CN113325260A - Fault detection device, equipment and fault detection method - Google Patents
Fault detection device, equipment and fault detection method Download PDFInfo
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Abstract
The present disclosure provides a fault detection apparatus, a device and a fault detection method. The failure detection device includes: a current transformer surrounding a power supply lead of the device under test, configured to generate an induced current in response to an alternating current in the power supply lead; a matching circuit electrically connected with the current transformer and configured to convert the induced current into a voltage signal; a detection circuit electrically connected with the matching circuit and configured to divide the voltage signal to obtain a divided voltage signal; and the judging module is electrically connected with the detection circuit and is configured to judge whether the alternating current in the power supply lead of the detected device is abnormal or not according to the voltage dividing signal. The present disclosure enables detection of whether an alternating current in a power lead of a device under test is abnormal.
Description
Technical Field
The present disclosure relates to the field of fault detection technologies, and in particular, to a fault detection apparatus, a device, and a fault detection method.
Background
In large air conditioning units, in order to make the unit operate more reliably, protective functions are generally provided for parts that are easily damaged. Particularly parts which are subjected to currents of several tens of amperes and are relatively vulnerable like compressors, require protection. For the overload condition of the compressor, the design of the related technology is to add a circuit breaker, a thermal relay and other protection devices on a power supply inlet wire of the compressor to break a main circuit to achieve the protection purpose when a fault occurs.
Disclosure of Invention
The technical problem that this disclosure solved is: a fault detection device is provided to realize the detection of equipment faults.
According to an aspect of the present disclosure, there is provided a fault detection apparatus including: a current transformer surrounding a power supply lead of a device under test, configured to generate an induced current in response to an alternating current in the power supply lead; a matching circuit electrically connected with the current transformer and configured to convert the induced current into a voltage signal; a detection circuit electrically connected with the matching circuit and configured to divide the voltage signal to obtain a divided voltage signal; and a judging module, electrically connected with the detection circuit, configured to judge whether the alternating current in the power supply lead of the detected device is abnormal according to the voltage division signal.
In some embodiments, the determining module is configured to determine that the alternating current in the power supply lead of the device under test is abnormal if the divided voltage signal is greater than a voltage threshold, and further determine that the device under test is faulty.
In some embodiments, the matching circuit comprises: the first resistor is connected with the output end of the current transformer in parallel; a rectifier sub-circuit electrically connected with the first resistor and configured to rectify a voltage across the first resistor to obtain a direct current voltage; a second resistor electrically connected to the rectifier sub-circuit; a first filtering sub-circuit electrically connected to the second resistor, configured to filter the direct current voltage and output the filtered direct current voltage to the detection circuit.
In some embodiments, the rectifier sub-circuit comprises a first diode, wherein a positive terminal of the first diode is electrically connected to the first terminal of the first resistor, and a negative terminal of the first diode is electrically connected to the first terminal of the second resistor.
In some embodiments, the first filtering sub-circuit comprises a first capacitor, wherein a first end of the first capacitor is electrically connected to a second end of the second resistor, and a second end of the first capacitor and a second end of the first resistor are both electrically connected to ground.
In some embodiments, the detection circuit comprises: a third resistor, a first end of the third resistor being electrically connected to the output end of the matching circuit, a second end of the third resistor being electrically connected to a ground end; a second filter sub-circuit, an input terminal of the second filter sub-circuit being electrically connected to the third resistor, an output terminal of the second filter sub-circuit being electrically connected to an input terminal of the judging module, the second filter sub-circuit being configured to filter the voltage-divided signal on the third resistor; and the clamping circuit is electrically connected to the input end of the judging module.
In some embodiments, the second filtering sub-circuit includes a second capacitor, a fourth resistor, and a third capacitor, wherein the second capacitor is connected in parallel with the third resistor, a first end of the fourth resistor is electrically connected to a first end of the second capacitor, a second end of the fourth resistor is electrically connected to a first end of the third capacitor, and the second end of the second capacitor and the second end of the third capacitor are both electrically connected to the ground terminal.
