Voltage discharge circuit and energy storage device

Abstract

This application relates to a voltage discharge circuit and an energy storage device. The voltage discharge circuit includes a switch circuit, a signal control circuit, and a discharge power circuit connected in sequence; the switch circuit is configured to obtain a control signal from a microcontroller unit and control the signal control circuit to output a first drive signal or a second drive signal according to the control signal; the discharge power circuit is configured to discharge the voltage of the bus capacitor when receiving the first drive signal and stop voltage discharge when receiving the second drive signal. Using this application can reduce power consumption and heat generation.

Description

Technical Field

[0001] This application relates to the technical field of voltage discharge, and particularly to a voltage discharge circuit and an energy storage device. Background Art

[0002] With the rapid development of power electronics technology, various household power supply products have emerged continuously, bringing great convenience to our lives. During the use and maintenance of household power supply products, it is necessary to ensure compliance with safety regulations to avoid electric shock accidents; therefore, it is stipulated that after the power supply product is powered off for a certain period of time, the residual voltage inside needs to be lower than the safety voltage value. For example: after power off for five minutes, the voltage of the inert components inside the power supply product needs to be lower than the safety voltage of 60V.

[0003] Currently, most power supply products adopt the scheme of continuous resistance discharge. However, this scheme has the problems of high power consumption and heat generated by the resistor. Summary of the Invention

[0004] Based on this, it is necessary to provide a voltage discharge circuit and an energy storage device, which can more accurately discharge the residual voltage and reduce the power consumption and heat generated by the resistor.

[0005] In a first aspect, this application provides a voltage discharge circuit, which includes a switch circuit, a signal control circuit, and a discharge power circuit connected in sequence;

[0006] The switch circuit is used to obtain a control signal from the microcontroller unit and control the signal control circuit to output a first drive signal or a second drive signal according to the control signal;

[0007] The discharge power circuit is used to discharge the voltage of the bus capacitor when receiving the first drive signal and stop the voltage discharge when receiving the second drive signal.

[0008] In some embodiments, the switch circuit is used to control the signal control circuit to output a first drive signal or a second drive signal according to the control signal output by the microcontroller unit and the power supply voltage of the microcontroller unit.

[0009] In some embodiments, the controlled end of the switch circuit is connected to the output end of the microcontroller unit for receiving the control signal; the first end of the switch circuit is connected to the power supply voltage of the microcontroller unit; the second end of the switch circuit is used for grounding.

[0010] In some embodiments, the switch circuit includes a resistor R1, a resistor R2, a first switch tube, and a diode;

[0011] Both ends of the resistor R1 are respectively connected to the microcontroller unit and the control electrode of the first switch tube;

[0012] The first pole of the first switching tube is connected to the first end of the resistor R2, and the second pole of the first switching tube is grounded;

[0013] The second end of the resistor R2 is connected to the cathode of the diode;

[0014] The anode of the diode is connected to the power supply voltage of the microcontroller unit.

[0015] In some embodiments, the signal control circuit is further configured to, after outputting the first driving signal, maintain the output of the first driving signal based on the voltage of the bus capacitor.

[0016] In some embodiments, the signal control circuit is further configured to, after outputting the first driving signal, maintain the output of the first driving signal based on the voltage of the bus capacitor until the voltage of the bus capacitor discharges to a preset voltage.

[0017] In some embodiments, the signal control circuit includes a first voltage stabilizing module, a second voltage stabilizing module, a first switching module, and a second switching module;

[0018] The first voltage stabilizing module is respectively connected to the bus capacitor and the first switching module;

[0019] The first switching module is respectively connected to the second switching module and the second voltage stabilizing module;

[0020] The second voltage stabilizing module is further respectively connected to the switching circuit and the second switching module;

[0021] The second switching module is further connected to the discharge power circuit.

[0022] In some embodiments, the first voltage stabilizing module includes a first voltage stabilizing diode and a resistor R3; the second voltage stabilizing module includes a second voltage stabilizing diode and a filter capacitor; the first switching module includes a second switching tube and a resistor R4; the second switching module includes a third switching tube and a resistor R5;

[0023] The negative pole of the first voltage stabilizing diode is connected to the bus capacitor, and the positive pole of the first voltage stabilizing diode is connected to the first end of the resistor R3;

[0024] The second end of the resistor R3 is connected to the first pole of the second switching tube;

[0025] The control pole of the second switching tube is connected to the first pole of the third switching tube, and the second pole of the second switching tube is connected to the negative pole of the second voltage stabilizing diode;

[0026] Both ends of the resistor R4 are respectively connected to the control pole and the first pole of the second switching tube;

[0027] The negative pole of the second voltage stabilizing diode is connected to the switching circuit, and the positive pole of the second voltage stabilizing diode is grounded;

[0028] The first end of the filtering capacitor is connected to the negative electrode of the second voltage stabilizing diode, and the second end of the filtering capacitor is grounded;

[0029] Both ends of the resistor R5 are respectively connected to the negative electrode of the second voltage stabilizing diode and the control electrode of the third switching transistor;

[0030] The first pole of the third switching transistor is also connected to the discharging power circuit, and the second pole of the third switching transistor is grounded.

