Fault detection circuit and intelligent socket

Abstract

The utility model relates to the technical field of electronic circuits, and mainly provides a fault detection circuit and an intelligent socket, the circuit comprises a control module, a relay RLY1 and a fault detection module; the control module is connected with a coil end of the relay RLY1, a common end of the relay RLY1 is connected with a power supply, the fault detection module is connected with a normally open end of the relay RLY1, and the fault detection module and the control module are both used for receiving driving signals; when the driving signal is a first signal, the control module is used for controlling the coil end of the relay RLY1 to be electrified; meanwhile, the fault detection module is used for judging whether a voltage signal output by the power supply is received through the relay RLY1 or not so as to determine whether the relay RLY1 switches the connection state or not, and when the voltage signal is not received, it is determined that the relay RLY1 breaks down, and then a fault signal is output. After the fault detection module outputs the fault signal, the output of the power supply can be cut off according to the fault signal, thereby avoiding safety accidents, and further improving the safety of the intelligent socket.

Description

[Technical Field]

[0001] This utility model relates to the technical field of electronic circuits, and in particular to a fault detection circuit and a smart socket. [Background Technology]

[0002] With the proliferation of smart hardware devices, smart sockets, as a simple and practical smart product, have been widely adopted. During use, smart sockets primarily utilize the electromagnetic effect of relays to control the connection and disconnection of the circuit.

[0003] Most smart sockets on the market use normally open relays. However, in critical loads such as ventilators and refrigerators, if the smart socket malfunctions (either due to a faulty control chip or a faulty relay), the relay may remain in the normally open state, causing the load to lose power.

[0004] Furthermore, if a smart socket malfunctions at the same time as an overload, it can lead to a safety accident. Existing smart sockets on the market cannot provide timely and effective protection, causing further damage to the load and creating safety risks. [Utility Model Content]

[0005] This utility model provides a fault detection circuit and a smart socket, aiming to solve the problem of low security in existing smart sockets.

[0006] To solve the above-mentioned technical problems, one technical solution adopted by this utility model is: to provide a fault detection circuit, the fault detection circuit including a control module, a relay RLY1 and a fault detection module;

[0007] The control module is connected to the coil terminal of the relay RLY1, the common terminal of the relay RLY1 is connected to the power supply, the fault detection module is connected to the normally open terminal of the relay RLY1, and both the fault detection module and the control module are used to receive drive signals.

[0008] The control module is used to control the coil terminal of the relay RLY1 to be energized when the drive signal is the first signal;

[0009] The fault detection module is used to determine whether the voltage signal output by the power supply is received through the relay RLY1 when the drive signal is the first signal, and to output a fault signal when the voltage signal is not received.

[0010] Optionally, the fault detection circuit may further include a protection module;

[0011] The protection module is connected to the fault detection module, and the protection module is also connected to the normally closed terminal of the relay RLY1 and the load respectively.

[0012] The protection module is used to cut off the voltage signal output by the power supply through the relay RLY1 after receiving the fault signal.

[0013] Optionally, the fault detection module includes a detection unit and a comparison unit;

[0014] The detection unit is connected to the normally open terminal of the relay RLY1 and the second input terminal of the comparison unit, respectively. The output terminal of the comparison unit is connected to the protection module. The first input terminal of the comparison unit is used to receive the drive signal.

[0015] The detection unit is used to detect the output voltage of the normally open terminal of the relay RLY1 in real time, and input the output voltage to the second input terminal of the comparison unit;

[0016] The comparison unit is used to determine whether the output voltage is less than the driving voltage corresponding to the first signal when the driving signal is the first signal, so as to determine whether the relay RLY1 is disconnected, and to output a fault signal when the output voltage is less than the driving voltage.

[0017] Optionally, the detection unit includes resistor R8, resistor R7, Zener diode D2, and capacitor C2;

[0018] The resistor R8 is connected to the normally open terminal of the relay RLY1 and the anode of the Zener diode D2, respectively. The resistor R7 is connected in series with the resistor R8 and is also used for grounding. The cathode of the Zener diode D2 is connected to the capacitor C2 and the comparator unit, respectively. The capacitor C2 is also used for grounding.

