Protection circuit and method, relay and electric equipment

Abstract

The invention discloses a protection circuit and method, a relay and electric equipment, and the protection circuit comprises a first switching tube, the input end and the control end of which are connected with the output end of a drive signal of the relay; the input end of the second switch tube is connected with the output end of the first switch tube, the output end of the second switch tube is connected with the first end of a coil of the relay, and the second end of the coil is grounded; the first input end of the over-temperature protection module inputs first voltage, the second input end of the over-temperature protection module inputs second voltage, and the output end of the over-temperature protection module is connected with the control end of the second switching tube; and the first input end of the over-current protection module inputs third voltage, the second input end of the over-current protection module is connected with a main loop where the first static contact and the second static contact of the relay are located, and the output end of the over-current protection module is connected with the control end of the second switching tube. According to the invention, the relay can be controlled to be switched off in time when an overcurrent condition occurs, so that the safety is improved and the maintenance cost is reduced at the same time.

Description

Technical Field

[0001] This invention relates to the field of electronic power technology, and more specifically, to a protection circuit, method, relay, and electrical equipment. Background Technology

[0002] Conventional normally open relays are simple structures consisting of a coil, armature, iron core, and contacts. They are commonly used in high-voltage circuits to prevent direct contact with high voltage. Because relays are used in high-voltage circuits, they are susceptible to strong overcurrents due to variations in input current, input voltage, or load, which can damage the relay and the main circuit. To address this, existing relays typically have single overcurrent or overtemperature protection. However, if this protection circuit fails, the relay will lose its protective function, leading to burnout, reduced safety, and increased maintenance costs.

[0003] There is currently no effective solution to the problem that existing relays use only overcurrent or overtemperature protection, which will lose their protective function and cause the relay to burn out if the protection circuit fails, thus reducing safety and increasing maintenance costs. Summary of the Invention

[0004] This invention provides a protection circuit, method, relay, and electrical equipment to solve the problem that in the prior art, relays use a single overcurrent protection or overtemperature protection method. Once the protection circuit fails, the relay will lose its protective function, resulting in the relay burning out, reducing safety, and increasing maintenance costs.

[0005] To solve the above-mentioned technical problems, the present invention provides a protection circuit applied to a relay, the relay including a coil, a first stationary contact, a second stationary contact, a first moving contact, a second moving contact, a third stationary contact, and a fourth stationary contact, the protection circuit including:

[0006] The first switching transistor has its input and control terminals connected to the output terminal of the drive signal of the relay;

[0007] The second switching transistor has its input terminal connected to the output terminal of the first switching transistor, its output terminal connected to the first terminal of the relay coil, and the second terminal of the coil grounded.

[0008] The over-temperature protection module has a first input terminal that receives a first voltage, a second input terminal that receives a second voltage, and an output terminal that is connected to the control terminal of the second switching transistor.

[0009] The overcurrent protection module has a third voltage input at its first input terminal, a second input terminal connected to the main circuit where the first and second stationary contacts of the relay are located, and an output terminal connected to the control terminal of the second switching transistor.

[0010] Furthermore, the over-temperature protection module includes:

[0011] A thermistor, whose first terminal is input with a first voltage;

[0012] The first voltage divider resistor has its first end connected to the second end of the thermistor, and its second end is grounded.

[0013] A second voltage divider resistor and a third voltage divider resistor are connected in series, with the second voltage divider resistor receiving a second voltage and the third voltage divider resistor being grounded;

[0014] The first comparator has its non-inverting input connected between the second and third voltage divider resistors, its inverting input connected between the thermistor and the first voltage divider resistor, and its output connected to the control terminal of the second switching transistor.

[0015] Furthermore, the overcurrent protection module includes:

[0016] A current sensor is disposed on the line between the first stationary contact of the relay and the input terminal of the main circuit, or on the line between the second stationary contact and the output terminal of the main circuit.

[0017] A fourth voltage divider resistor and a fifth voltage divider resistor are connected in series. The fourth voltage divider resistor is input with a third voltage, and the fifth voltage divider resistor is grounded.

[0018] The second comparator has its inverting input connected to the output of the current sensor, its non-inverting input connected between the fourth and fifth voltage divider resistors, and its output connected to the control terminal of the second switching transistor.

