JP2017096733A - Measurement device and measurement method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure a capacitance value, etc., while a defined voltage is accurately applied to a capacitor component, etc., to be measured.SOLUTION: A measurement device of the present invention comprises: a voltage generation unit 2 for generating an AC voltage Vm for measurement that is applied to an electronic component 11; a voltage detection unit 3 for detecting an end-to-end voltage V1 developed between both ends of the electronic component 11 due to that a measurement current Im flows when the AC voltage Vm for measurement is applied; a current detection unit 4 for detecting the measurement current Im; and a processing unit 5 for executing a measurement process to measure the capacitance Value C of a capacitor as the electronic component 11 on the basis of the frequencies f of the end-to-end voltage V1, measurement current Im, and AC voltage Vm for measurement. The processing unit 5 executes a phase difference detection process to detect a phase difference θ between the end-to-end voltage V1 and the measurement current Im, and on the occasion of the measurement process, causes the voltage generation unit 2 to generate the AC voltage Vm for measurement with a corrected defined voltage value Vrc that is a defined voltage value Vr, used when measuring the capacitance value C, that is multiplied by 1/sinθ.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a measuring apparatus and a measuring method for measuring impedance of a measuring object such as a capacitor and an inductor.

  As this type of measuring apparatus, the applicant of the present application has already proposed the measuring apparatus disclosed in Patent Document 1 below. This measuring device is a capacitance measuring device that measures a capacitance of a capacitor (capacitor) as a measurement target, and includes an oscillator (AC signal supply unit) capable of supplying a measuring AC signal, and a measuring AC signal. An amplifying circuit (current-voltage converter) that converts the current flowing through the measurement target at the time of application, a voltage detection unit that detects a voltage across the measurement target when the measurement AC signal is applied; A control unit is provided that measures the impedance and capacitance of the measurement object based on the frequency of the AC signal for measurement, the waveform of the voltage that has been converted from current to voltage by the current-voltage conversion unit, and the waveform of the voltage between both ends.

  By the way, depending on the object to be measured, there is a voltage dependency (current flowing depending on the voltage value of the voltage applied at the time of measurement, and the property that the measured impedance or capacitance changes) (for example, a multilayer ceramic capacitor). When measuring such a measurement object, it is necessary to accurately apply a specified constant voltage (for example, a constant voltage specified by a standard such as JIS). For this reason, when measuring this type of measurement object, for example, the voltage between both ends detected by the voltage detection unit is controlled by the control unit controlling the amplitude of the measurement AC signal supplied from the AC signal supply unit. Is set to the specified constant voltage.

JP 2007-121125 A (page 4-6, FIG. 1)

  However, there are the following problems to be improved in the measuring apparatus adopting the configuration in which the voltage between both ends is made constant as described above. That is, in this measuring device, the voltage between both ends detected by the voltage detector is set to a specified constant voltage, but when the measuring device measures the impedance by the two-terminal method, the voltage detector Since the probe to be connected and the probe connected to the AC signal supply unit are common, the contact resistance between this probe and the terminal to be measured and the wiring resistance of this probe (in series with respect to the measurement object) The voltage drop across the resistor) is included in the voltage between both ends. In addition, when the measuring device measures the impedance by either the two-terminal method or the four-terminal method, when the measurement target is a capacitor, not only the capacitor component but also the resistance component exists in series with the capacitor component. When the measurement target is an inductor, not only the inductor component but also the resistance component exists in series with this inductor component, so the voltage drop at this resistance component is included in the voltage across the two ends . In other words, the voltage between both ends detected by the voltage detection unit is the resistance applied in series with the voltage applied to the capacitor component or the inductor component (hereinafter referred to as capacitor component) and the capacitor component. This is the combined voltage of the voltage drop in the component (the voltage applied to this resistance component). Therefore, it is difficult for this measuring device to measure the capacitance value and the inductance value in a state where a specified voltage is accurately applied to the capacitor component and inductor component to be measured, and there is a problem that this should be improved. doing.

  The present invention has been made in view of such a problem, and mainly provides a measuring apparatus and a measuring method capable of measuring a capacitance value or the like in a state where a specified voltage is accurately applied to a capacitor component or the like to be measured. Objective.