In some embodiments, the clamping circuit includes a second diode, wherein a positive terminal of the second diode is electrically connected to the input terminal of the determination module, and a negative terminal of the second diode is electrically connected to the power supply voltage terminal.
In some embodiments, the detection circuit further comprises: a third filter sub-circuit electrically connected between the first end of the third resistor and the ground terminal.
In some embodiments, the third filtering sub-circuit comprises a fourth capacitor.
In some embodiments, the matching circuit is provided with a first connection terminal, and the detection circuit is provided with a second connection terminal, the first connection terminal being electrically connected to the second connection terminal.
In some embodiments, the first connection terminal includes a first pin electrically connected to the second end of the second resistor and a second pin electrically connected to the ground terminal; the second connection terminal includes a third pin electrically connected to the first end of the third resistor and a fourth pin electrically connected to a ground terminal.
In some embodiments, the first pin is electrically connected to the third pin, and the second pin is electrically connected to the fourth pin.
According to another aspect of the present disclosure, there is provided an apparatus comprising: a fault detection device as hereinbefore described.
According to another aspect of the present disclosure, there is provided a fault detection method performed by the fault detection apparatus as described above, including: the current transformer generates an induced current in response to an alternating current in the power lead; the matching circuit converts the induced current into a voltage signal; the detection circuit divides the voltage signal to obtain a divided voltage signal; and the judging module judges whether the alternating current in the power supply lead of the detected equipment is abnormal or not according to the voltage dividing signal.
In some embodiments, the step of determining, by the determination module, whether the alternating current in the power supply lead of the device under test is abnormal according to the voltage division signal includes: the judgment module judges whether the voltage division signal is greater than a voltage threshold value; and determining that the alternating current in the power supply lead of the detected equipment is abnormal under the condition that the divided voltage signal is greater than the voltage threshold, and further determining that the detected equipment has a fault.
In the fault detection device, the current transformer generates an induced current in response to an alternating current in a power supply lead of the detected equipment, the matching circuit converts the induced current into a voltage signal, the detection circuit divides the voltage of the voltage signal to obtain a divided voltage signal, and the judgment module judges whether the alternating current in the power supply lead of the detected equipment is abnormal or not according to the divided voltage signal. Therefore, whether the alternating current in the power supply lead of the detected equipment is abnormal or not is detected, and further, whether the detected equipment has faults such as overload or not is detected.
Other features of the present disclosure and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description, serve to explain the principles of the disclosure.
The present disclosure may be more clearly understood from the following detailed description, taken with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram illustrating the structure of a fault detection device according to some embodiments of the present disclosure;
FIG. 2 is a circuit connection schematic diagram illustrating a fault detection device according to some embodiments of the present disclosure;
FIG. 3 is a schematic diagram showing the connection of a detection circuit according to some embodiments of the present disclosure;
fig. 4 is a flow chart illustrating a fault detection method according to some embodiments of the present disclosure.
It should be understood that the dimensions of the various parts shown in the figures are not drawn to scale. Further, the same or similar reference numerals denote the same or similar components.
Detailed Description
Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the disclosure, its application, or uses. The present disclosure may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that: the relative arrangement of parts and steps, the composition of materials, numerical expressions and numerical values set forth in these embodiments are to be construed as merely illustrative, and not as limitative, unless specifically stated otherwise.
The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element preceding the word covers the element listed after the word, and does not exclude the possibility that other elements are also covered.
In the present disclosure, when a specific device is described as being located between a first device and a second device, there may or may not be intervening devices between the specific device and the first device or the second device. When a particular device is described as being coupled to other devices, that particular device may be directly coupled to the other devices without intervening devices or may be directly coupled to the other devices with intervening devices.
All terms (including technical or scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs unless specifically defined otherwise. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.
