Short-circuit detection device and short-circuit detection method

Abstract

A short-circuit detection device that detects a short circuit occurring in an object to be detected measures a capacitance value of the object to be detected, and determines a current value of a current supplied to the object to be detected on the basis of the measured capacitance value. Furthermore, the short-circuit detection device supplies a current of the determined current value to the object to be detected, and detects a short circuit of the object to be detected in a state where the current is supplied to the object to be detected.

Description

Technical Field

[0001] This invention relates to a short-circuit detection device and a short-circuit detection method. Background Technology

[0002] JP2020-71054A discloses a micro short-circuit sensing device that detects micro short circuits by measuring the voltage across the target object while a constant current is supplied to a lithium secondary battery. Summary of the Invention

[0003] The inspection device described above is an inspection device that supplies current to the object being inspected, such as a lithium secondary battery. However, the current value supplied to the object being inspected can only be set according to the rated current value of the object being inspected and matched to each object being inspected.

[0004] This invention was made in view of such a problem point, and its purpose is to provide a short circuit detection device and a short circuit detection method that can detect short circuits occurring in a test object without setting the current value supplied to the test object for each test object.

[0005] According to a certain aspect of the present invention, a short-circuit detection device for detecting a short circuit occurring in a test object includes: a capacitance measuring unit for measuring the capacitance value of the test object; and a current determining unit for determining a current value to be supplied to the test object based on the capacitance value measured by the capacitance measuring unit. Furthermore, the short-circuit detection device includes: a current supply unit for supplying a current of the current value determined by the current determining unit to the test object; and a detection unit for detecting a short circuit in the test object while the current supply unit has supplied the current to the test object.

[0006] According to this scheme, by measuring the capacitance value of the object to be tested before supplying current to it, the current value supplied to the object to be tested can be determined based on the capacitance value. Therefore, short circuit detection can be performed without setting the current value supplied to each object to be tested. Attached Figure Description

[0007] Figure 1 This is a block diagram illustrating the functional configuration of the short-circuit detection device in the first embodiment of the present invention.

[0008] Figure 2 This is a flowchart illustrating the processing procedure of the short-circuit detection method in the first embodiment.

[0009] Figure 3 This is a block diagram illustrating a variation of the short-circuit detection device in the first embodiment. Detailed Implementation

[0010] Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings.

[0011] (First Implementation)

[0012] Figure 1 This is a block diagram illustrating the functional configuration of the short-circuit detection device 100 in the first embodiment.

[0013] The short-circuit detection device 100 is a device used to detect short circuits occurring in the object under test 1. The short circuits referred to here include not only stable short circuits, but also short-term short circuits such as short-term insulation failures and insulation degradation caused by abnormalities occurring in the object under test 1.

[0014] The main causes of short-term short circuits include, for example, the introduction of metallic foreign objects into the electrodes constituting the battery, the generation of contamination, flash between the battery electrodes and the battery casing, cracks generated in multilayer ceramic capacitors, and micro-short circuits between substrate patterns.

[0015] Thus, the short-circuit detection device 100 detects short circuits caused by the aforementioned abnormalities occurring in the object under test 1. The short-circuit detection device 100 is used, for example, for measuring or testing the object under test 1 by supplying (applying) a DC signal to it.

[0016] In the first embodiment, the short-circuit detection device 100 supplies a DC voltage to the object to be detected 1, thereby determining the insulation resistance value R of the object to be detected 1 based on the magnitude of the leakage current output from the negative terminal (-) of the object to be detected 1.

[0017] The object to be detected is an object with a capacitance of at least C. When a DC signal is supplied to the object, the voltage signal generated in the object or the current signal flowing through the object will temporarily change due to an anomaly occurring in the object.

[0018] Hereinafter, a rise in the above electrical signal from the standard level followed by a fall will be referred to as a "temporary rise," and a fall in the electrical signal from the standard level followed by a rise will be referred to as a "temporary fall." In addition, these temporary changes will also be simply referred to as "changes."

[0019] As an example of the object of testing, a secondary battery can be listed. A secondary battery is a storage device that is configured to be charged and discharged, and includes capacitor-type storage elements such as double-layer capacitors. A secondary battery can be an assembled battery composed of multiple unit batteries connected in parallel, series, or series-parallel, or it can be a single cell.

[0020] Examples of secondary batteries include lead-acid batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lithium metal batteries, lithium-ion batteries, lithium-ion polymer batteries, lithium-ion all-solid-state batteries, and sodium-ion batteries. In addition, aqueous double-layer capacitors or drainable aqueous double-layer capacitors can also be used as secondary batteries.

[0021] In the first embodiment, the test object 1 is a lithium-ion battery before liquid injection. The lithium-ion battery has an insulation resistance value R and a capacitance value C, and is represented by an equivalent circuit in which they are connected in parallel.

[0022] In the first embodiment, the positive (+) terminal of the object to be detected 1 is connected to the connection terminal 101 of the short circuit detection device 100, and the negative (-) terminal of the object to be detected 1 is connected to the connection terminal 102 of the short circuit detection device 100.