  In order to achieve the above object, the measuring device according to claim 1 is configured such that a measuring current flows when the measuring AC voltage is applied to the measuring object, and a measuring current flows when the measuring AC voltage is applied. Based on the voltage detection unit for detecting the voltage between both ends generated between both ends of the measurement object, the current detection unit for detecting the measurement current, the voltage between the both ends, the measurement current, and the frequency of the AC voltage for measurement, A measuring unit including a processing unit that performs a measurement process for measuring a capacitance value of a capacitor as the measurement target, wherein the processing unit includes a phase difference θ between the voltage between both ends and the measurement current. When the phase difference detection process for detecting the phase difference is executed and the measurement process is executed, the voltage value of the AC voltage for measurement when the capacitance value is measured is defined in advance. The pressure value at 1 / sin [theta multiplied by the correction specified voltage to generate the measuring AC voltage to the voltage generator.

  In addition, the measuring apparatus according to claim 2 includes a voltage generator that generates an AC voltage for measurement to be applied to the measurement target, and a measurement current that flows when the AC voltage for measurement is applied. Based on the voltage detection unit for detecting the voltage between both ends generated between, the current detection unit for detecting the measurement current, the frequency between the both end voltage, the measurement current and the AC voltage for measurement, as the measurement object And a processing unit that executes a measurement process for measuring an inductance value of the inductor of the inductor, wherein the processing unit detects a phase difference θ between the voltage between both ends and the measurement current. When the phase difference detection process is performed and the measurement process is performed, a specified voltage value defined in advance as the voltage value of the AC voltage for measurement when the inductance value is measured is 1 / s. In nθ multiplied by the correction specified voltage to generate the measuring AC voltage to the voltage generator.

  In addition, the measuring method according to claim 3 is generated between both ends of the measuring object by applying a measuring AC voltage to the measuring object and a measuring current flowing when the measuring AC voltage is applied. A voltage detection step for detecting a voltage between both ends, a current detection step for detecting the measurement current, and a capacitance of the capacitor as the measurement object based on the frequency between the both-end voltage, the measurement current, and the AC voltage for measurement. A measurement step of measuring a value, wherein a phase difference detection step of detecting a phase difference θ between the voltage between both ends and the measurement current is executed, and when the measurement step is executed In the applying step, a specified voltage value that is specified in advance as a voltage value of the AC voltage for measurement when the capacitance value is measured. / Applying an AC voltage for the measurement by sinθ multiplied by the correction specified voltage.

  Further, the measurement method according to claim 4 is generated between both ends of the measurement object by applying an application step of applying the measurement AC voltage to the measurement object and a measurement current flowing when the measurement AC voltage is applied. A voltage detecting step for detecting a voltage between both ends, a current detecting step for detecting the measurement current, and an inductance of the inductor as the measurement object based on the frequency between the both ends voltage, the measurement current, and the AC voltage for measurement. A measurement step of measuring a value, wherein a phase difference detection step of detecting a phase difference θ between the voltage between both ends and the measurement current is executed, and when the measurement step is executed Is a predetermined voltage value that is previously defined as the voltage value of the AC voltage for measurement when the inductance value is measured in the applying step. / Applying an AC voltage for the measurement by sinθ multiplied by the correction specified voltage.

  In the measurement apparatus according to claim 1 and the measurement method according to claim 3, a phase difference detection process (phase difference detection step) for detecting a phase difference θ between the voltage between both ends and the measurement current is executed, and the measurement process ( When the measurement step) is executed, a corrected specified voltage value obtained by multiplying the specified voltage value previously defined as the voltage value of the AC voltage for measurement when measuring the capacitance value of the capacitor to be measured by 1 / sin θ times. The voltage generator is caused to generate an AC voltage for measurement.

  Therefore, according to this measuring apparatus and measuring method, the capacitance value can be measured in a state where the voltage value of the voltage actually applied across the capacitor component of the capacitor to be measured is accurately set to the specified voltage value. it can.

  In the measurement apparatus according to claim 2 and the measurement method according to claim 4, a phase difference detection process (phase difference detection step) for detecting a phase difference θ between the voltage between both ends and the measurement current is executed, and the measurement process ( (Measurement step) is performed with a corrected specified voltage value obtained by multiplying a specified voltage value previously defined as a voltage value of the AC voltage for measurement when measuring the inductance value of the inductor to be measured by 1 / sin θ. The voltage generator is caused to generate an AC voltage for measurement.

