An inverter power supply

Abstract

The present application discloses an inverter power supply, which includes an energy storage module, a converter, a first switching unit, a second switching unit, and a protection module; the converter is electrically connected to the energy storage module and is used to be electrically connected to a power supply device and a load; the first switching unit is used to control the on / off of the power supply device and the converter; the second switching unit is used to cooperate with the first switching unit to control the on / off of the power supply device and the load; the protection module is used to detect a first alternating current voltage output by the power supply device when the first switching unit is in the on state, and make the second switching unit in the off state when the detected first alternating current voltage is greater than a first preset voltage, which can avoid damage to the load caused by the power supply device supplying power to the load when the first alternating current voltage is too large.

Description

Technical Field

[0001] This application relates to the technical field of power supplies, and particularly to an inverter power supply. Background Art

[0002] With the improvement of people's living standards, in order to cope with power outages, lack of power outdoors, inconvenient connection of power cords indoors, etc., inverter power supplies are used more and more widely. An inverter power supply can be charged and stored with electrical energy through a power supply device such as a power grid, and use the stored electrical energy to supply power to a load when needed. The inverter power supply has three working modes. The first is that the power supply device only supplies power to the inverter power supply. The second is that the inverter power supply supplies power to the load. The third is that the power supply device supplies power to both the inverter power supply and the load at the same time.

[0003] However, when the charging voltage provided by the power supply device is higher than the working voltage of the load, when the inverter power supply switches to the third working mode, the power supply device is turned on with the load and supplies power to the load, which easily causes the load to be damaged due to excessive voltage. Summary of the Invention

[0004] This application provides an inverter power supply, which can keep the power supply device and the load in a disconnected state when the charging voltage provided by the power supply device is higher than the working voltage of the load, so as to avoid damage to the load caused by the power supply device supplying power to the load when the first AC voltage is too high.

[0005] Specifically, an inverter power supply includes: an energy storage module for storing electrical energy; a converter electrically connected to the energy storage module and used for electrically connecting to a power supply device and a load; a first switch unit for controlling the on and off of the power supply device and the converter; a second switch unit for cooperating with the first switch unit to control the on and off of the power supply device and the load; a protection module for detecting the first AC voltage output by the power supply device when the first switch unit is in the on state, and making the second switch unit in the off state when the detected first AC voltage is greater than a first preset voltage.

[0006] The beneficial effect of this application is that when the protection module detects that the first AC voltage is greater than the first preset voltage, the protection module can enter the overvoltage protection state, so that the second switch unit is in the off state, so that the power supply device and the load are disconnected when the first AC voltage is too high, and it can avoid damage to the load caused by the power supply device directly supplying power to the load when the first AC voltage is too high. Description of the Drawings

[0007] To more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the following will briefly introduce the drawings required for use in the description of the embodiments or the related art. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0008] Figure 1 Schematic connection diagram of an inverter power supply, a load, and a power supply device in an embodiment of the present application;

[0009] Figure 2 Schematic connection diagram of a protection module, a converter, and a second switch unit in an embodiment of the present application;

[0010] Figure 3 Schematic circuit structure diagram of a voltage sampling unit in an embodiment of the present application;

[0011] Figure 4 Schematic circuit structure diagram of a judgment unit in an embodiment of the present application;

[0012] Figure 5 Schematic circuit structure diagram of a protection execution unit in an embodiment of the present application;

[0013] Figure 6 Schematic connection diagram of a protection execution unit and a second switch unit in an embodiment of the present application.

[0014] Reference numerals:

[0015] 10. Energy storage module; 20. Converter; 21. Control unit; 30. First switch unit; 40. Second switch unit; 50. Protection module; 51. Voltage sampling unit; 511. Voltage transformation circuit; 512. Rectification circuit; 512a. Full-bridge rectification circuit; 513. Sampling circuit; 52. Judgment unit; 53. Protection execution unit; 60. Power supply device; 70. Load; R1. First resistor; R2. Second resistor; R3. Third resistor; R4. Fourth resistor; R5. Fifth resistor; R6. Sixth resistor; R7. Seventh resistor; R8. Eighth resistor; R9. Ninth resistor; R10. Tenth resistor; R11. Eleventh resistor; R12. Twelfth resistor; R13. Thirteenth resistor; R14. Fourteenth resistor; R15. Fifteenth resistor; R16. Sixteenth resistor; C1. First capacitor; C2. Second capacitor; C3. Third capacitor; C4. Fourth capacitor; C5. Fifth capacitor; C6. Sixth capacitor; T1. First node; T2. Second node; T3. Third node; T4. Fourth node; T5. Fifth node; T6. Sixth node; T7. Seventh node; T8. Eighth node; D1. First diode; D2. Second diode; D3. Third diode; D4. Freewheeling diode; D5. First rectifier diode; D6. Second rectifier diode; D7. Third rectifier diode; D8. Fourth rectifier diode; L1. Primary winding; L2. Secondary winding; U1. First operational amplifier; U2. Second operational amplifier; U3. Comparator; Q1. First triode; Q2. Second triode; Ven. Enable signal; Vbk. Status signal; Vr. Control signal; Vs. Sampling voltage; UAC. First AC voltage. Detailed implementation manner

[0016] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0017] The present application provides an inverter power supply to solve the problem that when the charging voltage provided by the power supply device is higher than the operating voltage of the load, it is easy for the power supply device to supply power to the load and cause damage to the load.

