Protection circuit of bootstrap power supply and energy storage power supply

Abstract

The embodiment of the utility model discloses a protection circuit of a bootstrap power supply and an energy storage power supply. The protection circuit comprises a bootstrap module; the electric energy input end of the bootstrap module is connected with a first power supply, and the signal input end of the bootstrap module is connected with a driving signal source; an under-voltage protection module; the input end of the under-voltage protection module is connected with the output end of the bootstrap module; a switch module; the input end of the switch module is connected with the output end of the under-voltage protection module, and the output end of the switch module is connected with the post-stage module; under the control of a driving signal output by the driving signal source, the first power supply provides electric energy for a capacitor in the bootstrap module, so that the bootstrap module outputs a second voltage; when the second voltage is larger than the driving voltage threshold value, the under-voltage protection module controls the switch module to be switched on so as to output the driving voltage. According to the utility model, the undervoltage protection module and the switch module are arranged, and the undervoltage protection module controls the switch module to limit the output lower limit of the driving voltage, so that undervoltage of the high-side switch module is avoided. And the reliability of the bootstrap power supply is improved.

Description

Technical Field

[0001] The embodiment of the utility model relates to the field of electronic technology, and in particular to a protection circuit of a bootstrap power supply and an energy storage power supply. Background Art

[0002] As the number of RV owners increases, the application demands for batteries become more diverse. People who often engage in outdoor activities are no longer satisfied with simply charging RV batteries with chargers. They also want to use chargers to power electrical appliances, rather than charging the batteries first and then drawing power from the batteries to power the batteries. This ensures that users can use electrical appliances in a timely manner during long-distance travel.

[0003] In the past, traditional chargers would bring a series of problems when supplying power to electrical appliances. For example, when the bootstrap capacitor in the bootstrap power supply is discharged, a voltage drop may occur, that is, voltage fluctuation will occur. The voltage fluctuation will be transmitted to the high-side MOS tube, causing the gate drive voltage of the high-side MOS tube to oscillate, resulting in insufficient drive voltage of the high-side MOS tube, which in turn affects the switching characteristics and reliability of the high-side MOS tube. Utility Model Content

[0004] The main technical problem solved by the embodiments of the utility model is to provide a bootstrap power supply protection circuit and energy storage power supply, which can prevent the high-side MOS tube driving voltage from being insufficient, and the safety hazards caused by mistakenly connecting the battery to the charger and reverse polarity due to improper user operation, thereby improving the safety and reliability of the charger.

[0005] In order to solve the above technical problems, a technical solution adopted by the utility model is: to provide a protection circuit of a bootstrap power supply, including: a bootstrap module; the power input end of the bootstrap module is connected to a first power supply, and the signal input end of the bootstrap module is connected to a driving signal source; an undervoltage protection module; the input end of the undervoltage protection module is connected to the output end of the bootstrap module; a switch module; the input end of the switch module is connected to the output end of the undervoltage protection module, and the output end of the switch module is connected to a subsequent module; under the control of the driving signal output by the driving signal source, the first power supply provides power to the capacitor in the bootstrap module so that the bootstrap module outputs a second voltage; when and only when the second voltage is greater than the driving voltage threshold, the undervoltage protection module controls the switch module to be turned on to output the driving voltage.

[0006] In some embodiments, the circuit also includes: a polarity protection module; a first input end of the polarity protection module is connected to the positive output end of the subsequent module, a second input end of the polarity protection module is connected to the negative output end of the subsequent module, a first output end of the polarity protection module is connected to the first signal end of the switch module, and a second output end of the polarity protection module is connected to the second signal end of the switch module; when the second input end of the polarity protection module receives a positive voltage, the first signal end and the second signal end of the polarity protection module are turned on to turn off the switch module.

[0007] In some embodiments, the output end of the switch module includes a first output end and a second output end, and the driving voltage includes a first driving voltage and a second driving voltage; the first output end of the switch module is connected to the first input end of the subsequent module, and the second output end of the switch module is connected to the second input end of the subsequent module; when and only when the second voltage is greater than the driving voltage threshold, the undervoltage protection module controls the switch module to turn on, so as to output the first driving voltage and the second driving voltage from the first output end of the switch module and the second output end of the switch module, respectively.