The present disclosure provides a fault detection apparatus to realize detection of faults such as equipment overload. A fault detection device according to some embodiments of the present disclosure is described in detail below with reference to the accompanying drawings.
Fig. 1 is a schematic diagram illustrating a structure of a fault detection apparatus according to some embodiments of the present disclosure. As shown in fig. 1, the fault detection apparatus includes a current transformer 110, a matching circuit 120, a detection circuit 130, and a judgment module 140.
The current transformer 110 surrounds the power supply leads of the device under test. The current transformer 110 is configured to generate an induced current in response to an alternating current in the power leads.
The matching circuit 120 is electrically connected to the current transformer 110. The matching circuit 120 is configured to convert the induced current into a voltage signal.
The detection circuit 130 is electrically connected to the matching circuit 120. The detection circuit 130 is configured to divide the voltage signal to obtain a divided voltage signal. Through the voltage division processing, the damage of the judgment module caused by overlarge voltage signal input to the judgment module can be prevented.
The determining module 140 is electrically connected to the detecting circuit 130. The determination module 140 is configured to determine whether the alternating current in the power supply lead of the device under test is abnormal or not according to the voltage division signal. For example, the determination module includes a main chip. The main chip may be an MCU (micro controller Unit) chip.
In some embodiments, the determining module 140 may be configured to determine that the alternating current in the power supply lead of the detected device is abnormal if the divided voltage signal is greater than a voltage threshold (which may be referred to as a first voltage threshold), and further determine that the detected device is faulty. This enables fault detection of the detected device.
In other embodiments, the determination module 140 may be configured to determine that the alternating current in the power supply lead of the device under test is normal if the divided voltage signal is less than or equal to the voltage threshold.
It should be noted that the voltage threshold here can be set according to actual conditions or actual needs. The scope of the present disclosure is not limited to specific values of the voltage threshold.
To this end, a fault detection apparatus according to some embodiments of the present disclosure is provided. The fault detection device comprises a current transformer, a matching circuit, a detection circuit and a judgment module. In the fault detection device, a current transformer responds to alternating current in a power supply lead of detected equipment to generate induced current, a matching circuit converts the induced current into a voltage signal, a detection circuit divides the voltage signal to obtain a divided voltage signal, and a judgment module judges whether the alternating current in the power supply lead of the detected equipment is abnormal or not according to the divided voltage signal. Therefore, whether the alternating current in the power supply lead of the detected equipment is abnormal or not is detected, and further, whether the detected equipment has faults such as overload or not is detected.
Fig. 2 is a circuit connection schematic diagram illustrating a fault detection device according to some embodiments of the present disclosure. As shown in fig. 2, the fault detection apparatus includes a current transformer 110, a matching circuit 120, a detection circuit 130, and a judgment module 140.
In some embodiments, the current transformer 110 may be provided with a magnetic substance (e.g., a silicon steel sheet) with a strong magnetic permeability inside, which may generate a larger magnetic induction intensity in the energized coil, thereby making the volume of the transformer smaller.
The working principle of the current transformer 110 is as follows: the power lead 250 of the device to be tested (e.g., a compressor) passes through the opening 112 of the current transformer 110, and the current in the power lead of the device to be tested is an alternating current, and when the alternating current passes through the current transformer 110, an alternating electromagnetic field can be generated, and an induced electromotive force is induced on the coil of the current transformer because the coil is in the alternating electromagnetic field. The output terminals 113 and 114 of the current transformer 110 are connected to both ends of the first resistor R1 to form a loop, thereby generating an induced current.
Thus, the current transformer 110 surrounds the power supply lead 250 of the device under test. The current transformer 110 is configured to generate an induced current in response to an alternating current in the power leads.
In some embodiments, as shown in fig. 2, the matching circuit 120 may include a first resistor R1, a rectifying sub-circuit 122, a second resistor R2, and a first filtering sub-circuit 124.