[0018] As Figure 1 shown, the inverter power supply includes an energy storage module 10, a converter 20, a first switch unit 30 and a second switch unit 40.

[0019] Among them, the energy storage module 10 is used to store electrical energy. The energy storage module 10 can be a device such as a storage battery or an energy storage capacitor. The power supply device 60 can be used to charge the energy storage module 10. The energy storage module 10 storing electrical energy can supply power to the load 70 when the load 70 needs it. The specific model and power of the energy storage module 10 can be selected according to actual needs. The power supply device 60 can be the power grid, and the load 70 can be electrical appliances such as air conditioners, electric fans, computers, refrigerators, and mobile phones.

[0020] The converter 20 is electrically connected to the energy storage module 10 and is used to be electrically connected to the power supply device 60 and the load 70. Specifically, when the power supply device 60 charges the energy storage module 10, the converter 20 can convert the first alternating current voltage UAC output by the power supply device 60 into the first direct current voltage for charging the energy storage module 10. When the energy storage module 10 supplies power to the load 70, the converter 20 can also convert the second direct current voltage output by the energy storage module 10 into the second alternating current voltage for supplying power to the load 70. It should be noted that the converter 20 is a device that can realize the mutual conversion between alternating current and direct current. The specific working principle of the converter 20 has been publicly known in the related art and will not be elaborated in this application. The specific model and power of the converter 20 can be selected according to actual needs.

[0021] The first switch unit 30 is used to control the on-off between the power supply device 60 and the converter 20. The second switch unit 40 is used to cooperate with the first switch unit 30 to control the on-off between the power supply device 60 and the load 70. It should be noted that the inverter power supply has three working modes: charging mode, discharging mode, and bypass mode.

[0022] When the inverter power supply is in the charging mode, the first switch unit 30 is turned on and the second switch unit 40 is turned off. At this time, the power supply device 60 is connected to the converter 20, and the power supply device 60 is disconnected from the load 70. The first alternating current voltage UAC output by the power supply device 60 is converted into the first direct current voltage through the converter 20, and the first direct current voltage is used to charge the energy storage module 10.

[0023] When the inverter power supply is in the discharging mode, the first switch unit 30 is turned off and the second switch unit 40 is turned on. At this time, the power supply device 60 is disconnected from both the converter 20 and the load 70, and the converter 20 is connected to the load 70. The second direct current voltage output by the energy storage module 10 is converted into the second alternating current voltage through the converter 20, and the second alternating current voltage is used to supply power to the load 70.

[0024] When the inverter power supply is in the bypass mode, the first switch unit 30 is turned on, and the second switch unit 40 is turned on. At this time, the power supply device 60, the converter 20, and the load 70 are all turned on. The first AC voltage UAC output by the power supply device 60 is converted into a first DC voltage through the converter 20, and the energy storage module 10 is charged using the first DC voltage. At the same time, the first AC voltage UAC output by the power supply device 60 powers the load 70.

[0025] Continue to refer to Figure 1 As shown, the inverter power supply further includes a protection module 50.

[0026] Among them, the protection module 50 is used to detect the first AC voltage UAC output by the power supply device 60 when the first switch unit 30 is in the on state, and to turn the second switch unit 40 off when the detected first AC voltage UAC is greater than the first preset voltage. Among them, the first preset voltage can be the same as or close to the operating voltage of the load 70. Of course, the specific value of the first preset voltage can also be selected according to actual needs.

[0027] It should be noted that when the protection module 50 detects that the first AC voltage UAC is greater than the first preset voltage, the protection module 50 can enter the overvoltage protection state, making the second switch unit 40 in the off state. At this time, if the second switch unit 40 is in the off state, the protection module 50 keeps the second switch unit 40 in the off state. At this time, if the second switch unit 40 is in the on state, the protection module 50 controls the second switch unit 40 to disconnect, so that when the first AC voltage UAC is too large, the power supply device and the load 70 are in the disconnected state, thereby avoiding damage to the load 70 caused by the power supply device powering the load 70 when the first AC voltage UAC is too large.

[0028] It should also be noted that the protection module 50 only detects the first AC voltage UAC output by the power supply device 60 when the first switch unit 30 is in the on state. When the first switch unit 30 is in the off state, at this time the power supply device and the load 70 are in the disconnected state. Therefore, there is no need to detect the first AC voltage UAC output by the power supply device 60 at this time, which can reduce the power consumption of the protection module 50. At the same time, when the first switch unit 30 is in the off state, even if the first AC voltage UAC is too large, the protection module 50 will not control the second switch unit 40 to disconnect due to the excessive first AC voltage UAC, resulting in the energy storage module 10 being unable to supply power to the load 70 normally.

[0029] Specifically, the converter 20 can be electrically connected to the energy storage module 10, the power supply device 60, and the load 70. The first switch unit 30 can be electrically connected to the converter 20 and the power supply device 60. The second switch unit 40 can be electrically connected to the output end of the first switch unit 30, the load 70, and the converter 20. The protection module 50 can be electrically connected to the output end of the first switch unit 30 and the second switch unit 40.

[0030] In some embodiments of the present application, as Figure 2 shown, the protection module 50 includes a voltage sampling unit 51, a judgment unit 52, and a protection execution unit 53.