[0019] Optionally, the comparison unit includes a comparator U1B and a pull-up resistor R9;

[0020] The non-inverting input of the comparator U1B is used to receive the driving signal, the inverting input of the comparator U1B is connected to the detection unit, the output of the comparator U1B is connected to the first power supply through the pull-up resistor R9, and the output of the comparator U1B is used to connect to the protection module.

[0021] Optionally, the control module includes resistors R5 and R6 and a switching transistor Q1;

[0022] The control terminal of the switch Q1 receives the drive signal through the resistor R5. The control terminal of the switch Q1 is also connected to the second terminal of the switch Q1 through the resistor R6. The first terminal of the switch Q1 is connected to the coil terminal of the relay RLY1. The second terminal of the switch Q1 is used for grounding.

[0023] Optionally, the protection module includes a control unit and a relay RLY2;

[0024] The control unit is connected to the fault detection module, and the control unit is also connected to the coil terminal of the relay RLY2. The connection terminal of the relay RLY2 is connected to the normally closed terminal of the relay RLY1 and the load, respectively.

[0025] The control unit is used to energize the relay RLY2 after receiving the fault signal, thereby disconnecting the power supply from the load.

[0026] Optionally, the protection module further includes a light-emitting diode (LED1);

[0027] The anode of the LED1 is connected to the fault detection module, and the cathode of the LED1 is connected to the control unit.

[0028] Optionally, the fault detection circuit further includes a zero-crossing detection module;

[0029] The zero-crossing detection module is connected to the control module and is also connected to the power supply. The zero-crossing detection module is also used to receive control signals.

[0030] The zero-crossing detection module is used to detect the instantaneous voltage of the power supply, and when the instantaneous voltage is less than the first preset voltage, it outputs a corresponding drive signal to the control module according to the control signal, so that the relay RLY1 completes the switching action when the instantaneous voltage is less than the second preset voltage, wherein the second preset voltage is less than the first preset voltage.

[0031] To solve the above-mentioned technical problems, another technical solution adopted in this utility model embodiment is to provide a smart socket, which includes the fault detection circuit described above.

[0032] Unlike related technologies, this utility model provides a fault detection circuit and a smart socket. The fault detection circuit includes a control module, a relay RLY1, and a fault detection module. The control module is connected to the coil terminal of the relay RLY1, and the common terminal of the relay RLY1 is connected to a power supply. The fault detection module is connected to the normally open terminal of the relay RLY1. Both the fault detection module and the control module are used to receive drive signals. When the drive signal is a first signal, the control module controls the coil terminal of the relay RLY1 to be energized, so that the relay RLY1 switches its connection state according to the first signal. When the drive signal is the first signal, the fault detection module determines whether a voltage signal output from the power supply is received through the relay RLY1 to determine whether the relay RLY1 has switched its connection state. If the voltage signal is not received, it determines that the relay RLY1 has not switched its connection state, thereby determining that the relay RLY1 has malfunctioned and outputting a fault signal. After the fault detection module outputs a fault signal, the power supply output can be cut off according to the fault signal to avoid safety accidents, thus improving the safety and stability of the smart socket. [Attached Image Description]

[0033] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0034] Figure 1 This is a schematic diagram of an application scenario provided by an embodiment of this utility model;

[0035] Figure 2 This is a structural block diagram of a fault detection circuit provided in an embodiment of the present utility model;

[0036] Figure 3 This is a circuit diagram of a control module provided in an embodiment of the present utility model;

[0037] Figure 4 This is a circuit diagram of a fault detection circuit provided in an embodiment of the present invention;

[0038] Figure 5 This is a structural block diagram of a fault detection circuit provided in another embodiment of the present invention;

[0039] Figure 6 This is a circuit diagram of the zero-crossing detection module provided in this embodiment of the utility model;

[0040] Figure 7This is a circuit diagram of a fault detection circuit provided in another embodiment of the present invention.

Detailed Implementation Methods

[0041] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0042] The technical features involved in the various embodiments of this application described below do not conflict with each other and can be combined with each other.

[0043] When an element is described as "connected" to another element, it can be directly connected to the other element, or there may be one or more intervening elements between them.