A first resistor R1 is connected in parallel with the output of the current transformer 110. For example, the first resistor R1 is connected in parallel with the first output terminal 113 and the second output terminal 114 of the current transformer 110. The first resistor R1 may act as a sampling resistor.
For example, the resistance value of the first resistor R1 may be 1k Ω. Of course, those skilled in the art will appreciate that the resistance value of the first resistor R1 is merely exemplary, and the scope of the present disclosure is not so limited.
The rectifier sub-circuit 112 is electrically connected to the first resistor R1. The rectifying sub-circuit 112 is configured to rectify the voltage across the first resistor R1 to obtain a direct-current voltage. For example, the rectifier sub-circuit 112 includes a first diode D1. The positive terminal of the first diode D1 is electrically connected to the first terminal of the first resistor R1, and the negative terminal of the first diode D1 is electrically connected to the first terminal of the second resistor R2.
The second resistor R2 is electrically connected to the rectifier sub-circuit 122. For example, the resistance value of the second resistor R2 may be tens of k Ω. Of course, those skilled in the art will appreciate that the resistance value of the second resistor R2 is merely exemplary, and the scope of the present disclosure is not limited in this respect.
The first filtering subcircuit 124 is electrically connected to a second resistor R2. The first filter sub-circuit 124 is configured to filter the dc voltage and output the filtered dc voltage to the detection circuit 130. For example, the first filtering sub-circuit 124 includes a first capacitor C1. The first terminal of the first capacitor C1 is electrically connected to the second terminal of the second resistor R2, and the second terminal of the first capacitor C1 and the second terminal of the first resistor R1 are electrically connected to the ground 260. For example, the capacitance value of the first capacitor C1 ranges from 40 microfarads to 50 microfarads. Of course, those skilled in the art will appreciate that the capacitance value of the first capacitor C1 is merely exemplary, and the scope of the present disclosure is not so limited.
Thus far, the structure of the matching circuit according to some embodiments of the present disclosure has been described.
In some embodiments, as shown in fig. 2, the detection circuit 130 may include a third resistor R3, a second filtering subcircuit 132, and a clamping circuit 131.
A first end of the third resistor R3 is electrically connected to the output terminal of the matching circuit 120, and a second end of the third resistor R3 is electrically connected to the ground terminal 260. The third resistor R3 functions as a voltage dividing resistor. The third resistor can obtain a voltage division signal. The voltage is divided by the divider resistor in the detection circuit, so that the damage of the judgment module caused by the fact that the voltage value converted by the current in the matching circuit is large and exceeds the tolerance range of the judgment module can be prevented.
For example, the resistance value of the third resistor R3 may be tens of k Ω. Of course, those skilled in the art will appreciate that the resistance value of the third resistor R3 is merely exemplary, and the scope of the present disclosure is not limited thereto. The third resistor R3 can be freely matched with the second resistor R2 as long as the voltage division across the third resistor is less than the working voltage of the judgment module.
The input terminal of the second filter sub-circuit 132 is electrically connected to the third resistor R3, and the output terminal of the second filter sub-circuit 132 is electrically connected to the input terminal of the determining module 140. The second filter sub-circuit 132 is configured to filter the voltage-divided signal across the third resistor.
For example, as shown in fig. 2, the second filtering sub-circuit 132 may include a second capacitor C2, a fourth resistor R4, and a third capacitor C3. The second capacitor C2 is connected in parallel with the third resistor R3. A first end of the fourth resistor R4 is electrically connected to a first end of the second capacitor C2, and a second end of the fourth resistor R4 is electrically connected to a first end of the third capacitor C3. The second terminal of the second capacitor C2 and the second terminal of the third capacitor C3 are electrically connected to the ground terminal 260. The second filter sub-circuit 132 can filter out many interference signals, and prevent these interference signals from affecting the operation of the determination module.