[0031] In some embodiments, the discharging power circuit includes a bus capacitor, a discharging resistor, a fourth switching transistor, a resistor R6, and a resistor R7;

[0032] The first end of the bus capacitor is connected to the first end of the discharging resistor, and the other end of the bus capacitor is grounded;

[0033] The second end of the discharging resistor is connected to the first pole of the fourth switching transistor;

[0034] The control electrode of the fourth switching transistor is connected to the signal control circuit, and the second pole of the fourth switching transistor is grounded;

[0035] Both ends of the resistor R6 are respectively connected to the signal control circuit and the control electrode of the fourth switching transistor;

[0036] Both ends of the resistor R7 are respectively connected to the control electrode and the first pole of the fourth switching transistor.

[0037] In a second aspect, the present application provides an energy storage device, which includes a micro control unit and the voltage discharging circuit as described in the first aspect.

[0038] For the above voltage discharging circuit and energy storage device, the voltage discharging circuit includes a switching circuit, a signal control circuit, and a discharging power circuit connected in sequence; the switching circuit obtains a control signal from the micro control unit and controls the signal control circuit to output a first driving signal or a second driving signal according to the control signal; the discharging power circuit discharges the voltage of the bus capacitor when receiving the first driving signal and stops discharging the voltage when receiving the second driving signal. In the technical solution of the embodiment of the present application, the voltage discharging circuit discharges the voltage of the bus capacitor only after power-off. When the energy storage device is working normally, the discharging power circuit does not work, so the power consumption and heat generated by the discharging resistor can be reduced. Description of the Drawings

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0040] Figure 1 One of the schematic structural diagrams of the voltage discharge circuit according to an embodiment;

[0041] Figure 2 Another one of the schematic structural diagrams of the voltage discharge circuit according to an embodiment;

[0042] Figure 3 Another one of the schematic structural diagrams of the voltage discharge circuit according to an embodiment;

[0043] Figure 4 Another one of the schematic structural diagrams of the voltage discharge circuit according to an embodiment;

[0044] Figure 5 Another one of the schematic structural diagrams of the voltage discharge circuit according to an embodiment;

[0045] Figure 6 Another one of the schematic structural diagrams of the voltage discharge circuit according to an embodiment;

[0046] Figure 7 Schematic structural diagram of an energy storage device according to an embodiment.

[0047] Explanation of reference numerals:

[0048] Voltage discharge circuit 1, microcontroller unit 2;

[0049] Switching circuit 10, signal control circuit 20, discharge power circuit 30;

[0050] First voltage regulator module 201, second voltage regulator module 202, first switching module 203;

[0051] Second switching module 204, diode D, resistor R1, resistor R2, resistor R3, resistor R4;

[0052] Resistor R5, resistor R6, resistor R7, resistor R8;

[0053] First switching transistor Q1, second switching transistor Q2, third switching transistor Q3, third switching transistor Q4;

[0054] First voltage stabilizing diode ZD1, second voltage stabilizing diode ZD2, filter capacitor C1, bus capacitor C2. Detailed implementation manners

[0055] To facilitate the understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. Embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0056] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0057] It can be understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, the first resistor may be referred to as the second resistor, and similarly, the second resistor may be referred to as the first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0058] It can be understood that for "connection" in the following embodiments, if there is transmission of electrical signals or data between the connected circuits, modules, units, etc., it should be understood as "electrical connection", "communication connection", etc.

[0059] It can be understood that "at least one" means one or more, and "a plurality" means two or more. "At least part of an element" means part or all of the element.

[0060] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprises / include", "has" or the like specify the presence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the related listed items.

[0061] With the rapid development of power electronics technology, various household power supply products have emerged continuously, bringing great convenience to our lives. Household power supply products need to ensure compliance with safety regulations during use and maintenance to avoid electric shock accidents; therefore, it is stipulated that after the power supply product is powered off for a certain period of time, the residual voltage inside needs to be lower than the safety voltage value. For example: after powering off for five minutes, the voltage of the inert components inside the power supply product needs to be lower than 60V of the safety voltage.

[0062] Currently, most power supply products adopt the scheme of continuous resistance discharge, that is, the resistor is also in a working state even when there is no need to discharge the voltage. Therefore, this scheme has the problem of relatively high power consumption and heat generated by the resistor.

[0063] In view of the above problems, an embodiment of the present application provides a voltage discharge circuit. The voltage discharge circuit includes a switch circuit, a signal control circuit, and a discharge power circuit connected in sequence; the switch circuit obtains a control signal from a microcontroller unit, and controls the signal control circuit to output a first drive signal or a second drive signal according to the control signal; the discharge power circuit discharges the voltage of the bus capacitor when receiving the first drive signal, and stops voltage discharge when receiving the second drive signal. In the technical solution of the embodiment of the present application, the voltage discharge circuit discharges the voltage of the bus capacitor only after power-off. When the energy storage device is working normally, the discharge power circuit does not work, so the power consumption and heat generated by the discharge resistor can be reduced. The technical solution involved in the embodiment of the present application will be introduced below.