  Therefore, according to this measuring apparatus and measuring method, it is possible to measure the inductance value in a state where the voltage value of the voltage actually applied between both ends of the inductor component of the inductor to be measured is accurately set to the specified voltage value. it can.

1 is a configuration diagram of a measuring device 1.

  Hereinafter, embodiments of a measurement apparatus and a measurement method will be described with reference to the accompanying drawings.

  As shown in FIG. 1, the measurement apparatus 1 as an example of the measurement apparatus includes, as an example, a voltage generation unit 2, a voltage detection unit 3, a current detection unit 4, a processing unit 5, a storage unit 6, and an output unit 7. A characteristic value of the electronic component 11 as a measurement target is measured. The electronic component 11 to be measured includes a capacitor and an inductor. When the capacitor is the electronic component 11, the capacitance value is measured as a characteristic value, and when the inductor is the electronic component 11, the inductance value is measured as the characteristic value. Hereinafter, an example in which the capacitor is the electronic component 11 and the capacitance value C is measured as a characteristic value will be described.

  As an example, the voltage generator 2 is composed of an AC voltage generator whose amplitude can be arbitrarily set, and generates an AC voltage having a constant frequency f as a measurement AC voltage Vm with a set amplitude, not shown. Output from between a pair of output terminals. The voltage generator 2 generates and outputs the measurement AC voltage Vm with the amplitude indicated by the voltage setting data Ds input from the outside. In the following description, in order to facilitate understanding of the invention, the amplitude (voltage value) of the measurement AC voltage Vm is also denoted by Vm. The voltage generator 2 applies the measurement AC voltage Vm between the terminals 11a and 11b of the electronic component 11 (capacitor) via a pair of voltage application probes PL1 and PL2 connected to the output terminals.

  The voltage detection unit 3 includes a pair of voltage detection terminals (not shown) connected to the corresponding probe PL of the pair of voltage application probes PL1 and PL2, and via the pair of voltage application probes PL1 and PL2. It is connected to each terminal 11a, 11b of the component 11. With this configuration, the voltage detection unit 3 has both ends that are AC voltages generated between both ends of the electronic component 11 when the measurement current Im that is an AC current flows to the electronic component 11 when the measurement AC voltage Vm is applied. A voltage detection signal Vv, which is an AC signal whose voltage value (amplitude) changes in proportion to the voltage value (amplitude) of the voltage V1 between both ends, is detected via the voltage application probes PL1 and PL2. Generate and output. In the following, in order to facilitate understanding of the invention, the amplitude (voltage value) of the voltage V1 between both ends is also denoted by V1. In this case, the voltage V1 between both ends includes the resistance components of the voltage application probes PL1 and PL2, and the contact resistances between the voltage application probes PL1 and PL2 and the terminals 11a and 11b of the electronic component 11 (see FIG. 1, the combined resistance of the resistance component and the contact resistance is schematically represented as resistors R1 and R2). Further, as will be described later, the capacitor as the electronic component 11 to be measured is generally represented by an equivalent circuit in which the resistance component 11d is connected in series to the original capacitor component 11c. This voltage drop is also included in the voltage V1 between both ends. In general, the resistance component 11d has a resistance value smaller than those of the resistors R1 and R2. Therefore, when the resistance value is sufficiently small to be negligible, a voltage drop in the resistance component 11d is obtained. Can not be considered. Further, since the voltage drop at the current detector 4 is extremely small, this voltage drop is ignored.

  The current detector 4 detects the measurement current Im flowing through the electronic component 11 via the voltage application probes PL1 and PL2 when the measurement AC voltage Vm is applied, and the current value (amplitude) of the measurement current Im. The current detection signal Vi, which is an AC signal whose voltage value (amplitude) changes in proportion to, is generated and output. In this example, the current detection unit 4 is arranged on the voltage application probe PL2 side as shown in FIG. 1, but may be arranged on the voltage application probe PL1 side. In the following description, in order to facilitate understanding of the invention, the amplitude (current value) of the measurement current Im is also denoted by the symbol Im.

