sixth switch tube T6, and the second branch includes a fourth switch tube T4 and a fifth switch tube T5.

[0161] The third switch tube T3 is electrically connected between the first input terminal 11 and the first output terminal 13 .

[0162] The fourth switch tube T4 is electrically connected between the first output terminal 13 and the second input terminal 12 .

[0163] The fifth switch tube T5 is electrically connected between the first input terminal 11 and the second output terminal 14 .

[0164] The sixth switch tube T6 is electrically connected between the second output terminal 14 and the second input terminal 12 .

[0165] The resonant capacitor C includes a third capacitor C3, the third capacitor C3, the resistor R, and the inductor L to be measured are connected in series between the first output terminal 13 and the second output terminal 14, and the capacitance value of the third capacitor C3 is adjustable.

[0166] Further, the adjusting the capacitance value of the resonant capacitor C until the capacitor voltage is equal to the load voltage and the adjustment is stopped, including:

[0167] The capacitance value of the third capacitor C3 is adjusted until the effective value of the third voltage is equal to the effective value of the load voltage, and then the adjustment is stopped.

[0168] The step of adjusting the capacitance value of the resonant capacitor C again until the capacitor voltage is equal to the load voltage and then stopping the adjustment includes:

[0169] The capacitance value of the third capacitor C3 is adjusted again until the effective value of the third voltage and the effective value of the load voltage are equal again, and then the adjustment is stopped.

[0170] Based on the same inventive concept, the present application also provides a computer-readable storage medium, wherein the computer-readable storage medium stores executable instructions, and when the executable instructions are executed by a processor, the above-mentioned inductance detection method is implemented.

[0171] Based on the same inventive concept, the present application also provides an electrical device, which includes the inductance detection device 1 described in the above embodiment, or includes the computer-readable storage medium described in the above embodiment.

[0172] Exemplarily, the electrical equipment includes cars, ships, etc.

[0173] The computer storage medium of the embodiment of the present application can adopt any combination of one or more computer-readable media. Computer-readable media can be computer-readable signal media or computer-readable storage media. Computer-readable storage media can be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination of the above. More specific examples (non-exhaustive lists) of computer-readable storage media include: electrical connections with one or more wires, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In this document, computer-readable storage media can be any tangible medium containing or storing programs, which can be used by instruction execution systems, devices or devices or used in combination with them.

[0174] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0175] The program code embodied on the computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0176] Computer program code for performing the operations of the present invention may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as C or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer or may be connected to an external computer (e.g., via the Internet using an Internet service provider) through any type of network, including a local area network (LAN) or a wide area network (WAN).

[0177] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. An inductance detection circuit, characterized in that: The inductance detection circuit is used to detect the inductance of the inductor to be tested when a target load current of a target frequency flows through the inductor, and the inductance detection circuit includes: A voltage conversion circuit is electrically connected to the DC power supply; A resistor, which is electrically connected to the voltage conversion circuit together with the inductor to be measured, and the resistance value of the resistor is adjustable; A resonant capacitor, electrically connected to the inductor to be measured to form an LC resonant circuit, wherein the capacitance value of the resonant capacitor is adjustable; A detection circuit, used to detect the load current flowing through the inductor to be measured, the capacitor voltage across the resonant capacitor, and the load voltage; wherein the load voltage is the sum of the voltage across the inductor to be measured and the voltage across the resistor; and a controller, electrically connected to the voltage conversion circuit and the detection circuit, and configured to control the voltage conversion circuit to invert the DC voltage provided by the DC power supply into an AC voltage having a frequency of the target frequency, thereby outputting the AC voltage to the resistor and the inductor to be measured through the voltage conversion circuit; The controller is also used to determine the inductance of the inductor to be measured based on the capacitance value of the resonant capacitor and the target frequency when the load current is equal to the target load current and the LC resonant circuit is determined to be in a resonant state based on the capacitor voltage and the load voltage during the process of adjusting at least one of the capacitance value of the resonant capacitor and the resistance value of the resistor.