[0031] Among them, the voltage sampling unit 51 is configured to access the first AC voltage UAC output by the power supply device 60 when the first switch unit 30 is in the on state, and output a sampling voltage Vs according to the first AC voltage UAC. The magnitude of the sampling voltage Vs is proportional to the magnitude of the first AC voltage UAC. It can be understood that the magnitude of the sampling voltage Vs can represent the magnitude of the first AC voltage UAC. If the first AC voltage UAC is large, the sampling voltage Vs output by the voltage sampling unit 51 is large; if the first AC voltage UAC is small, the sampling voltage Vs output by the voltage sampling unit 51 is small.

[0032] The judgment unit 52 is configured to access the sampling voltage Vs and output a status signal Vbk according to the sampling voltage Vs.

[0033] The protection execution unit 53 is configured to access the status signal Vbk and output a control signal Vr for controlling the on / off of the second switch unit 40 to the second switch unit 40 according to the status signal Vbk.

[0034] Among them, the judgment unit 52 is further configured to output a first status signal Vbk when the sampling voltage Vs is greater than a second preset voltage, and the protection execution unit 53 is further configured to make the second switch unit 40 in the off state according to the first status signal Vbk. It can be understood that when the sampling voltage Vs is greater than the second preset voltage, it means that the first AC voltage UAC is greater than the first preset voltage. The specific value of the second preset voltage can be selected according to actual needs, and the present application does not make specific limitations.

[0035] It should be noted that the voltage sampling unit 51 can sample the first AC voltage UAC and output the corresponding sampling voltage Vs. The judgment unit 52 can output the first status signal Vbk when the sampling voltage Vs is greater than the second preset voltage. The protection execution unit 53 can make the second switch unit 40 in the off state according to the first status signal Vbk, so as to avoid damage to the load 70 caused by the power supply device directly supplying power to the load 70 when the first AC voltage UAC is too large.

[0036] Specifically, the voltage sampling unit 51 can be electrically connected to the output terminal of the first switch unit 30, the judgment unit 52 can be electrically connected to the voltage sampling unit 51, and the protection execution unit 53 can be electrically connected to the judgment unit 52 and the second switch unit 40.

[0037] In an embodiment of the present application, as Figure 3 shown, the voltage sampling unit 51 includes a voltage transformation circuit 511, a rectification circuit 512, and a sampling circuit 513.

[0038] The voltage transformation circuit 511 is configured to access the first AC voltage UAC output by the power supply device 60 when the first switch unit 30 is in the conducting state, and output a third AC voltage, where the third AC voltage is less than the first AC voltage UAC. The function of the voltage transformation circuit 511 is to sample the first AC voltage UAC output by the power supply device 60 and convert the first AC voltage UAC into a smaller third AC voltage, so as to achieve the goal of converting a high voltage into a low voltage, thereby meeting the range requirements of subsequent units and preventing subsequent units from being damaged due to excessive voltage.

[0039] The rectification circuit 512 is configured to access the third AC voltage and output a third DC voltage. The rectification circuit 512 can rectify the third AC voltage output by the voltage transformation circuit 511 to convert the third AC voltage into a third DC voltage, thereby facilitating the sampling of the sampling circuit 513.

[0040] The sampling circuit 513 is configured to access the third DC voltage and output a sampling voltage Vs. The sampling circuit 513 can collect and transform the third DC voltage and then output the corresponding sampling voltage Vs.

[0041] Specifically, the voltage transformation circuit 511 can be electrically connected to the output terminal of the first switch unit 30, the rectification circuit 512 can be electrically connected to the voltage transformation circuit 511, and the sampling circuit 513 can be electrically connected to the rectification circuit 512 and the judgment unit 52.

[0042] Continuing to refer to Figure 3 shown, in an embodiment of the present application, the voltage transformation circuit 511 can include a voltage transformer, and the voltage transformer includes a primary winding L1 and a secondary winding L2.

[0043] Among them, the primary winding L1 is electrically connected to the power supply device 60, and the primary winding L1 is configured to access the first AC voltage UAC; the secondary winding L2 cooperates with the primary winding L1, and the secondary winding L2 is configured to output a third AC voltage.

[0044] It should be noted that the voltage transformer can convert the first AC voltage UAC into a smaller third AC voltage according to a certain ratio. For example, if the first AC voltage UAC is 220V and the turn ratio of the primary winding L1 to the secondary winding L2 is 80:1, then the third AC voltage is 2.75V. The specific working principle of the voltage transformer has been publicly known in the related art and will not be elaborated in this application.

[0045] Continuing to refer to Figure 3 As shown, in an embodiment of the present application, the rectification circuit 512 includes a full-bridge rectification circuit 512a and a first capacitor C1.

[0046] Among them, the first input terminal and the second input terminal of the full-bridge rectification circuit 512a are electrically connected to the voltage transformation circuit 511 to access the third AC voltage; the first plate of the first capacitor C1 is electrically connected to the first output terminal of the full-bridge rectification circuit 512a and the sampling circuit 513, and the second plate of the first capacitor C1 is electrically connected to the second output terminal of the full-bridge rectification circuit 512a and the sampling circuit 513.

[0047] It can be understood that the full-bridge rectification circuit 512a can convert the third AC voltage into a pulsating DC voltage, and the pulsating DC voltage is then filtered by the first capacitor C1 to convert the pulsating DC voltage into a stable third DC voltage. The specific working principle of the full-bridge rectification circuit 512a has been publicly known in the related art and will not be elaborated in this application. The capacitance of the first capacitor C1 can be 10 μF. Of course, the capacitance of the first capacitor C1 can also be selected according to actual needs.

[0048] Specifically, the first input terminal of the full-bridge rectification circuit 512a can be electrically connected to the first end of the secondary winding L2, and the second input terminal of the full-bridge rectification circuit 512a can be electrically connected to the second end of the secondary winding L2.