[0019] Furthermore, the protection circuit also includes:

[0020] The main control unit has a first input terminal connected to the output terminal of the over-temperature protection module, a second input terminal connected to the output terminal of the over-current protection module, and an output terminal connected to the control terminal of the first switching transistor. The main control unit is used to control whether to output the drive signal based on the signals output by the over-temperature protection module and / or the over-current protection module.

[0021] Furthermore, the protection circuit also includes:

[0022] A fault indicator light has its first end connected between the second end of the coil and ground, and its second end connected to the third stationary contact; the fault indicator light is used to illuminate when the coil is energized but the relay is open.

[0023] Furthermore, the protection circuit also includes:

[0024] The voltage conversion module has its input terminal connected to the output terminal of the drive signal, and its output terminal outputs the first voltage, the second voltage, and the third voltage, respectively.

[0025] The present invention also provides a protection method applied to the above-mentioned protection circuit, the protection method comprising:

[0026] Obtain the signals output by the over-temperature protection module and / or the over-current protection module;

[0027] The output of the drive signal is controlled based on the signals output by the over-temperature protection module and / or the over-current protection module.

[0028] Further, based on the signals output by the over-temperature protection module and / or the over-current protection module, controlling whether to output the drive signal includes:

[0029] If both the over-temperature protection module and the over-current protection module output high-level signals, then the drive signal is output.

[0030] If the over-temperature protection module and / or the over-current protection module outputs a low-level signal, then the drive signal will no longer be output.

[0031] The present invention also provides a relay including the above-described protection circuit.

[0032] The present invention also provides an electrical device including the aforementioned relay.

[0033] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the above-described protection method.

[0034] The present invention also provides an electronic device, comprising:

[0035] One or more processors;

[0036] A storage device for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement the protection method described above.

[0037] By applying the technical solution of this invention, both an over-temperature protection module and an over-current protection module are set up. The over-temperature protection module and the over-current protection module control the on / off state of the switching transistor, thereby controlling whether the relay coil is energized, thus switching the contact conduction state of the relay, and finally controlling the on / off state of the main circuit. Since overcurrent is often accompanied by overtemperature, by setting up over-temperature protection modules and over-current protection modules, dual protection is provided. In this way, even if one of the over-temperature protection module and the over-current protection module fails, the relay can still be disconnected smoothly, thereby ensuring that the relay disconnects in time when an overcurrent occurs, avoiding damage to the relay, improving safety and reducing maintenance costs. Attached Figure Description

[0038] Figure 1 This is a structural diagram of the protection circuit according to an embodiment of the present invention;

[0039] Figure 2 A flowchart of a protection method according to an embodiment of the present invention;

[0040] Figure 3 This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0042] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0043] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0044] It should be understood that although the terms first, second, third, etc., may be used to describe voltage divider resistors in the embodiments of the present invention, these voltage divider resistors should not be limited to these terms. These terms are only used to distinguish different voltage divider resistors. For example, without departing from the scope of the embodiments of the present invention, a first voltage divider resistor may also be referred to as a second voltage divider resistor, and similarly, a second voltage divider resistor may also be referred to as a first voltage divider resistor.

[0045] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0046] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0047] The optional embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0048] Example 1

[0049] Conventional normally open relays are simple structures consisting of a coil, armature, iron core, and contacts. They are commonly used in high-voltage circuits to prevent direct contact with high voltage. Because relays are used in high-voltage circuits, they are susceptible to unexpected situations such as strong overcurrent due to input or load variations, leading to relay burnout. To address this, existing relays typically have single overcurrent or overtemperature protection. However, if this protection circuit fails, the relay loses its protective function, resulting in burnout, reduced safety, and increased maintenance costs.

[0050] To address the problem that existing relays employ only single overcurrent or overtemperature protection methods, which can lead to relay burnout, reduced safety, and increased maintenance costs if the protection circuit fails, this embodiment provides a protection circuit for relays. Figure 1 This is a structural diagram of the protection circuit according to an embodiment of the present invention, such as... Figure 1As shown, the relay includes a coil L1, a first stationary contact 1, a second stationary contact 2, a first moving contact 3, a second moving contact 4, a third stationary contact 5, and a fourth stationary contact 6. The first moving contact 3 and the second moving contact 4 are connected by an armature, which is connected to a spring T1. When the coil L1 is not energized, the first moving contact 3 is connected to the third stationary contact 5, and the second moving contact 4 is connected to the fourth stationary contact 6. When the coil L1 is energized, the first moving contact 3 is connected to the first stationary contact 1, and the second moving contact 4 is connected to the second stationary contact 2.