[0044] The terms "first," "second," etc., used in the specification and claims of this utility model are used to distinguish similar objects and are not used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, the first object can be one or more.

[0045] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0046] Please see Figure 1 , Figure 1 This is a schematic diagram of an application scenario provided by an embodiment of this utility model, such as... Figure 1 As shown, this application scenario 1 includes a power supply 100, a smart socket 200, and a load 300; the power supply 100 supplies power to the load 300 through the smart socket 200. Wherein, as... Figure 1 As shown, the smart socket 200 includes a fault detection circuit 10 and a controller 20. The fault detection circuit 10 is connected to the power supply 100 and the load 300 respectively. The fault detection circuit 10 is also connected to the controller 20. The controller 20 is used to output a drive signal to the fault detection circuit 10 and control the working state of the fault detection circuit 10 based on the drive signal.

[0047] In some embodiments, such as Figure 1 As shown, the controller 20 is also connected to the load 300. The controller 20 is used to detect the working status of the load 300 in real time, and output the corresponding drive signal in real time according to the working status of the load 300, and control the working status of the fault detection circuit 10 according to the drive signal.

[0048] Please see Figure 2 , Figure 2 This is a structural block diagram of a fault detection circuit provided in an embodiment of the present invention, as shown below. Figure 2 As shown, the fault detection circuit 10 includes a control module 11, a relay RLY1, and a fault detection module 12;

[0049] The control module 11 is connected to the coil terminal of the relay RLY1, the common terminal of the relay RLY1 is connected to the power supply 100, the fault detection module 12 is connected to the normally open terminal of the relay RLY1, and both the fault detection module 12 and the control module 11 are used to receive drive signals.

[0050] The control module 11 is used to control the coil terminal of the relay RLY1 to be energized when the driving signal is the first signal;

[0051] The fault detection module 12 is used to determine whether the voltage signal output by the power supply 100 is received through the relay RLY1 when the drive signal is the first signal, and to output a fault signal when the voltage signal is not received.

[0052] Specifically, when the power supply 100 supplies power to the load 300 through the fault detection circuit 10, the normally closed terminal of the relay RLY1 is connected to the load 300. At this time, if the control module 11 receives a drive signal output by the controller 20, and the drive signal is the first signal, it will control the coil terminal of the relay RLY1 to be energized, thereby causing the relay RLY1 to switch to connection with the fault detection module 12 (i.e., the relay RLY1 switches from a normally closed terminal to a normally open terminal). If the drive signal is the second signal, the relay RLY1 remains connected to the load 300.

[0053] It is understood that when the driving signal is the first signal, the relay RLY1 will switch to connect with the fault detection module 12, and therefore the fault detection module 12 will detect the voltage signal output by the power supply 100. When the fault detection module 12 detects the voltage signal, it considers that the relay RLY1 has switched normally according to the driving signal, thus determining that the relay RLY1 is fault-free. However, if the fault detection module 12 does not detect the voltage signal output by the relay RLY1, it considers that the relay RLY1 has not switched its connection state, and in this case, the fault detection module 12 will output a fault signal.

[0054] It should be noted that since the normally closed terminal of the relay RLY1 is connected to the load 300, when the relay RLY1 fails, the power supply 100 can still supply power to the load 300 through the relay RLY1, thereby ensuring that the load 300 is in an uninterrupted power supply state when the load 300 is an important load (such as a ventilator and a refrigerator).

[0055] In some embodiments, please refer to Figure 3 , Figure 3 This is a circuit diagram of a control module provided in an embodiment of the present invention, such as... Figure 3 As shown, the control module 11 includes resistors R5 and R6 and a switching transistor Q1;

[0056] The control terminal of the switch Q1 receives the drive signal (RLY-L) through the resistor R5. The control terminal of the switch Q1 is also connected to the second terminal of the switch Q1 through the resistor R6. The first terminal of the switch Q1 is connected to the coil terminal of the relay RLY1. The second terminal of the switch Q1 is used for grounding.