2. The inductance detection circuit according to claim 1, characterized in that: The voltage conversion circuit comprises: a first input terminal and a second input terminal, wherein the first input terminal is electrically connected to the positive electrode of the DC power supply, and the second input terminal is electrically connected to the negative electrode of the DC power supply; A first output terminal and a second output terminal, wherein the resistor and the inductor to be measured are connected in series between the first output terminal and the second output terminal; The first branch and the second branch are both electrically connected to the first input terminal, the second input terminal, the first output terminal and the second output terminal; wherein the first branch and the second branch are alternately turned on according to the target frequency under the control of the controller, thereby inverting the DC voltage provided by the DC power supply into an AC voltage with a frequency of the target frequency, and outputting the AC voltage to the resistor and the inductor to be measured.

3. The inductance detection circuit according to claim 2, characterized in that: The first branch comprises: A first switch tube is electrically connected between the first input terminal and the first output terminal; and A second capacitor, electrically connected between the second output terminal and the second input terminal; The second branch comprises: A second switch tube is electrically connected between the first output terminal and the second input terminal; and A first capacitor, electrically connected between the first input terminal and the second output terminal; The resonant capacitor includes a first capacitor and a second capacitor in the voltage conversion circuit, and the capacitance value of the first capacitor and the capacitance value of the second capacitor are both adjustable.

4. The inductance detection circuit according to claim 3, characterized in that: The detection circuit is specifically used to detect the load current, the first voltage across the first capacitor, the second voltage across the second capacitor, and the load voltage; The controller is electrically connected to the first switch tube and the second switch tube, and is used to control the first switch tube and the second switch tube to be alternately turned on according to the target frequency, so as to invert the DC voltage provided by the DC power supply into an AC voltage with a frequency of the target frequency; in the process of adjusting at least one of the capacitance value of the first capacitor, the capacitance value of the second capacitor and the resistance value of the resistor, the controller is specifically used to determine the inductance of the inductor to be measured based on the capacitance value of the first capacitor, the capacitance value of the second capacitor and the target frequency when the load current is equal to the target load current and it is determined according to the first voltage, the second voltage and the load voltage that the LC resonant circuit is in a resonant state under the target load current.

5. The inductance detection circuit according to claim 4, characterized in that: The controller is specifically used to determine that the LC resonant circuit is in a resonant state under a target load current when the effective value of the first voltage, the effective value of the second voltage, and the effective value of the load voltage are all equal, and the load current is equal to the target load current.

6. The inductance detection circuit according to claim 4, characterized in that: The controller is specifically used to determine the inductance of the inductor to be measured according to a first preset resonance formula based on the capacitance value of the first capacitor, the capacitance value of the second capacitor and the target frequency; wherein the first preset resonance formula is L=1 / (4*π 2 *f 2 *(C1+C2)), wherein C1 is the capacitance value of the first capacitor when the LC resonant circuit is in the resonant state at the target load current, C2 is the capacitance value of the second capacitor when the LC resonant circuit is in the resonant state at the target load current, and f is the target frequency.

7. The inductance detection circuit according to claim 4, characterized in that: The controller is specifically used to output a first control signal and a second control signal, both of which have the target frequency, to the first switch tube and the second switch tube, respectively, so as to control the first switch tube and the second switch tube to be alternately turned on according to the target frequency; wherein the duty cycle of the first control signal is equal to the duty cycle of the second control signal and is less than or equal to 50%, and the phase of the first control signal differs by 180 degrees from the phase of the second control signal.

8. The inductance detection circuit according to claim 2, characterized in that: The first branch comprises: A third switch tube is electrically connected between the first input terminal and the first output terminal; and a sixth switch tube, electrically connected between the second output terminal and the second input terminal; The second branch comprises: a fourth switch tube, electrically connected between the first output terminal and the second input terminal; and a fifth switch tube, electrically connected between the first input terminal and the second output terminal; The resonant capacitor includes a third capacitor, and the third capacitor, the resistor, and the inductor to be measured are connected in series between the first output terminal and the second output terminal, and the capacitance value of the third capacitor is adjustable.