  The processing unit 5 includes, for example, an A / D converter and a computer (both not shown), inputs the voltage detection signal Vv and the current detection signal Vi, and samples the voltage detection signal Vv. Is converted into voltage waveform data Dv indicating the instantaneous value by sampling, and by converting the current detection signal Vi into current waveform data Di indicating the instantaneous value by sampling, a voltage waveform corresponding to at least one cycle of the voltage detection signal Vv. A waveform data acquisition process for storing the data Dv and the current waveform data Di in the storage unit 6 is executed. Further, the processing unit 5 determines the phase difference θ between the voltage V1 between both ends and the measurement current Im (measurement AC voltage Vm and measurement) based on the voltage waveform data Dv and the current waveform data Di stored in the storage unit 6. The phase difference detection process for detecting the phase difference between the current Im and the current Im is executed, and the detected phase difference θ is stored in the storage unit 6. Further, the processing unit 5 outputs the voltage setting data Ds to the voltage generation unit 2 and executes a voltage setting process for setting the voltage value Vm of the measurement AC voltage Vm output from the voltage generation unit 2. The processing unit 5 measures and outputs the capacitance value C of the electronic component 11 (capacitor) based on the voltage waveform data Dv, the current waveform data Di, the phase difference θ, and the known frequency f of the measurement AC voltage Vm. The measurement process output to the unit 7 is executed.

  The storage unit 6 is composed of, for example, a rewritable storage device (such as a hard disk device or a RAM), and an operation program for the processing unit 5 and measurement to be applied to the electronic component 11 (capacitor) when measuring the capacitance value C. The specified voltage value Vr for the voltage value Vm of the AC voltage Vm for use is stored in advance. The storage unit 6 also stores the frequency f.

  The output unit 7 includes a display device such as a liquid crystal display device as an example, and displays the capacitance value C output from the processing unit 5 on the screen. In addition, it is possible to adopt a configuration in which the output unit 7 is configured by an interface device that transmits data to an external device, and the measured capacitance value C is output to the external device via the output unit 7. It is also possible to adopt a configuration in which the output unit 7 is configured by an interface device that stores data, and the measured capacitance value C is stored in the removable medium via the output unit 7.

  Next, together with the operation of the measuring apparatus 1, a measuring method will be described with reference to the drawings.

  In a state where the voltage generation unit 2 and the voltage detection unit 3 are connected to the electronic component 11 via the voltage application probes PL1 and PL2, the processing unit 5 first executes an initial voltage setting process. In this voltage setting process, the processing unit 5 reads the specified voltage value Vr from the storage unit 6 and outputs voltage setting data Ds indicating the specified voltage value Vr to the voltage generation unit 2, and is output from the voltage generation unit 2. The voltage value Vm of the measurement AC voltage Vm is set to the specified voltage value Vr. Thus, the voltage generator 2 sets the voltage value Vm to the specified voltage value Vr, generates the measurement AC voltage Vm, and applies it to both ends of the electronic component 11 (between both terminals 11a and 11b).

  Next, the processing unit 5 executes the first waveform data acquisition process in this state. In this waveform data acquisition process, the processing unit 5 receives and samples the voltage detection signal Vv and the current detection signal Vi to convert them into voltage waveform data Dv and current waveform data Di, and each of the waveform data Dv and Di One cycle of the voltage detection signal Vv is stored in the storage unit 6.

  Subsequently, the processing unit 5 executes a phase difference detection process (phase difference detection step). In this phase difference detection process, the processing unit 5 is based on the voltage waveform data Dv and the current waveform data Di stored in the storage unit 6, and the phase difference θ between the voltage V1 between both ends and the measurement current Im (for measurement) (Which is also a phase difference between the AC voltage Vm and the measurement current Im), and the detected phase difference θ is stored in the storage unit 6.

  Next, the processing unit 5 executes a second voltage setting process. In this voltage setting process, the processing unit 5 first reads the specified voltage value Vr and the phase difference θ from the storage unit 6 and calculates a corrected specified voltage value Vrc obtained by multiplying the specified voltage value Vr by 1 / sin θ. Next, the processing unit 5 outputs the voltage setting data Ds indicating the corrected specified voltage value Vrc to the voltage generating unit 2, and the voltage value Vm of the measurement AC voltage Vm output from the voltage generating unit 2 is this corrected specified value. Set to voltage value Vrc. As a result, the voltage generator 2 sets the voltage value Vm to the corrected specified voltage value Vrc, generates the measurement AC voltage Vm, and applies it to both ends of the electronic component 11 (between both terminals 11a and 11b). Step).