[0064] In one embodiment, as Figure 1 shown, a voltage discharge circuit is provided. The voltage discharge circuit 1 includes a switch circuit 10, a signal control circuit 20, and a discharge power circuit 30 connected in sequence; the switch circuit 10 is configured to obtain a control signal from a microcontroller unit (MCU) 2, and control the signal control circuit 20 to output a first drive signal or a second drive signal according to the control signal; the discharge power circuit 30 is configured to discharge the voltage VCC_BUS of the bus capacitor when receiving the first drive signal, and stop voltage discharge when receiving the second drive signal.

[0065] In the embodiment of the present application, the voltage discharge circuit 1 includes a switch circuit 10, a signal control circuit 20, and a discharge power circuit 30, and the switch circuit 10, the signal control circuit 20, and the discharge power circuit 30 are connected in sequence.

[0066] The switch circuit 10 can obtain a control signal from the microcontroller unit 2. For example, when the microcontroller unit 2 is controlled to power off or abnormally power off, a first control signal is obtained from the microcontroller unit 2. When the microcontroller unit 2 is working normally, a second control signal is obtained from the microcontroller unit 2. The switch circuit 10 controls the signal control circuit 20 to output a first drive signal according to the first control signal, and controls the signal control circuit 20 to output a second drive signal according to the second control signal.

[0067] The discharge power circuit 30 is connected to the signal control circuit 20 and receives the first drive signal or the second drive signal output by the signal control circuit 20. The discharge power circuit 30 includes a bus capacitor. When receiving the first drive signal, the discharge power circuit 30 discharges the voltage VCC_BUS of the bus capacitor; when receiving the second drive signal, the discharge power circuit 30 stops voltage discharge.

[0068] In the above embodiments, the voltage discharge circuit includes a switch circuit, a signal control circuit, and a discharge power circuit connected in sequence; the switch circuit obtains a control signal from the microcontroller unit and controls the signal control circuit to output a first drive signal or a second drive signal according to the control signal; the discharge power circuit discharges the voltage of the bus capacitor when receiving the first drive signal and stops discharging the voltage when receiving the second drive signal. In the technical solution of the embodiments of the present application, the voltage discharge circuit discharges the voltage of the bus capacitor only after power-off. When the energy storage device is working normally, the discharge power circuit does not work, so the power consumption and heat generated by the discharge resistor can be reduced.

[0069] In one embodiment, the switch circuit 10 is configured to control the signal control circuit 20 to output a first drive signal or a second drive signal according to a control signal output by the microcontroller unit 2 and the power supply voltage VCC_MCU of the microcontroller unit 2.

[0070] In the embodiments of the present application, the switch circuit 10 can obtain a control signal from the microcontroller unit 2, and the power supply voltage VCC_MCU of the microcontroller unit 2 can also provide a voltage for the signal control circuit 20.

[0071] Exemplarily, when the microcontroller unit 2 receives a power-off instruction, it outputs a first control signal to the switch circuit 10. The switch circuit 10 obtains the first control signal and controls the signal control circuit 20 to output a first drive signal based on the power supply voltage VCC_MCU of the microcontroller unit 2, so that the discharge power circuit 30 discharges the voltage VCC_BUS of the bus capacitor according to the first drive signal, that is, voltage discharge can be achieved under controlled power-off.

[0072] For the case of sudden power-off, the microcontroller unit 2 does not receive a valid power-off instruction, but the power supply voltage VCC_MCU of the microcontroller unit 2 has not dropped yet and can still reach the reset voltage. Then, the second control signal obtained by the switch circuit 10 from the microcontroller unit 2. After that, the power supply voltage VCC_MCU of the microcontroller unit 2 gradually drops to the reset voltage and the microcontroller unit 2 stops working. Then, the first control signal obtained by the switch circuit 10 from the microcontroller unit 2, and the switch circuit 10 controls the signal control circuit 20 to output a first drive signal based on the power supply voltage VCC_MCU of the microcontroller unit 2, so that the discharge power circuit 30 discharges the voltage VCC_BUS of the bus capacitor according to the first drive signal, that is, voltage discharge can also be achieved in the case of sudden power-off.

[0073] In some embodiments, the common voltage of the power supply voltage VCC_MCU of the microcontroller unit 2 can be 5V or 3.3V, and the reset voltage can be 2.8V.

[0074] In the above embodiments, the switch circuit controls the signal control circuit to output a first driving signal or a second driving signal according to the control signal output by the microcontroller unit and the power supply voltage of the microcontroller unit. In the technical solution of the embodiments of the present application, the switch circuit is controlled based on the control signal and the power supply voltage of the microcontroller unit, and can enable the signal control circuit to output a first driving signal both in the case of normal power-down and abnormal sudden power-down of the microcontroller unit, so as to reliably provide an effective discharge signal.