For example, the resistance value of the fourth resistor R4 may be several hundred Ω, and the capacitance values of the second capacitor C2 and the third capacitor C3 may be about 0.1 microfarad, respectively. Of course, those skilled in the art will appreciate that the resistance value of the fourth resistor R4, and the capacitance values of the second capacitor C2 and the third capacitor C3 are merely exemplary, and the scope of the present disclosure is not limited thereto.
The clamp circuit 131 is electrically connected to an input terminal of the determining module 140. For example, the clamping circuit 131 includes a second diode D2. The positive terminal of the second diode D2 is electrically connected to the input terminal of the determination module 140, and the negative terminal of the second diode D2 is electrically connected to the power voltage terminal (which may be referred to as a first power voltage terminal) 270. When the voltage across the third resistor R3 is greater than the operating voltage of the determining module (e.g., the main chip), the clamping circuit 131 can clamp the voltage within the voltage range of the power voltage terminal 270, thereby protecting the determining module.
In some embodiments, the voltage of the power supply voltage terminal 270 may be the operating power supply of the determination module. For example, the voltage of the power supply voltage terminal 270 may be 3.3V or 5V, etc. Of course, those skilled in the art will appreciate that the voltage at the supply voltage terminal 270 is merely exemplary and the scope of the present disclosure is not so limited.
Thus, a structure of a detection circuit according to some embodiments of the present disclosure is provided.
In some embodiments, as shown in fig. 2, the detection circuit 130 may further include a third filtering sub-circuit 133. The third filter sub-circuit 133 is electrically connected between the first end of the third resistor R3 and the ground terminal 260. The third filter sub-circuit is matched with the second filter sub-circuit for use, so that high-frequency interference signals can be filtered, and low-frequency interference signals can also be filtered.
For example, the third filtering sub-circuit 133 may include a fourth capacitor C4. For example, the capacitance value of the fourth capacitor C4 ranges from 2.2 microfarads to 10 microfarads. Of course, those skilled in the art will appreciate that the capacitance value of the fourth capacitor C4 is merely exemplary, and the scope of the present disclosure is not limited in this respect.
In some embodiments, as shown in fig. 2, the matching circuit 120 is provided with a first connection terminal CN1, and the detection circuit 130 is provided with a second connection terminal CN2, the first connection terminal CN1 being electrically connected to the second connection terminal CN 2.
For example, the first connection terminal CN1 includes a first pin P1 and a second pin P2. The first pin P1 is electrically connected to the second end of the second resistor R2, and the second pin P2 is electrically connected to the ground terminal 260. For example, the second connection terminal CN2 includes a third pin P3 and a fourth pin P4. The third pin P3 is electrically connected to a first end of the third resistor R3, and the fourth pin P4 is electrically connected to the ground terminal 260. The first pin P1 is electrically connected to the third pin P3, and the second pin P2 is electrically connected to the fourth pin P4.
In the above embodiment, the first connection terminal CN1 is pluggably connected to the second connection terminal CN2, so that the matching circuit 120 and the detection circuit 130 can be separated or connected as required, thereby being more flexible to use.
In other embodiments, the matching circuit 120 may be directly connected to the detection circuit 130.
In the above embodiment, the fault detection apparatus shown in fig. 2 may implement a current detection function: the current transformer is used for detecting the current on the power inlet wire of the detected equipment (such as a compressor), the current transformer 110 is formed by winding a coil, and the electromagnetic induction principle can obtain the induced current at the output end of the current transformer, so that the sampling voltage can be obtained on the sampling resistor R1, and the voltage is the alternating current voltage; the dc voltage (which may be referred to as a feedback signal) may then be obtained by rectifying and filtering the matching circuit. The power supply currents of different devices to be tested correspond to different direct current voltages. Since the power supply voltage of the determination module is generally relatively fixed (for example, the power supply voltage is 3.3V or 5V), when the power supply current of the device under test is too large, the dc voltage may be larger than the power supply voltage of the determination module, and therefore, a voltage dividing resistor R3 needs to be provided. The determining module 140 directly obtains the voltage across the voltage dividing resistor R3 to determine whether the power supply current of the device under test is abnormal, so as to determine whether the device under test has a fault (e.g., an overload fault). The fault detection device has the advantages of simple structure, low cost, small detection signal error and small size, and can solve the problems of large size and high cost of circuit breakers and thermal relays in the related technology.
