Load protection circuit, device and equipment
By designing a load protection circuit and utilizing the cooperation of a detection module and a power supply switch module, overvoltage detection and timely shutdown of equipment such as compressors are achieved, preventing equipment damage and ensuring safe operation of the equipment.
Patent Information
- Application Number
- CN202423155658.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2026-02-13
- Estimated Expiration
- 2034-12-20
AI Technical Summary
Existing compressor overpressure detection solutions may be unreliable under extreme operating conditions or the electronic components may be unresponsive, leading to compressor damage.
A load protection circuit was designed, including a detection module, a conduction control module, and a power supply switch module. The circuit detects abnormal operation of the load device by changing the state of an external switch and cuts off the power supply to prevent the load device from continuing to work under abnormal conditions.
This effectively prevents damage to the load equipment from continuing to operate under abnormal conditions, ensuring the safe operation of the equipment.
Smart Images
Figure CN223912237U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to the technical field of load protection, in particular to a load protection circuit, device and equipment. BACKGROUND
[0002] In the circuit system of the compressor control device, if the overvoltage operation of the compressor cannot be effectively detected and the compressor is not controlled to stop in time when the compressor is overvoltage operated, the working performance of the compressor may be affected and even the compressor may be damaged. The existing overvoltage detection mainly relies on a software scheme or a complex electronic circuit for detection. The former may be unreliable in extreme working conditions, and the latter may be not sensitive or even fail to react. Therefore, how to effectively detect the abnormal operation of the load device and protect it is a technical problem to be solved by those skilled in the art. CONTENT OF THE UTILITY MODEL
[0003] In order to solve the above technical problems or at least partially solve the above technical problems, the present disclosure provides a load protection circuit, device and equipment.
[0004] The present disclosure provides a load protection circuit, comprising a detection module, a conduction control module and a power supply switch module. The detection module is connected with an external switch, and is configured to output a first level signal according to the disconnection of the external switch; wherein the external switch is configured to be disconnected according to the fact that a to-be-detected physical quantity value of a load device does not conform to a preset physical quantity value range; the conduction control module is electrically connected with the detection module, and the conduction control module is configured to output a control signal according to the first level signal; and the power supply switch module is electrically connected with the conduction control module, and the power supply switch module is configured to cut off the power supply of a power supply module to the load device according to the control signal.
[0005] Optionally, the detection module comprises a first switch unit and a connector; a first end of the connector is connected with the power supply module, a first end of the external switch is connected with the first end of the connector, a second end of the external switch is connected with a second end of the connector, the second end of the connector is further connected with a first end of the first switch unit, a third end of the first switch unit is electrically connected with the power supply module, the third end of the first switch unit is further electrically connected with the conduction control module, a second end of the first switch unit and a fourth end of the first switch unit are both grounded; wherein the first switch unit is configured to disconnect the third end of the first switch unit and the fourth end of the first switch unit according to the disconnection of the external switch.
[0006] Optionally, the first switch unit comprises an optical coupler; a first input end of the optical coupler is electrically connected with the second end of the connector, a second input end of the optical coupler is electrically connected with the power supply module, the second input end of the optical coupler is further electrically connected with the conduction control module, a first output end of the optical coupler and a second output end of the optical coupler are both grounded.
[0007] Optionally, the conduction control module comprises a diode, a second switch unit and a third switch unit; a control end of the second switch unit is electrically connected with the detection module, a first end of the second switch unit is electrically connected with the power module, the first end of the second switch unit is also electrically connected with a control end of the third switch unit, a first end of the third switch unit is electrically connected with the power supply switch module, a second end of the second switch unit and a second end of the third switch unit are both grounded; a positive end of the diode is electrically connected with the first end of the third switch unit, and a negative end of the diode is electrically connected with the power module.
[0008] Optionally, the second switch unit comprises a first NMOS tube, and the third switch unit comprises a second NMOS tube; a gate of the first NMOS tube is electrically connected with the detection module, a source of the first NMOS tube is electrically connected with the power module, the source of the first NMOS tube is also electrically connected with a gate of the second NMOS tube, a source of the second NMOS tube is electrically connected with the power module, a drain of the first NMOS tube and a drain of the second NMOS tube are both grounded.
[0009] Optionally, the conduction control module further comprises a first filter capacitor, a second filter capacitor and a first filter resistor; a first end of the first filter capacitor is electrically connected with the gate of the first NMOS tube, a second end of the first filter capacitor is electrically connected with the drain of the first NMOS tube, a first end of the second filter capacitor and a first end of the first filter resistor are both electrically connected with the gate of the second NMOS tube, a second end of the second filter capacitor and a second end of the first filter resistor are both electrically connected with the drain of the second NMOS tube.
