A power supply circuit and an electric appliance

Abstract

This application discloses a power supply circuit and an electrical device. The power supply circuit includes a rectifier bridge, a voltage detection module, an energy storage module, a switching module, and a first capacitor. The input terminal of the rectifier bridge is connected to an AC power source, and the output terminal of the rectifier bridge is connected to the switching module. The switching module is also connected to the first capacitor and the energy storage module. The voltage detection module is connected to the input terminal of the rectifier bridge and the energy storage module. The rectifier bridge rectifies the AC power input from the AC power source and outputs DC power through the switching module to charge the first capacitor. The voltage detection module charges the energy storage module when the AC power exceeds a preset threshold voltage, causing the energy storage module to control the switching module to disconnect, thereby breaking the charging path of the first capacitor. This application can alleviate the problem of damage to the motherboard bus capacitors caused by overvoltage, and improve the reliability of the electrical device.

Description

Technical Field

[0001] This application relates to the field of electronic technology, specifically to a power supply circuit and electrical equipment. Background Technology

[0002] With the increasing prevalence and integration of functions in heating systems, overvoltage can cause the mainboard bus capacitors to operate under overvoltage conditions. When a heating system operates, it raises or lowers the water temperature to a certain level. Due to water's high specific heat capacity, the unit experiences a heavy load. If the capacitors operate under overvoltage conditions for extended periods, it will affect their lifespan, leading to capacitor bulging (an abnormal internal pressure causing the casing to expand, deform, or even rupture), and other damage, thus impacting the reliability of the heating system.

[0003] Therefore, the technology still needs to be improved and enhanced. Utility Model Content

[0004] This application provides a power supply circuit and electrical equipment that can alleviate the problem of motherboard bus capacitor damage caused by power supply overvoltage and improve the reliability of electrical equipment.

[0005] This application provides a power supply circuit, which includes a rectifier bridge, a voltage detection module, an energy storage module, a switching module, and a first capacitor; the input terminal of the rectifier bridge is connected to an AC power supply, the output terminal of the rectifier bridge is connected to the switching module, and the switching module is also connected to the first capacitor and the energy storage module; the voltage detection module is connected to the input terminal of the rectifier bridge and the energy storage module.

[0006] The rectifier bridge is used to rectify the AC power input from the AC power source and then output DC power through the switching module to charge the first capacitor; the voltage detection module is used to charge the energy storage module when the AC power is greater than the preset threshold voltage, so that the energy storage module controls the switching module to disconnect, thereby disconnecting the charging path of the first capacitor.

[0007] In some embodiments of the power supply circuit, the voltage detection module includes a first voltage regulator unit and a second voltage regulator unit connected in series; the energy storage module is connected in parallel with the second voltage regulator unit.

[0008] The first voltage regulator unit is used to provide a power supply path for the second voltage regulator unit when the AC voltage is greater than the first threshold voltage; the second voltage regulator unit is used to supply power to the energy storage module when the AC voltage is greater than the second threshold voltage; wherein, the preset threshold voltage is the larger value between the first threshold voltage and the second threshold voltage.

[0009] In some embodiments of the power supply circuit, the power supply circuit further includes a current limiting module, which is connected to the energy storage module and the switching module, and is used to provide current limiting protection for the switching module.

[0010] In some embodiments of the power supply circuit, the first voltage regulator unit includes a rectifier diode, a first current-limiting resistor, and a first Zener diode. The positive terminal of the rectifier diode is connected to the live wire of the AC power supply, the negative terminal of the rectifier diode is connected to the negative terminal of the first Zener diode through the first current-limiting resistor, and the positive terminal of the first Zener diode is connected to the second voltage regulator unit.

[0011] In some embodiments of the power supply circuit, the second voltage regulator unit includes a second Zener diode and a load resistor. The negative terminal of the second Zener diode is connected to the positive terminal of the first Zener diode, and the positive terminal of the second Zener diode is used to connect to the neutral terminal of the AC power supply. The load resistor is connected in parallel across the two ends of the second Zener diode.

[0012] In some embodiments of the power supply circuit, the switching module includes a normally closed relay. One end of the normally closed switch in the normally closed relay is connected to the output terminal of the rectifier bridge, and the other end of the normally closed switch in the normally closed relay is connected to the first capacitor. One end of the coil in the normally closed relay is connected to the current limiting module, and the other end of the coil in the normally closed relay is used to connect to the neutral terminal of the AC power supply.

[0013] In some embodiments of the power supply circuit, the current limiting module includes a second current limiting resistor, one end of which is connected to one end of the coil in a normally closed relay, and the other end of which is connected to the negative terminal of a second Zener diode.