[0075] In one embodiment, as Figure 2 shown, the controlled end of the switch circuit 10 is connected to the output terminal P_EN of the microcontroller unit 2 for receiving a control signal; the first end of the switch circuit 10 is connected to the power supply voltage VCC_MCU of the microcontroller unit 2; the second end of the switch circuit 10 is used for grounding GND.

[0076] In the embodiments of the present application, the controlled end of the switch circuit 10 is connected to the output terminal P_EN of the microcontroller unit 2, and the control signal output by the microcontroller unit 2 can be input into the switch circuit 10 through this controlled end. The first end of the switch circuit 10 is connected to the power supply voltage VCC_MCU of the microcontroller unit 2. In this way, in the case of receiving a power-down instruction, the signal control circuit 20 can be controlled to output a first driving signal according to the obtained first control signal and the power supply voltage VCC_MCU of the microcontroller unit 2; or, in the case of sudden power-down, the signal control circuit 20 can be controlled to output a first driving signal according to the obtained first control signal and the power supply voltage VCC_MCU of the microcontroller unit 2.

[0077] In the above embodiments, the controlled end of the switch circuit receives a control signal; the first end of the switch circuit is connected to the power supply voltage of the microcontroller unit; the second end of the switch circuit is grounded. In the technical solution of the embodiments of the present application, through the above connection method, the switch circuit can be controlled by using the output terminal signal and the power supply voltage of the microcontroller unit, so that the signal control circuit can reliably provide an effective discharge signal.

[0078] In one embodiment, as Figure 3 shown, the switch circuit 10 includes a resistor R1, a resistor R2, a first switching transistor Q1, and a diode D; both ends of the resistor R1 are respectively connected to the microcontroller unit 2 and the control electrode of the first switching transistor Q1; the first pole of the first switching transistor Q1 is connected to the first end of the resistor R2, and the second pole of the first switching transistor Q1 is grounded GND; the second end of the resistor R2 is connected to the cathode of the diode D; the anode of the diode D is connected to the power supply voltage VCC_MCU of the microcontroller unit 2.

[0079] In the embodiment of the present application, the switching circuit 10 includes a resistor R1, a resistor R2, a first switching transistor Q1, and a diode D. Taking the first switching transistor Q1 as an NPN transistor as an example, two ends of the resistor R1 are respectively connected to an output terminal P_EN of the microcontroller unit 2 and a base of the first switching transistor Q1; a collector of the first switching transistor Q1 is connected to a first end of the resistor R2, an emitter of the first switching transistor Q1 is grounded to GND; a second end of the resistor R2 is connected to a cathode of the diode D; an anode of the diode D is connected to a power supply voltage VCC_MCU of the microcontroller unit 2.

[0080] It should be noted that the first switching transistor Q1 is not limited to the above-mentioned NPN transistor, and may also be a MOS (Metal Oxide Semiconductor) transistor or other transistors, which can be set according to actual situations.

[0081] When the microcontroller unit 2 is under controlled power-on or sudden power-off, a first control signal output by the output terminal P_EN may be a low level. In this way, the first switching transistor Q1 is turned off, and the power supply voltage VCC_MCU of the microcontroller unit 2 outputs a high level to the signal control circuit 20 through the diode D and the resistor R2, and the signal control circuit 20 outputs a first drive signal.

[0082] When the microcontroller unit 2 is operating normally, a second control signal output by the output terminal P_EN may be a high level. In this way, the first switching transistor Q1 is turned on, the switching circuit 10 outputs a low level to the signal control circuit 20, and the signal control circuit 20 outputs a second drive signal.

[0083] The resistor R2 is a current-limiting resistor, which can limit the magnitude of the current input to the control electrode of the first switching transistor Q1.

[0084] Functions of the diode D include: preventing the voltage at the controlled end of the switching circuit 10 from flowing back to the power supply voltage VCC_MCU of the microcontroller unit 2 and burning relevant devices.

[0085] In the above embodiment, the switching circuit includes a resistor R1, a resistor R2, a first switching transistor, and a diode; two ends of the resistor R1 are respectively connected to the microcontroller unit and the control electrode of the first switching transistor; a first pole of the first switching transistor is connected to a first end of the resistor R2, a second pole of the first switching transistor is grounded; a second end of the resistor R2 is connected to a cathode of the diode; an anode of the diode is connected to the power supply voltage of the microcontroller unit. In the technical solution of the embodiment of the present application, by controlling the on / off of the first switching transistor to control the subsequent signal control circuit to output corresponding drive signals, the circuit structure is simple and easy to implement, and is stable and reliable.

[0086] In one embodiment, the signal control circuit 20 is further configured to, after outputting the first drive signal, maintain the output of the first drive signal based on the voltage VCC_BUS of the bus capacitor.

[0087] In the embodiment of the present application, after the signal control circuit 20 outputs the first driving signal, the discharging power circuit 30 discharges the voltage VCC_BUS of the bus capacitor according to the first driving signal. In order to maintain the voltage discharge, the signal control circuit 20 needs to continuously output the first driving signal.