[0010] Optionally, the conduction control module further comprises a first current-limiting resistor and a second current-limiting resistor; the source of the first NMOS tube is electrically connected with the power module through the first current-limiting resistor, and the source of the first NMOS tube is also electrically connected with the gate of the second NMOS tube through the second current-limiting resistor.
[0011] Optionally, the conduction control module further comprises a diode, a positive end of the diode is electrically connected with the first end of the third switch unit, and a negative end of the diode is electrically connected with the second power supply unit.
[0012] Optionally, the power supply switch module comprises at least one relay; a control end of the relay is electrically connected with the conduction control module, a first end of the relay is electrically connected with the power module, and a second end of the relay is electrically connected with an input end of the load device.
[0013] The present disclosure also provides a load protection device comprising the load protection circuit as described above.
[0014] The present disclosure also provides a load protection device comprising the load protection device as described above.
[0015] The disclosure provides a load protection circuit, device and equipment, the load protection circuit comprises a detection module, a conduction control module and a power supply switch module. When the physical quantity value to be detected of the load device meets the preset physical quantity value range, the external switch remains in the conduction state, the detection module outputs a second level signal to the conduction control module, and the conduction control module controls the power supply switch module to keep the power module supplying power to the load device according to the second level signal. When the physical quantity value to be detected in the load device does not meet the preset physical quantity value range, the external switch is turned off. At this time, the detection module outputs a first level signal to the conduction control module according to the turning off of the external switch. The conduction control module outputs a control signal to the power supply switch module according to the received first level signal, and the power supply switch module cuts off the power supply of the power module to the load device according to the received control signal. Therefore, the disclosure determines that the load device is in an abnormal running condition according to the turning off of the external switch by the detection module, and outputs a first level signal to the conduction control module. The conduction control module outputs a control signal according to the first level signal, so that the power supply switch module cuts off the power supply of the power module to the load device, so that the load device stops working. Therefore, the damage of the load device caused by continuing to work in an abnormal state is avoided, and the working safety of the load device is effectively ensured. BRIEF DESCRIPTION OF DRAWINGS
[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creating any creative labor.
[0017] Figure 1 A structural schematic diagram of a load protection circuit provided by the embodiments of the present disclosure.
[0018] Figure 2 A structural schematic diagram of a preferred load protection circuit provided by the embodiments of the present disclosure. DETAILED DESCRIPTION
[0019] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In the following detailed description, many specific details are proposed in order to provide a comprehensive understanding of the present application. However, it is obvious to those skilled in the art that the present application can be implemented without some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by showing examples of the present application.
[0020] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The embodiments will be described in detail below with reference to the drawings.
[0021] Figure 1 This is a schematic diagram of a load protection circuit provided in an embodiment of the present disclosure, as shown below. Figure 1 As shown, the load protection circuit includes: a detection module 100, a conduction control module 200, and a power supply switch module 300. The detection module 100 is connected to an external switch 410, and is used to output a first-level signal based on the disconnection of the external switch 410; wherein, the external switch 410 is used to disconnect if the measured physical quantity value of the load device 420 does not meet the preset physical quantity value range; the conduction control module 200 is electrically connected to the detection module 100, and is used to output a control signal based on the first-level signal; the power supply switch module 300 is electrically connected to the conduction control module 200, and is used to cut off the power supply from the power supply module 430 to the load device 420 based on the control signal.
[0022] Specifically, the detection module 100 is connected to the external switch 410, and the detection module 100 is electrically connected to the power supply switch module 300 through the conduction control module 200. The power supply module 430 is electrically connected to the load device 420 through the power supply switch module 300. The external switch 410 is a switching device installed on the load device 420 to detect the physical quantity to be measured on the load device 420. When the value of the physical quantity to be measured on the load device 420 does not meet the preset physical quantity value range, the external switch 410 is open; when the value of the physical quantity to be measured on the load device 420 meets the preset physical quantity value range, the external switch 410 is closed. Therefore, the detection module 100 can determine whether the load device 420 is experiencing an operational abnormality based on the conduction status of the external switch 410.