[0008] In some embodiments, the switch module includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a switch tube Q1, a switch tube Q2 and a diode D1; the emitter of the switch tube Q1 is connected to the output end of the bootstrap module and the input end of the undervoltage protection module, the collector of the switch tube Q1 is connected to the first end of the resistor R1 and the second end of the resistor R3, the second end of the resistor R1 is connected to the first end of the resistor R5, as the second output end of the switch module, outputting the second driving voltage; the second end of the resistor R3 is connected to the first end of the resistor R4 , as the first output end of the switch module, outputting the first driving voltage; the second end of the resistor R5 and the second end of the resistor R4 are connected to the anode of the diode D1, serving as the third output end of the undervoltage protection module; the base of the switch tube Q1 is connected to the first end of the resistor R2, the second end of the resistor R2 is connected to the drain of the switch tube Q2, the gate of the switch tube Q2 serves as the first signal end of the switch module, connected to the output end of the undervoltage protection module; the source of the switch tube Q2 is connected to the cathode of the diode D1, serving as the second signal end of the switch module.

[0009] In some embodiments, the undervoltage protection module includes a resistor R6, a resistor R7 and a Zener diode DZ1; wherein the cathode of the Zener diode DZ1 is connected to the output end of the bootstrap module and the input end of the switch module, the anode of the Zener diode DZ1 is connected to the first end of the resistor R6, the second end of the resistor R6 serves as the output end of the undervoltage protection module, and is connected to the first end of the resistor R7 and the first signal end of the switch module; the second end of the resistor R7 is connected to the second signal end of the switch module and the negative power supply end of the bootstrap module.

[0010] In some embodiments, the polarity protection module includes a resistor R10, a resistor R11, a resistor R12, an optocoupler U1 and a diode D2; wherein the anode of the diode D2 is connected to the negative output end of the subsequent module, the cathode of the diode D2 is connected to the first end of the resistor R10, the second end of the resistor R10 is connected to the first end of the resistor R11 and the diode anode of the optocoupler U1, the second end of the resistor R11 is connected to the first end of the resistor R12 and the diode cathode of the optocoupler U1, the second end of the resistor R12 is connected to the positive output end of the subsequent module, the transistor collector of the optocoupler U1 is connected to the first signal end of the switch module, and the transistor emitter of the optocoupler U1 is connected to the second signal end of the switch module.

[0011] In some embodiments, the bootstrap module includes a resistor R13, a resistor R14, a resistor R15, a resistor R16, a diode D3, a diode D4, a capacitor C3, a capacitor C4, a switch tube Q5, a switch tube Q6 and a switch tube Q7; wherein the anode of the diode D3 is connected to the first power supply, the cathode of the diode D3 is connected to the anode of the diode D4 and the first end of the capacitor C3, the second end of the capacitor C3 is connected to the emitter of the switch tube Q5 and the emitter of the switch tube Q6, and the cathode of the diode D4 is connected to the first end of the capacitor C4 and the first end of the resistor R13, as the bootstrap The output end of the module; the second end of the capacitor C4 is connected to the collector of the switch tube Q5 as the negative power supply end of the bootstrap module, the base of the switch tube Q5 is connected to the base of the switch tube Q6, the second end of the resistor R13, the first end of the resistor R14 and the collector of the switch tube Q7, the base of the switch tube Q7 is connected to the first end of the resistor R15 and the first end of the resistor R16, the second end of the resistor R15 is connected to the drive signal source, the second end of the resistor R16, the emitter of the switch tube Q7, the second end of the resistor R14 and the collector of the switch tube Q6 are connected to the reference ground.

[0012] In order to solve the above technical problems, another technical solution adopted by the utility model is: to provide an energy storage power supply, including: a post-stage module; the protection circuit of the bootstrap power supply as described above; the power input end of the post-stage module is connected to the first power supply, and the signal end of the post-stage module is connected to the output end of the switch module of the protection circuit of the bootstrap power supply; in response to the driving voltage output by the switch module, the post-stage module outputs a supply voltage according to the first voltage input by the first power supply.