In some embodiments, the determining module may control the device under test to shut down when it is determined that an abnormality occurs in the alternating current in the power supply lead of the device under test. Thus, the protection of the detected equipment is realized.
Taking the detected device as a compressor as an example, if the normal operation current of the compressor is 35A and the overload current is 60A, when the current reaches 60A, the sampling voltage on the voltage dividing resistor R3 in the corresponding fault detection device is 4V. For more reliable operation of the unit, the program can be set to stop the unit in advance when the sampling voltage on the voltage dividing resistor R3 is detected to be 3.5V (assuming that the current of the compressor is 56A at the moment), so that a user can conveniently check whether the compressor is in fault or other abnormal conditions occur, and the purpose of pre-protecting the unit is achieved.
In further embodiments of the present disclosure, there is also provided an apparatus comprising a fault detection device as described above. For example, the device may be a compressor or the like.
Fig. 3 is a connection schematic diagram illustrating a detection circuit according to some embodiments of the present disclosure.
The detection circuit 130' shown in fig. 3 can be combined with the judgment module 140 to realize the detection function of the switching value. One of the differences between the detection circuit 130' shown in fig. 3 and the detection circuit 130 shown in fig. 2 is that: the fourth pin P4 of the second connection terminal CN2 is electrically connected to the second power supply voltage terminal 380. The voltage of the second power voltage terminal 380 can be selected according to actual conditions (e.g., power and load conditions in the main control board), and can be, for example, 12V or 24V.
In addition, as shown in fig. 3, the detection circuit 130 further includes a fifth resistor R5. The fifth resistor R5 is electrically connected between the input terminal (e.g., the second connection terminal CN2) of the detection circuit 130 and the first end of the third resistor R3. Alternatively, the fifth resistor R5 may include a plurality of sub-resistors arranged in parallel. For example, as shown in fig. 3, the fifth resistor R5 may include a first sub-resistor R51 and a second sub-resistor R52 arranged in parallel. By arranging the fifth resistor in parallel with the sub-resistors, the number and size of the parallel sub-resistors can be set as desired, thereby setting the size of the fifth resistor. The fifth resistor R5 has both a voltage dividing function and a function of protecting a subsequent circuit.
It should be noted that the resistance values of the first sub-resistor R51 and the second sub-resistor R52 depend on the voltage of the second power voltage terminal, as long as the voltage obtained by the third resistor R3 is smaller than the operating voltage of the determination module after the first sub-resistor R51 and the second sub-resistor R52 are connected in parallel and then connected in series with the third resistor R3. For example, the resistance values of the first sub-resistor R51 and the second sub-resistor R52 may be about ten and several k Ω, respectively. Of course, it will be understood by those skilled in the art that the resistance values of the first and second sub-resistors described above are merely exemplary, and the scope of the present disclosure is not limited thereto.
The principle of the switching value detection is described below: as shown in fig. 3, the two pins P3 and P4 of the second connection terminal CN2 are electrically connected to two ends of a switch K, respectively, when the switch K is closed, since the fourth pin P4 of the second connection terminal CN2 is electrically connected to the second power voltage terminal 380, the third resistor R3, as a voltage dividing resistor, can obtain a voltage dividing signal, which is transmitted to the judgment module 140, which determines that the switch K is closed when the voltage dividing signal is greater than the second voltage threshold; when the switch K is opened, the third resistor does not obtain a voltage division signal, which can be regarded as 0, and therefore the judging module determines that the switch K is opened under the condition that the voltage division signal is less than or equal to the second voltage threshold. Thus, the circuit shown in fig. 3 realizes the detection of the switching value.
