Electric equipment protection device

Abstract

The invention discloses an electric equipment protection device, which is connected to electric equipment and a power supply end, and comprises a reference module for outputting a reference voltage according to the information of the electric equipment; the control module is connected to the reference module and the power supply end and outputs a control signal according to the reference voltage and the power supply end voltage; the detection module is connected to the control module and acts based on the control signal of the control module to output a load detection signal; and the switch module is connected to the electric equipment and the control module and acts based on the control signal of the control module to control the working state of the electric equipment. The method has the advantages that when the voltage of the power supply end does not meet the reference voltage, the loop between the electric equipment and the power supply end is disconnected, the situation that the electric equipment is started when the voltage cannot meet the reference voltage is avoided, and normal operation of user equipment is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of circuit protection, and in particular to a protection device for electrical equipment. Background Art

[0002] In a DC power supply system, the load power is often greater than the power supply power. For example, the power consumption equipment requires 5V / 2A, while the power supply equipment outputs 5V / 1A. If the power consumption equipment is a lamp (commonly used in desk lamps with USB interfaces), the light will flicker all the time and cannot work normally. If the power consumption equipment is a motor product (commonly used in electric staplers, electric desks, electric curtains, etc.), since double the current is required at the moment of startup, if the power is turned on without judging whether the power supply is sufficient, the motor may be damaged.

[0003] like Figure 1 As shown, in the related art, no matter how many volts the output voltage and current are, they will directly pass through the electrical equipment Rload. When the power supply is insufficient, it is easy to cause abnormality in the electrical equipment.

[0004] The Chinese patent "A low-voltage protection circuit for LED lamps", publication number: CN214101865U, publication date: August 31, 2021, specifically discloses a rectifier circuit connected to the mains, a drive circuit connected to the LED load, and a voltage detection control circuit. The rectifier circuit and the drive circuit are connected, the input end of the voltage detection control circuit is connected to the bus voltage of the drive circuit, and the output end of the voltage detection control circuit is connected in series between the LED load and the drive circuit. This solution adopts a voltage detection control circuit and connects the voltage detection control circuit in series between the drive circuit and the LED load. When a high voltage is input, the voltage detection control circuit is turned on to light up the LED load; when a low voltage is input, the voltage detection control circuit is not turned on to disconnect the LED load and not light up, thereby avoiding the LED lamp from heating up seriously when the power supply device is abnormal or low voltage in the power grid, affecting the service life of the LED lamp. However, this solution uses a set low-voltage protection threshold to make low-voltage judgments, which is aimed at the low voltage of the mains rather than the low voltage relative to the electrical equipment, and has poor adaptability.

[0005] The Chinese patent "A protection method for solar protection battery undervoltage circuit", publication number: CN106356977A, publication date: January 25, 2017, specifically discloses a photovoltaic panel, providing power and output voltage; a battery, providing power and output voltage; a selection circuit, when the photovoltaic panel and the battery are powered at the same time, it selects the higher voltage to conduct and outputs the conduction voltage; a power supply circuit, which receives the conduction voltage output by the selection circuit, and outputs the power supply voltage and the working voltage for the load; a main control circuit, which receives the power supply voltage output by the power supply circuit and outputs a level signal; a logic OR gate circuit, which receives the level signal after the output voltage of the photovoltaic panel is compared with the reference voltage, the output level signal of the battery and the output level signal of the main control circuit, performs an OR gate operation on the three level signals, and outputs a control signal to control the operation and failure of the power supply circuit. This scheme is to conduct by selecting a higher voltage between the photovoltaic panel and the battery, which is for undervoltage protection of the battery, not for protection of the load, and it is also unable to adaptively protect the load from operating in a non-working voltage environment according to the load condition. Summary of the invention