[0013] In some embodiments, the post-stage module includes: a high-side switch module; the power input end of the high-side switch module is connected to the first power supply, the first signal end of the high-side switch module is connected to the first output end of the undervoltage protection module, the second signal end of the high-side switch module is connected to the second output end of the undervoltage protection module, and the third signal end of the high-side switch module is connected to the third output end of the undervoltage protection module; in response to the first driving voltage or the second driving voltage output by the switch module, the high-side switch module outputs the supply voltage according to the above.

[0014] In some embodiments, the high-side switch module includes a resistor R8, a resistor R9, a capacitor C1, a capacitor C2, a switch tube Q3 and a switch tube Q4; wherein, a first end of the resistor R8 is connected to the first power supply and the drain of the switch tube Q3, a second end of the resistor R8 is connected to the first end of the capacitor C1, and a second end of the capacitor C1 is connected to the first end of the resistor R9, a source of the switch tube Q3, a source of the switch tube Q4 and a third output end of the switch module; a second end of the resistor R9 is connected to the first end of the capacitor C2, a second end of the capacitor C2 is connected to the drain of the switch tube Q4, a gate of the switch tube Q3 is connected to the first output end of the switch module, a gate of the switch tube Q4 is connected to the second output end of the switch module, a drain of the switch tube Q4 serves as a positive output end of the high-side switch module, and a ground end of the high-side switch module serves as a negative output end.

[0015] The beneficial effects of the embodiment of the utility model are as follows: Different from the prior art, the embodiment of the utility model sets an undervoltage protection module and a switch module between the bootstrap module and the high-side switch module, and limits the output lower limit of the driving voltage by controlling the switch module to be turned on and off by the undervoltage protection module, thereby avoiding the high-side switch module from having an undervoltage situation; further, a polarity protection module is set, and when it is detected that the battery is connected and the polarity is reversed, the switch module is controlled to be disconnected, thereby preventing the safety hazard caused by the reverse connection of the battery. The safety and reliability of the bootstrap power supply are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the circuit diagram of the bootstrap power supply;

[0017] Figure 2 It is a structural schematic diagram of a protection circuit of a bootstrap power supply provided by an embodiment of the utility model;

[0018] Figure 3 It is a structural schematic diagram of another bootstrap power supply protection circuit provided by an embodiment of the utility model;

[0019] Figure 4 It is a circuit structure diagram of a bootstrap power supply protection circuit provided by an embodiment of the utility model;

[0020] Figure 5 This is a circuit structure diagram of a polarity protection module provided in an embodiment of the utility model;

[0021] Figure 6 This is a schematic diagram of the structure of the first energy storage power supply provided by the embodiment of the utility model;

[0022] Figure 7 It is a structural schematic diagram of a second energy storage power supply provided by an embodiment of the utility model;

[0023] Figure 8 It is a structural schematic diagram of a third energy storage power supply provided by an embodiment of the utility model;

[0024] Fig. 9 This is a circuit structure diagram of a high-side switch module provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0025] In order to facilitate the understanding of the utility model, the utility model is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this specification are for illustrative purposes only.

[0026] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by technicians in the technical field of the present invention. The terms used in this specification are only for the purpose of describing specific embodiments and are not used to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0027] See also Figure 1 , Figure 1The circuit structure of a common bootstrap power supply is shown, and the bootstrap power supply includes a resistor R13, a resistor R14, a resistor R15, a resistor R16, a diode D3, a diode D4, a capacitor C3, a capacitor C4, a switch tube Q5, a switch tube Q6 and a switch tube Q7;

[0028] The anode of the diode D3 is connected to the first power supply VS, the cathode of the diode D3 is connected to the anode of the diode D4 and the first end of the capacitor C3, the second end of the capacitor C3 is connected to the emitter of the switch tube Q5 and the emitter of the switch tube Q6, and the cathode of the diode D4 is connected to the first end of the capacitor C4 and the first end of the resistor R13, which serves as the output end of the bootstrap power supply and outputs the second voltage VS1. The second voltage is used as a driving voltage to drive the subsequent high-side switch tube.