The reason why the AC voltage Vm for measurement is applied to the voltage generator 2 with the corrected specified voltage value Vrc as the voltage value Vm instead of the specified voltage value Vr will be described. As shown in FIG. 1, a capacitor as an electronic component 11 to be measured is generally represented by an equivalent circuit in which a resistance component 11d is connected in series to an original capacitor component 11c. In addition, the above-described resistors R1 and R2 are equivalently connected in series to the electronic component 11. That is, a series combined resistance of the resistors R1 and R2 and the resistor component 11d is connected in series to the capacitor component 11c. For this reason, even if the specified voltage value Vr is applied between both ends of the electronic component 11 (between both terminals 11a and 11b), the specified voltage value Vr is divided by the series combined resistor and the capacitor component 11c. The voltage Vc actually applied between both ends of the capacitor component 11c is Vr × sin θ (where θ is the phase difference between the voltage V1 between the both ends obtained by the above-described phase difference detection process and the measurement current Im). Thus, the voltage is lower than the specified voltage value Vr. Therefore, the voltage value Vm of the measurement AC voltage Vm output from the voltage generator 2 is defined as a corrected specified voltage value Vrc (= Vr × (1 / sin θ)) obtained by multiplying the specified voltage value Vr by 1 / sin θ in advance. The voltage Vc actually applied across the capacitor component 11c is set to the specified voltage value Vr as shown in the following equation.
Vc = Vrc × sin θ = Vr × (1 / sin θ)) × sin θ = Vr

  Subsequently, the processing unit 5 executes the second waveform data acquisition process after executing the second voltage setting process. In this waveform data acquisition process, the processing unit 5 receives and samples the voltage detection signal Vv and the current detection signal Vi to convert them into voltage waveform data Dv and current waveform data Di, and each of the waveform data Dv and Di One cycle of the voltage detection signal Vv is stored in the storage unit 6 (voltage detection step and current detection step).

  Next, the processing unit 5 performs a measurement process (measurement step). In this measurement process, the processing unit 5 first determines the alternating current for measurement based on the voltage waveform data Dv and the current waveform data Di (waveform data acquired in the second waveform data acquisition process) stored in the storage unit 6. The effective value Vrm of the voltage Vm and the effective value Irm of the measurement current Im are calculated. Next, the processing unit 5 calculates the impedance Z (= Vrm / Irm) of the electronic component 11 based on the calculated effective values Vrm and Irm. Subsequently, the processing unit 5 calculates the reactance X (= Z × sin θ) of the electronic component 11 based on the calculated impedance Z and the phase difference θ stored in the storage unit 6. Next, the processing unit 5 determines the capacitance value C (= 1 / (2π × f × X) of the electronic component 11 based on the calculated reactance X and the known frequency f (frequency f stored in the storage unit 6). )) Is calculated and stored in the storage unit 6. The capacitance value C calculated in this way is a value when the voltage Vc applied across the capacitor component 11c of the electronic component 11 is the specified voltage value Vr, and thus the capacitance value of the electronic component 11 is accurately determined. It is shown in Finally, the processing unit 5 outputs the calculated capacitance value C to the output unit 7 for display. Thereby, the measurement of the capacitance value C of the electronic component 11 is completed.

  As described above, in the measurement apparatus 1 and the measurement method, the phase difference detection process (phase difference detection step) for detecting the phase difference θ between the voltage V1 between both ends and the measurement current Im is executed, and the measurement process (measurement step) is performed. ) In the voltage setting process (application step) for the voltage generator 2, a pre-defined rule as the voltage value Vm of the AC voltage Vm for measurement when measuring the capacitance value C of the electronic component 11. The voltage generator 2 is caused to generate the measurement AC voltage Vm with the corrected specified voltage value Vrc obtained by multiplying the voltage value Vr by 1 / sin θ.

  Therefore, according to the measuring apparatus 1 and the measuring method, the voltage value of the voltage Vc actually applied across the capacitor component 11c of the capacitor as the electronic component 11 to be measured is accurately set to the specified voltage value Vr. The capacitance value C of the electronic component 11 can be measured in the state. Thereby, according to this measuring apparatus 1 and the measuring method, for example, a voltage-dependent measuring object such as a multilayer ceramic capacitor is applied with the specified voltage value Vr accurately applied between both ends of the capacitor component 11c. The accurate capacitance value C can be measured.