[0057] When the controller 20 outputs a drive signal, if the drive signal is the first signal, the switch Q1 will be turned on according to the drive signal, thereby grounding the coil terminal of the relay RLY1 through the switch Q1, and energizing the coil terminal of the relay RLY1. At this time, the relay RLY1 will switch to be connected to the fault detection module 12 (that is, the relay RLY1 will switch from being connected to pin 4 to being connected to pin 5), thereby stopping the power supply to the load 300. However, if the drive signal is the second signal, the switch Q1 will be in the off state, thereby keeping the relay RLY1 connected to the load 300.

[0058] In some embodiments, such as Figure 3As shown, the control module 11 also includes an anti-reverse current diode D1. The cathode of the anti-reverse current diode D1 is connected to the control terminal of the switching transistor Q1 through a resistor R5, and the anode of the anti-reverse current diode D1 is connected to the controller 20. The anti-reverse current diode D1 is used to prevent the voltage at the coil terminal of the relay RLY1 from flowing back to the controller 20 through the switching transistor Q1 when the switching transistor Q1 is turned on.

[0059] Furthermore, such as Figure 2 As shown, the fault detection circuit 10 also includes a protection module 13;

[0060] The protection module 13 is connected to the fault detection module 12, and the protection module 13 is also connected to the normally closed terminal of the relay RLY1 and the load 300 respectively.

[0061] The protection module 13 is used to cut off the voltage signal output by the power supply 100 through the relay RLY1 after receiving the fault signal.

[0062] In some embodiments, when the load 300 malfunctions (e.g., overload), the controller 20 detects the malfunction of the load 300 and outputs a corresponding drive signal to the control module 11 based on the malfunction, causing the relay RLY1 to switch to the normally open state, thereby stopping power supply to the load 300. It should be noted that if the relay RLY1 also malfunctions when the load 300 malfunctions, the power supply 100 will continue to supply power to the load 300 through the relay RLY1, creating a safety hazard. Therefore, this application provides a protection module 13 between the normally closed terminal of the relay RLY1 and the load 300. This module cuts off the output of the relay RLY1 based on the fault signal output by the fault detection module 12, thereby stopping the power supply 100 from supplying power to the load 300 and improving the safety of the smart socket.

[0063] In some embodiments, such as Figure 2 As shown, the fault detection module 12 includes a detection unit 121 and a comparison unit 122;

[0064] The detection unit 121 is connected to the normally open terminal of the relay RLY1 and the second input terminal of the comparison unit 122, respectively. The output terminal of the comparison unit 122 is connected to the protection module 13. The first input terminal of the comparison unit 122 is used to receive the drive signal.

[0065] The detection unit 121 is used to detect the output voltage of the normally open terminal of the relay RLY1 in real time, and input the output voltage to the second input terminal of the comparison unit 122;

[0066] The comparison unit 122 is used to determine whether the output voltage is less than the driving voltage corresponding to the first signal when the driving signal is the first signal, so as to determine whether the relay RLY1 is disconnected, and to output a fault signal when the output voltage is less than the driving voltage.

[0067] Specifically, during the operation of the fault detection circuit 10, the detection unit 121 continuously monitors the output voltage of the normally open terminal of the relay RLY1 and inputs the output voltage to the second input terminal of the comparison unit 122. Simultaneously, the first input terminal of the comparison unit 122 receives the drive signal output by the controller 20, determines the magnitude of the drive voltage corresponding to the drive signal and the output voltage of the normally open terminal of the relay RLY1, and outputs a corresponding signal to the protection module 13 based on the comparison result. It should be noted that when the drive signal is the first signal, if the voltage at the first input terminal of the comparison unit 122 is less than the voltage at the second input terminal, the comparison unit 122 will output a normal signal to indicate that the relay RLY1 is switching normally. However, if the voltage at the first input terminal of the comparison unit 122 is greater than the voltage at the second input terminal, the comparison unit 122 will output a fault signal to the protection module 13, indicating that the relay RLY1 has malfunctioned.

[0068] In some other embodiments, please refer to Figure 4 , Figure 4 This is a circuit diagram of a fault detection circuit provided in an embodiment of this utility model, as shown below. Figure 4 As shown, the detection unit 121 includes resistors R8 and R7, a Zener diode D2, and a capacitor C2; the comparison unit 122 includes a comparator U1B and a pull-up resistor R9.