[0006] In order to solve the problem that the prior art cannot adapt to the load situation to avoid the load from operating in a non-working voltage environment, the present application provides an electrical equipment protection device, which outputs the voltage required for the normal operation of the electrical equipment as a reference voltage through the electrical equipment information. The control module performs judgment according to the reference voltage and the power supply end voltage, and outputs control signals corresponding to the power supply end voltage being less than the reference voltage and the power supply end voltage being greater than or equal to the reference voltage. The detection module and the switch module respectively operate upon receiving the control signal. The detection module outputs a load detection signal to let the user know the load power supply situation. The switch module respectively realizes the conduction or disconnection of the circuit from the electrical equipment to the power supply end according to different control signals, so that when the power supply end voltage does not meet the reference voltage, the circuit between the electrical equipment and the power supply end is disconnected, thereby preventing the electrical equipment from starting when the voltage cannot be met, thereby ensuring the normal operation of the user's equipment.

[0007] In order to achieve the above-mentioned technical objectives, a technical solution provided by the present application is a protection device for electrical equipment, which is connected to the electrical equipment and the power supply end, and includes: a reference module, which outputs a reference voltage according to the electrical equipment information; a control module, which is connected to the reference module and the power supply end, and outputs a control signal according to the reference voltage and the power supply end voltage; a detection module, which is connected to the control module, and acts based on the control signal of the control module to output a load detection signal; a switch module, which is connected to the electrical equipment and the control module, and acts based on the control signal of the control module to control the working state of the electrical equipment.

[0008] Furthermore, outputting a control signal according to the reference voltage and the power supply terminal voltage includes: outputting a first control signal when the power supply terminal voltage is greater than or equal to the reference voltage; and outputting a second control signal when the power supply terminal voltage is less than the reference voltage.

[0009] Furthermore, the control signal action based on the control module to control the working state of the electrical equipment includes: based on the first control signal, the switch module is turned on and the electrical equipment is in a normal working state; based on the second control signal, the switch module is turned off and the electrical equipment is in a non-working state.

[0010] Furthermore, it also includes: an auxiliary power supply module for providing auxiliary voltage.

[0011] Furthermore, the control module at least includes a comparison circuit connected to the power supply end; the comparison circuit at least includes a comparator, a first pin of the comparator is connected to the detection module and the switch module, a second pin of the comparator is connected to the reference module, a third pin of the comparator is connected to the positive pole of the power supply end, a fourth pin of the comparator is connected to the negative pole of the power supply end and grounded, and a fifth pin of the comparator is connected to the auxiliary power supply module.

[0012] Furthermore, the control module also includes a filter circuit connected to the power supply end; the filter circuit at least includes a filter capacitor, the positive electrode of the filter capacitor is connected to the positive electrode of the power supply end, and the negative electrode of the filter capacitor is connected to the negative electrode of the power supply end.

[0013] Furthermore, the detection module at least includes a detection circuit connected to the power supply end and the control module; the detection circuit at least includes a detection load, a first MOS tube and a first transistor, the base of the first transistor is connected to the first pin of the comparator, the emitter of the first transistor is connected to the source of the first MOS tube and is grounded, the collector of the first transistor is connected to the auxiliary power supply module, the gate of the first MOS tube is connected to the collector of the first transistor, the drain of the first MOS tube is connected to one end of the detection load, and the other end of the detection load is connected to the positive electrode of the power supply end and the electrical equipment.

[0014] Furthermore, the detection circuit also includes a first resistor and a second resistor, one end of the first resistor is connected to the auxiliary power supply module, the other end of the first resistor is connected to the collector of the first transistor, one end of the second resistor is connected to the gate of the first MOS tube, and the other end of the first resistor is connected to the emitter of the first transistor.

[0015] Furthermore, the switch module at least includes an operation control circuit connected to the electrical equipment; the operation control circuit at least includes a second MOS tube, a second triode and a third triode, the drain of the second MOS tube is connected to the electrical equipment, the source of the second MOS tube is connected to the collector of the second triode and grounded, the gate of the second MOS tube is connected to the emitter of the second triode, the base of the second triode is connected to the first pin of the comparator, the base of the third triode is connected to the first pin of the comparator, the emitter of the third triode is connected to the gate of the second MOS tube, and the collector of the third triode is connected to the auxiliary power supply module.