[0051] like Figure 1 As shown, the protection circuit includes: a first switching transistor Q1, whose input and control terminals are connected to the output terminal of the relay's drive signal, used to input a drive signal with a certain voltage value (e.g., 12V) to drive the relay; a second switching transistor Q2, whose input terminal is connected to the output terminal of the first switching transistor Q1, whose output terminal is connected to the first terminal of the relay's coil L1, and the second terminal of the coil L1 is grounded; an over-temperature protection module 7, whose first input terminal receives a first voltage V1, whose second input terminal receives a second voltage V2, and whose output terminal is connected to the control terminal of the second switching transistor Q2; and an over-current protection module 8, whose first input terminal receives a third voltage V3, whose second input terminal is connected to the main circuit where the first stationary contact 1 and the second stationary contact 2 of the relay are located, and whose output terminal is connected to the control terminal of the second switching transistor Q2.

[0052] When the relay is not energized, it is normally open, with contacts 3 and 5 closed, and contacts 4 and 6 closed. The main circuit is open, and there is no 12V drive signal input. The first switch Q1 and the second switch Q2 are disconnected. When the relay is energized, a 12V drive signal is input, driving the first switch Q1. The first switch Q1 closes, and both the over-temperature protection module 7 and the over-current protection module 8 output a high level. The second switch Q2 closes, energizing coil L1 and generating a magnetic force to attract the armature. At this time, contacts 3 and 1 close, contacts 4 and 2 close, the main circuit is connected, and contacts 5 and 6 are not connected.

[0053] The protection circuit of this embodiment includes both an over-temperature protection module 7 and an over-current protection module 8. These modules control the switching of the switching transistor, thereby controlling whether the relay coil L1 is energized, thus switching the relay contact conduction state and ultimately controlling the main circuit's on / off state. Since overcurrent is often accompanied by overtemperature, the inclusion of both modules provides dual protection. Even if one of these modules fails, the relay can still disconnect smoothly, ensuring timely disconnection in the event of an overcurrent and preventing damage to the relay. This improves safety and reduces maintenance costs.

[0054] Overcurrent is often accompanied by overtemperature. To ensure that the control relay disconnects in the event of overtemperature in the main circuit, such as... Figure 1 As shown, the above-mentioned over-temperature protection module 7 includes: a thermistor Rx, whose first terminal is input to a first voltage V1; a first voltage divider resistor R1, whose first terminal is connected to the second terminal of the thermistor Rx, and whose second terminal is grounded, and the first voltage divider resistor R1 is set near the main circuit line or heating element; a second voltage divider resistor R2 and a third voltage divider resistor R3 set in series, the second voltage divider resistor R2 is input to a second voltage V2, and the third voltage divider resistor R3 is grounded; a first comparator U1, whose non-inverting input terminal is connected between the second voltage divider resistor R2 and the third voltage divider resistor R3, whose inverting input terminal is connected between the thermistor Rx and the first voltage divider resistor R1, and whose output terminal is connected to the control terminal of the second switching transistor Q2.

[0055] When the main circuit is normally conducting and no overcurrent occurs, the temperature and resistance of the thermistor Rx are low, and the voltage at the inverting input of the first comparator U1 is low, lower than the voltage at the non-inverting input. Therefore, the first comparator U1 outputs a high level, controlling the second switch Q2 to conduct, which in turn controls the relay coil L1 to be energized, the armature to be attracted, contacts 3 and 1 to close, and contacts 4 and 2 to close, thus conducting the main circuit. After an overcurrent occurs, because overcurrent is often accompanied by the device circuit getting hot, the temperature of the thermistor Rx is high, and the resistance increases. The voltage at the inverting input of the first comparator U1 increases, higher than the voltage at the non-inverting input. Therefore, the first comparator U1 outputs a low level, controlling the second switch Q2 to be de-energized, which in turn controls the relay coil L1 to be de-energized. Spring T1 pulls the armature back, contacts 3 and 5 to close, and contacts 4 and 6 to close, thus disconnecting the main circuit and ensuring safety.