[0069] The resistor R8 is connected to the normally open terminal of the relay RLY1 and the anode of the Zener diode D2, respectively. The resistor R7 is connected in series with the resistor R8 and is also used for grounding. The cathode of the Zener diode D2 is connected to the capacitor C2 and the comparator unit 122, respectively. The capacitor C2 is also used for grounding.

[0070] The non-inverting input of the comparator U1B is used to receive the driving signal, the inverting input of the comparator U1B is connected to the detection unit 121, the output of the comparator U1B is connected to the first power supply 50 through the pull-up resistor R9, and the output of the comparator U1B is used to connect to the protection module 13.

[0071] Specifically, when the power supply 100 supplies power to the load 300, resistors R7 and R8 continuously acquire the output voltage of the normally open terminal of relay RLY1, divide the output voltage, and input the divided output voltage to the inverting input of comparator U1B. Upon receiving the divided output voltage, the inverting input of comparator U1B compares it with the driving voltage corresponding to the driving signal. If the driving signal is the first signal and the divided output voltage is greater than the driving voltage, comparator U1B outputs a normal signal, indicating that relay RLY1 is switching its connection state normally according to the driving signal. If the driving signal is the first signal and the divided output voltage is less than the driving voltage, comparator U1B outputs a high-level signal (fault signal).

[0072] In yet another embodiment, such as Figure 2 As shown, the protection module 13 includes a control unit 131 and a relay RLY2;

[0073] The control unit 131 is connected to the fault detection module 12. The control unit 131 is also connected to the coil terminal of the relay RLY2. The connection terminal of the relay RLY2 is connected to the normally closed terminal of the relay RLY1 and the load 300, respectively.

[0074] The control unit 131 is used to energize the relay RLY2 after receiving the fault signal, thereby disconnecting the power supply 100 from the load 300.

[0075] It should be noted that the normally closed terminal of relay RLY2 is connected to the load 300, and the normally open terminal of relay RLY2 is connected to the discharge port. When the load 300 is functioning correctly and relay RLY1 can switch normally, the voltage signal from the power supply 100 is input to the load 300 through the normally closed terminals of relays RLY1 and RLY2 to supply power to the load 300. When it is necessary to disconnect the power supply circuit between the power supply 100 and the load 300, if relay RLY1 fails, relay RLY2 can be switched to its normally open terminal to disconnect the power supply circuit of the power supply 100, thereby improving the safety of the smart socket 200.

[0076] Specifically, when the relay RLY1 malfunctions, the fault detection module 12 will output a fault signal to the control unit 131. When the control unit 131 receives the fault signal, it will control the coil terminal of the relay RLY2 to be energized based on the fault signal, thereby switching the relay RLY2 to be connected to the discharge port to discharge the voltage signal of the power supply 100, thereby disconnecting the power supply circuit of the power supply 100.

[0077] Furthermore, such as Figure 4 As shown, the control unit 131 includes a resistor R11, a capacitor C3, and a switching transistor Q2;

[0078] The control terminal of the switch Q2 is connected to the fault detection module 12. The control terminal of the switch Q2 is also connected to the second terminal of the switch Q2 through the resistor R11. The capacitor C3 is connected in parallel with the resistor R11. The first terminal of the switch Q2 is connected to the coil terminal of the relay RLY2. The second terminal of the switch Q2 is also used for grounding.

[0079] When the fault detection module 12 outputs a fault signal, the switching transistor Q2 will conduct based on the fault signal, thereby forming a circuit at the coil terminal of the relay RLY2, that is, the coil terminal of the relay RLY2 will be energized. At this time, the relay RLY2 will switch its connection state, thereby cutting off the power supply circuit of the power supply 100.

[0080] In some embodiments, such as Figure 4 As shown, the protection module 13 also includes a light-emitting diode (LED) 1;

[0081] The anode of the LED1 is connected to the fault detection module 12, and the cathode of the LED1 is connected to the control unit 131. When the fault detection module 12 outputs a fault signal, the LED1 will illuminate to alert the user that the smart socket 200 has malfunctioned, thereby improving the security of the smart socket.