[0088] Based on the above considerations, the signal control circuit 20 is connected to the bus capacitor. In this way, the voltage VCC_BUS of the bus capacitor maintains the operation of the signal control circuit 20, enabling the signal control circuit 20 to maintain the output of the first driving signal.

[0089] In the above embodiment, after the signal control circuit outputs the first driving signal, the output of the first driving signal is maintained based on the voltage of the bus capacitor. Since when the power supply product (such as an energy storage device) is powered off, the microcontroller unit will also be powered off after a period of time, that is, the microcontroller unit does not continuously output control signals, and the signal control circuit does not continuously drive the discharging power circuit to work based on the first driving signal output by the switching circuit. In the technical solution of the embodiment of the present application, after the switching circuit 20 drives the signal control circuit to output the first driving signal, the voltage VCC_BUS of the bus capacitor maintains the output of the first driving signal by the signal control circuit, that is, the voltage VCC_BUS of the bus capacitor takes over the control of the signal control circuit 20 to output the first driving signal, so that the discharging power circuit can still work even if the microcontroller unit continuously outputs control signals. In addition, the signal control circuit does not need to be connected to other power supplies, thus simplifying the circuit connection and saving space.

[0090] Further, in the case where the microcontroller unit 2 is controlled to power off or powers off abnormally, the voltage of the bus capacitor has not been discharged to the preset voltage, but the energy storage device suddenly gets powered on. At this time, after the microcontroller unit 2 returns to normal, the switching circuit 10 obtains the second control signal from the microcontroller unit 2 and controls the driving signal control circuit 20 to output the second driving signal, so as to control the discharging power circuit to stop discharging continuously. In one embodiment, the signal control circuit 20 is further configured to, after outputting the first driving signal, maintain the output of the first driving signal based on the voltage VCC_BUS of the bus capacitor until the voltage VCC_BUS of the bus capacitor is discharged to the preset voltage.

[0091] In the embodiments of the present application, the voltage VCC_BUS of the bus capacitor does not need to be completely discharged, that is, it is not necessary to discharge the voltage VCC_BUS of the bus capacitor to 0V. Discharging the voltage VCC_BUS of the bus capacitor to a preset voltage can meet the safety requirements. Based on this consideration, the signal control circuit 20 can be correspondingly set. In this way, when the voltage VCC_BUS of the bus capacitor is not discharged to the preset voltage, the signal control circuit 20 continuously maintains the output of the first driving signal, so that the discharge power circuit 30 continuously discharges the voltage VCC_BUS of the bus capacitor. When the voltage VCC_BUS of the bus capacitor is discharged to the preset voltage, the signal control circuit 20 stops outputting the first driving signal, that is, the signal control circuit 20 outputs a second driving signal to make the discharge power circuit 30 stop discharging the voltage.

[0092] In the above embodiments, the signal control circuit is further configured to maintain the output of the first driving signal based on the voltage of the bus capacitor after outputting the first driving signal until the voltage of the bus capacitor is discharged to the preset voltage. In the technical solution of the embodiments of the present application, it is not necessary to completely discharge the voltage of the bus capacitor. Discharging the voltage of the bus capacitor to the preset voltage can meet the safety requirements, shorten the discharge time, improve the discharge efficiency, and thus reduce the power consumption and heat generation.

[0093] In one embodiment, as Figure 4 shown, the signal control circuit 20 includes a first voltage stabilizing module 201, a second voltage stabilizing module 202, a first switch module 203, and a second switch module 204; the first voltage stabilizing module 201 is respectively connected to the bus capacitor and the first switch module 203; the first switch module 203 is respectively connected to the second switch module 204 and the second voltage stabilizing module 202; the second voltage stabilizing module 202 is further respectively connected to the switch circuit 10 and the second switch module 204; the second switch module 204 is further connected to the discharge power circuit 30.

[0094] In the embodiments of the present application, the signal control circuit 20 includes a first voltage stabilizing module 201, a second voltage stabilizing module 202, a first switch module 203, and a second switch module 204; the first voltage stabilizing module 201 is respectively connected to the voltage VCC_BUS of the bus capacitor and the first switch module 203; the first switch module 203 is respectively connected to the second switch module 204 and the second voltage stabilizing module 202; the second voltage stabilizing module 202 is further respectively connected to the switch circuit 10 and the second switch module 204; the second switch module 204 is further connected to the discharge power circuit 30. The first switch module 203, the second switch module 204, and the second voltage stabilizing module 202 are all connected to the switch circuit 10.

[0095] Based on the description in the above embodiments, after receiving the first control signal, the switch circuit 10 controls the second switch module 204 to output a first driving signal according to the first control signal. After receiving the first driving signal, the discharge power circuit 30 discharges the voltage VCC_BUS of the bus capacitor. After receiving the first control signal, the second switch module 204 will connect the first switch module 203 to the first voltage stabilizing module 201 and the second voltage stabilizing module 202, forming a path from the voltage VCC_BUS of the bus capacitor to the first voltage stabilizing module 201, the first switch module 203, and the second voltage stabilizing module 202.