[0049] More specifically, the full-bridge rectification circuit 512a includes a first rectifying diode D5, a second rectifying diode D6, a third rectifying diode D7, and a fourth rectifying diode D8. The positive electrode of the first rectifying diode D5, the negative electrode of the second rectifying diode D6, and the first end of the secondary winding L2 are electrically connected to a fifth node T5. The positive electrode of the third rectifying diode D7, the negative electrode of the fourth rectifying diode D8, and the second end of the secondary winding L2 are electrically connected to a sixth node T6. The negative electrode of the first rectifying diode D5, the negative electrode of the third rectifying diode D7, and the first plate of the first capacitor C1 are electrically connected to a seventh node T7. The positive electrode of the second rectifying diode D6, the positive electrode of the fourth rectifying diode D8, and the second plate of the first capacitor C1 are electrically connected to an eighth node T8.

[0050] It can be understood that the fifth node T5 is the first input terminal of the full-bridge rectifier circuit 512a, the sixth node T6 is the second input terminal of the full-bridge rectifier circuit 512a, the seventh node T7 is the first output terminal of the full-bridge rectifier circuit 512a, and the eighth node T8 is the second output terminal of the full-bridge rectifier circuit 512a.

[0051] Continue to refer to Figure 3 As shown, the rectifier circuit 512 may further include a first resistor R1; wherein, the first end of the first resistor R1 is electrically connected to the first plate of the first capacitor C1 and the first output terminal of the full-bridge rectifier circuit 512a, and the second end of the first resistor R1 is electrically connected to the second plate of the first capacitor C1 and the second output terminal of the full-bridge rectifier circuit 512a.

[0052] It should be noted that the first resistor R1 can provide a discharge path for the first capacitor C1. When the power supply device 60 is turned off, the third AC voltage connected to the rectifier circuit 512 becomes smaller. At this time, the first capacitor C1 can discharge through the first resistor R1, so that the internal voltage of the first resistor R1 drops synchronously to be consistent with the change of the third AC voltage. The resistance value of the first resistor R1 can be 100 KΩ. Of course, the resistance value of the first resistor R1 can also be selected according to actual needs.

[0053] Continue to refer to Figure 3 As shown, in an embodiment of the present application, the sampling circuit 513 includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, and a first operational amplifier U1.

[0054] Among them, the first end of the second resistor R2 is electrically connected to the rectifier circuit 512, the second end of the second resistor R2 is electrically connected to the positive input terminal of the first operational amplifier U1, and the second end of the second resistor R2 and the positive input terminal of the first operational amplifier U1 are grounded through the fourth resistor R4; the first end of the third resistor R3 is electrically connected to the rectifier circuit 512, the second end of the third resistor R3 is electrically connected to the negative input terminal of the first operational amplifier U1, and the second end of the third resistor R3 and the negative input terminal of the first operational amplifier U1 are electrically connected to the output terminal of the first operational amplifier U1 at the first node T1 through the fifth resistor R5.

[0055] It can be understood that the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5, and the first operational amplifier U1 form a differential sampling (ratio operation) circuit. The differential sampling circuit can achieve voltage stabilization control. After collecting and transforming the connected third DC voltage, a voltage suitable for op-amp processing can be output through the output terminal of the first operational amplifier U1.

[0056] It should be noted that the resistance values of the second resistor R2, the third resistor R3, the fourth resistor R4, and the fifth resistor R5 can all be 10 KΩ. Of course, the resistance values of the second resistor R2, the third resistor R3, the fourth resistor R4, and the fifth resistor R5 can also be selected according to actual requirements.

[0057] Specifically, the first end of the second resistor R2 can be electrically connected to the first electrode plate of the first capacitor C1, and the first end of the third resistor R3 can be electrically connected to the second electrode plate of the first capacitor C1.

[0058] Continue to refer to Figure 3 As shown, the sampling circuit 513 may further include a second capacitor C2 and a third capacitor C3.

[0059] Among them, the second capacitor C2 is connected in parallel with the fourth resistor R4, and the third capacitor C3 is connected in parallel with the fifth resistor R5. The second capacitor C2 and the third capacitor C3 are both filter capacitors, which can reduce the interference components doped in the voltage output from the output end of the first operational amplifier U1 to improve the accuracy of the sampling voltage Vs. The capacitances of the second capacitor C2 and the third capacitor C3 can both be 100 pF. Of course, the capacitances of the second capacitor C2 and the third capacitor C3 can also be selected according to actual requirements.

[0060] Continue to refer to Figure 3 As shown, the sampling circuit 513 may further include a second operational amplifier U2, a first diode D1, and a second diode D2.

[0061] Among them, the non-inverting input terminal of the second operational amplifier U2 is electrically connected to the first node T1, the inverting input terminal of the second operational amplifier U2, the output terminal of the second operational amplifier U2, the positive electrode of the first diode D1, and the negative electrode of the second diode D2 are electrically connected to the second node T2. The negative electrode of the first diode D1 is connected to the first reference voltage Vref1, the positive electrode of the second diode D2 is grounded to GND, and the second node T2 is electrically connected to the judgment unit 52. The second node T2 is used to output the sampling voltage Vs.