[0029] The second end of the capacitor C4 is connected to the collector of the switch tube Q5 as the negative power supply terminal VEE of the bootstrap power supply, the base of the switch tube Q5 is connected to the base of the switch tube Q6, the second end of the resistor R13, the first end of the resistor R14 and the collector of the switch tube Q7, the base of the switch tube Q7 is connected to the first end of the resistor R15 and the first end of the resistor R16, the second end of the resistor R15 is connected to the drive signal source Dri, and the second end of the resistor R16, the emitter of the switch tube Q7, the second end of the resistor R14 and the collector of the switch tube Q6 are connected to the reference ground GND.

[0030] Among them, capacitor C3, diode D3 and switch tube Q6 constitute a first bootstrap circuit, capacitor C4, diode D4 and switch tube Q5 constitute a second bootstrap circuit, switch tube Q7, resistor R13 and resistor R14 constitute a drive control circuit, wherein the first power supply VS is the driving power supply of the bootstrap power supply, which is used to drive the bootstrap power supply.

[0031] In the bootstrap power supply, when the driving signal output by the driving signal source Dri is at a high level, the control switch tube Q7 is turned on, the base of the switch tube Q6 is connected to the reference GND, the switch tube Q6 is turned on, and the first power supply VS charges the first bootstrap capacitor C3 through the diode D3 and the switch tube Q6, and the switch tube Q5 is in the cut-off state. At this time, the driving voltage VS1 of the high-side switch tube is maintained by the capacitor C4.

[0032] When the driving signal output by the driving signal source Dri is at a low level, the switch tube Q7 is controlled to be turned off. In this design, the resistor R14 is much larger than the resistor R13 (the resistor R13 and the resistor R14 divide the voltage to prevent the base of the switch tube Q5 and the switch tube Q6 from receiving high voltage and causing damage to the switch tube Q5 and the switch tube Q6). The switch tube Q5 is turned on, and the first bootstrap capacitor C3 charges the second bootstrap capacitor C4 through the diode D4 and the switch tube Q5 to maintain the driving voltage VS1 of the high-side switch tube. It should be noted that the capacitance (stored electricity) of the capacitor C3 and the capacitor C4 only needs to meet the power supply of the high-side switch tube switching process.

[0033] When the bootstrap capacitor in the bootstrap power supply is discharged, a voltage drop may occur, that is, voltage fluctuation occurs. The voltage fluctuation will be transmitted to the high-side MOS tube, causing the gate drive voltage of the high-side MOS tube to oscillate, resulting in insufficient drive voltage of the high-side MOS tube, thereby affecting the switching characteristics and reliability of the high-side MOS tube. To this end, the embodiment of the present application provides a protection circuit for a bootstrap power supply, and its structural schematic diagram is shown in FIG. Figure 2 As shown, the circuit includes a bootstrap module 110 , an undervoltage protection module 120 and a switch module 130 .

[0034] Among them, the power input end of the bootstrap module 110 is connected to the first power supply 20, the signal input end of the bootstrap module 110 is connected to the driving signal source 30, the input end of the undervoltage protection module 120 is connected to the output end of the bootstrap module 110, the input end of the switch module 130 is connected to the output end of the undervoltage protection module 120, and the output end of the switch module 130 is connected to the subsequent module 40.

[0035] Under the control of the driving signal output by the driving signal source 30, the first power supply 20 provides electric energy to the capacitor in the bootstrap module 110, so that the bootstrap module 110 outputs the second voltage; when and only when the second voltage is greater than the driving voltage threshold, the undervoltage protection module 120 controls the switch module 130 to turn on to output the driving voltage. When the second voltage is not greater than the driving voltage threshold, the undervoltage protection module 120 controls the switch module 130 to turn off to stop outputting the driving voltage.

[0036] Different from the prior art, the embodiment of the utility model provides an undervoltage protection module and a switch module, and uses the undervoltage protection module to control the switch module to limit the output lower limit of the driving voltage, thereby avoiding undervoltage of the high-side switch module, thereby improving the reliability of the bootstrap power supply.