[0016] Furthermore, the switch module also includes a third resistor, one end of the third resistor is connected to the gate of the second MOS tube, and the other end of the third resistor is connected to the source of the second MOS tube.

[0017] The beneficial effects of the present application are as follows: the high and low levels output by the comparator OP1B are used to control the on and off of the detection circuit and the operation control circuit respectively, so that when the DC voltage at the power supply end is lower than the working voltage of the electrical equipment, the operation control circuit is cut off to prevent the electrical equipment from operating at too low a voltage, and at the same time, the detection circuit is turned on, and the detection of the DC at the power supply end by the detection load Rx can intuitively let the user know the state of the DC at the power supply end, so that the user can adjust the DC voltage at the power supply end to adapt to the operation of the electrical equipment. When the electrical equipment is operating normally, the detection circuit stops working, and the detection load Rx will not divide or shunt the voltage of the electrical equipment under normal operation, avoiding the impact on the operating requirements of the electrical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The schematic diagram of the circuit of a traditional power supply device for electrical equipment in the related technology.

[0019] Figure 2 This is a schematic diagram of the circuit structure of an electrical equipment protection device of the present application. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present application more clear, the present application is further described in detail below in conjunction with the drawings and examples. It should be understood that the specific implementation method described here is only an optimal embodiment of the present application, which is only used to explain the present application and does not limit the scope of protection of the present application. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0021] like Figure 2 As shown, a protection device for electrical equipment is connected to the electrical equipment and the power supply end, comprising: A reference module outputs a reference voltage according to the information of the electrical equipment; A control module is connected to the reference module and the power supply end, and outputs a control signal according to the reference voltage and the power supply end voltage; A detection module, connected to the control module, operates based on a control signal of the control module to output a load detection signal; The switch module is connected to the electrical device and the control module, and operates based on the control signal of the control module to control the working state of the electrical device.

[0022] In this embodiment, the voltage required for the normal operation of the electrical equipment is output through the electrical equipment information as a reference voltage. The control module performs judgment based on the reference voltage and the voltage at the power supply end, and outputs control signals corresponding to the power supply end voltage being less than the reference voltage and the power supply end voltage being greater than or equal to the reference voltage. The detection module and the switch module respectively operate upon receiving the control signal. The detection module outputs a load detection signal for the user to know the load power supply status. The switch module respectively realizes the conduction or disconnection of the circuit from the electrical equipment to the power supply end according to different control signals, so that when the voltage at the power supply end does not meet the reference voltage, the circuit between the electrical equipment and the power supply end is disconnected, thereby preventing the electrical equipment from starting when the voltage cannot be met, thereby ensuring the normal operation of the user's equipment.

[0023] The electrical equipment information at least includes the rated power of the electrical equipment or the working voltage of the electrical equipment. The reference module obtains the rated power of the electrical equipment or the working voltage of the electrical equipment, and outputs the reference voltage according to the rated power of the electrical equipment or the working voltage of the electrical equipment. The electrical equipment information can be manually input, or the reference module can be connected to the electrical equipment to obtain the electrical equipment information. The reference module and the electrical equipment can be electrically connected or communicated.

[0024] The control signal output according to the reference voltage and the power supply voltage includes: When the voltage at the power supply terminal is greater than or equal to the reference voltage, a first control signal is output; When the voltage at the power supply terminal is lower than the reference voltage, a second control signal is output.

[0025] Correspondingly, the control signal action based on the control module to output the load detection signal includes: Based on the second control signal, the detection module outputs a load detection signal.

[0026] The control signal actions based on the control module to control the working state of the electrical equipment include: Based on the first control signal, the switch module is turned on, and the electrical device is in a normal working state; Based on the second control signal, the switch module is turned off and the electrical device is in a non-working state.