[0023] When the physical quantity value to be measured of the load device 420 meets the preset physical quantity value range, the external switch 410 remains in the on state, and the detection module 100 outputs a second level signal to the on-off control module 200 according to the on state of the external switch 410. The on-off control module 200 controls the power supply switch module 300 to be on according to the second level signal, so as to keep the power supply module 430 supplying power to the load device 420. When the physical quantity value to be measured in the load device 420 does not meet the preset physical quantity value range, the external switch 410 is turned off. At this time, the detection module 100 outputs a first level signal to the on-off control module 200 according to the off state of the external switch 410. The on-off control module 200 outputs a control signal to the power supply switch module 300 according to the received first level signal, and the power supply switch module 300 is turned off according to the received control signal, so as to cut off the power supply of the power supply module 430 to the load device 420. Thus, the present disclosure determines that the load device 420 has an abnormal operation according to the off state of the external switch 410 by the detection module 100, and outputs the first level signal to the on-off control module 200. The on-off control module 200 outputs the control signal according to the first level signal, so as to make the power supply switch module 300 cut off the power supply of the power supply module 430 to the load device 420, thereby stopping the load device 420 from working in the case of abnormal operation. Thus, the damage of the load device 420 caused by continuous working in the abnormal state is avoided, and the working safety of the load device 420 is ensured. The first level signal is a high level signal, and the second level signal is a low level signal.
[0024] For example, when the load device is a compressor and the physical quantity value to be measured is a pressure value, the external switch is an external pressure switch, and the detection module is an overpressure detection module. When the pressure value of the compressor is less than the preset pressure value, the external pressure switch remains in the on state, and the overpressure detection module outputs a second level signal to the on-off control module according to the on state of the external pressure switch. The on-off control module controls the power supply switch module to be on according to the second level signal, so as to keep the power supply module supplying power to the compressor. When the pressure value in the compressor is greater than the preset pressure value, the external pressure switch is turned off. At this time, the overpressure detection module outputs a first level signal to the on-off control module according to the off state of the external pressure switch. The on-off control module outputs a control signal to the power supply switch module according to the received first level signal, and the power supply switch module is turned off according to the received control signal, so as to cut off the power supply of the power supply module to the compressor. Thus, the present disclosure determines that the compressor has an overpressure operation fault according to the off state of the external pressure switch by the overpressure detection module, and outputs the first level signal to the on-off control module. The on-off control module outputs the control signal according to the first level signal, so as to make the power supply switch module cut off the power supply of the power supply module to the compressor, thereby stopping the compressor from working in the case of overpressure operation. Thus, the damage of the compressor caused by continuous working in the overpressure state is avoided, and the working safety of the compressor is ensured.
[0025] It should be noted that the load device can also be other devices other than the compressor, and the to-be-measured physical quantity value can also be, for example, temperature, at which time the external switch can be an external temperature switch, and the detection module can be an over-temperature detection module; the to-be-measured physical quantity value can also be, for example, current, at which time the external switch can be an external current switch, and the detection module can be an over-current detection module. The specific to-be-measured physical quantity value can be set according to actual conditions, and is not specifically limited here.
[0026] In some embodiments, the detection module comprises: a first switch unit and a connector; a first end of the connector is connected with a first power supply end of the power supply module, the first end of the connector is connected with a first end of the external switch, a second end of the connector is connected with a second end of the external switch, the second end of the connector is also connected with a first end of the first switch unit, a third end of the first switch unit is electrically connected with a second power supply end of the power supply module, the third end of the first switch unit is also electrically connected with the conduction control module, a second end of the first switch unit and a fourth end of the first switch unit are both grounded; wherein the first switch unit is used to disconnect the third end of the first switch unit and the fourth end of the first switch unit according to the disconnection of the external switch.
[0027] Specifically, the external switch is connected to the detection module through the connector. When the external switch is turned on, the first power supply end of the power supply module connected to the first end of the connector and the first switch unit connected to the second end of the connector are turned on through the turned-on external switch, thereby realizing power supply to the first end of the first switch unit through the power supply module, turning on the third end of the first switch unit and the fourth end of the first switch unit, and the conduction control module receiving a low-level signal through the third end of the first switch unit and the fourth end of the first switch unit grounded by the turned-on first switch unit.
[0028] When the physical quantity value to be measured of the load device meets the preset physical quantity value range, the external switch remains in the on state, at this time, the two ends of the connector are conducted through the on external switch, so the first power supply end of the power module connected to the first end of the connector is conducted with the first switch unit connected to the second end of the connector, the first switch unit conducts the third end of the first switch unit and the fourth end of the first switch unit according to the voltage provided by the first power supply end of the power module, thereby grounding the on control module, that is, the on control module receives a low-level signal, and the on control module controls the power supply switch module to be on according to the low-level signal, so as to maintain the power supply of the power module to the load device. When the physical quantity value to be measured in the load device does not meet the preset physical quantity value range, the external switch is turned off, at this time, the two ends of the connector are not conducted, so the third end of the first switch unit and the fourth end of the first switch unit are not conducted, at this time, the second power supply end of the power module is electrically connected with the on control module, and the power module outputs a high-level signal to the on control module through the second power supply end. The on control module outputs a control signal to the power supply switch module according to the received high-level signal, and the power supply switch module is turned off according to the received control signal, so as to cut off the power supply of the power module to the load device. Thus, according to the abnormal operation of the load device, the two ends of the connector are disconnected through the external switch, and then the third end of the first switch unit and the fourth end of the first switch unit are disconnected, so that the on control module receives a high-level signal, and the on control module outputs a control signal according to the high-level signal, so as to make the power supply switch module cut off the power supply of the power module to the load device, so as to stop the load device from working in the case of abnormal operation, thereby avoiding the load device from being damaged due to continuous work in the abnormal state, and ensuring the safety of the load device.