It should be noted that the second voltage threshold may be determined according to actual conditions or actual needs. The scope of the present disclosure is not limited to a specific value of the second voltage threshold.
The detection circuit may be designed as a detection circuit shown in fig. 2 or a detection circuit shown in fig. 3 as needed, and therefore, the detection circuit may use a current detection function (i.e., a fault detection function) and a switching value detection function in a compatible manner, and may save an I/O (input/output) port of an MCU chip (i.e., a determination module).
Fig. 4 is a flow chart illustrating a fault detection method according to some embodiments of the present disclosure. As shown in fig. 4, the method includes steps S402 to S408.
In step S402, the current transformer generates an induced current in response to the alternating current in the power supply lead.
In step S404, the matching circuit converts the induced current into a voltage signal.
In step S406, the detection circuit divides the voltage signal to obtain a divided voltage signal.
In step S408, the determination module determines whether the alternating current in the power supply lead of the device under test is abnormal or not according to the divided voltage signal.
In some embodiments, this step S408 includes: the judgment module judges whether the voltage division signal is greater than a voltage threshold value; and determining that the alternating current in the power supply lead of the detected equipment is abnormal under the condition that the divided voltage signal is greater than the voltage threshold, and further determining that the detected equipment has a fault.
Thus, a fault detection method according to some embodiments of the present disclosure is provided. In the detection method, a current transformer generates an induced current in response to an alternating current in a power supply lead; the matching circuit converts the induced current into a voltage signal; the detection circuit divides the voltage signal to obtain a divided voltage signal; and the judging module judges whether the alternating current in the power supply lead of the detected equipment is abnormal or not according to the voltage dividing signal. Therefore, whether the alternating current in the power supply lead of the detected equipment is abnormal or not is detected, and further, whether the detected equipment has faults such as overload or not is detected.
Thus, various embodiments of the present disclosure have been described in detail. Some details that are well known in the art have not been described in order to avoid obscuring the concepts of the present disclosure. It will be fully apparent to those skilled in the art from the foregoing description how to practice the presently disclosed embodiments.
Although some specific embodiments of the present disclosure have been described in detail by way of example, it should be understood by those skilled in the art that the foregoing examples are for purposes of illustration only and are not intended to limit the scope of the present disclosure. It will be understood by those skilled in the art that various changes may be made in the above embodiments or equivalents may be substituted for elements thereof without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.
Claims (16)
1. A fault detection device comprising:
a current transformer surrounding a power supply lead of a device under test, configured to generate an induced current in response to an alternating current in the power supply lead;
a matching circuit electrically connected with the current transformer and configured to convert the induced current into a voltage signal;
a detection circuit electrically connected with the matching circuit and configured to divide the voltage signal to obtain a divided voltage signal; and
and the judging module is electrically connected with the detection circuit and is configured to judge whether the alternating current in the power supply lead of the detected device is abnormal or not according to the voltage dividing signal.
2. The fault detection device of claim 1,
the judging module is configured to determine that the alternating current in the power supply lead of the detected device is abnormal when the divided voltage signal is greater than a voltage threshold, and further determine that the detected device is in failure.
3. The fault detection device of claim 1, wherein the matching circuit comprises:
the first resistor is connected with the output end of the current transformer in parallel;
a rectifier sub-circuit electrically connected with the first resistor and configured to rectify a voltage across the first resistor to obtain a direct current voltage;
a second resistor electrically connected to the rectifier sub-circuit;
a first filtering sub-circuit electrically connected to the second resistor, configured to filter the direct current voltage and output the filtered direct current voltage to the detection circuit.
4. The fault detection device of claim 3,
the rectifier sub-circuit comprises a first diode, wherein the positive end of the first diode is electrically connected to the first end of the first resistor, and the negative end of the first diode is electrically connected to the first end of the second resistor.