  In addition, although the capacitor has been described as an example of the electronic component 11 to be measured, the measurement apparatus 1 and the measurement method can be applied to the case where the inductor is the electronic component 11 to be measured. In this case, the phase difference detection step and the application step are executed in the same manner as when the capacitor as the electronic component 11 is set as the measurement target, thereby defining the inductor component of the inductor existing in series with the resistance component. An accurate inductance value of the inductor can be measured in a state where the voltage value Vr is applied.

  Moreover, although the measuring apparatus 1 gave and demonstrated the example which measures the impedance Z by a 2 terminal method, it can apply also when measuring the impedance Z by a 4 terminal method, In this case, it is applied to the capacitor component 11c. It is a measurement target even in a situation where the voltage drop at the resistance component 11d connected in series (the voltage drop at the resistance component connected in series to the inductor component when the measurement target is an inductor) cannot be ignored. The capacitance value (or inductance value) can be accurately measured in a state where the specified voltage value Vr is accurately applied to the capacitor component 11c (or inductor component) of the electronic component 11.

DESCRIPTION OF SYMBOLS 1 Measuring apparatus 2 Voltage generation part 3 Voltage detection part 4 Current detection part 5 Processing part 11 Electronic component (measurement object)
C Capacitance value f Frequency Im Measurement current V1 Voltage between both ends Vm Measurement AC voltage Vr Specified voltage value Vrc Correction specified voltage value

Claims (4)

A voltage generator that generates a measurement AC voltage to be applied to the measurement object, and a voltage that detects a voltage across the measurement object when a measurement current flows when the measurement AC voltage is applied. A measurement process for measuring a capacitance value of the capacitor as the measurement target based on the frequency of the detection unit, the current detection unit for detecting the measurement current, the voltage between both ends, the measurement current, and the AC voltage for measurement; A measuring device including a processing unit to be executed,
The processing unit performs a phase difference detection process for detecting a phase difference θ between the voltage between both ends and the measurement current, and when the measurement process is performed, A measuring apparatus for causing the voltage generating unit to generate the AC voltage for measurement with a corrected specified voltage value obtained by multiplying a specified voltage value specified in advance as a voltage value of the AC voltage for measurement by 1 / sin θ. A voltage generator that generates a measurement AC voltage to be applied to the measurement object, and a voltage that detects a voltage across the measurement object when a measurement current flows when the measurement AC voltage is applied. And a measurement process for measuring an inductance value of the inductor as the measurement object based on a frequency of the detection unit, a current detection unit for detecting the measurement current, the voltage between both ends, the measurement current, and the AC voltage for measurement. A measuring device including a processing unit to be executed,
The processing unit executes a phase difference detection process for detecting a phase difference θ between the voltage between both ends and the measurement current, and when the measurement process is executed, A measuring apparatus for causing the voltage generating unit to generate the AC voltage for measurement with a corrected specified voltage value obtained by multiplying a specified voltage value specified in advance as a voltage value of the AC voltage for measurement by 1 / sin θ. An application step of applying a measurement AC voltage to the measurement object; and a voltage detection step of detecting a voltage across the measurement object when a measurement current flows when the measurement AC voltage is applied. A measurement step of performing a current detection step of detecting the measurement current, and a measurement step of measuring a capacitance value of the capacitor as the measurement object based on the frequencies of the voltage between both ends, the measurement current, and the AC voltage for measurement. A method,
Performing a phase difference detection step of detecting a phase difference θ between the voltage between the both ends and the measurement current;
When executing the measurement step, a corrected specified voltage value obtained by multiplying a specified voltage value, which is specified in advance as the voltage value of the AC voltage for measurement at the time of measuring the capacitance value in the applying step, by 1 / sin θ. A measurement method in which the alternating voltage for measurement is applied. An application step of applying a measurement AC voltage to the measurement object; and a voltage detection step of detecting a voltage across the measurement object when a measurement current flows when the measurement AC voltage is applied. A measurement step of performing a current detection step of detecting the measurement current, and a measurement step of measuring an inductance value of the inductor as the measurement object based on the frequencies of the voltage between both ends, the measurement current, and the AC voltage for measurement. A method,
Performing a phase difference detection step of detecting a phase difference θ between the voltage between the both ends and the measurement current;
When executing the measurement step, a corrected specified voltage value obtained by multiplying a specified voltage value, which is specified in advance as the voltage value of the AC voltage for measurement at the time of measuring the inductance value, by 1 / sin θ in the applying step. A measurement method in which the alternating voltage for measurement is applied.

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