[0096] After the voltage VCC_BUS of the bus capacitor is discharged, it gradually decreases. After the voltage VCC_BUS of the bus capacitor drops to a preset voltage, the first voltage stabilizing module 201 cuts off the connection between the voltage VCC_BUS of the bus capacitor and the first switch module 203. In this way, the path from the first voltage stabilizing module 201 to the first switch module 203 and the second voltage stabilizing module 202 is cut off, and then the second switch module 204 outputs a second driving signal. The discharge power circuit 30 receives the second driving signal and stops discharging the voltage.

[0097] In the above embodiments, the signal control circuit includes a first voltage stabilizing module, a second voltage stabilizing module, a first switch module, and a second switch module; the first voltage stabilizing module is respectively connected to the bus capacitor and the first switch module; the first switch module is respectively connected to the second switch module and the second voltage stabilizing module; the second voltage stabilizing module is also respectively connected to the switch circuit and the second switch module; the second switch module is also connected to the discharge power circuit. In the technical solution of the embodiment of the present application, the first voltage stabilizing module, the second voltage stabilizing module, the first switch module, and the second switch module cooperate with each other, can reliably output the first driving signal and maintain the output of the first driving signal, so as to more accurately discharge the residual voltage and reduce the power consumption and heat generated by the resistor.

[0098] In one embodiment, as Figure 5As shown in the figure, the first voltage stabilizing module 201 includes a first voltage stabilizing diode ZD1 and a resistor R3; the second voltage stabilizing module 202 includes a second voltage stabilizing diode ZD2 and a filtering capacitor C1; the first switching module 203 includes a second switching transistor Q2 and a resistor R4; the second switching module 204 includes a third switching transistor Q3 and a resistor R5; the negative electrode of the first voltage stabilizing diode ZD1 is connected to the bus capacitor, and the positive electrode of the first voltage stabilizing diode ZD1 is connected to the first end of the resistor R3; the second end of the resistor R3 is connected to the first pole of the second switching transistor Q2; the control pole of the second switching transistor Q2 is connected to the first pole of the third switching transistor Q3, and the second pole of the second switching transistor Q2 is connected to the negative electrode of the second voltage stabilizing diode ZD2; the two ends of the resistor R4 are respectively connected to the control pole and the first pole of the second switching transistor Q2; the negative electrode of the second voltage stabilizing diode ZD2 is connected to the switching circuit 10, and the positive electrode of the second voltage stabilizing diode ZD2 is grounded to GND; the first end of the filtering capacitor C1 is connected to the negative electrode of the second voltage stabilizing diode ZD2, and the second end of the filtering capacitor C1 is grounded to GND; the two ends of the resistor R5 are respectively connected to the negative electrode of the second voltage stabilizing diode ZD2 and the control pole of the third switching transistor Q3; the first pole of the third switching transistor Q3 is further connected to the discharge power circuit 30, and the second pole of the third switching transistor Q3 is grounded to GND.

[0099] In the embodiment of the present application, taking the first switching transistor Q1 and the third switching transistor Q3 as NPN transistors and the second switching transistor Q2 as a PNP transistor as an example, when the microcontroller unit 2 is powered on or powered off abnormally, the first control signal obtained from the microcontroller unit 2 is at a low level, the first switching transistor Q1 is turned off, and the power supply voltage VCC_MCU of the microcontroller unit 2 is poured into the control pole of the third switching transistor Q3 through the diode D, the resistor R2, and the resistor R5, so that the third switching transistor Q3 is turned on, and the driving ability of the first control signal is enhanced. After the third switching transistor Q3 is turned on, a first driving signal at a low level is output to the discharge power circuit 30.

[0100] When the third switching transistor Q3 is turned on, the control pole of the second switching transistor Q2 is connected to a low level, and the second switching transistor Q2 is turned on, forming a path from the bus capacitor, the first voltage stabilizing diode ZD1, the resistor R3, the second switching transistor Q2, the second voltage stabilizing diode ZD2 to the ground GND. The second voltage stabilizing diode ZD2 plays a clamping role, and the voltage of the bus capacitor is transmitted to the control pole of the third switching transistor Q3 through the first voltage stabilizing diode ZD1, the resistor R3, and the second switching transistor Q2, maintaining the conduction of the third switching transistor Q3, and thus maintaining the first driving signal at a low level output by the third switching transistor Q3.

[0101] During the process of the bus capacitor continuously discharging voltage, when the voltage VCC_BUS of the bus capacitor drops to a preset voltage, the first voltage regulator ZD1 will no longer break down, and the first voltage regulator ZD1 cuts off the connection from the bus capacitor to the second switching transistor Q2. The path of the first voltage regulator ZD1, resistor R3, second switching transistor Q2, and second voltage regulator ZD2 is cut off, and the third switching transistor Q3 is turned off and outputs a high-level second drive signal. The discharge power circuit 30 receives the second drive signal and stops discharging voltage.

[0102] Moreover, the second voltage regulator ZD2 plays a clamping role and can also prevent the control signal from being over-injected and burning out the current-limiting resistor R5 and the components in the signal control circuit 20 when the voltage VCC_BUS of the bus capacitor is relatively high and the second switching transistor Q2 is turned on.