[0029] In some embodiments, the first switch unit includes an optical coupler; the first input end of the optical coupler is electrically connected with the second end of the connector, the second input end of the optical coupler is electrically connected with the first power supply end of the power module, and the second input end of the optical coupler is also electrically connected with the on control module; the first output end of the optical coupler and the second output end of the optical coupler are both grounded.
[0030] Specifically, when the external switch is on, the first power supply end of the power module connected to the first end of the connector is conducted with the first input end of the optical coupler connected to the second end of the connector through the on external switch, at this time, the light-emitting diode in the optical coupler is on and emits light, and the photosensitive semiconductor in the optical coupler is also on after the light-emitting diode is lighted, thereby making the second input end of the optical coupler and the second output end of the optical coupler on, and the on control module is grounded through the on second input end of the optical coupler and the second output end of the optical coupler, thereby making the on control module receive a low-level signal.
[0031] When the physical quantity value to be measured of the load device meets the preset physical quantity value range, the external switch remains in the on state, at this time, the two ends of the connector are conducted through the on external switch, therefore, the first power supply end of the power module connected to the first end of the connector is conducted with the first input end of the optocoupler connected to the second end of the connector, the optocoupler lights up the light emitting diode in the optocoupler according to the voltage provided by the first power supply end of the power module, and the photosensitive semiconductor in the optocoupler is also conducted after sensing that the light emitting diode is lighted up, thereby grounding the on-off control module through the conducted photosensitive semiconductor, that is, the on-off control module receives a low-level signal, and the on-off control module controls the power supply switch module to be on according to the low-level signal, so as to maintain the power supply of the load device by the power module.
[0032] When the physical quantity value to be measured in the load device does not meet the preset physical quantity value range, the external switch is turned off, and the two ends of the connector are not conducted, therefore, the second input end of the optocoupler and the second output end of the optocoupler are not conducted, at this time, the second power supply end of the power module is electrically connected with the on-off control module, and the power module outputs a high-level signal to the on-off control module through the second power supply end. The on-off control module outputs a control signal to the power supply switch module according to the received high-level signal, and the power supply switch module is turned off according to the received control signal, so as to cut off the power supply of the load device by the power module. Therefore, according to the abnormal operation of the load device, the two ends of the connector are disconnected by the external switch, and the optocoupler is also disconnected, and the on-off control module outputs a control signal according to the received high-level signal, so as to make the power supply switch module cut off the power supply of the load device by the power module, thereby stopping the load device from working in the case of abnormal operation, so as to avoid damage to the load device caused by continuing to work in the abnormal state, and to ensure the safety of the load device.
[0033] In some embodiments, the on-off control module comprises a diode, a second switch unit and a third switch unit; the control end of the second switch unit is electrically connected with the detection module, the first end of the second switch unit is electrically connected with the third power supply end of the power module, the first end of the second switch unit is also electrically connected with the control end of the third switch unit, the first end of the third switch unit is electrically connected with the power supply switch module, and the second end of the second switch unit and the second end of the third switch unit are both grounded; the anode end of the diode is electrically connected with the first end of the third switch unit, and the cathode end of the diode is electrically connected with the third power supply end of the power module.
[0034] Specifically, when the physical quantity value of the load device to be detected meets the preset physical quantity value range, the detection module outputs a second level signal to the control end of the second switch unit, the second switch unit is in an open state, the third power supply end of the power supply module is directly electrically connected with the control end of the third switch unit, the third switch unit is turned on, at this time, the power supply switch module is grounded through the turned-on third switch unit, the power supply switch module maintains the turned-on state according to the received ground signal, so as to maintain the power supply of the power supply module to the load device. When the physical quantity value of the load device to be detected does not meet the preset physical quantity value range, the detection module outputs a first level signal to the control end of the second switch unit, the second switch unit is turned on, the gate resistance of the third switch unit is bypassed to the second switch unit, at this time, the third switch unit is turned off, and due to the reverse blocking characteristic of the diode, the third power supply end of the power supply module cannot output voltage to the power supply switch module through the diode, the third switch unit outputs an open circuit signal to the power supply switch module, and the open circuit signal received by the power supply switch module is the control signal output by the turn-on control module. The power supply switch module disconnects the connection between the power supply module and the load device according to the received open circuit signal, so as to stop the power supply of the power supply module to the load device, so that the load device stops working in the case of abnormal operation, thereby avoiding damage of the load device caused by continuous working of the load device in the abnormal state, and ensuring the working safety of the load device.