[0027] In this embodiment, when the voltage at the power supply end is less than the reference voltage, the detection module outputs a load detection signal to prompt the user that the voltage at the power supply end is too low, and at the same time the switch module is disconnected, so that the power supply circuit of the electrical equipment is disconnected, and the electrical equipment is in a non-working state, so as to prevent the electrical equipment from operating under a voltage lower than the working voltage, thereby ensuring the safe operation of the electrical equipment. When the voltage at the power supply end is greater than or equal to the reference voltage, the detection module does not work, and at the same time the switch module is turned on, and the electrical equipment operates normally, which not only realizes the output of the load detection signal when the voltage at the power supply end is not satisfied, but also ensures that the detection module will not cause voltage division or current shunting when the electrical equipment operates normally, further ensuring the normal operation of the user's equipment.

[0028] As a second embodiment of the present application, an electrical equipment protection device further includes: Auxiliary power supply module, used to provide auxiliary voltage.

[0029] The auxiliary power supply module is respectively connected to the control module, the detection module and the switch module to meet the voltage requirements of the operations of each module.

[0030] In this embodiment, the auxiliary power supply module is a VCC power supply.

[0031] The control module at least includes a comparison circuit connected to the power supply end, and the comparison circuit at least includes a comparator OP1B, a first pin PIN1 of the comparator OP1B is connected to the detection module and the switch module, a second pin PIN2 of the comparator OP1B is connected to the reference module, a third pin PIN3 of the comparator OP1B is connected to the positive pole of the power supply end DC, a fourth pin PIN4 of the comparator OP1B is connected to the negative pole of the power supply end DC and grounded GND, and a fifth pin PIN8 of the comparator OP1B is connected to the auxiliary power supply module.

[0032] At this time, the first pin PIN1 of the comparator OP1B outputs the first control signal and the second control signal. The reference module outputs the reference voltage Vref to the comparator. If the DC voltage at the power supply end drops and is lower than the reference voltage Vref, the first pin PIN1 of the comparator OP1B outputs the second control signal, that is, the voltage of the third pin PIN3 of the comparator OP1B is lower than the voltage of the second pin PIN2 of the comparator OP1B, and the first pin PIN1 of the comparator OP1B outputs a low level signal to the detection module and the switch module.

[0033] Correspondingly, the detection module is configured to output a load detection signal when a low-level signal is received, and the switch module is configured to be cut off when a low-level signal is received, so that the power supply circuit of the electrical equipment Rload is disconnected, and the electrical equipment Rload cannot operate at a voltage lower than the working voltage.

[0034] In other cases, the control module further includes a filter circuit connected to the power supply end, the filter circuit at least includes a filter capacitor EC, the positive electrode of the filter capacitor EC is connected to the positive electrode of the power supply end DC, and the negative electrode of the filter capacitor EC is connected to the negative electrode of the power supply end DC.

[0035] By filtering the voltage at the power supply end through a filter capacitor, voltage fluctuations and noise are reduced, thereby improving the stability and reliability of the entire system. At the same time, it helps to improve the precision and accuracy of subsequent detection modules, avoids errors caused by voltage fluctuations, and ensures the credibility and effectiveness of the detection results.

[0036] The detection module at least includes a detection circuit connected to the power supply end DC and the control module, and the detection circuit at least includes a detection load Rx, a first MOS tube Q1 and a first triode Q3, the base of the first triode Q3 is connected to the first pin PIN1 of the comparator OP1B, the emitter of the first triode Q3 is connected to the source of the first MOS tube Q1 and is grounded, the collector of the first triode Q3 is connected to the auxiliary power supply module, the gate of the first MOS tube Q1 is connected to the collector of the first triode Q3, the drain of the first MOS tube Q1 is connected to one end of the detection load Rx, and the other end of the detection load Rx is connected to the positive electrode of the power supply end DC and the electrical equipment Rload.

[0037] In this embodiment, when the first pin PIN1 of the comparator OP1B outputs a low-level signal to the base of the first transistor Q3, the first transistor Q3 is not turned on, the voltage of the auxiliary power supply module controls the first MOS transistor Q1 to be turned on, the detection load Rx to GND loop is turned on, and the detection load Rx outputs a load detection signal; when the first pin PIN1 of the comparator OP1B outputs a high-level signal to the base of the first transistor Q3, the first transistor Q3 is turned on, at this time the gate voltage of the first MOS transistor Q1 is pulled down, the first MOS transistor Q1 is not turned on, the detection load Rx to GND loop is not turned on, the detection load Rx stops working, and the output of the load detection signal is not executed.