[0056] To ensure the relay disconnects in the event of an overcurrent in the main circuit, the overcurrent protection module 8 includes: a current sensor U3, disposed on the line between the first stationary contact 1 of the relay and the input terminal of the main circuit, or on the line between the second stationary contact 2 and the output terminal of the main circuit. In this embodiment, the current sensor U3 is disposed on the line between the second stationary contact 2 and the output terminal of the main circuit. A fourth voltage divider resistor R4 and a fifth voltage divider resistor R5 are connected in series, with the fourth voltage divider resistor R4 receiving a third voltage V3 and the fifth voltage divider resistor R5 grounded; a second comparator U2, whose inverting input is connected to the output terminal of the current sensor U3, whose non-inverting input is connected between the fourth voltage divider resistor R4 and the fifth voltage divider resistor R5, and whose output is connected to the control terminal of the second switching transistor Q2.

[0057] When the main circuit is normally conducting and no overcurrent occurs, the current sensor U3 samples the voltage, and the output sampled voltage is input to the inverting input of the second comparator U2. Due to the small current, the sampled voltage is low, and the voltage at the inverting input of the second comparator U2 is less than the voltage at its non-inverting input. The second comparator U2 outputs a high level, controlling the second switch Q2 to conduct, which in turn controls the relay coil L1 to be energized, the armature to be attracted, contacts 3 and 1 to close, and contacts 4 and 2 to close, thus conducting the main circuit. When an overcurrent occurs in the main circuit, the current sensor U3 samples the voltage, and the output sampled voltage is input to the inverting input of the second comparator U2. Due to the large current, the sampled voltage is large, and the voltage at the inverting input of the second comparator U2 is less than the voltage at its non-inverting input. The second comparator U2 outputs a low level, controlling the second switch Q2 to be turned off, which in turn controls the relay coil L1 to be de-energized. Spring T1 pulls the armature back, contacts 3 and 5 to close, and contacts 4 and 6 to close, thus disconnecting the main circuit and ensuring safety.

[0058] In the event of an overcurrent, the output signal from either the over-temperature protection module 7 or the over-current protection module 8 can control the second switch Q2 to turn off. However, if the second switch Q2 fails, both the over-temperature protection module 7 and the over-current protection module 8 will also fail simultaneously, making it impossible to guarantee that the relay will disconnect. To avoid this situation, an additional layer of protection is implemented, such as... Figure 1 As shown, the protection circuit further includes a main control unit (MCU), whose first input terminal is connected to the output terminal of the over-temperature protection module 7, its second input terminal is connected to the output terminal of the over-current protection module 8, and its output terminal is connected to the control terminal of the first switching transistor Q1. The main control unit (MCU) is used to control whether to output a relay drive signal based on the signals output by the over-temperature protection module and / or the over-current protection module. If the signals output by the over-temperature protection module 7 and the over-current protection module 8 are both high-level signals, a drive signal is output to control the first switching transistor to turn on; if the signals output by the over-temperature protection module and / or the over-current protection module are low-level signals, no drive signal is output, thereby causing the first switching transistor Q1 to turn off. In this way, even if the second switching transistor Q2 fails, the relay can still be disconnected in time under overcurrent conditions, achieving triple protection.

[0059] In some cases, although the relay coil is energized, a relay malfunction may prevent the armature from engaging, thus preventing the main circuit from conducting. To allow users to visually observe the relay's fault status, the aforementioned protection circuit further includes a fault indicator light D1, whose first terminal is connected between the second terminal of coil L1 and ground, and whose second terminal is connected to the third stationary contact 3. In this embodiment, a sixth voltage-dividing resistor R6 and a seventh voltage-dividing resistor R7 are connected in series between the second terminal of coil L1 and ground, and the first terminal of fault indicator light D1 is connected between the sixth voltage-dividing resistor R6 and the seventh voltage-dividing resistor R7. The fault indicator light D1 illuminates when coil T1 is energized but the relay is open.