[0023] The short-circuit detection device 100 includes a current limiter 10, a constant current source 11, a constant voltage source 12, a switch unit 13, a capacitance measurement power supply 20, a switch unit 21, a capacitance measurement current measuring unit 22, a voltage measuring unit 120, a current measuring unit 130, a fluctuation detection circuit 140, and an AD converter (analog-to-digital converter) 150. Furthermore, the short-circuit detection device 100 includes a processing unit 200, a display unit 210, an operation receiving unit 220, and a fluctuation detection circuit 240.

[0024] The current limiter 10 is connected to the output terminal of the constant voltage source 12. The current limiter 10 limits the current supplied from the constant voltage source 12 to the object being detected 1 according to the instructions of the processing unit 200.

[0025] The constant current source 11 constitutes a constant current supply unit that supplies a current I controlled to maintain a predetermined current value to the object under test 1. Hereinafter, the predetermined current value is set as I1. The constant current source 11 supplies a constant DC current to the positive (+) terminal of the object under test 1 via the connection terminal 101 of the short-circuit detection device 100, thereby charging the object under test 1.

[0026] The constant voltage source 12 constitutes a constant voltage supply unit that supplies a voltage V controlled to maintain a predetermined voltage value to the object under test 1. Hereinafter, the predetermined voltage value is set as V1. In order to detect the leakage current of the object under test 1, the constant voltage source 12 supplies a constant DC voltage between the positive and negative terminals of the object under test 1 via the connection terminal 101.

[0027] The switching unit 13 switches between the capacitance measurement power supply 20, the constant current source 11, and the constant voltage source 12 to select the power supply that can be connected to the object under test 1. The switching unit 13 connects the positive terminal (+) of the object under test 1 to the capacitance measurement power supply 20 according to the instructions of the processing unit 200. After the capacitance value of the object under test 1 is measured, the switching unit 13 switches the power supply connected to the object under test 1 from the capacitance measurement power supply 20 to either the constant current source 11 or the constant voltage source 12.

[0028] The capacitance measurement power supply 20 constitutes a voltage supply unit that supplies the capacitance measurement voltage to the object under test 1. The capacitance measurement power supply 20 supplies an AC voltage to the positive (+) terminal of the object under test 1 via the connection terminal 101 of the short-circuit detection device 100 as the capacitance measurement voltage, thereby charging and discharging the object under test 1. The capacitance measurement voltage is an AC voltage with multiple frequency components.

[0029] The switching unit 21 switches the connection between the current measuring unit 130 and the capacitance measuring current measuring unit 22 connected to the current measuring unit of the object to be tested 1. The switching unit 21 connects the negative terminal (-) of the object to be tested 1 to the capacitance measuring current measuring unit 22 according to the instructions of the processing unit 200. After the capacitance value C of the object to be tested 1 is measured, the switching unit 21 switches the connection between the capacitance measuring current measuring unit 22 and the current measuring unit 130 connected to the object to be tested 1.

[0030] The capacitance measurement current measurement unit 22 performs current measurement processing to measure the capacitance value C of the object to be tested 1 according to the capacitance measurement command from the processing unit 200.

[0031] The capacitance measuring current measuring unit 22 measures the alternating current of the test object 1 based on the response signal generated in the test object 1 when an alternating signal is supplied between the positive (+) and negative (-) terminals of the test object 1. The capacitance measuring current measuring unit 22 outputs a voltage signal representing the magnitude of the measured alternating current as a current detection signal Vci to the AD converter 150.

[0032] The current measuring unit 130 constitutes a measuring unit for measuring the magnitude of the current generated in the object being tested 1. The current measuring unit 130 acquires a current detection signal Vi that represents the current value of the object being tested 1.

[0033] In the first embodiment, the current measuring unit 130 measures the magnitude of the leakage current output from the negative terminal (-) of the object being detected 1. Furthermore, the current measuring unit 130 outputs a voltage signal representing the magnitude of the measured current as a current detection signal Vi to the AD converter 150.

[0034] For example, when the object to be detected 1 is charged by the constant current source 11, the leakage current is in the milliampere (mA) range. On the other hand, when the voltage of the object to be detected 1 is maintained at a voltage value V1 by the constant voltage source 12, the leakage current is in the nanoampere (nA) or microampere (μA) range.

[0035] The current measuring unit 130 is configured, for example, as an IV conversion circuit that converts the input current into a voltage. In addition, the current measuring unit 130 generates a measuring signal Vmi that represents the magnitude of the current output from the negative (-) terminal of the object being detected 1, and outputs the generated measuring signal Vmi to the variation detection circuit 140.

[0036] The variation detection circuit 140 detects variations in the measurement signal Vmi caused by a short circuit occurring in the object to be detected 1. In the first embodiment, the variation detection circuit 140 detects temporary variations in the measurement signal Vmi caused by a short circuit associated with the introduction of foreign matter into the object to be detected 1.

[0037] For example, the change detection circuit 140 is composed of a comparator circuit. The change detection circuit 140 outputs a change detection signal Vdi, representing the detected change, to the A / D converter 150.

[0038] The variation detection circuit 240 detects variations in the measurement signal Vmv caused by a short circuit occurring in the object to be detected 1. In the first embodiment, the variation detection circuit 240 detects temporary variations in the measurement signal Vmv caused by a short circuit associated with the introduction of foreign matter into the object to be detected 1.