[0062] It should be noted that the second operational amplifier U2, the first diode D1, and the second diode D2 can form a voltage follower circuit. The voltage follower circuit can achieve the function of voltage following, can isolate the influence between the front and rear stages, and greatly reduce the influence of the impedance of the subsequent circuit on the sampling voltage Vs. The first reference voltage Vref1 can be 3.3 V. Of course, the first reference voltage Vref1 can also be selected according to actual requirements.

[0063] Furthermore, continue to refer to Figure 3 As shown, the sampling circuit 513 may further include a sixth resistor R6, a seventh resistor R7, and a fourth capacitor C4.

[0064] Among them, the sixth resistor R6 is connected in series between the first node T1 and the non-inverting input terminal of the second operational amplifier U2. The first end of the sixth resistor R6 is electrically connected to the first node T1, and the second end of the sixth resistor R6 is electrically connected to the first end of the seventh resistor R7, the first plate of the fourth capacitor C4, and the non-inverting input terminal of the second operational amplifier U2. The second end of the second resistor R2 is electrically connected to the second plate of the fourth capacitor C4 and grounded to GND.

[0065] It should be noted that both the sixth resistor R6 and the seventh resistor R7 are voltage-dividing resistors, which can reduce the voltage output by the first operational amplifier U1 according to a certain amplitude ratio and then output it to the subsequent stage to meet the range requirements of the subsequent stage circuit. For example, if the voltage input to the sixth resistor R6 is 5V, the voltage output from the sixth resistor R6 can be 3V. At the same time, the sixth resistor and the fourth capacitor C4 form an RC filter, which can reduce the interference components doped in the sampling voltage Vs. The resistance value of the sixth resistor R6 can be 20KΩ, and the resistance value of the seventh resistor R7 can be 30KΩ. Of course, the resistance values of the sixth resistor R6 and the seventh resistor R7 can also be selected according to actual needs. The capacitance of the fourth capacitor C4 can be 100nF. Of course, the capacitance of the fourth capacitor C4 can also be selected according to actual needs.

[0066] In some embodiments of the present application, as Figure 4 shown, the judgment unit 52 includes a comparator U3, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11.

[0067] Among them, the first end of the eighth resistor R8 is electrically connected to the second node T2 for accessing the sampling voltage Vs, the second end of the eighth resistor R8 is electrically connected to the non-inverting input terminal of the comparator U3, the first end of the ninth resistor R9 accesses the second reference voltage Vref2, the second end of the ninth resistor R9 is electrically connected to the inverting input terminal of the comparator U3, the first end of the tenth resistor R10, the output terminal of the comparator U3, and the first end of the eleventh resistor R11 are electrically connected to the third node T3, the second end of the tenth resistor R10 accesses the third reference voltage Vref3, the second end of the eleventh resistor R11 is grounded to GND, and the third node T3 is electrically connected to the protection execution unit 53. The third node T3 is used to output the status signal Vbk.

[0068] It can be understood that the comparator U3, the eighth resistor R8, the ninth resistor R9, the tenth resistor R10, and the eleventh resistor R11 can form a judgment circuit. The comparator U3 can compare the sampled voltage Vs collected by the voltage sampling unit 51 with the preset threshold voltage of the judgment circuit. When the sampled voltage Vs is lower than the threshold voltage, the comparator U3 outputs a low potential, and the potential of the third node T3 is pulled down. At this time, the status signal Vbk output by the third node T3 is a low potential, indicating that the first AC voltage UAC output by the power supply device 60 is less than the first preset voltage, and the protection module 50 can be in the normal working mode. When the sampled voltage Vs is higher than the threshold voltage, the comparator U3 outputs a high potential, and the voltage at the third node T3 is pulled up to the third reference voltage Vref3 through the tenth resistor R10. At this time, the status signal Vbk output by the third node T3 is a high potential, indicating that the first AC voltage UAC output by the power supply device 60 is higher than the first preset voltage, and the protection module 50 needs to enter the overvoltage protection state to make the second switch unit 40 in the off state.

[0069] It should also be noted that the second reference voltage Vref2 and the third reference voltage Vref3 can both be 3.3V, and the threshold voltage can be 1.4V. Of course, the second reference voltage Vref2, the third reference voltage Vref3, and the threshold voltage can also be selected according to actual needs. The eighth resistor R8 can divide the voltage and protect the non-inverting input terminal of the comparator U3. The ninth resistor R9 can divide the second reference voltage Vref2 to obtain the expected threshold voltage. The tenth resistor R10 and the eleventh resistor R11 can play a role in voltage division and protection, and at the same time can adjust the voltage at the third node T3. The resistance value of the eighth resistor R8 can be 10KΩ, the resistance value of the ninth resistor R9 can be 27KΩ, the resistance value of the tenth resistor R10 can be 2KΩ, and the resistance value of the eleventh resistor R11 can be 10KΩ. Of course, the resistance values of the eighth resistor R8, the ninth resistor R9, the tenth resistor R10, and the eleventh resistor R11 can also be selected according to actual needs.

[0070] Further, continue to refer to Figure 4 As shown, the judgment unit 52 can further include a third diode D3 and a twelfth resistor R12.

[0071] Among them, the positive electrode of the third diode D3 is electrically connected to the third node T3, and the negative electrode of the third diode D3 is electrically connected to the second end of the eighth resistor R8 and the non-inverting input terminal of the comparator U3 through the twelfth resistor R12.