9. The inductance detection circuit according to claim 8, characterized in that: The detection circuit is specifically used to detect the load current, the third voltage across the third capacitor, and the load voltage; The controller is electrically connected to the third switch tube, the fourth switch tube, the fifth switch tube and the sixth switch tube, and is used to control the third switch tube and the fourth switch tube to be alternately turned on according to the target frequency, and control the fifth switch tube and the sixth switch tube to be alternately turned on according to the target frequency, so as to invert the DC voltage provided by the DC power supply into an AC voltage with a frequency of the target frequency; wherein the on-off state of the third switch tube and the sixth switch tube is the same, and the on-off state of the fourth switch tube and the fifth switch tube is the same; in the process of adjusting at least one of the capacitance value of the third capacitor and the resistance value of the resistor, the controller is specifically used to determine the inductance of the inductor to be measured based on the capacitance value of the third capacitor and the target frequency when the load current is equal to the target load current and it is determined according to the third voltage and the load voltage that the LC resonant circuit is in a resonant state under the target load current.

10. The inductance detection circuit according to claim 9, characterized in that: The controller is specifically used to determine that the LC resonant circuit is in a resonant state under the target load current when the effective value of the third voltage is equal to the effective value of the load voltage and the load current is equal to the target load current.

11. The inductance detection circuit according to claim 9, characterized in that: The controller is specifically used to determine the inductance of the inductor to be measured according to a second preset resonance formula based on the capacitance value of the third capacitor and the target frequency; wherein the second preset resonance formula is L=1 / (4*π 2 *f 2 *C3), wherein C3 is the capacitance value of the third capacitor when the LC resonant circuit is in a resonant state under a target load current, and f is the target frequency.

12. The inductance detection circuit according to claim 9, characterized in that: The controller is specifically used to output a third control signal with a frequency of the target frequency to the third switch tube and the sixth switch tube, and to output a fourth control signal with a frequency of the target frequency to the fourth switch tube and the fifth switch tube, so as to control the third switch tube and the fourth switch tube to be alternately turned on according to the target frequency, and to control the fifth switch tube and the sixth switch tube to be alternately turned on according to the target frequency; wherein the duty cycle of the third control signal is equal to the duty cycle of the fourth control signal and is less than or equal to 50%, and the phase of the third control signal differs by 180 degrees from the phase of the fourth control signal.

13. An inductance detection method, characterized in that: The inductance detection method is applied to the inductance detection circuit according to any one of claims 1 to 12, and the inductance detection method includes: Controlling the voltage conversion circuit to invert the DC voltage provided by the DC power supply into an AC voltage with a target frequency, thereby outputting the AC voltage to the resistor and the inductor to be measured through the voltage conversion circuit; adjusting the capacitance value of the resonant capacitor and / or adjusting the resistance value of the resistor until the load current is equal to the target load current and the LC resonant circuit is determined to be in a resonant state according to the capacitor voltage and the load voltage, and then stopping the adjustment; acquiring a capacitance value of the resonant capacitor when the LC resonant circuit is in a resonant state under the target load current; and The inductance of the inductor to be measured is determined based on the capacitance value of the resonant capacitor and the target frequency.

14. The inductance detection method according to claim 13, characterized in that: The adjusting the capacitance value of the resonant capacitor and / or the resistance value of the resistor until the load current is equal to the target load current and the LC resonant circuit is determined to be in a resonant state according to the capacitor voltage and the load voltage and then the adjustment is stopped, comprising: Adjusting the capacitance value of the resonant capacitor until the capacitor voltage is equal to the load voltage and then stopping the adjustment; adjusting the resistance value of the resistor until the load current is equal to the target load current and stopping the adjustment; and The capacitance value of the resonant capacitor is adjusted again until the capacitor voltage is equal to the load voltage and then the adjustment is stopped.

15. An inductance detection device, characterized in that: The invention comprises an inductance detection circuit as claimed in any one of claims 1 to 12.

16. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores executable instructions, and when the executable instructions are executed by the processor, the inductance detection method according to claim 13 or 14 is implemented.

17. An electrical equipment, characterized in that: Includes the inductance detection device as claimed in claim 15, or includes the computer-readable storage medium as claimed in claim 16.

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