[0014] In some embodiments of the power supply circuit, the energy storage module includes a second capacitor connected in parallel with a second Zener diode.

[0015] This application also provides an electrical device, which includes the power supply circuit described above.

[0016] In some embodiments, the electrical equipment includes at least an air conditioner and a heating unit.

[0017] This application provides a power supply circuit and electrical device. In the power supply circuit, when the AC input voltage to the rectifier bridge exceeds a preset threshold voltage, i.e., the power supply voltage is overvoltage, the voltage detection module charges the energy storage module, controls the energy storage module to enter the working state to supply power to the switching module, causing the switching module to open and thus cutting off the power supply path to the first capacitor. Therefore, the first capacitor stops working when the power supply voltage is overvoltage, thereby alleviating the problem of damage to the motherboard bus capacitors caused by overvoltage and improving the reliability of the electrical device. Attached Figure Description

[0018] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0019] Figure 1This is a first structural block diagram of a power supply circuit provided in an embodiment of this application.

[0020] Figure 2 This is a second structural block diagram of the power supply circuit provided in an embodiment of this application.

[0021] Figure 3 The circuit structure diagram of the power supply circuit provided in the embodiment of this application is shown. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Features thus defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0024] Please see Figure 1 This application provides a power supply circuit, which includes a rectifier bridge 10, a voltage detection module 20, an energy storage module 30, a switch module 40, and a first capacitor 50. The input terminal of the rectifier bridge 10 is connected to the live wire terminal (e.g., AC-L) and the neutral wire terminal (e.g., AC-N) of the AC power supply. The output terminal of the rectifier bridge 10 is connected to the switch module 40. The switch module 40 is also connected to the first capacitor 50 and the energy storage module 30. The voltage detection module 20 is connected to the input terminal of the rectifier bridge 10 and the energy storage module 30.

[0025] The first capacitor 50 can be a bus capacitor on the main board side of the electrical equipment. The rectifier bridge 10 rectifies the AC input and outputs DC power, which is then passed through the switch module 40 to the bus capacitor to charge it. The bus capacitor stores and filters the DC power to supply power to other loads in the electrical equipment. The voltage detection module 20, energy storage module 30, and switch module 40 serve as overvoltage protection in the power supply circuit. The voltage detection module 20 charges the energy storage module 30 when the AC voltage exceeds a preset threshold voltage, causing the energy storage module 30 to control the switch module 40 to disconnect, thus breaking the charging path of the first capacitor 50. In other words, when the AC input to the rectifier bridge 10 exceeds the preset threshold voltage, indicating an overvoltage, the voltage detection module 20 charges the energy storage module 30, controlling it to enter a working state and supply power to the switch module 40, causing the switch module 40 to disconnect and thus cutting off the power supply path to the first capacitor 50. Therefore, the first capacitor 50 stops working when the power supply voltage is overvoltage, which can alleviate the problem of the motherboard bus capacitor being easily damaged due to the overvoltage of the power supply and improve the reliability of electrical equipment.

[0026] Please see Figure 2 In some embodiments, the voltage detection module 20 includes a first voltage regulator unit 21 and a second voltage regulator unit 22 connected in series; the energy storage module 30 is connected in parallel with the second voltage regulator unit 22. The first voltage regulator unit 21 is used to provide a power supply path for the second voltage regulator unit 22 when the AC voltage is greater than a first threshold voltage; the second voltage regulator unit 22 is used to supply power to the energy storage module 30 when the AC voltage is greater than a second threshold voltage; wherein, the preset threshold voltage is the larger value of the first threshold voltage and the second threshold voltage.

[0027] In this embodiment, the voltage detection module 20 can realize voltage detection by setting two-stage voltage regulation units. When the AC voltage is greater than the larger value of the first threshold voltage and the second threshold voltage, the first voltage regulation unit 21 and the second voltage regulation unit 22 are ensured to enter the working state to supply power to the energy storage module 30, thereby triggering the switch module 40 to enter the working state and realizing effective protection of the first capacitor 50.

[0028] Please continue reading. Figure 2 In some embodiments, the power supply circuit also includes a current limiting module 60, which is connected to the energy storage module 30 and the switching module 40. The current limiting module 60 is used to provide current limiting protection for the switching module 40 to prevent excessive current from passing through the switching module 40 and damaging the switching module 40, thereby improving the reliability of the power supply circuit.