[0037] Secondly, after the charger has established the output voltage, when the user operates improperly or the wiring is incorrect, the polarity is easily reversed. At this time, if the battery is mistakenly connected and the battery polarity is reversed, it will cause terrible safety hazards due to the violent discharge of the battery. To avoid such problems, the present application provides another protection circuit based on the protection circuit provided in the above embodiment, and its structural schematic diagram is shown in Figure 3. The other protection circuit includes a bootstrap module 110, an undervoltage protection module 120, a switch module 130 and a polarity protection module 140.

[0038] Among them, the power input end of the bootstrap module 110 is connected to the first power supply 20, the signal input end of the bootstrap module 110 is connected to the driving signal source 30, the input end of the undervoltage protection module 120 is connected to the output end of the bootstrap module 110, the input end of the switch module 130 is connected to the output end of the undervoltage protection module 120, and the output end of the switch module 130 is connected to the subsequent module 40. The first input end of the polarity protection module 140 is connected to the positive output end of the subsequent module 40, the second input end of the polarity protection module 140 is connected to the negative output end of the subsequent module 40, the first output end of the polarity protection module 140 is connected to the first signal end of the switch module 130, and the second output end of the polarity protection module 140 is connected to the second signal end of the switch module 130.

[0039] Under the control of the driving signal output by the driving signal source 30, the first power supply 20 provides electric energy to the capacitor in the bootstrap module 110 so that the bootstrap module 110 outputs the second voltage; when and only when the second voltage is greater than the driving voltage threshold, the undervoltage protection module 120 controls the switch module 130 to turn on to output the driving voltage. When the second voltage is not greater than the driving voltage threshold, the undervoltage protection module 120 controls the switch module 130 to turn off to stop outputting the driving voltage. When the second input terminal of the polarity protection module 140 receives a positive voltage, the first signal terminal and the second signal terminal of the polarity protection module 140 are turned on to turn off the switch module 130.

[0040] Different from the prior art, the embodiment of the utility model sets an undervoltage protection module and a switch module between the bootstrap module and the high-side switch module, and limits the output lower limit of the driving voltage by controlling the switch module to be turned on and off by the undervoltage protection module, thereby avoiding the high-side switch module from having an undervoltage condition; further, a polarity protection module is set, and when it is detected that the battery is connected and the polarity is reversed, the switch module is controlled to be disconnected, thereby preventing the safety hazard caused by the reverse connection of the battery. The safety and reliability of the bootstrap power supply are improved.

[0041] Figure 4 Shows Figure 2 , Figure 3 The circuit structure of the bootstrap module 110, the undervoltage protection module 120 and the switch module 130 in the protection circuit is shown.

[0042] In the embodiment of the present application, the bootstrap module 110 includes a resistor R13, a resistor R14, a resistor R15, a resistor R16, a diode D3, a diode D4, a capacitor C3, a capacitor C4, a switch tube Q5, a switch tube Q6 and a switch tube Q7; wherein the anode of the diode D3 is connected to the first power supply VS, the cathode of the diode D3 is connected to the anode of the diode D4 and the first end of the capacitor C3, the second end of the capacitor C3 is connected to the emitter of the switch tube Q5 and the emitter of the switch tube Q6, and the cathode of the diode D4 is connected to the first end of the capacitor C4 and the first end of the resistor R13, serving as the output end of the bootstrap module 110.

[0043] The second end of the capacitor C4 is connected to the collector of the switch tube Q5 as the negative power supply end of the bootstrap module 110, the base of the switch tube Q5 is connected to the base of the switch tube Q6, the second end of the resistor R13, the first end of the resistor R14 and the collector of the switch tube Q7, the base of the switch tube Q7 is connected to the first end of the resistor R15 and the first end of the resistor R16, the second end of the resistor R15 is connected to the drive signal source Dri, and the second end of the resistor R16, the emitter of the switch tube Q7, the second end of the resistor R14 and the collector of the switch tube Q6 are connected to the reference ground GND.

[0044] The undervoltage protection module 120 includes a resistor R6, a resistor R7 and a Zener diode DZ1; the cathode of the Zener diode DZ1 is connected to the output end of the bootstrap module 110 and the input end of the switch module 130, the anode of the Zener diode DZ1 is connected to the first end of the resistor R6, the second end of the resistor R6 serves as the output end of the undervoltage protection module 120, and is connected to the first end of the resistor R7 and the first signal end of the switch module 130; the second end of the resistor R7 is connected to the second signal end of the switch module 130 and the negative power supply end of the bootstrap module 110.