[0060] When the relay is not energized, there is no 12V drive signal input, the relay is in the normally open state, contacts 3 and 5 are closed, contacts 4 and 6 are closed, the main circuit is disconnected, there is no 12V drive signal input, the first switch Q1 and the second switch Q2 are disconnected, and the fault indicator D1 is not lit. When the relay is energized and the relay is normally closed, there is a 12V drive signal input, the first switch Q1 is driven by the input signal and closes, the over-temperature protection module 7 and the over-current protection module 8 both output a high level, the second switch Q2 closes, so that the coil L1 is energized, generating a magnetic force to attract the armature, at this time the contact... When contacts 3 and 1 are closed, and contacts 4 and 2 are closed, the main circuit is connected. Contacts 5 and 6 are not connected, and the fault indicator D1 is off. When the relay is energized but cannot close normally, a 12V drive signal is input, and the first switch Q1 is driven by the input signal. The first switch Q1 closes, and both the over-temperature protection module 7 and the over-current protection module 8 output a high level. The second switch Q2 closes, energizing the coil L1. Due to the relay fault, the armature does not move. At this time, contacts 3 and 5 are closed, and contacts 4 and 6 remain closed, so the main circuit is not connected. Contacts 5 and 6 are connected, and the fault indicator D1 lights up.

[0061] The above text mentions that the first terminal of the thermistor Rx receives a first voltage V1, the second voltage divider resistor R2 receives a second voltage V2, and the fourth voltage divider resistor R4 receives a third voltage V3. To avoid introducing a new voltage source and save on component costs, the relay's drive voltage source could be used to output the aforementioned first voltage V1, second voltage V2, and third voltage V3. However, the aforementioned first voltage V1, second voltage V2, and third voltage V3 are all less than the relay's drive voltage. Therefore, if... Figure 1 As shown, the protection circuit also includes a voltage conversion module 9, whose input terminal is connected to the output terminal of the relay drive signal, and whose output terminal outputs a first voltage V1, a second voltage V2 and a third voltage V3 respectively.

[0062] Example 2

[0063] This embodiment provides another protection circuit, as mentioned above. Figure 1 As shown in the figure, this embodiment includes eight parts: a first switching transistor Q1, a second switching transistor Q2 (both Q1 and Q2 are N-type transistors); a relay control coil L1; a self-testing circuit consisting of a fault indicator D1, a sixth voltage divider resistor R6, and a seventh voltage divider resistor R7; a voltage conversion module 9 for converting 12V to 3.3V; an over-temperature protection module 7 consisting of a first comparator U1, a first voltage divider resistor R1, a second voltage divider resistor R2, and a third voltage divider resistor R3; an over-current protection module consisting of a current sensor U3, a fourth voltage divider resistor R4, a third voltage divider resistor R5, and a second comparator U2; contacts 1 to 6; and a spring T1.

[0064] Work status:

[0065] 1. When the relay is not powered, there is no 12V drive signal input, the relay is in the normally open state, contacts 3 and 4 are connected through the armature, contacts 3 and 5 are closed, contacts 4 and 6 are closed, the main circuit is disconnected, the first switch Q1 and the second switch Q2 are disconnected, and the fault indicator D1 does not light up.

[0066] 2. When the relay is energized, a 12V drive signal is input, and the first switch Q1 is driven by the input signal. The first switch Q1 closes, and both the first comparator U1 and the second comparator U2 output a high level. The second switch Q2 closes, and the coil L1 is energized, generating a magnetic force to attract the armature. At this time, contacts 3 and 1 close, contacts 4 and 2 close, and the main circuit is connected. At this time, contacts 5 and 6 are not connected, and the fault indicator D1 does not light up.