[0029] Please see Figure 3In one embodiment, the first voltage regulator unit 21 includes a rectifier diode D1, a first current-limiting resistor R1, and a first Zener diode DZ1. The anode of the rectifier diode D1 is connected to the live wire of the AC power supply, and the cathode of the rectifier diode D1 is connected to the cathode of the first Zener diode DZ1 through the first current-limiting resistor R1. The anode of the first Zener diode DZ1 is connected to the second voltage regulator unit 22. The first current-limiting resistor R1 provides current-limiting protection for the first voltage regulator unit 21, thereby improving its reliability.

[0030] As one embodiment, the second voltage regulator unit 22 includes a second Zener diode DZ2 and a load resistor R2. The negative terminal of the second Zener diode DZ2 is connected to the positive terminal of the first Zener diode DZ1, and the positive terminal of the second Zener diode DZ2 is used to connect to the neutral terminal of the AC power supply. The load resistor R2 is connected in parallel across the two ends of the second Zener diode DZ2.

[0031] In this embodiment, the rectifier diode D1 of the first voltage regulator unit 21 rectifies the AC power input to the rectifier bridge 10 and outputs it to the first voltage regulator diode DZ1. When the AC power is greater than the first threshold voltage, the first voltage regulator diode DZ1 is turned on. Similarly, when the AC power is greater than the second threshold voltage, the second voltage regulator diode DZ2 is turned on to charge the energy storage module 30. The first threshold voltage and the second threshold voltage may be different. To ensure that the switching module 40 is triggered when the power supply is overvoltage, the preset threshold voltage in this embodiment is the larger of the first threshold voltage and the second threshold voltage. Conversely, in this embodiment, the detection sensitivity can be adjusted by setting the magnitude of the first threshold voltage and the second threshold voltage.

[0032] The load resistor R2 can be connected to the power supply circuit as a load to improve circuit stability. Simultaneously, a detection terminal, such as the IN signal terminal, is led out from the load resistor R2 and connected to the controller. The controller detects the voltage value at the IN signal terminal, thereby detecting overvoltage, undervoltage, or normal AC power conditions. If the controller determines that the power supply voltage is overvoltage based on the IN signal terminal voltage value, in addition to triggering the switch module 40 to enter protection mode, the controller can also control other loads connected to the downstream of the first capacitor 50 to stop operating. Similarly, if the controller determines that the power supply voltage is undervoltage based on the IN signal terminal voltage value, the controller can directly control other electrical loads connected to the downstream of the first capacitor 50 to stop operating, thereby triggering the electrical equipment's protection mechanism.

[0033] Please continue reading. Figure 3In one embodiment, the switching module 40 includes a normally closed relay K1. One end of the normally closed switch in the normally closed relay K1 is connected to the output terminal of the rectifier bridge 10, and the other end of the normally closed switch in the normally closed relay K1 is connected to the first capacitor 50. One end of the coil in the normally closed relay K1 is connected to the current limiting module 60, and the other end of the coil in the normally closed relay K1 is used to connect to the neutral terminal of the AC power supply. The normally closed relay K1 is an electromagnetic switching device that remains closed in a conducting state when the relay is not energized, and switches to an open circuit state when energized.

[0034] The setting of the first and second threshold voltages ensures that when the AC current is within the normal voltage range, the first Zener diode DZ1 conducts while the second Zener diode DZ2 is cut off. At this time, the voltage of the energy storage module 30 cannot trigger the switching module 40, the normally closed relay K1 is closed, and the DC output from the rectifier bridge 10 can normally charge the first capacitor 50. Other electrical loads connected to the output of the rectifier bridge 10 in the electrical equipment operate normally. When the AC current is in an overvoltage state, both the first Zener diode DZ1 and the second Zener diode DZ2 work simultaneously. The energy storage module 30 begins charging, and the second Zener diode DZ2 clamps the voltage of the energy storage module 30 within a fixed voltage range. When the energy storage module 30 is charged to the operating voltage of the normally closed relay K1, the normally closed relay K1 starts working, its normally closed switch opens, disconnecting the charging circuit of the first capacitor 50 and effectively protecting the first capacitor 50. When the AC power is in an undervoltage state, both the first Zener diode DZ1 and the second Zener diode DZ2 are in the off state, and the energy storage module 30 has no corresponding voltage. At this time, if the voltage value of the load resistor R2 is detected to be less than a certain value, the controller will determine that the power supply circuit is in an undervoltage state. Then the controller will control the relevant electrical load to stop working, which is equivalent to triggering undervoltage protection, thereby improving the reliability of electrical equipment.

[0035] In one embodiment, the current limiting module 60 includes a second current limiting resistor R3. One end of the second current limiting resistor R3 is connected to one end of the coil in the normally closed relay K1, and the other end of the second current limiting resistor R3 is connected to the negative terminal of the second Zener diode DZ2. In this embodiment, the second current limiting resistor R3 is connected in series in the coil of the normally closed relay K1 to limit the current of the switching module 40 and thus protect the switching module 40.