[0039] The change detection circuit 240 has the same or equivalent configuration as the change detection circuit 140. The change detection circuit 240 is, for example, constructed from a comparator circuit. The change detection circuit 240 outputs a change detection signal Vdv, representing the detected change, to the AD converter 150.

[0040] The AD converter 150 samples the current detection signal Vci from the current measuring unit 22 for capacitance measurement at a predetermined period, and outputs the data generated by the sampling to the processing unit 200.

[0041] Similarly, the AD converter 150 samples the current detection signal Vi from the current measuring unit 130, the change detection signal Vdi from the change detection circuit 140, the voltage detection signal Vv from the voltage measuring unit 120, and the change detection signal Vdv from the change detection circuit 240 at a predetermined period. Furthermore, the AD converter 150 outputs the data generated through sampling to the processing unit 200.

[0042] The processing unit 200 is a computer consisting of a processor, ROM (Read Only Memory), RAM (Random Access Memory), mass storage devices, input / output interfaces, and buses connecting them. Examples of processors include CPUs (Central Processing Units) and MPUs (Micro Processor Units). Examples of mass storage devices include HDDs (Hard Disk Drives) and SSDs (Solid State Drives).

[0043] The processing unit 200 controls the current limiter 10, constant current source 11, constant voltage source 12, switch unit 13, capacitance measurement power supply 20, and switch unit 21 that constitute the power supply unit 110.

[0044] The processing unit 200 performs short-circuit detection processing to detect short circuits occurring in the object under test 1. For example, when the operation receiving unit 220 receives a request signal requesting the execution of short-circuit detection processing, the processing unit 200 performs short-circuit detection processing.

[0045] In the above short-circuit detection process, firstly, the processing unit 200 controls the connection of the switch unit 13 by connecting the capacitance measurement power supply 20 to the positive (+) terminal of the object to be tested 1. Then, the processing unit 200 controls the capacitance measurement power supply 20 to supply an AC voltage having multiple frequency components to the object to be tested 1.

[0046] The processing unit 200 controls the switch unit 21 to connect the capacitance measuring current measuring unit 22 to the negative terminal (-) of the object to be tested 1. Then, the processing unit 200 controls the capacitance measuring current measuring unit 22 to measure the current value of the current flowing through the object to be tested 1 through the AC voltage supplied by the capacitance measuring power supply 20.

[0047] The processing unit 200 acquires a current detection signal Vci, representing the current value of the object to be detected 1, from the current measuring unit 22 for capacitance measurement via the AD converter 150. Then, the processing unit 200 measures the capacitance value C of the object to be detected 1 based on the current detection signal Vci. Thus, the processing unit 200 measures the capacitance value C using the AC impedance measurement method.

[0048] After measuring the capacitance value C, the processing unit 200 uses the measured capacitance value C of the object to be detected 1 to determine the current value I1 of the current I output from the constant current source 11. That is, the processing unit 200 is configured as a current determination unit that determines the current value I1 of the current I supplied to the object to be detected 1 based on the measured capacitance value C.

[0049] In the object being tested 1, when a current I of value I1 is supplied to a capacitor with capacitance value C, the voltage Vf between the two ends of the capacitor when the capacitor is fully charged is represented by the current value I1, capacitance value C and charging time Tc required to fully charge, as shown in equation (1).

[0050] Vf=I1*Tc / C…(1)

[0051] For example, when the current value I1 supplied to the object being tested is fixed regardless of the object being tested, the charging time Tc will vary depending on the capacitance value C of each object being tested. Furthermore, it is assumed that the current value I1 must be reduced according to the capacitance value C to avoid damaging the object being tested. Therefore, the current value I1 needs to be set to match the electrical characteristics of each object being tested.

[0052] As a measure, the processing unit 200 in the first embodiment determines the current value I1 of the current I based on the measured capacitance value C of the object to be detected 1.

[0053] Next, the processing unit 200 controls the operation of the constant current source 11 and the constant voltage source 12 based on the voltage detection signal Vv and the current detection signal Vi.

[0054] Specifically, after determining the current value I1 of the current I supplied to the object to be detected 1, the processing unit 200 acquires a voltage detection signal Vv representing the voltage value of the object to be detected 1 via the AD converter 150.

[0055] Next, the processing unit 200 controls the connection of the switching unit 13 by connecting the constant current source 11 to the positive (+) terminal of the object to be detected 1. Then, the processing unit 200 controls the constant current source 11 to maintain the current I that charges the object to be detected by the constant current source 11 at a constant current value I1 based on the current detection signal Vi.

[0056] At this time, the processing unit 200 determines, based on the voltage detection signal Vv, whether the voltage generated between the positive (+) and negative (-) terminals of the object being detected 1 has reached the specified voltage value V1.

[0057] When the voltage of the object being tested 1 reaches a voltage value V1, the processing unit 200 controls the connection of the switching unit 13 to switch the power supply connected to the object being tested 1 from a constant current source 11 to a constant voltage source 12. Then, the processing unit 200 controls the constant voltage source 12 based on the voltage detection signal Vv to maintain the voltage generated between the two poles of the object being tested 1 at a constant voltage value V1. That is, the processing unit 200 in the first embodiment uses the constant voltage source 12 for constant voltage control.