[0072] It can be understood that when the sampling voltage Vs exceeds the threshold voltage, the voltage at the output end of the comparator U3 (i.e., the voltage at the third node T3) changes from a low potential to a high potential, and the current generated by the third reference voltage Vref3 through the tenth resistor R10 is no longer absorbed by the comparator U3, but flows to the eighth resistor R8 through the third diode D3 and the twelfth resistor R12 in sequence, and the voltage across the eighth resistor R8 is increased on the original basis, and finally the function of the hysteresis comparator U3 is realized, that is, after the sampling voltage Vs exceeds the threshold voltage, when the sampling voltage Vs becomes less than the threshold voltage again, the voltage of the state signal Vbk output by the judgment unit 52 will not be immediately pulled down, so that the protection module 50 cannot immediately release the overvoltage protection state, but needs the sampling voltage Vs to continue to drop by a certain voltage value before the protection module 50 can release the overvoltage protection state and return to the normal working mode, so that the protection module 50 can be prevented from frequently switching between the overvoltage protection state and the normal working mode when the sampling voltage Vs is near the threshold voltage, thereby preventing the protection module 50 from causing a poor impact on the stable operation of the device.

[0073] Continue to see Figure 4 As shown, in an implementation of the present application, the determination unit 52 further includes a thirteenth resistor R13 and a fifth capacitor C5.

[0074] The first end of the thirteenth resistor R13 is electrically connected to the second end of the ninth resistor R9, the inverting input end of the comparator U3 and the first plate of the fifth capacitor C5, and the second end of the thirteenth resistor R13 is connected in parallel to the second plate of the fifth capacitor C5 and grounded GND.

[0075] The thirteenth resistor R13 and the ninth resistor R9 can form a voltage divider circuit, which can divide the second reference voltage Vref2 to obtain an expected threshold voltage, and the fifth capacitor C5 and the ninth resistor R9 can form an RC filter, which can reduce the interference components doped in the state signal Vbk. The resistance value of the thirteenth resistor R13 can be 20KΩ. Of course, the resistance value of the thirteenth resistor R13 can also be selected according to actual needs. The capacity of the fifth capacitor C5 can be 100nF. Of course, the capacity of the fifth capacitor C5 can also be selected according to actual needs.

[0076] In some embodiments of the present application, Figure 5 As shown, the protection execution unit 53 includes a first transistor Q1 and a second transistor Q2.

[0077] Among them, the base of the first triode Q1 is electrically connected to the third node T3 for accessing the status signal Vbk. The emitter of the first triode Q1 is grounded to GND. The collector of the first triode Q1 is electrically connected to the base of the second triode Q2 at the fourth node T4. An enable signal Ven is accessed at the fourth node T4. The enable signal Ven is used to control the on / off of the second triode Q2. The emitter of the second triode Q2 is grounded to GND. The collector of the second triode Q2 is used to output a control signal Vr.

[0078] It can be understood that the function of the protection execution unit 53 is to output a control signal Vr according to the enable signal Ven and the status signal Vbk, and use the control signal Vr to control the second switch unit 40. When the status signal Vbk is at a low potential, the first triode Q1 is turned off. At this time, the on / off of the second triode Q2 is controlled by the enable signal Ven. When the enable signal Ven is at a high potential, the second triode Q2 is turned on. The collector of the second triode Q2 is turned on with the GND terminal and outputs a first control signal Vr. The first control signal Vr controls the second switch unit 40 to turn on. When the enable signal Ven is at a low potential, the second triode Q2 is turned off. The collector of the second triode Q2 is disconnected from the GND terminal and outputs a second control signal Vr. The second control signal Vr controls the second switch unit 40 to turn off.

[0079] When the status signal Vbk is at a high potential, the first triode Q1 is turned on, and the potential of the fourth node T4 is quickly pulled down, causing the second triode Q2 to enter the off state. As a result, the collector of the second triode Q2 is disconnected from the GND terminal and outputs a second control signal Vr. The second control signal Vr controls the second switch unit 40 to turn off so that the power supply device 60 and the load 70 are in a disconnected state.

[0080] Furthermore, as Figure 5 shown, the protection execution unit 53 may further include a fourteenth resistor R14 and a sixth capacitor C6.

[0081] Among them, the first end of the fourteenth resistor R14 is electrically connected to the fourth node T4. The second end of the fourteenth resistor R14 is electrically connected to the emitter of the first triode Q1 and grounded to GND. The sixth capacitor C6 is connected in parallel with the fourteenth resistor R14.

[0082] It can be understood that the sixth capacitor C6 can filter the status signal Vbk, reducing the interference components in the status signal Vbk. The capacitance of the sixth capacitor C6 can be 1 nF. Of course, the capacitance of the sixth capacitor C6 can also be selected according to actual requirements. The fourteenth resistor R14 can be the discharge path for the sixth capacitor C6. The sixth capacitor C6 can discharge through the fourteenth resistor R14. The resistance value of the fourteenth resistor R14 can be 10 KΩ. Of course, the resistance value of the fourteenth resistor R14 can also be selected according to actual requirements.

[0083] Continuing to refer to Figure 5 As shown, in an embodiment of the present application, the protection execution unit 53 may further include a fifteenth resistor R15 and a sixteenth resistor R16. The fifteenth resistor R15 is connected in series between the third node T3 and the base of the first triode Q1. The sixteenth resistor R16 is connected in series between the access terminal of the protection execution unit 53 for accessing the enable signal Ven and the fourth node T4. The fifteenth resistor R15 is used to protect the first triode Q1, and the sixteenth resistor R16 is used to protect the second triode Q2. The resistance values of the fifteenth resistor R15 and the sixteenth resistor R16 can be 2 KΩ. Of course, the resistance values of the fifteenth resistor R15 and the sixteenth resistor R16 can also be selected according to actual requirements.