[0035] In some embodiments, the second switch unit comprises a first NMOS tube, and the third switch unit comprises a second NMOS tube; the gate of the first NMOS tube is electrically connected with the detection module, the source of the first NMOS tube is electrically connected with the power supply module, the source of the first NMOS tube is also electrically connected with the gate of the second NMOS tube, the source of the second NMOS tube is electrically connected with the power supply module, and the drain of the first NMOS tube and the drain of the second NMOS tube are both grounded.
[0036] Specifically, when the physical quantity value of the load device to be detected meets the preset physical quantity value range, the detection module outputs a low-level signal to the gate of the first NMOS tube, the first NMOS tube is in an off state, the third power supply end of the power supply module is directly electrically connected with the gate of the second NMOS tube, the second NMOS tube is turned on, at this time, the power supply switch module is grounded through the turned-on second NMOS tube, the power supply switch module keeps the on state according to the received ground signal, so as to keep the power supply module supplying power to the load device. When the physical quantity value of the load device to be detected does not meet the preset physical quantity value range, the detection module outputs a high-level signal to the gate of the first NMOS tube, the first NMOS tube is turned on, the gate resistor of the second NMOS tube is bypassed to the first NMOS tube, at this time, the second NMOS tube is turned off, and due to the reverse blocking characteristic of the diode, the third power supply end of the power supply module cannot output voltage to the power supply switch module through the diode, at this time, the power supply switch module receives the open circuit signal, and the open circuit signal received by the power supply switch module is the control signal output by the on-off control module. The power supply switch module disconnects the connection between the power supply module and the load device according to the received open circuit signal, so as to stop the power supply module from supplying power to the load device, thereby stopping the load device from working in the case of abnormal operation, avoiding damage to the load device caused by the load device continuing to work in the abnormal state, and ensuring the working safety of the load device.
[0037] In some embodiments, the on-off control module further comprises a first filter capacitor, a second filter capacitor and a first filter resistor; a first end of the first filter capacitor is electrically connected with the gate of the first NMOS tube, a second end of the first filter capacitor is electrically connected with the drain of the first NMOS tube, a first end of the second filter capacitor and a first end of the first filter resistor are both electrically connected with the gate of the second NMOS tube, and a second end of the second filter capacitor and a second end of the first filter resistor are both electrically connected with the drain of the second NMOS tube.
[0038] Specifically, the gate of the first NMOS tube is electrically connected with the detection module, and the level signal output by the detection module is output to the gate of the first NMOS tube after being filtered by the first filter capacitor, so that the gate of the first NMOS tube receives a stable level signal, thereby avoiding the problem that the gate of the first NMOS tube is erroneously turned on or turned off due to unstable received level signal. The gate of the second NMOS tube receives a ground signal when the first NMOS tube is turned on, and receives a level signal provided by the third power supply end of the power supply module when the first NMOS tube is turned off, the ground signal and the level signal are both filtered by the second filter capacitor and the first filter resistor before being input to the gate of the second NMOS tube, so that the gate of the second NMOS tube receives a stable level signal, thereby avoiding the problem that the gate of the second NMOS tube is erroneously turned on or turned off due to unstable received level signal.
[0039] In some embodiments, the conduction control module further comprises a first current-limiting resistor and a second current-limiting resistor; the source of the first NMOS transistor is electrically connected to the power module through the first current-limiting resistor, and the source of the first NMOS transistor is also electrically connected to the gate of the second NMOS transistor through the second current-limiting resistor.
[0040] Specifically, when the first NMOS transistor is turned on, the third power supply end of the power module is connected to the ground through the first current-limiting resistor, thereby avoiding the case that the third power supply end of the power module is directly connected to the ground and the power module is damaged. When the first NMOS transistor is turned off, the third power supply end of the power module is electrically connected to the gate of the second NMOS transistor through the first current-limiting resistor and the second current-limiting resistor, thereby avoiding the case that the second NMOS transistor is directly broken down due to the direct connection between the third power supply end of the power module and the gate of the second NMOS transistor, and thus the protection of the conduction control module is realized.