[0058] Thus, when the above request signal is received, the processing unit 200 controls the operation of the power supply unit 110 to charge the object to be detected 1 by maintaining a current I at a current value I1, and then continuously supplying a voltage value V1 to the object to be detected 1.

[0059] When power is supplied to the object being detected 1 from the power supply unit 110, the processing unit 200 acquires a change detection signal Vdi or a change detection signal Vdv via the AD converter 150. Then, the processing unit 200 determines whether a short circuit has occurred due to an abnormality that may occur in the object being detected 1 based on the change detection signal Vdi or the change detection signal Vdv.

[0060] Furthermore, the processing unit 200 performs calculations on the physical quantities of the object to be detected 1 based on the current detection signal Vi and the voltage detection signal Vv acquired via the AD converter 150. For example, the leakage current value and the insulation resistance value R of the object to be detected 1 can be listed as physical quantities of the object to be detected 1. The processing unit 200 outputs the determination result or calculation result indicating whether a short circuit exists to the display unit 210.

[0061] The display unit 210 generates and displays image data representing the determination result or calculation result output from the processing unit 200. For example, the display unit 210 may be composed of an LED (Light Emitting Diode) display, a liquid crystal panel, or a touch panel.

[0062] The operation receiving unit 220 accepts user input operations and outputs an operation signal indicating the accepted input operation to the processing unit 200. The operation receiving unit 220 may be composed of, for example, buttons located near the screen of the display unit 210, touch sensors built into the touch panel, or keyboards and mice.

[0063] The operation receiving unit 220 outputs the short-circuit detection request to the processing unit 200, for example, by accepting a user operation that presses the execute button for short-circuit detection processing. As a result, short-circuit detection processing is performed in the short-circuit detection device 100.

[0064] Next, the operation of the short-circuit detection device 100 in the first embodiment will be explained.

[0065] First, in the short-circuit detection device 100, for example, when a user performs an input operation using the operation receiving unit 220, the operation receiving unit 220 outputs an operation signal to the processing unit 200. Then, when the operation signal is identified as a request signal for short-circuit detection processing, the processing unit 200 begins short-circuit detection processing.

[0066] First, the processing unit 200 measures the capacitance value C of the object to be tested, 1.

[0067] Specifically, the processing unit 200 switches the capacitance measurement power supply 20 to the positive (+) terminal of the object to be tested 1 via the switching unit 13, and switches the capacitance measurement current measurement unit 22 to the negative (-) terminal of the object to be tested 1 via the switching unit 21. Then, the processing unit 200 controls the capacitance measurement power supply 20 to supply a capacitance measurement voltage to the object to be tested 1.

[0068] In this state, the capacitance measurement current measuring unit 22 measures the alternating current flowing through the object being tested 1 and outputs a current detection signal Vci, representing the magnitude of the alternating current flowing through the object being tested 1, to the AD converter 150. The AD converter 150 outputs data representing the magnitude of the current detection signal Vci to the processing unit 200. The processing unit 200 calculates the capacitance value C of the object being tested 1 based on the current detection signal Vci.

[0069] Next, the processing unit 200 determines the current value I1 of the current I supplied to the object to be detected 1 based on the calculated capacitance value C. Specifically, the processing unit 200 uses the capacitance value C of the object to be detected 1 to calculate the current value I1 of the current I to be supplied. For example, if the appropriately determined coefficient is k, the value obtained by calculating k·C is set as the current value I1. As another example, if the voltage Va at full charge and the charging time Tc are given, the value obtained by calculating Va·C / Tc is set as the current value I1. Then, the processing unit 200 supplies the current I representing the determined current value I1 to the object to be detected 1.

[0070] Subsequently, the processing unit 200 switches the constant current source 11 to the positive (+) terminal of the object to be detected 1 via the switching unit 13, and the switching unit 21 connects the current measuring unit 130 to the negative (-) terminal of the object to be detected 1 via the switching unit 21. The processing unit 200 controls the constant current source 11 to make the current I with current value I1 flow through the object to be detected 1.

[0071] When the constant current source 11 supplies a current I with a current value I1, the processing unit 200 detects a short circuit that occurs in the object to be detected 1.

[0072] Specifically, the current measuring unit 130 outputs a measuring signal Vmi, indicating the magnitude of the current flowing through the object being tested 1, to the variation detection circuit 140. Based on the measuring signal Vmi, the variation detection circuit 140 outputs a variation detection signal Vdi, indicating whether the object being tested 1 is short-circuited, to the AD converter 150. The AD converter 150 outputs data obtained by sampling the variation detection signal Vdi to the processing unit 200. The processing unit 200 detects a short circuit occurring in the object being tested 1 based on the data representing the variation detection signal Vdi.

[0073] It should be noted that in the first embodiment, the processing unit 200 uses the change detection signal Vdi of the change detection circuit 140 to detect the short circuit of the object to be detected 1, but the change detection signal Vdv of the change detection circuit 240 can also be used to detect the short circuit of the object to be detected 1.

[0074] Next, refer to Figure 2 The short-circuit detection method in the first embodiment will be described.

[0075] Figure 2 This is a flowchart illustrating an example of a short-circuit detection method performed by the short-circuit detection device 100.