[0038] In other cases, the detection circuit also includes a first resistor R1 and a second resistor R2, one end of the first resistor R1 is connected to the auxiliary power supply module, the other end of the first resistor R1 is connected to the collector of the first transistor Q3, one end of the second resistor R2 is connected to the gate of the first MOS transistor Q1, and the other end of the first resistor R1 is connected to the emitter of the first transistor Q3.

[0039] The current limiting and voltage dividing effects of the first resistor R1 and the second resistor R2 improve the stability of the circuit. At the same time, the working states of the transistor and the MOS tube can be adjusted by adjusting the resistance values ​​of the resistors to meet the needs in different situations.

[0040] The switch module at least includes an operation control circuit connected to the electrical equipment Rload, and the operation control circuit at least includes a second MOS tube Q2, a second triode Q4 and a third triode Q5, the drain of the second MOS tube Q2 is connected to the electrical equipment Rload, the source of the second MOS tube Q2 is connected to the collector of the second triode Q4 and grounded, the gate of the second MOS tube Q2 is connected to the emitter of the second triode Q4, the base of the second triode Q4 is connected to the first pin PIN1 of the comparator OP1B, the base of the third triode Q5 is connected to the first pin PIN1 of the comparator OP1B, the emitter of the third triode Q5 is connected to the gate of the second MOS tube Q2, and the collector of the third triode Q5 is connected to the auxiliary power supply module.

[0041] In this embodiment, when the first pin PIN1 of the comparator OP1B outputs a low-level signal to the bases of the second transistor Q4 and the third transistor Q5, the second transistor Q4 is turned off, the third transistor Q5 is turned off, and the second MOS transistor Q2 is not turned on. At this time, a loop cannot be formed between the electrical device Rload and the power supply end DC, and the electrical device Rload is in a non-working state. When the first pin PIN1 of the comparator OP1B outputs a high-level signal to the bases of the second transistor Q4 and the third transistor Q5, the second transistor Q4 is turned on, the third transistor Q5 is turned on, and the second MOS transistor Q2 is turned on. At this time, the electrical device Rload can form a power supply loop with the power supply end DC, the electrical device Rload can work normally, and the electrical device Rload is in a normal working state.

[0042] In some other cases, the switch module further includes a third resistor R3, one end of the third resistor R3 is connected to the gate of the second MOS transistor Q2, and the other end of the third resistor R3 is connected to the source of the second MOS transistor Q2.

[0043] The current limiting and voltage dividing functions of the third resistor R3 further improve the stability of the circuit.

[0044] Specifically, the first MOS transistor Q1 is an N-channel field effect transistor, the second MOS transistor Q2 is an N-channel field effect transistor, the first transistor Q3 is an NPN transistor, the second transistor Q4 is a PNP transistor, and the third transistor Q5 is an NPN transistor.

[0045] In the present application, the high and low levels output by the comparator OP1B are used to control the on and off of the detection circuit and the operation control circuit respectively, so that when the DC voltage at the power supply end is lower than the working voltage of the power-consuming device Rload, the operation control circuit is cut off to prevent the power-consuming device Rload from operating at an excessively low voltage. At the same time, the detection circuit is turned on, and the detection of the DC at the power supply end by the detection load Rx can intuitively let the user know the state of the DC at the power supply end, so that the user can adjust the DC voltage at the power supply end to adapt to the operation of the power-consuming device Rload. When the power-consuming device Rload is operating normally, the detection circuit stops working, and the detection load Rx will not divide or shunt the voltage of the power-consuming device Rload under normal operation, so as to avoid affecting the operating requirements of the power-consuming device Rload.