[0041] In some embodiments, the power supply switch module comprises at least one relay; the control end of the relay is electrically connected to the conduction control module, the first end of the relay is electrically connected to the power module, and the second end of the relay is electrically connected to the input end of the load device.
[0042] The at least one relay comprises a first relay, a second relay and a third relay; the control end of the first relay, the control end of the second relay and the control end of the third relay are electrically connected to the conduction control module; the first end of the first relay is electrically connected to the fourth power supply end of the power module; the second end of the first relay is electrically connected to the first input end of the load device; the first end of the second relay is electrically connected to the fifth power supply end of the power module; the second end of the second relay is electrically connected to the second input end of the load device; the first end of the third relay is electrically connected to the sixth power supply end of the power module; and the second end of the third relay is electrically connected to the third input end of the load device. When the internal voltage of the load device exceeds the preset voltage value, the conduction control module outputs a control signal, and the first relay, the second relay and the third relay are turned off according to the control signal, thereby cutting off the power supply of the power module to the load device, so that the load device stops working in the case of abnormal operation, thereby avoiding damage to the load device due to the continuous operation of the load device in the abnormal state, and ensuring the working safety of the load device.
[0043] Figure 2 A preferred structure diagram of a load protection circuit is provided for the embodiments of the present disclosure, as shown in Figure 2 The load protection circuit comprises a detection module 100, a conduction control module 200 and a power supply switch module 300.
[0044] The detection module 100 comprises an optical coupler 110, a connector 120, a third current-limiting resistor R3, a fourth current-limiting resistor R4, a fifth current-limiting resistor R5, a second filter resistor R7, a third filter capacitor C3, a fourth filter capacitor C4, a fifth filter capacitor C5, and a sixth filter capacitor C6.
[0045] The conduction control module 200 comprises a first NMOS tube Q1, a second NMOS tube Q2, a first current-limiting resistor R1, a second current-limiting resistor R2, a first filter resistor R6, a first filter capacitor C1, a second filter capacitor C2, a seventh filter capacitor C7, an eighth filter capacitor C8, a ninth filter capacitor C9, and a diode D1.
[0046] The power supply switch module 300 comprises a first relay 310, a second relay 320, and a third relay 330.
[0047] The first power supply end 431 of the power supply module 430 is electrically connected to the first end of the connector 120 through the third current-limiting resistor R3, the first end of the connector 120 is electrically connected to the first end of the external switch 410, the second end of the connector 120 is electrically connected to the second end of the external switch 410, the second end of the connector 120 is electrically connected to the first input end of the optical coupler 110, the first output end of the optical coupler 110 is grounded through the fourth current-limiting resistor R4, the first input end of the optical coupler 110 is electrically connected to the first end of the second filter resistor R7 and the first end of the third filter capacitor C3, the first output end of the optical coupler 110 is electrically connected to the second end of the second filter resistor R7 and the second end of the third filter capacitor C3, the second input end of the optical coupler 110 is electrically connected to the second power supply end 432 of the power supply module 430 through the fifth current-limiting resistor R5, the second power supply end 432 of the power supply module 430 is also grounded through the fourth filter capacitor C4, the second output end of the optical coupler 110 is grounded, the second input end of the optical coupler 110 is electrically connected to the first end of the fifth filter capacitor C5 and the first end of the sixth filter capacitor C6, the second output end of the optical coupler 110 is electrically connected to the second end of the fifth filter capacitor C5 and the second end of the sixth filter capacitor C6, and the second input end of the optical coupler 110 is electrically connected to the gate of the first NMOS tube Q1.
[0048] Specifically, the third current-limiting resistor R3 and the fourth current-limiting resistor R4 are used to limit the current output by the power module 430 to the first input end of the optical coupler 110, so as to avoid damage to the optical coupler 110 due to excessive input current. The second filter resistor R7 and the third filter capacitor C3 are used together to filter out abnormal signals mixed in the signal output by the power module 430 to the optical coupler 110. The fifth current-limiting resistor R5 is used to limit the current output by the power module 430 to the second input end of the optical coupler 110, so as to avoid damage to the optical coupler 110 due to excessive input current. The fifth filter capacitor C5 and the sixth filter capacitor C6 are used together to filter out abnormal signals mixed in the level signal output by the power module 430, so as to ensure the stability of the level signal output by the power module 430 to the gate of the first NMOS tube Q1.