[0076] First, in the short-circuit detection device 100, for example, when a user performs an input operation using the operation receiving unit 220, the operation receiving unit 220 outputs an operation signal to the processing unit 200. Then, when the operation signal is identified as a request for short-circuit detection, the processing unit 200 begins short-circuit detection.

[0077] In step S1, the processing unit 200 measures the capacitance value C of the object to be detected 1.

[0078] In step S2, the processing unit 200 determines the current value I1 of the current I supplied to the detection object 1 based on the capacitance value C of the detection object 1. The processing unit 200 uses the capacitance value C obtained in step S1 to calculate the current value I1 of the current I.

[0079] In step S3, the processing unit 200 supplies the current I of the determined current value I1 to the object to be detected 1.

[0080] Specifically, the processing unit 200 switches the constant current source 11 to the positive (+) terminal of the object to be detected 1 via the switching unit 13, and switches the capacitance measurement current measuring unit 22 to the negative (-) terminal of the object to be detected 1 via the switching unit 21. The processing unit 200 controls the constant current source 11 to make the current I of the current value I1 obtained in step S2 flow through the object to be detected 1.

[0081] In step S4, the processing unit 200 detects a short circuit in the object to be detected 1 while supplying a current I that is maintained at a constant current value I1 to the object to be detected 1.

[0082] Next, the effects achieved by the first embodiment will be explained.

[0083] The short-circuit detection device 100 in the first embodiment includes: a capacitance measuring power supply 20 and a capacitance measuring current measuring unit 22 (capacitance measuring unit) for measuring the capacitance value C of the object to be tested 1; and a processing unit 200 (current determining unit) for determining the current value I1 of the current I supplied to the object to be tested 1. Furthermore, the short-circuit detection device 100 includes: a constant current source 11 (current supply unit) for supplying current I to the object to be tested 1; and a current measuring unit 130 and a variable detection circuit 140 (detection unit) for detecting short circuits in the object to be tested 1.

[0084] Furthermore, the capacitance measuring power supply 20 and the capacitance measuring current measuring unit 22 measure the capacitance value C of the object to be tested 1. The processing unit 200 (current determination unit) determines the current value I1 of the current I supplied to the object to be tested 1 based on the capacitance value C measured by the capacitance measuring power supply 20 and the capacitance measuring current measuring unit 22 (capacitance measuring unit).

[0085] Furthermore, the constant current source 11 supplies the current I, which is the current value I1 determined by the processing unit 200 (current determination unit), to the object to be detected 1. The current measuring unit 130 and the variation detection circuit 140 (detection unit) detect the short circuit of the object to be detected 1 when the constant current source 11 supplies the current I, which is the current value I1, to the object to be detected 1.

[0086] According to this configuration, the short-circuit detection device 100 can determine the current value I1 of the current I based on the capacitance value C of the object being detected 1 before supplying current I to it. Therefore, it is not necessary to set the current value I1 of the current I supplied to each object being detected 1 individually to detect a short circuit occurring in the object being detected 1.

[0087] Hereinafter, several variations of the short-circuit detection device 100 in the first embodiment will be described. Since these are partial changes to the first embodiment, the descriptions of the parts that are the same as those in the first embodiment will be omitted.

[0088] (First variation)

[0089] Figure 3 This is a block diagram illustrating a modified example of the configuration of the short-circuit detection device 100 in the first embodiment.

[0090] In the first variation, the short-circuit detection device 100, in addition to having... Figure 1 In addition to the configuration of the short-circuit detection device 100 shown, it also includes a storage unit 230.

[0091] The storage unit 230 is configured as a storage unit that stores the detection time T in advance before the processing unit 200 determines the current value I1. The detection time T is the time used by the processing unit 200 to detect the short circuit of the object to be detected 1.

[0092] As a specific example, when a user performs an input operation using the operation receiving unit 220, the operation receiving unit 220 outputs an operation signal corresponding to the input operation to the processing unit 200. Then, the processing unit 200 determines whether the operation signal is a setting signal representing a detection time T. If the operation signal is identified as a setting signal, the detection time T represented by the setting signal is stored in the storage unit 230. For example, the detection time T is set to 5 milliseconds.

[0093] Subsequently, when the capacitance value C of the object to be tested 1 is measured by the capacitance measuring power supply 20 and the capacitance measuring current measuring unit 22, the processing unit 200 determines the current value I1 of the current I based on the capacitance value C and the detection time T stored in the storage unit 230.

[0094] Next, the effects achieved by the first variation will be explained.

[0095] In the first variation, the short-circuit detection device 100, in addition to having... Figure 1 In addition to the configuration of the short-circuit detection device 100 shown, it also includes a storage unit 230 (storage unit). In the storage unit 230, the detection time T is stored before the processing unit 200 (current determination unit) determines the current value I1 of the current I supplied to the detection target 1.

[0096] Furthermore, the processing unit 200 (current determination unit) determines the current value I1 of the current I based on the detection time T stored in the storage unit 230 and the capacitance value C measured by the capacitance measurement power supply 20 and the capacitance measurement current measurement unit 22 (capacitance measurement unit).

[0097] According to this configuration, the short-circuit detection device 100 supplies a current I to the object being detected, which takes into account not only the capacitance value C of the object being detected 1 but also a pre-set detection time T. By determining the current value I1 considering not only the capacitance value C but also the detection time T, an appropriate current I suitable for short-circuit detection of the object being detected 1 can be supplied to the object being detected within the pre-set detection time T. Therefore, short circuits in the object being detected 1 can be detected with high accuracy within the predetermined time.