[0045] The switch module 130 includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a switch tube Q1, a switch tube Q2 and a diode D1; the emitter of the switch tube Q1 is connected to the output end of the bootstrap module 110 and the input end of the undervoltage protection module 120, the collector of the switch tube Q1 is connected to the first end of the resistor R1 and the second end of the resistor R3, the second end of the resistor R1 is connected to the first end of the resistor R5, as the second output end of the switch module 130, outputting the second driving voltage OUT_ON2; the second end of the resistor R3 is connected to the first end of the resistor R4, as the first output end of the switch module 130, outputting the first driving voltage OUT_ON1; the second end of the resistor R5 and the second end of the resistor R4 are connected to the anode of the diode D1, as the third output end OUT_H of the undervoltage protection module 120.

[0046] The base of the switch tube Q1 is connected to the first end of the resistor R2, the second end of the resistor R2 is connected to the drain of the switch tube Q2, the gate of the switch tube Q2 serves as the first signal terminal Repole of the switch module 130, and is connected to the output end of the undervoltage protection module 120; the source of the switch tube Q2 is connected to the cathode of the diode D1, and serves as the second signal terminal Repole_N of the switch module 130.

[0047] In the embodiment of the present application, the driving voltage threshold is the voltage stabilization value of the voltage stabilizing diode DZ1 and the driving voltage threshold of the switch tube Q2.

[0048] Specifically, when the second voltage VS1 is greater than the voltage stabilization value of the voltage stabilization diode DZ1, the voltage stabilization diode DZ1 is broken down and turned on, and the second voltage VS1 drives the switch tube Q2 to turn on through the voltage stabilization diode DZ1, and then drives the switch tube Q1 to turn on, so that the second voltage VS1 drives the high-side switch tube to turn on through the switch tube Q1. When the second voltage VS1 is less than the voltage stabilization value of the voltage stabilization diode DZ1, the voltage stabilization diode is cut off, and at this time the switch tube Q2 is in the cut-off state, and then drives the switch tube Q1 to be in the cut-off state, thereby playing the role of undervoltage protection.

[0049] The voltage regulator diode DZ1 is used to control the driving voltage of the switch tube Q2, and clamps the driving voltage of the switch tube Q2 from the second voltage VS1 to the second voltage VS1 minus the voltage regulator value of the voltage regulator diode DZ1, so that the switch tube Q1 can be controlled not to be turned on when the gate driving voltage is low. When turned on, the second voltage VS1 is greater than the driving voltage threshold of the switch tube Q2 plus the voltage regulator value of the voltage regulator diode DZ1. When it is lower than this voltage, the switch tube Q1 will not be turned on, thereby playing a role of undervoltage protection.

[0050] The function of resistor R6 is to reduce the current generated by the second voltage VS1 through the Zener diode DZ1, thereby ensuring that when the reverse polarity protection signal reaches the first new segment Repole of the switch module 130, it will not be clamped by the voltage generated by the second voltage VS1 minus the voltage stabilization value of the Zener diode DZ1, thereby ensuring that the reverse polarity protection function will not fail.

[0051] In the embodiment of the present application, the voltage stabilization value of the voltage stabilizing diode DZ1 is greater than 3.3 V. The purpose is to ensure that the driving voltage of the high-side switch is much greater than the required turn-on threshold.

[0052] Fig. 9A circuit structure of a high-side switch module is shown, and the high-side switch module 150 includes a resistor R8, a resistor R9, a capacitor C1, a capacitor C2, a switch tube Q3 and a switch tube Q4; wherein the first end of the resistor R8 is connected to the first power supply and the drain of the switch tube Q3, the second end of the resistor R8 is connected to the first end of the capacitor C1, and the second end of the capacitor C1 is connected to the first end of the resistor R9, the source of the switch tube Q3, the source of the switch tube Q4 and the third output terminal OUT_H of the switch module 130.