[0084] In an embodiment of the present application, continuing to refer to Figure 5 As shown, the converter 20 may include a control unit 21. The control unit 21 is electrically connected to the fourth node T4, and the control unit 21 is used to output an enable signal Ven to the fourth node T4.

[0085] It can be understood that since the enable signal Ven is provided by the control unit 21 of the converter 20, when the status signal Vbk is at a low potential, the converter 20 can control the on / off of the second switch unit 40 through the enable signal Ven. When the status signal Vbk is at a high potential, that is, when the first AC voltage UAC is greater than the first preset voltage, the protection module 50 can actively and quickly keep the second switch unit 40 in an off state and maintain the off state of the second switch unit 40. At this time, the converter 20 cannot control the second switch unit 40 to close, so as to ensure that the connection between the power supply device 60 and the load 70 can be quickly cut off when the first AC voltage UAC is too high. When the first AC voltage UAC drops to a predetermined potential, the protection module 50 ends the off control of the second switch unit 40. At this time, the on / off of the second switch unit 40 can be continued to be controlled by the converter 20.

[0086] Among them, the third node T3 of the determination unit 52 can also be electrically connected to the control unit 21 of the converter 20. The determination unit 52 is configured to send the status signal Vbk to the control unit 21 of the converter 20 when outputting the status signal Vbk to the protection execution unit 53, so that the converter 20 makes a corresponding response. For example, the control unit 21 of the converter 20 stops outputting the enable signal Ven when receiving the status signal Vbk.

[0087] In an embodiment of the present application, the first switch unit 30 and the second switch unit 40 may both include relays. It can be understood that the first switch unit 30 is turned on when the coil of the first switch unit 30 is energized, and the first switch unit 30 is turned off when the coil of the first switch unit 30 is de-energized. Similarly, the second switch unit 40 is turned on when the coil of the second switch unit 40 is energized, and the second switch unit 40 is turned off when the coil of the second switch unit 40 is de-energized.

[0088] As Figure 6 shown, the collector of the second triode Q2 can be electrically connected to the first end of the coil of the second switch unit 40, and the second end of the coil of the second switch unit 40 is connected to the fourth reference voltage Vref4. When the second switch unit 40 is turned on, the coil of the second switch unit 40 is energized and the second switch unit 40 is closed. The fourth reference voltage Vref4 can be 12V. Of course, the fourth reference voltage Vref4 can also be selected according to actual requirements.

[0089] Continue to refer to Figure 6 shown, the protection execution unit 53 may further include a freewheeling diode D4. The freewheeling diode D4 is connected in parallel with the coil of the second switch unit 40. The positive electrode of the freewheeling diode D4 is electrically connected to the first end of the coil of the second switch unit 40, and the negative electrode of the freewheeling diode D4 is electrically connected to the second end of the coil of the second switch unit 40. After the second triode Q2 is turned off, the freewheeling diode D4 can provide a freewheeling path for the coil of the second switch unit 40 to prevent the coil of the second switch unit 40 from being damaged due to excessive voltage excited by voltage mutation.

[0090] Refer to Figure 3 and Figure 6 shown, in an embodiment of the present application, the working process of the protection module 50 can be as follows:

[0091] The first switch unit 30 is closed, and the primary winding L1 is connected to the first AC voltage UAC output by the power supply device 60. Through electromagnetic induction, the secondary winding L2 outputs a third AC voltage. After the third AC voltage is filtered by the full-bridge rectifier circuit 512a and the first capacitor C1, it is converted into a stable third DC voltage. Subsequently, after the first operational amplifier U1 collects and transforms the third DC voltage, the output terminal of the first operational amplifier U1 outputs a voltage suitable for operational amplifier processing to the first node T1. The voltage at the first node T1 is divided and filtered by the sixth resistor R6, the seventh resistor R7, and the fourth capacitor C4, and then voltage-followed by the second budget amplifier. The output terminal of the second budget amplifier stably outputs the sampling voltage Vs, and the magnitude of the sampling voltage Vs is proportional to the magnitude of the first AC voltage UAC.

[0092] Subsequently, the positive input terminal of the comparator U3 is connected to the sampling voltage Vs. When the sampling voltage Vs is lower than the threshold voltage, it indicates that the first AC voltage UAC output by the power supply device 60 is less than the first preset voltage. At this time, the comparator U3 outputs a low potential, and the potential of the third node T3 is pulled down. At this time, the third node T3 outputs a status signal Vbk with a low potential, and the first triode Q1 is in an off state. At this time, the on / off of the second triode Q2 is controlled by the enable signal Ven output by the control unit 21 of the converter 20. When the enable signal Ven is at a high potential, the second triode Q2 is turned on, and the collector of the second triode Q2 is connected to the ground GND terminal and outputs the first control signal Vr. The coil of the second switch unit 40 is energized, and the second switch unit 40 is closed; when the enable signal Ven is at a low potential, the second triode Q2 is turned off, the collector of the second triode Q2 is disconnected from the ground GND terminal and outputs the second control signal Vr, the coil of the second switch unit 40 is de-energized, and the second switch unit 40 is opened.

[0093] When the sampling voltage Vs is higher than the threshold voltage, it indicates that the first AC voltage UAC output by the power supply device 60 is greater than the first preset voltage. At this time, the first triode Q1 is turned on, and the potential of the fourth node T4 is quickly pulled down, causing the second triode Q2 to enter an off state. As a result, the collector of the second triode Q2 is disconnected from the ground GND terminal and outputs the second control signal Vr. The coil of the second switch unit 40 remains de-energized, the second switch unit 40 remains open, and at this time, the converter 20 cannot control the second switch unit 40 to close.