[0098] (Second variation)

[0099] like Figure 3 As shown, the short-circuit detection device 100 in the second modification is similar to that in the first modification, except that it has Figure 1 In addition to the configuration of the short-circuit detection device 100 shown, it also includes a storage unit 230.

[0100] The storage unit 230 is configured to store a preset current value Is in advance before the processing unit 200 determines the current value I1 of the current I. The preset current value Is is the current value of the current I determined based on the electrical characteristics of the object being detected 1. In the second variation, the preset current value Is is set to a current value suitable for detecting a short circuit current I that occurs in the object being detected 1.

[0101] As a specific example, when a user performs an input operation using the operation receiving unit 220, the operation receiving unit 220 outputs an operation signal corresponding to the input operation to the processing unit 200. Then, if the operation signal is identified as a setting signal representing a set current value Is, the processing unit 200 stores the set current value Is represented by the setting signal in the storage unit 230.

[0102] Subsequently, when the capacitance value C of the object to be tested 1 is measured by the capacitance measuring power supply 20 and the capacitance measuring current measuring unit 22, the processing unit 200 determines the current value I1 of the current I supplied to the object to be tested 1 based on the capacitance value C.

[0103] Then, the processing unit 200 determines whether the set current value Is stored in the storage unit 230 is lower than or equal to the determined current value I1. If the set current value Is is lower than or equal to the current value I1, the processing unit 200 detects a short circuit in the object 1 while the current I of the set current value Is is supplied to the object 1.

[0104] On the other hand, when the set current value Is is greater than the current value I1, the processing unit 200 detects a short circuit in the object 1 under the condition that the current I of the determined current value I1 is supplied to the object 1. Therefore, a short circuit in the object 1 can be detected in a manner that matches the capacitance value C.

[0105] Next, the effects achieved by the second variation will be explained.

[0106] The short-circuit detection device 100 in the second modification is similar to that in the first modification, except that it has Figure 1 In addition to the configuration of the short-circuit detection device 100 shown, it also includes a storage unit 230 (storage unit). In the storage unit 230, a preset setting current value Is is stored before the processing unit 200 (current determination unit) determines the current value I1 of the current I supplied to the detection target 1.

[0107] Furthermore, the processing unit 200 (current determination unit) determines the current value I1 of the current I supplied to the object under test 1 based on the capacitance value C measured by the capacitance measuring power supply 20 and the capacitance measuring current measuring unit 22. If the set current value Is stored in the storage unit 230 is lower than or equal to the determined current value I1, the processing unit 200 detects a short circuit in the object under test 1 while the current I of the set current value Is is supplied to the object under test 1.

[0108] According to this configuration, when the current value I1 determined based on the capacitance value C is greater than the set current value Is, the current I of the set current value Is is supplied to the object to be detected 1.

[0109] Thus, by supplying a weak current I, which is less than or equal to the capacitance value C, to the object being detected 1, a short circuit in the object being detected can be detected by means of a weak current I that is well-matched to the electrical characteristics of the object being detected and is easy to detect. Furthermore, supplying excessive current to the object being detected can be avoided, and the power consumption required for short circuit detection processing can be suppressed.

[0110] (Third variation)

[0111] The short-circuit detection device 100 in the third variation and Figure 3 The configuration shown is the same, but specific functions have been added to the processing unit 200.

[0112] Specifically, the larger the capacitance value C of the detected object 1, the larger the current value I1 of the current I supplied to the detected object 1 by the processing unit 200; the smaller the capacitance value C of the detected object 1, the smaller the current value I1 of the current I supplied to the detected object 1 by the processing unit 200.

[0113] In this process, the comparison object for the capacitance value C can be either the capacitance value preset in the storage unit 230 of the short circuit detection device 100, or the capacitance value C at the time of the last short circuit detection.

[0114] Furthermore, the method of increasing or decreasing the current value I1 can be either to increase or decrease the value of the preset current value Is in the storage unit 230 of the short circuit detection device 100, or to use the current value I1 calculated based on the detection time T or the capacitance value C.

[0115] Next, the effects achieved by the third variation will be explained.

[0116] The larger the capacitance value C, the larger the current value I1 of the current I supplied to the detection object 1 by the processing unit 200 (current determining unit) in the third modified example; the smaller the capacitance value C, the smaller the current value I1 of the current I supplied to the detection object 1 by the processing unit 200.

[0117] According to this configuration, if the capacitance C of the capacitor constituting the object to be detected 1 is relatively large, it will take time to charge the object to be detected 1, thereby the short-circuit detection device 100 supplies a larger current I with a value I1. On the other hand, if the capacitance C of the object to be detected 1 is small, the short-circuit detection device 100 supplies a smaller current I with a value I1.

[0118] Therefore, even if the capacitance value C of each object 1 being detected is different, the current value I1 will be adjusted according to the capacitance value C, so that the detection time of the object 1 when it is short-circuited can be made similar to each other.

[0119] (Fourth variation)

[0120] The short-circuit detection device 100 in the fourth variation and Figure 3 The configuration shown is the same, but specific functions have been added to the processing unit 200.