[0067] Over-temperature and over-current protection:

[0068] 1. When the load is short-circuited or abnormal, the circuit may generate a large current, which may cause the main circuit to heat up rapidly and burn out the components. When the main circuit is normally conducting and no overcurrent occurs, the current sensor U3 samples the voltage, and the output sampled voltage is input to the inverting input of the second comparator U2. Due to the small current, the sampled voltage is low, and the voltage at the inverting input of the second comparator U2 is less than the voltage at its non-inverting input. The second comparator U2 outputs a high level, controlling the second switch Q2 to conduct, which in turn controls the relay coil L1 to be energized, the armature to be attracted, contacts 3 and 1 to close, and contacts 4 and 2 to close, thus conducting the main circuit. When an overcurrent occurs in the main circuit, the current sensor U3 samples the voltage, and the output sampled voltage is input to the inverting input of the second comparator U2. Due to the large current, the sampled voltage is large, and the voltage at the inverting input of the second comparator U2 is less than the voltage at its non-inverting input. The second comparator U2 outputs a low level, controlling the second switch Q2 to be turned off, which in turn controls the relay coil L1 to be de-energized. Spring T1 pulls the armature back, contacts 3 and 5 to close, and contacts 4 and 6 to close, thus disconnecting the main circuit and ensuring safety.

[0069] 2. Since overcurrent is often accompanied by overheating of the device circuit, over-temperature protection is added for double protection. A thermistor Rx and the first voltage divider resistor R1 are set in the circuit. When the main circuit is normally conducting and no overcurrent occurs, the temperature and resistance of the thermistor Rx are low, and the voltage at the inverting input of the first comparator U1 is low, lower than the voltage at the non-inverting input. Therefore, the first comparator U1 outputs a high level, controlling the second switch Q2 to conduct, which in turn controls the relay coil L1 to be energized, the armature to be attracted, contacts 3 and 1 to close, and contacts 4 and 2 to close, thus conducting the main circuit. After an overcurrent occurs, because overcurrent is often accompanied by the device circuit getting hot, the temperature of the thermistor Rx is high, and the resistance increases. The voltage at the inverting input of the first comparator U1 increases, higher than the voltage at the non-inverting input. Therefore, the first comparator U1 outputs a low level, controlling the second switch Q2 to be de-energized, which in turn controls the relay coil L1 to be de-energized. Spring T1 pulls the armature back, contacts 3 and 5 to close, and contacts 4 and 6 to close, thus disconnecting the main circuit and ensuring safety.

[0070] 3. The output terminals of the overcurrent protection module 8 and the overtemperature protection module 7 are both connected to the main control unit MCU through device pins. When an overcurrent occurs, both the overcurrent protection module 8 and the overtemperature protection module 7 output a low level. After receiving the low level signals output by both the overcurrent protection module 8 and the overtemperature protection module 7, the main control unit MCU stops outputting the drive signal and then controls the first switching transistor Q1 to turn off, forming a soft and hard dual turn-off.

[0071] Self-check:

[0072] When the relay receives a drive signal input and is fault-free, a 12V drive signal input closes the first switch Q1, and the first comparator U1 and the second comparator U2 output a high level. The second switch Q2 closes, and the coil L1 is energized, generating a magnetic force to attract the armature. At this time, contacts 3 and 1 close, and contacts 4 and 2 close, and the main circuit is connected. At this time, contacts 5 and 6 are not connected, and the fault indicator D1 does not light up, indicating that the relay is not abnormal.

[0073] When the relay receives a drive signal input and the relay malfunctions, a 12V drive signal is input, the first switch Q1 closes, the first comparator U1 and the second comparator U2 output a high level, the second switch Q2 closes, and the L1 coil is energized. However, due to the relay malfunction, the armature does not operate. At this time, contacts 3 and 5, and contacts 4 and 6 remain closed. The fault indicator D1 forms a circuit and lights up, indicating that the relay is abnormal and should be replaced.

[0074] Example 3

[0075] This embodiment provides a protection method applied to the protection circuit of the above embodiment. Figure 2 A flowchart of a protection method according to an embodiment of the present invention is shown below. Figure 2 As shown, the above protection method includes:

[0076] S101, acquire the signals output by the over-temperature protection module and / or the over-current protection module.

[0077] S102 controls whether to output a drive signal based on the signals output by the over-temperature protection module and / or the over-current protection module.

[0078] As mentioned above, in the event of an overcurrent, the output signal of either the over-temperature protection module 7 or the overcurrent protection module 8 can control the second switch Q2 to turn off. However, if the second switch Q2 fails, both the over-temperature protection module 7 and the overcurrent protection module 8 will also fail to function simultaneously, and the relay cannot be guaranteed to disconnect. To avoid this situation and achieve an additional layer of protection, the protection circuit further includes a main control unit (MCU), whose first input terminal is connected to the output terminal of the over-temperature protection module 7, its second input terminal is connected to the output terminal of the overcurrent protection module 8, and its output terminal is connected to the control terminal of the first switch Q1. The main control unit (MCU) is used to control whether it outputs the drive signal based on the signals output by the over-temperature protection module and / or the overcurrent protection module.