[0049] The gate of the first NMOS tube Q1 is electrically connected to the first end of the first filter capacitor C1, the drain of the first NMOS tube Q1 is electrically connected to the second end of the first filter capacitor C1, the drain of the first NMOS tube Q1 is grounded, the source of the first NMOS tube Q1 is electrically connected to the third power supply end 433 of the power module 430 through the first current-limiting resistor R1, the source of the first NMOS tube Q1 is electrically connected to the gate of the second NMOS tube Q2 through the second current-limiting resistor R2, the drain of the second NMOS tube Q2 is grounded, the source of the second NMOS tube Q2 is electrically connected to the anode end of the diode D1, the anode and cathode ends of the diode D1 are electrically connected to the third power supply end 433 of the power module 430, the gate of the second NMOS tube Q2 is electrically connected to the first end of the first filter resistor R6 and the first end of the second filter capacitor C2, the drain of the second NMOS tube Q2 is electrically connected to the second end of the first filter resistor R6 and the second end of the second filter capacitor C2, and the third power supply end 433 of the power module 430 is grounded through the seventh filter capacitor C7, the eighth filter capacitor C8 and the ninth filter capacitor C9.
[0050] Specifically, the first filter capacitor C1 is used to make the gate of the first NMOS tube receive a stable level signal, so as to avoid the problem that the gate of the first NMOS tube is erroneously turned on or turned off due to unstable level signal received. The first filter resistor R6 and the second filter capacitor C2 are used together to make the gate of the second NMOS tube receive a stable level signal, so as to avoid the problem that the gate of the second NMOS tube is erroneously turned on or turned off due to unstable level signal received. The seventh filter capacitor C7, the eighth filter capacitor C8 and the ninth filter capacitor C9 are used together to stabilize the voltage output by the third power supply end 433 of the power module 430.
[0051] The control end of the first relay 310, the control end of the second relay 320 and the control end of the third relay 330 are electrically connected with the source of the second NMOS Q2, the first end of the first relay 310 is electrically connected with the fourth power supply end 434 of the power module 430, the second end of the first relay 310 is electrically connected with the first input end 421 of the load device 420, the first end of the second relay 320 is electrically connected with the fifth power supply end 435 of the power module 430, the second end of the second relay 320 is electrically connected with the second input end 422 of the load device 420, the first end of the third relay 330 is electrically connected with the sixth power supply end 436 of the power module 430, and the second end of the third relay 330 is electrically connected with the third input end 423 of the load device 420.
[0052] Specifically, when the physical quantity value of the load device 420 meets the preset physical quantity value range, the external switch 410 is in the on state, at this time, the two ends of the connector 120 are connected through the on external switch, so that the first power supply end 431 of the power module 430 connected to the first end of the connector 120 is connected to the first input end of the optocoupler 110 connected to the second end of the connector 120, and the optocoupler 110 is turned on according to the voltage provided by the first power supply end 431 of the power module 430, and the light emitting diode in the optocoupler 110 is turned on, and the photosensitive semiconductor in the optocoupler 110 is also turned on after sensing the light emitting diode, so that the gate of the first NMOS Q1 is grounded through the conductive photosensitive semiconductor, that is, the gate of the first NMOS Q1 receives a low-level signal. The first NMOS Q1 is disconnected according to the received low-level signal, at this time, the gate of the second NMOS Q2 is electrically connected with the third power supply end 433 of the power module 430, the second NMOS Q2 is turned on, at this time, the control end of the first relay 310, the control end of the second relay 320 and the control end of the third relay 330 are grounded through the conductive second NMOS Q2, the first relay 310, the second relay 320 and the third relay 330 remain in the on state, so as to maintain the power supply of the power module 430 to the load device 420.
[0053] When the physical quantity to be measured in the load device 420 does not conform to the preset physical quantity range, the external switch 410 is disconnected, the two ends of the connector 120 are not conducted, and thus the second input end of the optocoupler 110 and the second output end of the optocoupler 110 are not conducted. At this time, the second power supply end 432 of the power supply module 430 is electrically connected with the gate of the first NMOS tube Q1, the power supply module 430 outputs a high-level signal to the gate of the first NMOS tube Q1 through the second power supply end 432, the first NMOS tube Q1 is turned on according to the high-level signal, the gate of the second NMOS tube Q2 is grounded, and the second NMOS tube Q2 remains in a disconnected state. Due to the reverse blocking characteristic of the diode D1, the control end of the first relay 310, the control end of the second relay 320, and the control end of the third relay 330 will not receive a signal from the power supply module 430. The control end of the first relay 310, the control end of the second relay 320, and the control end of the third relay 330 will receive a signal that the second NMOS tube Q2 is in a disconnected state as a control signal, and the first relay 310, the second relay 320, and the third relay 330 are disconnected. Thus, the power supply module 430 is cut off from supplying power to the load device 420, so that the load device 420 stops working in the case of abnormal operation, thereby avoiding damage to the load device 420 caused by continuous operation in an abnormal state, and ensuring the working safety of the load device 420.