[0103] The resistor R5 is a current-limiting resistor and is connected to the control electrode of the third switching transistor Q3, which can limit the control electrode current of the third switching transistor Q3.

[0104] The resistor R4 is a pull-up resistor, which provides a voltage difference between the control electrode and the first electrode of the second switching transistor Q2 to turn on the second switching transistor Q2; and ensures that when the third switching transistor Q3 is turned off, the second switching transistor Q2 is also turned off.

[0105] The filter capacitor C1 can filter out interference signals and prevent the thyristor from being mis-triggered.

[0106] It should be noted that the second switching transistor Q2 and the third switching transistor Q3 are not limited to triodes, and MOS transistors or other transistors can also be used.

[0107] In the above embodiment, the first voltage regulation module includes a first voltage regulator and a resistor R3; the second voltage regulation module includes a second voltage regulator and a filter capacitor; the first switching module includes a second switching transistor and a resistor R4; the second switching module includes a third switching transistor and a resistor R5. In the technical solution of the embodiment of the present application, an effective discharge signal can be reliably output through the third switching transistor. The conduction and cut-off of the path between the first voltage regulator and the second voltage regulator can be controlled through the second switching transistor to maintain the operation of the third switching transistor and the continuous output of the discharge signal. The voltage of the bus capacitor can be discharged to a preset voltage through the first voltage regulator, thereby controlling the discharge time and improving the discharge efficiency. The above components cooperate with each other to improve the stability and reliability of the discharge circuit, so as to better achieve voltage discharge.

[0108] In one embodiment, as Figure 6As shown in the figure, the discharge power circuit 30 includes a bus capacitor C2, a discharge resistor R8, a fourth switching transistor Q4, a resistor R6, and a resistor R7. The first terminal of the bus capacitor C2 is connected to the first terminal of the discharge resistor R8, and the other terminal of the bus capacitor C2 is grounded to GND. The second terminal of the discharge resistor R8 is connected to the first pole of the fourth switching transistor Q4. The control pole of the fourth switching transistor Q4 is connected to the signal control circuit 20, and the second pole of the fourth switching transistor Q4 is grounded to GND. The two ends of the resistor R6 are respectively connected to the signal control circuit 20 and the control pole of the fourth switching transistor Q4. The two ends of the resistor R7 are respectively connected to the control pole and the first pole of the fourth switching transistor Q4.

[0109] In the embodiment of the present application, taking the fourth switching transistor Q4 as a PNP transistor as an example, when the third switching transistor Q3 is turned on, a current path is formed at the control pole of the fourth switching transistor Q4, so that the fourth switching transistor Q4 is turned on, and then a path from the bus capacitor C2 to the discharge resistor R8, the fourth switching transistor Q4, and the ground GND is formed, thereby discharging the voltage VCC_BUS of the bus capacitor.

[0110] When the third switching transistor Q3 is turned off, a current path is not formed at the control pole of the fourth switching transistor Q4, and the fourth switching transistor Q4 is turned off, cutting off the path from the bus capacitor C2 to the discharge resistor R8, the fourth switching transistor Q4, and the ground GND, thereby stopping the voltage discharge.

[0111] The resistor R8 is a discharge resistor, and an appropriate resistance value and resistor power can be selected according to the capacitance of the aluminum electrolytic capacitor.

[0112] The resistor R6 is a current-limiting resistor, which is connected to the control pole of the fourth switching transistor Q4 and can limit the control pole current of the fourth switching transistor.

[0113] The resistor R7 is a pull-up resistor, which can ensure that when the third switching transistor Q3 is turned off, the fourth switching transistor Q4 is also turned off.

[0114] It can be understood that the selection of the first zener diode ZD1 can determine the preset voltage of the voltage discharge; the selection of the resistor R8 can determine the discharge time according to the preset voltage, so as to more accurately achieve the discharge of the residual voltage; and make the residual voltage of the inert components in the energy storage device better adapt to different safety regulation voltages. In addition, the selection of the discharge resistor can achieve a smaller package. During the normal working time of the energy storage device, the discharge resistor does not work and does not dissipate power, and the heat generation of the whole machine is lower, which is beneficial to the thermal design.

[0115] In the above embodiment, the discharge power circuit includes a bus capacitor, a discharge resistor, a fourth switching transistor, a resistor R6, and a resistor R7. The technical solution of the embodiment of the present application controls the on-off of the discharge path by controlling the fourth switching transistor, so that the discharge resistor does not work when there is no need to discharge the voltage, thereby reducing the power consumption and heat generated by the resistor.

[0116] In one embodiment, as Figure 7 shown, an energy storage device is provided. The energy storage device includes a micro control unit 2 and the voltage discharge circuit 1 in the above embodiment.

[0117] In the embodiment of the present application, by adopting the above voltage discharge circuit, the energy storage device can more accurately discharge the residual voltage, so that the energy storage device can obtain a longer battery life; and the residual voltage of the inert components in the energy storage device can better adapt to different safety regulated voltages. In addition, the selection of the discharge resistor can achieve a smaller package. During the normal working time of the energy storage device, the discharge resistor does not work and does not dissipate power, and the heat generation of the whole machine is lower, which is beneficial to thermal design.