[0082] In another embodiment, the LED1 is also connected to the controller 20. When the LED1 issues an alarm based on the fault signal, the fault signal (M-LEDN-O) is also input to the controller 20 so that the user is informed by the controller 20 that the smart socket has malfunctioned, thereby improving the security of the smart socket.

[0083] In another embodiment, such as Figure 4As shown, the protection module 13 also includes a resettable fuse F1, which is connected to the normally closed terminal of the relay RLY2 and the load 300 respectively. The resettable fuse F1 is used to blow when all modules in the fault detection circuit fail, so as to provide physical protection for the smart socket.

[0084] In some embodiments, please refer to Figure 5 , Figure 5 This is a structural block diagram of a fault detection circuit provided in another embodiment of the present invention, as shown below. Figure 5 As shown, the fault detection circuit 10 also includes a zero-crossing detection module 14;

[0085] The zero-crossing detection module 14 is connected to the control module 11, and the zero-crossing detection module 14 is also connected to the power supply 100. The zero-crossing detection module 14 is also used to receive control signals.

[0086] The zero-crossing detection module 14 is used to detect the instantaneous voltage of the power supply 100, and when the instantaneous voltage is less than the first preset voltage, it outputs a corresponding drive signal to the control module 11 according to the control signal, so that the relay RLY1 completes the switching action when the instantaneous voltage is less than the second preset voltage, wherein the second preset voltage is less than the first preset voltage.

[0087] It should be noted that since the voltage signal output by the power supply 100 is alternating current (AC), and AC voltage changes over time, if the relay RLY1 switches its connection state when the power supply 100 is in a high-voltage state while supplying power to the load 300, it will cause arcing in the relay RLY1, potentially leading to a safety accident. Therefore, the zero-crossing detection module 14 monitors the instantaneous voltage of the power supply 100 in real time. When the instantaneous voltage is lower than a first preset voltage, a drive signal is output to the control module 11. This allows the control module 11 to control the relay RLY1 to switch its connection state when the instantaneous voltage is lower than a second preset voltage, ensuring that the relay RLY1 switches its connection state under low voltage conditions to avoid arcing.

[0088] Furthermore, such as Figure 5 As shown, the zero-crossing detection module 14 includes a detection and judgment unit 141 and a trigger unit 142. The detection and judgment unit 141 is connected to the trigger unit 142 and the power supply 100 respectively. The trigger unit 142 is connected to the control module 11 and is also used to receive control signals.

[0089] When the power supply 100 supplies power to the load 300, the detection and judgment unit 141 detects the instantaneous voltage of the power supply 100 in real time. When the instantaneous voltage is greater than a first preset voltage, it outputs a low-level signal to the trigger unit 142; when the instantaneous voltage is less than the first preset voltage, it outputs a high-level signal to the trigger unit 142. At the instant the trigger unit 142 receives the high-level signal, it outputs a drive signal to the control module 11 according to the control signal output by the controller 20, so that the control module 11 controls the connection state of the relay RLY1 according to the drive signal. When the trigger unit 142 receives the low-level signal or continuously receives the high-level signal, it maintains the drive signal output to the control module 11 to maintain the current connection state of the relay RLY1.

[0090] Please see Figure 6 , Figure 6 This is a circuit diagram of the zero-crossing detection module provided in this embodiment of the utility model, as shown below. Figure 6 As shown, the detection and judgment unit 141 includes resistors R1 and R2 and comparator U1A; the trigger unit 142 includes trigger U1 and pull-up resistor R4;

[0091] The resistor R1 is connected to the power supply 100 (IN-L) and the second input terminal of the comparator U1A respectively. The resistor R1 is also connected in series with the resistor R2. The resistor R2 is also used for grounding. The first input terminal of the comparator U1A is used to receive the reference voltage. The output terminal of the comparator U1A is connected to the trigger unit 142.

[0092] The clock input terminal of the flip-flop U1 is connected to the output terminal of the comparator U1A. The clear data terminal of the flip-flop U1 is connected to the second power supply 51 through the pull-up resistor R4. The signal input terminal of the flip-flop U1 is used to receive the control signal (SCL). The output terminal of the flip-flop U1 is connected to the control module 11.