[0054] The present disclosure provides a load protection device comprising the load protection circuit according to any of the above embodiments.
[0055] It can be understood that the load protection device provided by the embodiments of the present application can achieve the corresponding beneficial effects of the load protection circuit provided by the above embodiments, which will not be repeated here.
[0056] The present disclosure provides a load protection device comprising the load protection circuit according to any of the above embodiments.
[0057] It can be understood that the load protection device provided by the embodiments of the present application can achieve the corresponding beneficial effects of the load protection circuit provided by the above embodiments, which will not be repeated here.
[0058] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.
[0059] The above are merely specific embodiments of this disclosure, enabling those skilled in the art to understand or implement this disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to these embodiments, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A load protection circuit, characterized by, The application relates to a power supply control device and a method thereof. The device comprises a detection module connected with an external switch, which is used for outputting a first level signal according to the disconnection of the external switch; wherein the external switch is used for being disconnected according to the fact that a physical quantity value of a load device to be detected does not conform to a preset physical quantity value range; A conduction control module is electrically connected with the detection module, and the conduction control module is used for outputting a control signal according to the first level signal; A power supply switch module is electrically connected with the conduction control module, and the power supply switch module is used for cutting off the power supply of a power supply module to the load device according to the control signal.
2. The load protection circuit of claim 1, wherein, The detection module comprises a first switch unit and a connector; A first end of the connector is connected with the power supply module, a first end of the external switch is connected with the first end of the connector, a second end of the external switch is connected with a second end of the connector, the second end of the connector is also connected with a first end of the first switch unit, a third end of the first switch unit is electrically connected with the power supply module, the third end of the first switch unit is also electrically connected with the conduction control module, a second end of the first switch unit and a fourth end of the first switch unit are both grounded; The first switch unit is used for disconnecting the third end of the first switch unit and the fourth end of the first switch unit according to the disconnection of the external switch.
3. The load protection circuit of claim 2, wherein, The first switch unit comprises an optical coupler; A first input end of the optical coupler is electrically connected with the second end of the connector, a second input end of the optical coupler is electrically connected with the power supply module, the second input end of the optical coupler is also electrically connected with the conduction control module, a first output end of the optical coupler and a second output end of the optical coupler are both grounded.
4. The load protection circuit of claim 1, wherein, The conduction control module comprises a diode, a second switch unit and a third switch unit; A control end of the second switch unit is electrically connected with the detection module, a first end of the second switch unit is electrically connected with the power supply module, the first end of the second switch unit is also electrically connected with a control end of the third switch unit, a first end of the third switch unit is electrically connected with the power supply switch module, a second end of the second switch unit and a second end of the third switch unit are both grounded; a positive electrode end of the diode is electrically connected with the first end of the third switch unit, and a negative electrode end of the diode is electrically connected with the power supply module.
5. The load protection circuit of claim 4, wherein, The second switch unit comprises a first NMOS tube, and the third switch unit comprises a second NMOS tube; A gate of the first NMOS tube is electrically connected with the detection module, a source of the first NMOS tube is electrically connected with the power supply module, the source of the first NMOS tube is also electrically connected with a gate of the second NMOS tube, a source of the second NMOS tube is electrically connected with the power supply module, a drain of the first NMOS tube and a drain of the second NMOS tube are both grounded.
6. The load protection circuit of claim 5, wherein, The conduction control module further comprises a first filter capacitor, a second filter capacitor and a first filter resistor. A first end of the first filter capacitor is electrically connected with a gate of the first NMOS tube, a second end of the first filter capacitor is electrically connected with a drain of the first NMOS tube, a first end of the second filter capacitor and a first end of the first filter resistor are electrically connected with a gate of the second NMOS tube, and a second end of the second filter capacitor and a second end of the first filter resistor are electrically connected with a drain of the second NMOS tube.
7. The load protection circuit of claim 5, wherein, The turn-on control module further comprises a first current-limiting resistor and a second current-limiting resistor; a source of the first NMOS tube is electrically connected with the power supply module through the first current-limiting resistor, and the source of the first NMOS tube is further electrically connected with a gate of the second NMOS tube through the second current-limiting resistor.
8. The load protection circuit of claim 1, wherein, The power supply switch module comprises at least one relay; a control end of the relay is electrically connected with the turn-on control module, a first end of the relay is electrically connected with the power supply module, and a second end of the relay is electrically connected with an input end of the load device.
9. A load protection device, characterized by The load protection circuit comprises any one of the load protection circuits according to claims 1-8.
10. A load protection device, characterized by, The load protection device comprises the load protection device according to claim 9.