[0036] As one embodiment, the energy storage module 30 includes a second capacitor connected in parallel with a second Zener diode DZ2. This embodiment achieves overvoltage protection for the power supply circuit through simple electronic device configuration, simplifying the circuit structure and reducing the space occupied by the circuit.

[0037] This application embodiment also provides an electrical device including the aforementioned power supply circuit. In the power supply circuit, when the AC input to the rectifier bridge exceeds a preset threshold voltage (i.e., the power supply voltage is overvoltage), the voltage detection module charges the energy storage module, controlling the energy storage module to enter a working state to supply power to the switching module, causing the switching module to disconnect and thus cutting off the power supply path to the first capacitor. Therefore, the first capacitor stops working when the power supply voltage is overvoltage, thereby alleviating the problem of damage to the motherboard bus capacitors caused by overvoltage and improving the reliability of the electrical device. Since the power supply circuit has been described in detail above, it will not be repeated here.

[0038] As one embodiment, the electrical equipment includes at least an air conditioner and a heating unit. That is, the power supply circuit in this embodiment can be used for overvoltage protection in the air conditioner or for overvoltage protection in the heating unit, which helps to improve the reliability of the air conditioner and the heating unit.

[0039] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0040] The power supply circuit provided in the embodiments of this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A power supply circuit, characterized in that, The power supply circuit includes a rectifier bridge, a voltage detection module, an energy storage module, a switching module, and a first capacitor; the input terminal of the rectifier bridge is connected to an AC power source, the output terminal of the rectifier bridge is connected to the switching module, and the switching module is also connected to the first capacitor and the energy storage module; the voltage detection module is connected to the input terminal of the rectifier bridge and the energy storage module. The rectifier bridge is used to rectify the AC power input from the AC power source and then output DC power through the switching module to charge the first capacitor; the voltage detection module is used to charge the energy storage module when the AC power is greater than a preset threshold voltage, so that the energy storage module controls the switching module to disconnect, thereby disconnecting the charging path of the first capacitor.

2. The power supply circuit according to claim 1, characterized in that, The voltage detection module includes a first voltage regulator unit and a second voltage regulator unit connected in series; the energy storage module is connected in parallel with the second voltage regulator unit. The first voltage regulator unit is used to provide a power supply path to the second voltage regulator unit when the AC voltage is greater than the first threshold voltage; the second voltage regulator unit is used to supply power to the energy storage module when the AC voltage is greater than the second threshold voltage; wherein, the preset threshold voltage is the larger value of the first threshold voltage and the second threshold voltage.

3. The power supply circuit according to claim 2, characterized in that, The power supply circuit also includes a current limiting module, which is connected to the energy storage module and the switching module. The current limiting module is used to provide current limiting protection for the switching module.

4. The power supply circuit according to claim 3, characterized in that, The first voltage regulator unit includes a rectifier diode, a first current-limiting resistor, and a first Zener diode. The anode of the rectifier diode is connected to the live wire of the AC power supply, the cathode of the rectifier diode is connected to the cathode of the first Zener diode through the first current-limiting resistor, and the anode of the first Zener diode is connected to the second voltage regulator unit.

5. The power supply circuit according to claim 4, characterized in that, The second voltage regulator unit includes a second Zener diode and a load resistor. The negative terminal of the second Zener diode is connected to the positive terminal of the first Zener diode, and the positive terminal of the second Zener diode is used to connect to the neutral terminal of the AC power supply. The load resistor is connected in parallel across the two ends of the second Zener diode.

6. The power supply circuit according to claim 5, characterized in that, The switching module includes a normally closed relay. One end of the normally closed switch in the normally closed relay is connected to the output terminal of the rectifier bridge, and the other end of the normally closed switch in the normally closed relay is connected to the first capacitor. One end of the coil in the normally closed relay is connected to the current limiting module, and the other end of the coil in the normally closed relay is used to connect to the neutral terminal of the AC power supply.

7. The power supply circuit according to claim 6, characterized in that, The current limiting module includes a second current limiting resistor, one end of which is connected to one end of the coil in the normally closed relay, and the other end of which is connected to the negative terminal of the second Zener diode.

8. The power supply circuit according to claim 6, characterized in that, The energy storage module includes a second capacitor, which is connected in parallel with the second Zener diode.

9. An electrical appliance, characterized in that, The electrical equipment includes a power supply circuit as described in any one of claims 1-8.

10. The electrical equipment according to claim 9, characterized in that, The electrical equipment includes at least air conditioners and heating units.

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