[0079] The protection method in this embodiment obtains the signals output by the over-temperature protection module and / or over-current protection module through the main control unit MCU, and controls whether to output a drive signal based on the signals output by the over-temperature protection module and / or over-current protection module. This ensures that when the hardware protection scheme that controls the switching transistor to disconnect through the over-temperature protection module and over-current protection module fails, the output drive signal is stopped through software, thereby turning off the relay and ensuring safety.

[0080] Specifically, based on the signals output by the over-temperature protection module and / or the over-current protection module, control whether to output a drive signal, including: if the signals output by the over-temperature protection module and the over-current protection module are both high-level signals, then output a drive signal; if the signals output by the over-temperature protection module and / or the over-current protection module are low-level signals, then no drive signal is output.

[0081] If both the over-temperature protection module and the over-current protection module output high-level signals, it indicates that no overcurrent has occurred, and therefore the drive signal can be output normally to close the relay. If the over-temperature protection module and / or the over-current protection module output low-level signals, it indicates that an overcurrent has occurred. In this case, the drive signal will no longer be output, and the relay will be turned off by software to disconnect the main circuit and ensure safety.

[0082] Example 4

[0083] This embodiment provides a relay including the protection circuit described in the above embodiment, which is used to ensure that the relay disconnects in time when an overcurrent occurs, so as to avoid damage to the relay, thereby improving safety and reducing maintenance costs.

[0084] Example 5

[0085] This embodiment provides an electrical device, including the relay described in the above embodiment.

[0086] Example 6

[0087] This embodiment provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the protection method of the above embodiment.

[0088] Example 7

[0089] This embodiment provides an electronic device, including:

[0090] One or more processors;

[0091] A storage device for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement the protection method of the above embodiments.

[0092] Figure 3This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention, such as... Figure 3 As shown, the electronic device includes:

[0093] One or more processors 310 and memory 320, Figure 3 Take the 310 processor as an example.

[0094] The aforementioned electronic device may further include: an input device 330 and an output device 340.

[0095] The processor 310, memory 320, input device 330, and output device 340 can be connected via a bus or other means. Figure 3 Taking the example of a connection between China and Israel via a bus.

[0096] The memory 320, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to the anomaly detection method in this embodiment of the invention. The processor 310 executes various functional applications and data processing of the server by running the non-volatile software programs, instructions, and modules stored in the memory 320, thereby implementing the above-described method embodiments.

[0097] The memory 320 may include a program storage area and a data storage area, wherein the program storage area may store application programs required for operating the device and at least one function; and the data storage area may store data created based on the use of the anomaly detection device, etc. Furthermore, the memory 320 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

[0098] Input device 330 can receive input digital or character information, and generate key signal inputs related to user settings and function control of the electronic device. Output device 340 may include display devices such as a display screen.

[0099] The one or more modules are stored in the memory 320, and when executed by the one or more processors 310, they execute the anomaly detection method in any of the above method embodiments.

[0100] The aforementioned electronic device product can execute the method provided in the embodiments of the present invention, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in this embodiment can be found in the method provided in the embodiments of the present invention.

[0101] The electronic devices of this invention exist in various forms, including but not limited to:

[0102] (1) Mobile communication devices: These devices are characterized by their mobile communication capabilities and are primarily designed to provide voice and data communication. These terminals include smartphones (e.g., iPhones), multimedia phones, feature phones, and low-end phones.

[0103] (2) Ultra-mobile personal computer devices: These devices fall under the category of personal computers, have computing and processing functions, and generally also have mobile internet access capabilities. These terminals include: PDAs, MIDs, and UMPCs, such as iPads.

[0104] (3) Portable entertainment devices: These devices can display and play multimedia content. This category includes: audio and video players (such as iPods), handheld game consoles, e-books, as well as smart toys and portable car navigation devices.