[0118] In the description of this specification, the descriptions referring to the terms "some embodiments", "other embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0119] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0120] The above-described embodiments only represent several implementation manners of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the present application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A voltage discharge circuit, characterized in that: The voltage discharge circuit comprises a switch circuit, a signal control circuit and a discharge power circuit connected in sequence; The switch circuit is used to obtain a control signal from the micro control unit, and control the signal control circuit to output the first drive signal or the second drive signal according to the control signal; The discharge power circuit is used to discharge the voltage of the bus capacitor when receiving the first drive signal, and stop voltage discharge when receiving the second drive signal; The switch circuit is specifically used to control the signal control circuit to output the first drive signal according to the control signal output by the micro control unit and the power supply voltage of the micro control unit when the micro control unit is powered off normally or suddenly; Wherein, the signal control circuit includes a first voltage stabilizing module, a second voltage stabilizing module, a first switch module and a second switch module; The first voltage stabilizing module is connected to the bus capacitor and the first switch module respectively; The first switch module is connected to the second switch module and the second voltage stabilizing module respectively; The second voltage stabilizing module is also connected to the switch circuit and the second switch module respectively; The second switch module is also connected to the discharge power circuit; The discharge power circuit discharges the voltage of the bus capacitor after receiving the first drive signal; after the voltage of the bus capacitor is discharged to a preset voltage, the first voltage stabilizing module cuts off the connection between the voltage of the bus capacitor and the first switch module, and the second switch module outputs the second drive signal; the discharge power circuit receives the second drive signal and stops voltage discharge; The first voltage stabilizing module includes a first voltage stabilizing tube and a resistor R3; the second voltage stabilizing module includes a second voltage stabilizing tube and a filter capacitor; the first switch module includes a second switch tube and a resistor R4; the second switch module includes a third switch tube and a resistor R5; The cathode of the first voltage regulator tube is connected to the bus capacitor, and the anode of the first voltage regulator tube is connected to the first end of the resistor R3; The second end of the resistor R3 is connected to the first electrode of the second switch tube; The control electrode of the second switch tube is connected to the first electrode of the third switch tube, and the second electrode of the second switch tube is connected to the negative electrode of the second voltage regulator tube; The two ends of the resistor R4 are respectively connected to the control electrode and the first electrode of the second switch tube; The cathode of the second voltage regulator tube is connected to the switch circuit, and the anode of the second voltage regulator tube is grounded; The first end of the filter capacitor is connected to the negative electrode of the second voltage regulator tube, and the second end of the filter capacitor is grounded; The two ends of the resistor R5 are respectively connected to the negative electrode of the second voltage regulator tube and the control electrode of the third switch tube; The first electrode of the third switch tube is also connected to the discharge power circuit, and the second electrode of the third switch tube is grounded.

2. The voltage discharge circuit according to claim 1, characterized in that: The controlled end of the switch circuit is connected to the output end of the micro control unit for receiving the control signal; the first end of the switch circuit is connected to the power supply voltage of the micro control unit; and the second end of the switch circuit is grounded.

3. The voltage discharge circuit according to claim 2, characterized in that: The switch circuit includes a resistor R1, a resistor R2, a first switch tube and a diode; The two ends of the resistor R1 are respectively connected to the micro control unit and the control electrode of the first switch tube; The first electrode of the first switch tube is connected to the first end of the resistor R2, and the second electrode of the first switch tube is grounded; The second end of the resistor R2 is connected to the cathode of the diode; The anode of the diode is connected to the power supply voltage of the micro control unit.

4. The voltage discharge circuit according to any one of claims 1 to 3, characterized in that: The signal control circuit is further configured to maintain the output of the first drive signal based on the voltage of the bus capacitor after outputting the first drive signal.

5. The voltage discharge circuit according to claim 4, characterized in that: The signal control circuit is further configured to maintain the output of the first drive signal based on the voltage of the bus capacitor after outputting the first drive signal, until the voltage of the bus capacitor is discharged to a preset voltage.

6. The voltage discharge circuit according to claim 4, characterized in that: The power discharge circuit includes a bus capacitor, a discharge resistor, a fourth switch tube, a resistor R6 and a resistor R7; A first end of the bus capacitor is connected to a first end of the discharge resistor, and the other end of the bus capacitor is grounded; The second end of the discharge resistor is connected to the first electrode of the fourth switch tube; The control electrode of the fourth switch tube is connected to the signal control circuit, and the second electrode of the fourth switch tube is grounded; The two ends of the resistor R6 are respectively connected to the signal control circuit and the control electrode of the fourth switch tube; Two ends of the resistor R7 are connected to the control electrode and the first electrode of the fourth switch tube respectively.

7. An energy storage device, characterized in that: The energy storage device comprises a micro control unit and a voltage discharge circuit as described in any one of claims 1 to 6.

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