[0093] When the power supply 100 supplies power to the load 300, resistors R1 and R2 continuously acquire the instantaneous voltage of the power supply 100, divide the instantaneous voltage, and input the divided instantaneous voltage to the second input terminal (inverting input terminal) of the comparator U1A. When the comparator U1A receives the divided instantaneous voltage, it compares it with the reference voltage. If the divided instantaneous voltage is less than the reference voltage, it is considered less than a first preset voltage, and the comparator U1A outputs a high-level signal. If the divided instantaneous voltage is greater than the reference voltage, it is considered greater than the first preset voltage, and the comparator U1A outputs a low-level signal. Since the voltage signal output by the power supply 100 changes continuously over time, the output of the comparator U1A also continuously switches between high and low level signals.

[0094] It should be noted that the trigger U1 is a monostable trigger. Only when the clear data terminal of the trigger U1 receives a high level will the trigger U1 output the corresponding drive signal according to the control signal at the signal input terminal at the instant the high-level signal is received. Therefore, at the instant the comparator U1A outputs a high-level signal, the trigger U1 will output the corresponding drive signal according to the state of the control signal. For example, if the control signal is the first signal, then the drive signal is also the first signal, and the relay RLY1 will switch its connection state according to the drive signal.

[0095] In some embodiments, please refer to Figure 7 , Figure 7 This is a circuit diagram of a fault detection circuit provided in another embodiment of this utility model, such as... Figure 7As shown, when the power supply 100 supplies power to the load 300, the comparator U1A outputs a high-level signal to the trigger U1 when the instantaneous voltage is less than the first preset voltage. Upon receiving the high-level signal, the trigger U1 outputs a corresponding drive signal to the switch Q1 according to the control signal output by the controller 20. If the controller 20 needs to disconnect the power supply circuit of the power supply 100, the control signal is the first signal. After receiving the first signal, the switch Q1 controls the relay RLY1 to switch its connection state when the instantaneous voltage is less than the second preset voltage. If the relay RLY1 is normal, the voltage at the inverting input of the comparator U1B will be greater than the voltage at the non-inverting input, thus outputting a low-level signal (normal signal). At this time, the LED1 is not lit, and the switch Q2 is in the off state. If relay RLY1 malfunctions, it will not switch its connection state. The voltage at the inverting input of comparator U1B will be lower than the voltage at the non-inverting input, causing comparator U1B to output a high-level signal (fault signal). At this time, LED1 will light up according to the high-level signal, and switch Q2 will also turn on based on the high-level signal. When switch Q2 turns on, relay RLY2 is energized and switches to the normally open state, thus stopping power supply to load 300. Based on this, relay malfunction can be detected in real time according to the drive signal. Furthermore, the protection module can prevent the power supply from continuously supplying power to the load when both the load and the relay malfunction, thereby improving the safety of the smart socket.

[0096] This utility model embodiment provides a fault detection circuit, which includes a control module, a relay RLY1, and a fault detection module. The control module is connected to the coil terminal of the relay RLY1, and the common terminal of the relay RLY1 is connected to a power supply. The fault detection module is connected to the normally open terminal of the relay RLY1. Both the fault detection module and the control module are used to receive drive signals. When the drive signal is a first signal, the control module controls the coil terminal of the relay RLY1 to be energized, so that the relay RLY1 switches its connection state according to the first signal. When the drive signal is the first signal, the fault detection module determines whether a voltage signal output from the power supply is received through the relay RLY1 to determine whether the relay RLY1 has switched its connection state. If the voltage signal is not received, it determines that the relay RLY1 has not switched its connection state, thereby determining that the relay RLY1 has malfunctioned, and then outputs a fault signal. After the fault detection module outputs a fault signal, the power supply output can be cut off according to the fault signal to avoid safety accidents, thereby improving the safety and stability of the smart socket.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it; under the concept of this utility model, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this utility model as described above, which are not provided in detail for the sake of brevity; although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A fault detection circuit, characterized in that, The fault detection circuit includes a control module, a relay RLY1, and a fault detection module. The control module is connected to the coil terminal of the relay RLY1, the common terminal of the relay RLY1 is connected to the power supply, the fault detection module is connected to the normally open terminal of the relay RLY1, and both the fault detection module and the control module are used to receive drive signals. The control module is used to control the coil terminal of the relay RLY1 to be energized when the drive signal is the first signal; The fault detection module is used to determine whether the voltage signal output by the power supply is received through the relay RLY1 when the drive signal is the first signal, and to output a fault signal when the voltage signal is not received.