5. The fault detection device of claim 4,
the first filtering sub-circuit comprises a first capacitor, wherein a first end of the first capacitor is electrically connected to a second end of the second resistor, and the second end of the first capacitor and the second end of the first resistor are both electrically connected to a ground terminal.
6. The fault detection device of claim 5, wherein the detection circuit comprises:
a third resistor, a first end of the third resistor being electrically connected to the output end of the matching circuit, a second end of the third resistor being electrically connected to the ground end;
a second filter sub-circuit, an input terminal of the second filter sub-circuit being electrically connected to the third resistor, an output terminal of the second filter sub-circuit being electrically connected to an input terminal of the judging module, the second filter sub-circuit being configured to filter the voltage-divided signal on the third resistor; and
and the clamping circuit is electrically connected to the input end of the judging module.
7. The fault detection device of claim 6,
the second filter sub-circuit comprises a second capacitor, a fourth resistor and a third capacitor, wherein the second capacitor is connected with the third resistor in parallel, a first end of the fourth resistor is electrically connected to a first end of the second capacitor, a second end of the fourth resistor is electrically connected to a first end of the third capacitor, and the second end of the second capacitor and the second end of the third capacitor are both electrically connected to the ground terminal.
8. The fault detection device of claim 6,
the clamping circuit comprises a second diode, wherein the positive electrode end of the second diode is electrically connected to the input end of the judging module, and the negative electrode end of the second diode is electrically connected to the power supply voltage end.
9. The fault detection device of claim 6, wherein the detection circuit further comprises:
a third filter sub-circuit electrically connected between the first end of the third resistor and the ground terminal.
10. The fault detection device of claim 9,
the third filtering sub-circuit comprises a fourth capacitor.
11. The fault detection device of claim 6,
the matching circuit is provided with a first connection terminal, the detection circuit is provided with a second connection terminal, and the first connection terminal is electrically connected to the second connection terminal.
12. The fault detection device of claim 11,
the first connection terminal includes a first pin electrically connected to the second end of the second resistor and a second pin electrically connected to the ground terminal;
the second connection terminal includes a third pin electrically connected to the first end of the third resistor and a fourth pin electrically connected to the ground terminal.
13. The fault detection device of claim 12,
the first pin is electrically connected to the third pin, and the second pin is electrically connected to the fourth pin.
14. An apparatus, comprising: a fault detection device according to any one of claims 1 to 13.
15. A fault detection method performed with the fault detection apparatus of any one of claims 1 to 13, comprising:
the current transformer generates an induced current in response to an alternating current in the power lead;
the matching circuit converts the induced current into a voltage signal;
the detection circuit divides the voltage signal to obtain a divided voltage signal; and
and the judging module judges whether the alternating current in the power supply lead of the detected equipment is abnormal or not according to the voltage dividing signal.
16. The fault detection method according to claim 15, wherein the step of determining, by the determination module, whether the alternating current in the power supply lead of the device under test is abnormal or not, based on the divided voltage signal, comprises:
the judgment module judges whether the voltage division signal is greater than a voltage threshold value; and
and determining that the alternating current in the power supply lead of the detected equipment is abnormal under the condition that the divided voltage signal is greater than the voltage threshold, and further determining that the detected equipment has a fault.
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Cited By (1)
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CN114857739A (en) * | 2022-03-11 | 2022-08-05 | 青岛海尔空调器有限总公司 | Method and device for identifying air conditioner fault component, air conditioner and storage medium |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN114857739A (en) * | 2022-03-11 | 2022-08-05 | 青岛海尔空调器有限总公司 | Method and device for identifying air conditioner fault component, air conditioner and storage medium |
CN114857739B (en) * | 2022-03-11 | 2024-05-24 | 青岛海尔空调器有限总公司 | Method and device for identifying air conditioner fault component, air conditioner and storage medium |
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