[0121] Specifically, the processing unit 200 controls the constant current source 11 in such a way that the value obtained by dividing the capacitance value C of the object to be detected 1 by the current value I1 of the current I supplied to the object to be detected 1 is constant.

[0122] For example, the processing unit 200 controls the operation of the constant current source 11 to supply a current I of 5 [mA] to the object to be detected when the capacitance value C1 is 10 [μF], and to supply a current I of 2.5 [mA] to the object to be detected when the capacitance value C2 is 5 [μF].

[0123] Next, the effects achieved by the fourth variation will be explained.

[0124] In the fourth variation, the processing unit 200 (current determination unit) controls the constant current source 11 (current supply unit) in such a way that the value obtained by dividing the capacitance value C by the current value I1 supplied to the detection object 1 is constant.

[0125] In the object being tested 1, when a current of value I1 is supplied to a capacitor with capacitance value C, the voltage V between the two ends of the capacitor after time t seconds is as shown in equation (2). When equation (2) is solved for time t, it is as shown in equation (3).

[0126] V=I1*t / C…(2)

[0127] t=V*C / I1…(3)

[0128] Therefore, the short circuit detection device 100 is adjusted to keep the value obtained by dividing the capacitance value C of the object to be detected by the current value I1 of the current supplied to the object to be detected constant, so that even if the capacitance values ​​C of the objects to be detected are different, a short circuit can be detected in the same detection time.

[0129] (Fifth variation)

[0130] like Figure 3 As shown, the short-circuit detection device 100 in the fifth modification is similar to the above-described modifications, except that it has Figure 1 In addition to the configuration of the short-circuit detection device 100 shown, it also includes a storage unit 230.

[0131] The storage unit 230 is configured to store a preset upper limit current value Iu before the processing unit 200 determines the current value I1 of the current I supplied to the detection object 1.

[0132] The upper limit current value Iu represents the upper limit of the current I that can be supplied to the object being detected 1. The upper limit current value Iu is predetermined based on the electrical characteristics of the object being detected 1 to avoid supplying excessive current to the object being detected 1. The upper limit current value Iu is, for example, set to a number [A].

[0133] Then, the capacitance value C of the object to be tested is measured by the capacitance measuring power supply 20 and the capacitance measuring current measuring unit 22, and the processing unit 200 determines the current value I1 of the current I supplied to the object to be tested based on the measured capacitance value C.

[0134] Then, the processing unit 200 determines whether the upper limit current value Iu stored in the storage unit 230 is greater than or equal to the determined current value I1. If the upper limit current value Iu is greater than or equal to the current value I1, the processing unit 200 detects a short circuit in the object to be detected while the current I at the determined current value I1 is supplied to the object to be detected.

[0135] On the other hand, when the upper limit current value Iu is less than the current value I1, the processing unit 200 detects the short circuit of the detection object 1 while the current I of the upper limit current value Iu is supplied to the detection object 1.

[0136] Next, the effects achieved by the fifth variation will be explained.

[0137] The short-circuit detection device 100 in the fifth variation, in addition to having Figure 1In addition to the configuration of the short-circuit detection device 100 shown, it also includes a storage unit 230 (storage unit). In the storage unit 230, before the processing unit 200 (current determination unit) determines the current value I1 of the current I supplied to the object to be detected 1, an upper limit current value Iu representing the upper limit of the current I is stored in advance based on the electrical characteristics of the object to be detected 1.

[0138] The processing unit 200 (current determination unit) determines the current value I1 of the current I supplied to the object under test 1 based on the capacitance value C measured by the capacitance measuring power supply 20 and the capacitance measuring current measuring unit 22 (capacitance measuring unit). Then, if the upper limit current value Iu is greater than or equal to the determined current value I1, the processing unit 200 (current determination unit) detects a short circuit in the object under test 1 while the current I of the determined current value I1 is supplied to the object under test 1.

[0139] According to this configuration, the short-circuit detection device 100 presets an upper limit current value Iu. When this upper limit current value Iu is greater than or equal to a current value I1 determined based on the capacitance value C, the device supplies current I of the determined current value I1 to the object being detected 1. On the other hand, when the upper limit current value Iu is less than the current value I1 determined based on the capacitance value C, the short-circuit detection device 100 limits the current I supplied to the object being detected to the upper limit current value Iu, so as to prevent the current value I1 from exceeding the upper limit current value Iu.

[0140] Therefore, the current value of current I can be adjusted to prevent excessive current from flowing through the object being detected 1, thus avoiding the situation where the object being detected 1 is burned or damaged, and short circuits in the object being detected 1 can be detected.

[0141] The embodiments of the present invention have been described above. However, the above embodiments only illustrate a part of the application examples of the present invention and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

[0142] In the above embodiment, the detection time T, the set current value Is, or the upper limit current value Iu are set to the processing unit 200 by the operation receiving unit 220 provided in the short circuit detection device 100, but this embodiment is not limited to this. For example, if the detection time T, the set current value Is, or the upper limit current value Iu can be set to the processing unit 200 by wired or wireless communication with a remote controller different from the short circuit detection device 100, then the remote controller can be used as the operation receiving unit 220.