[0046] The specific implementation described above is a preferred implementation of an electrical equipment protection device of the present application, and is not intended to limit the specific implementation scope of the present application. The scope of the present application includes but is not limited to the specific implementation embodiment. All equivalent changes made in accordance with the shape and structure of the present application are within the protection scope of the present application.

Claims

1. An electrical equipment protection device, connected to the electrical equipment and the power supply end, characterized in that: include: A reference module outputs a reference voltage according to the information of the electrical equipment; A control module is connected to the reference module and the power supply end, and outputs a control signal according to the reference voltage and the power supply end voltage; A detection module, connected to the control module, operates based on a control signal of the control module to output a load detection signal; The switch module is connected to the electrical device and the control module, and operates based on the control signal of the control module to control the working state of the electrical device.

2. The electrical equipment protection device according to claim 1, characterized in that: Outputting a control signal according to the reference voltage and the power supply terminal voltage includes: When the voltage at the power supply terminal is greater than or equal to the reference voltage, a first control signal is output; When the voltage at the power supply terminal is lower than the reference voltage, a second control signal is output.

3. The electrical equipment protection device according to claim 2, characterized in that: The control signal action based on the control module to control the working state of the electrical equipment includes: Based on the first control signal, the switch module is turned on, and the electrical device is in a normal working state; Based on the second control signal, the switch module is turned off and the electrical device is in a non-working state.

4. The electrical equipment protection device according to claim 1, characterized in that: Also includes: Auxiliary power supply module, used to provide auxiliary voltage.

5. The electrical equipment protection device according to claim 4, characterized in that: The control module at least includes a comparison circuit connected to the power supply end; The comparison circuit at least includes a comparator, a first pin of the comparator is connected to the detection module and the switch module, a second pin of the comparator is connected to the reference module, a third pin of the comparator is connected to the positive pole of the power supply end, a fourth pin of the comparator is connected to the negative pole of the power supply end and grounded, and a fifth pin of the comparator is connected to the auxiliary power supply module.

6. The electrical equipment protection device according to claim 5, characterized in that: The control module also includes a filter circuit connected to the power supply end; The filter circuit at least includes a filter capacitor, the positive electrode of the filter capacitor is connected to the positive electrode of the power supply end, and the negative electrode of the filter capacitor is connected to the negative electrode of the power supply end.

7. The electrical equipment protection device according to claim 4, characterized in that: The detection module at least includes a detection circuit connected to the power supply end and the control module; The detection circuit at least includes a detection load, a first MOS tube and a first triode, the base of the first triode is connected to the first pin of the comparator, the emitter of the first triode is connected to the source of the first MOS tube and is grounded, the collector of the first triode is connected to the auxiliary power supply module, the gate of the first MOS tube is connected to the collector of the first triode, the drain of the first MOS tube is connected to one end of the detection load, and the other end of the detection load is connected to the positive electrode of the power supply end and the electrical equipment.

8. The electrical equipment protection device according to claim 7, characterized in that: The detection circuit also includes a first resistor and a second resistor, one end of the first resistor is connected to the auxiliary power supply module, the other end of the first resistor is connected to the collector of the first transistor, one end of the second resistor is connected to the gate of the first MOS tube, and the other end of the first resistor is connected to the emitter of the first transistor.

9. The electrical equipment protection device according to claim 4, characterized in that: The switch module at least includes an operation control circuit connected to the electrical equipment; The operation control circuit at least includes a second MOS tube, a second triode and a third triode, the drain of the second MOS tube is connected to the electrical equipment, the source of the second MOS tube is connected to the collector of the second triode and is grounded, the gate of the second MOS tube is connected to the emitter of the second triode, the base of the second triode is connected to the first pin of the comparator, the base of the third triode is connected to the first pin of the comparator, the emitter of the third triode is connected to the gate of the second MOS tube, and the collector of the third triode is connected to the auxiliary power supply module.

10. An electrical equipment protection device as claimed in claim 9, characterized in that: The switch module further includes a third resistor, one end of the third resistor is connected to the gate of the second MOS tube, and the other end of the third resistor is connected to the source of the second MOS tube.

Images