[0105] (4) Server: A device that provides computing services. The components of a server include a processor, hard disk, memory, device bus, etc. Servers are similar to general computer architectures, but because they need to provide highly reliable services, they have higher requirements in terms of processing power, stability, reliability, security, scalability, and manageability.

[0106] (5) Other electronic devices with data interaction functions, such as televisions, in-vehicle screens, etc.

[0107] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0108] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the protection methods described in various embodiments or some parts of embodiments.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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 spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A protection circuit applied to a relay, the relay comprising a coil, a first stationary contact, a second stationary contact, a first moving contact, a second moving contact, a third stationary contact, and a fourth stationary contact, characterized in that, The protection circuit includes: The first switching transistor has its input and control terminals connected to the output terminal of the drive signal of the relay; The second switching transistor has its input terminal connected to the output terminal of the first switching transistor, its output terminal connected to the first terminal of the relay coil, and the second terminal of the coil grounded. The over-temperature protection module has a first input terminal that receives a first voltage, a second input terminal that receives a second voltage, and an output terminal that is connected to the control terminal of the second switching transistor. The overcurrent protection module has a first input terminal that receives a third voltage, a second input terminal that is connected to the main circuit where the first and second stationary contacts of the relay are located, and an output terminal that is connected to the control terminal of the second switching transistor.

2. The protection circuit according to claim 1, characterized in that, The over-temperature protection module includes: A thermistor, whose first terminal is input with a first voltage; The first voltage divider resistor has its first end connected to the second end of the thermistor, and its second end is grounded. A second voltage divider resistor and a third voltage divider resistor are connected in series, with the second voltage divider resistor receiving a second voltage and the third voltage divider resistor being grounded; The first comparator has its non-inverting input connected between the second and third voltage divider resistors, its inverting input connected between the thermistor and the first voltage divider resistor, and its output connected to the control terminal of the second switching transistor.

3. The protection circuit according to claim 1, characterized in that, The overcurrent protection module includes: A current sensor is disposed on the line between the first stationary contact of the relay and the input terminal of the main circuit, or on the line between the second stationary contact and the output terminal of the main circuit. A fourth voltage divider resistor and a fifth voltage divider resistor are connected in series. The fourth voltage divider resistor is input with a third voltage, and the fifth voltage divider resistor is grounded. The second comparator has its inverting input connected to the output of the current sensor, its non-inverting input connected between the fourth and fifth voltage divider resistors, and its output connected to the control terminal of the second switching transistor.

4. The protection circuit according to claim 1, characterized in that, The protection circuit also includes: The main control unit has a first input terminal connected to the output terminal of the over-temperature protection module, a second input terminal connected to the output terminal of the over-current protection module, and an output terminal connected to the control terminal of the first switching transistor. The main control unit is used to control whether to output the drive signal based on the signals output by the over-temperature protection module and / or the over-current protection module.

5. The protection circuit according to claim 1, characterized in that, The protection circuit also includes: A fault indicator light has its first end connected between the second end of the coil and ground, and its second end connected to the third stationary contact; the fault indicator light is used to illuminate when the coil is energized but the relay is open.

6. The protection circuit according to claim 1, characterized in that, The protection circuit also includes: The voltage conversion module has its input terminal connected to the output terminal of the drive signal, and its output terminal outputs the first voltage, the second voltage, and the third voltage, respectively.

7. A protection method, applied to the protection circuit according to any one of claims 1 to 6, characterized in that, The protection method includes: Obtain the signals output by the over-temperature protection module and / or the over-current protection module; The output of the drive signal is controlled based on the signals output by the over-temperature protection module and / or the over-current protection module.

8. The protection method according to claim 7, characterized in that, Based on the signals output by the over-temperature protection module and / or the over-current protection module, control whether to output the drive signal, including: If both the over-temperature protection module and the over-current protection module output high-level signals, then the drive signal is output. If the over-temperature protection module and / or the over-current protection module outputs a low-level signal, then the drive signal will no longer be output.

9. A relay, characterized in that, The protection circuit includes any one of claims 1 to 6.

10. An electrical appliance, characterized in that, Includes the relay as described in claim 9.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the protection method as described in claim 7 or 8.

12. An electronic device, characterized in that, include: One or more processors; A storage device for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement the protection method as described in claim 7 or 8.

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