[0143] Furthermore, in the above embodiment, the positive (+) electrode of the object to be detected 1 is connected to the connection terminal 101 of the short-circuit detection device 100, and the negative (-) electrode of the object to be detected 1 is connected to the connection terminal 102 of the short-circuit detection device 100. However, it is also possible that either the positive (+) or negative (-) electrode of the object to be detected 1, as well as the outer casing constituting the object to be detected 1, are connected to the connection terminals 101 and 102 of the short-circuit detection device 100, respectively.

[0144] Furthermore, in the above embodiment, a constant current is supplied to the object to be detected 1 and a short circuit is detected using the voltage between the two terminals of the object to be detected 1 or the current flowing through the object to be detected 1. However, this embodiment is not limited to this. Various methods can also be used to detect short circuits, such as methods that detect short circuits by measuring the voltage drop after charging the object to be detected 1 or methods that detect short circuits based on the change in current when a voltage is applied to the object to be detected 1.

[0145] Furthermore, in the above embodiment, the capacitance C of the object being tested is determined by applying an AC voltage to the object being tested and measuring the current flowing through it. However, this embodiment is not limited to this. For example, the capacitance C can also be determined by measuring the current when the object being tested is discharging, or by using an impedance bridge or dipmeter, an integration method, or a method based on the vector of the current flowing through the object being tested. Thus, various methods can be used to determine the capacitance C.

[0146] This application claims priority based on Japanese Patent Application No. 2021-098695, filed with the Japan Patent Office on June 14, 2021, and Japanese Patent Application No. 2022-095297, filed with the Japan Patent Office on June 13, 2022, the entire contents of which are incorporated herein by reference.

[0147] Explanation of reference numerals in the attached figures

[0148] 1: The object to be detected;

[0149] 10: Current limiter;

[0150] 11: Constant current source (current supply unit);

[0151] 12: Constant pressure source;

[0152] 13, 21: Switch section;

[0153] 20: Power supply for capacitance measurement (capacitance measurement unit);

[0154] 22: Current measuring section for capacitance measurement (capacitance measuring unit);

[0155] 120: Voltage measuring unit;

[0156] 130: Current measuring section (detection unit);

[0157] 140, 240: Change detection circuit (detection unit);

[0158] 150: AD converter;

[0159] 200: Processing unit (current determination unit);

[0160] 230: Storage section (storage unit).

Claims

1. A short-circuit detection device for detecting short circuits occurring in a test object, wherein, The short-circuit detection device includes: The capacitance measurement unit measures the capacitance value of the object being tested. The current determining unit determines the current value supplied to the object being detected based on the capacitance value measured by the capacitance measuring unit. A current supply unit supplies a current with the current value determined by the current determination unit to the object being detected; and The detection unit detects a short circuit in the object being detected when the current supply unit supplies the current to the object being detected.

2. The short-circuit detection device according to claim 1, wherein, The short-circuit detection device includes a storage unit, which pre-stores the detection time used by the detection unit to detect short circuits in the object being detected. The current determination unit determines the current value supplied to the object being detected based on the detection time stored in the storage unit and the capacitance value measured by the capacitance measurement unit.

3. The short-circuit detection device according to claim 1 or 2, wherein, The short-circuit detection device includes a storage unit that stores a preset current value. The current determination unit determines the current value supplied to the object being detected based on the set current value stored in the storage unit and the capacitance value measured by the capacitance measurement unit. If the set current value is below the determined current value, a short circuit of the object being detected is detected while the current of the set current value is supplied to the object being detected.

4. The short-circuit detection device according to claim 1, wherein, The larger the capacitance value, the larger the current value supplied by the current determining unit to the object being detected; the smaller the capacitance value, the smaller the current value supplied by the current determining unit to the object being detected.

5. The short-circuit detection device according to claim 2, wherein, The larger the capacitance value, the larger the current value supplied by the current determining unit to the object being detected; the smaller the capacitance value, the smaller the current value supplied by the current determining unit to the object being detected.

6. The short-circuit detection device according to claim 3, wherein, The larger the capacitance value, the larger the current value supplied by the current determining unit to the object being detected; the smaller the capacitance value, the smaller the current value supplied by the current determining unit to the object being detected.

7. The short-circuit detection device according to claim 1, wherein, The current determining unit controls the current supply unit in such a way that the value obtained by dividing the capacitance value by the current value supplied to the object being detected is constant.

8. The short-circuit detection device according to claim 1, wherein, The short-circuit detection device includes a storage unit that pre-stores an upper limit current value representing the upper limit of the current supplied to the object being detected. The current determination unit determines the current value supplied to the object being detected based on the upper limit current value stored in the storage unit and the capacitance value measured by the capacitance measurement unit. If the determined current value is greater than the upper limit current value, a short circuit of the object being detected is detected while the current of the upper limit current value is supplied to the object being detected.

9. A short-circuit detection method for detecting short circuits occurring in a test object, wherein, The short-circuit detection method includes: The capacitance measurement procedure involves measuring the capacitance value of the object being tested. The current determination step determines the current value supplied to the object being detected based on the capacitance value measured by the capacitance measurement step. The current supply step involves supplying a current with the current value determined in the current determination step to the object being detected; and The detection step involves detecting a short circuit in the object being tested while the current has been supplied to it through the current supply step.

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