2. The fault detection circuit according to claim 1, characterized in that, The fault detection circuit also includes a protection module; The protection module is connected to the fault detection module, and the protection module is also connected to the normally closed terminal of the relay RLY1 and the load respectively. The protection module is used to cut off the voltage signal output by the power supply through the relay RLY1 after receiving the fault signal.

3. The fault detection circuit according to claim 2, characterized in that, The fault detection module includes a detection unit and a comparison unit; The detection unit is connected to the normally open terminal of the relay RLY1 and the second input terminal of the comparison unit, respectively. The output terminal of the comparison unit is connected to the protection module. The first input terminal of the comparison unit is used to receive the drive signal. The detection unit is used to detect the output voltage of the normally open terminal of the relay RLY1 in real time, and input the output voltage to the second input terminal of the comparison unit; The comparison unit is used to determine whether the output voltage is less than the driving voltage corresponding to the first signal when the driving signal is the first signal, so as to determine whether the relay RLY1 is disconnected, and to output a fault signal when the output voltage is less than the driving voltage.

4. The fault detection circuit according to claim 3, characterized in that, The detection unit includes resistor R8, resistor R7, Zener diode D2, and capacitor C2; The resistor R8 is connected to the normally open terminal of the relay RLY1 and the anode of the Zener diode D2, respectively. The resistor R7 is connected in series with the resistor R8 and is also used for grounding. The cathode of the Zener diode D2 is connected to the capacitor C2 and the comparator unit, respectively. The capacitor C2 is also used for grounding.

5. The fault detection circuit according to claim 3, characterized in that, The comparison unit includes a comparator U1B and a pull-up resistor R9; The non-inverting input of the comparator U1B is used to receive the driving signal, the inverting input of the comparator U1B is connected to the detection unit, the output of the comparator U1B is connected to the first power supply through the pull-up resistor R9, and the output of the comparator U1B is used to connect to the protection module.

6. The fault detection circuit according to claim 1, characterized in that, The control module includes resistor R5, resistor R6, and switching transistor Q1; The control terminal of the switch Q1 receives the drive signal through the resistor R5. The control terminal of the switch Q1 is also connected to the second terminal of the switch Q1 through the resistor R6. The first terminal of the switch Q1 is connected to the coil terminal of the relay RLY1. The second terminal of the switch Q1 is used for grounding.

7. The fault detection circuit according to claim 2, characterized in that, The protection module includes a control unit and a relay RLY2; The control unit is connected to the fault detection module, and the control unit is also connected to the coil terminal of the relay RLY2. The connection terminal of the relay RLY2 is connected to the normally closed terminal of the relay RLY1 and the load, respectively. The control unit is used to energize the relay RLY2 after receiving the fault signal, thereby disconnecting the power supply from the load.

8. The fault detection circuit according to claim 7, characterized in that, The protection module also includes a light-emitting diode (LED1); The anode of the LED1 is connected to the fault detection module, and the cathode of the LED1 is connected to the control unit.

9. The fault detection circuit according to any one of claims 1-8, characterized in that, The fault detection circuit also includes a zero-crossing detection module; The zero-crossing detection module is connected to the control module and is also connected to the power supply. The zero-crossing detection module is also used to receive control signals. The zero-crossing detection module is used to detect the instantaneous voltage of the power supply, and when the instantaneous voltage is less than the first preset voltage, it outputs a corresponding drive signal to the control module according to the control signal, so that the relay RLY1 completes the switching action when the instantaneous voltage is less than the second preset voltage, wherein the second preset voltage is less than the first preset voltage.

10. A smart socket, characterized in that, The smart socket includes a fault detection circuit as described in any one of claims 1-9.

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