[0094] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. An inverter power supply, characterized in that, Comprising: An energy storage module for storing electrical energy; A converter electrically connected to the energy storage module and configured to be electrically connected to a power supply device and a load; A first switch unit for controlling the connection and disconnection between the power supply device and the converter; A second switch unit for cooperating with the first switch unit to control the connection and disconnection between the power supply device and the load; A protection module for detecting a first AC voltage output by the power supply device when the first switch unit is in a conducting state, and when the detected first AC voltage is greater than a first preset voltage, causing the second switch unit to be in an off state and the first switch unit to be in a conducting state.

2. The inverter power supply according to claim 1, characterized in that, The protection module includes: A voltage sampling unit for accessing the first AC voltage output by the power supply device when the first switch unit is in a conducting state and outputting a sampling voltage according to the first AC voltage, the magnitude of the sampling voltage being proportional to the magnitude of the first AC voltage; A judgment unit for accessing the sampling voltage and outputting a status signal according to the sampling voltage; A protection execution unit for accessing the status signal and outputting a control signal for controlling the connection and disconnection of the second switch unit to the second switch unit according to the status signal; Wherein, the judgment unit is further configured to output a first status signal when the sampling voltage is greater than a second preset voltage, and the protection execution unit is further configured to cause the second switch unit to be in an off state according to the first status signal.

3. The inverter power supply according to claim 2, wherein, The voltage sampling unit includes: A voltage transformation circuit for accessing the first AC voltage output by the power supply device when the first switch unit is in a conducting state and outputting a third AC voltage, the third AC voltage being less than the first AC voltage; A rectification circuit for accessing the third AC voltage and outputting a third DC voltage; A sampling circuit for accessing the third DC voltage and outputting the sampling voltage.

4. The inverter power supply according to claim 3, characterized in that The rectification circuit includes a full-bridge rectification circuit and a first capacitor; Wherein, a first input terminal and a second input terminal of the full-bridge rectification circuit are electrically connected to the voltage transformation circuit to access the third AC voltage; a first electrode plate of the first capacitor is electrically connected to a first output terminal of the full-bridge rectification circuit and the sampling circuit, and a second electrode plate of the first capacitor is electrically connected to a second output terminal of the full-bridge rectification circuit and the sampling circuit.

5. The inverter power supply according to claim 3, characterized in that, The sampling circuit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor and a first operational amplifier; Wherein, the first end of the second resistor is electrically connected to the rectifying circuit, the second end of the second resistor is electrically connected to the positive input terminal of the first operational amplifier, and the second end of the second resistor and the positive input terminal of the first operational amplifier are grounded through the fourth resistor; the first end of the third resistor is electrically connected to the rectifying circuit, the second end of the third resistor is electrically connected to the negative input terminal of the first operational amplifier, and the second end of the third resistor and the negative input terminal of the first operational amplifier are electrically connected to the output terminal of the first operational amplifier at a first node through the fifth resistor.

6. The inverter power supply according to claim 5, characterized in that, The sampling circuit further includes a second operational amplifier, a first diode, and a second diode; Wherein, the positive input terminal of the second operational amplifier is electrically connected to the first node, the negative input terminal of the second operational amplifier, the output terminal of the second operational amplifier, the anode of the first diode, and the cathode of the second diode are electrically connected to a second node, the cathode of the first diode is connected to a first reference voltage, the anode of the second diode is grounded, the second node is electrically connected to the judgment unit, and the second node is used for outputting the sampling voltage.

7. The inverter power supply according to claim 6, characterized in that The judgment unit includes a comparator, an eighth resistor, a ninth resistor, a tenth resistor, and an eleventh resistor; Wherein, the first end of the eighth resistor is electrically connected to the second node for accessing the sampling voltage, the second end of the eighth resistor is electrically connected to the positive-phase input terminal of the comparator, the first end of the ninth resistor is connected to a second reference voltage, the second end of the ninth resistor is electrically connected to the inverting input terminal of the comparator, the first end of the tenth resistor, the output terminal of the comparator, and the first end of the eleventh resistor are electrically connected to a third node, the second end of the tenth resistor is connected to a third reference voltage, the second end of the eleventh resistor is grounded, the third node is electrically connected to the protection execution unit, and the third node is used for outputting the status signal.

8. The inverter power supply according to claim 7, wherein, The judgment unit further includes a third diode and a twelfth resistor; Wherein, the anode of the third diode is electrically connected to the third node, and the cathode of the third diode is electrically connected to the second end of the eighth resistor and the positive-phase input terminal of the comparator through the twelfth resistor.

9. The inverter power supply according to claim 7 or 8, characterized in that, The protection execution unit includes a first triode and a second triode; Wherein, the base of the first triode is electrically connected to the third node for accessing the status signal, the emitter of the first triode is grounded, the collector of the first triode is electrically connected to the base of the second triode at a fourth node, an enable signal is accessed at the fourth node, the enable signal is used to control the on / off of the second triode, the emitter of the second triode is grounded, and the collector of the second triode is used for outputting the control signal.

10. The inverter power supply according to claim 9, wherein, The converter includes a control unit, the control unit is electrically connected to the fourth node, and the control unit is used for outputting the enable signal to the fourth node.

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