[0053] The second end of the resistor R9 is connected to the first end of the capacitor C2, the second end of the capacitor C2 is connected to the drain of the switch tube Q4, the gate of the switch tube Q3 is connected to the first output end OUT_ON1 of the switch module 130, the gate of the switch tube Q4 is connected to the second output end OUT_ON2 of the switch module 130, the drain of the switch tube Q4 serves as the positive output end Vout+ of the high-side switch module 150, and the ground end of the high-side switch module 150 serves as the negative output end Vout-.

[0054] The RC absorption circuit of the switch tubes Q3 and Q4 (including resistor R8, capacitor C1, resistor R9, and capacitor C2) is used to prevent the large voltage stress generated by the large current cutoff at the moment of shutdown from breaking down the switch tubes Q3 and Q4.

[0055] Figure 5 Shows Figure 3 The circuit structure of the polarity protection module in another protection circuit shown in the figure includes a resistor R10, a resistor R11, a resistor R12, an optocoupler U1 and a diode D2; the anode of the diode D2 is connected to the negative output end of the subsequent module 40, the cathode of the diode D2 is connected to the first end of the resistor R10, the second end of the resistor R10 is connected to the first end of the resistor R11 and the diode anode of the optocoupler U1, the second end of the resistor R11 is connected to the first end of the resistor R12 and the diode cathode of the optocoupler U1, the second end of the resistor R12 is connected to the positive output end of the subsequent module 40, the transistor collector of the optocoupler U1 is connected to the first signal end Repole of the switch module 130, and the transistor emitter of the optocoupler U1 is connected to the second signal end Repole_N of the switch module 130.

[0056] When the bootstrap power supply protection circuit drives the subsequent module to supply power to the load, if the power supply is connected by mistake and the power supply polarity is reversed, the signal at the positive output end of the subsequent module 40 is negative, and the signal at the negative output end of the subsequent module 40 is positive, so that the diode of the optocoupler U1 is turned on, and then the transistor in the optocoupler U1 is turned on, and the switch tube Q2 in the switch module 130 is turned off through the first signal terminal Repole and the second signal terminal Repole_N of the switch module 130, and then the switch tube Q1 is turned off to prevent the switch module 130 from outputting the second voltage VS1, thereby realizing the reverse polarity protection function. The role of the diode D2 is to cut off the current flowing from the resistor R12 to the resistor R11 and the resistor R10 to avoid safety problems.

[0057] Combination Fig. 9 When the reverse polarity protection circuit is added to the high-side switch module shown, since the output switch tube Q3 and the switch tube Q4 are on the high side of the circuit, isolation measures such as optocouplers are required to transmit the protection signal to the high side.

[0058] based on Figure 2 A bootstrap power supply protection circuit is provided. An embodiment of the present application provides an energy storage power supply, which includes a post-stage module 40 and a bootstrap power supply protection circuit including a bootstrap module 110, an undervoltage protection module 120 and a switch module 130.

[0059] Among them, the power input end of the bootstrap module 110 is connected to the first power supply 20, the signal input end of the bootstrap module 110 is connected to the driving signal source 30, the input end of the undervoltage protection module 120 is connected to the output end of the bootstrap module 110, the input end of the switch module 130 is connected to the output end of the undervoltage protection module 120, the power input end of the subsequent module 40 is connected to the first power supply 20, and the signal end of the subsequent module 40 is connected to the output end of the switch module 130 of the protection circuit of the bootstrap power supply; in response to the driving voltage output by the switch module 130, the subsequent module 40 outputs a supply voltage according to the first voltage input by the first power supply 20.

[0060] based on Figure 3 A bootstrap power supply protection circuit is provided. An embodiment of the present application provides an energy storage power supply, which includes a post-stage module 40 and a bootstrap power supply protection circuit including a bootstrap module 110, an undervoltage protection module 120, a switch module 130 and a polarity protection module 140.

[0061] Among them, the power input end of the bootstrap module 110 is connected to the first power supply 20, the signal input end of the bootstrap module 110 is connected to the driving signal source 30, the input end of the undervoltage protection module 120 is connected to the output end of the bootstrap module 110, and the input end of the switch module 130 is connected to the output end of the undervoltage protection module 120. The first input end of the polarity protection module 140 is connected to the positive output end of the subsequent module 40, the second input end of the polarity protection module 140 is connected to the negative output end of the subsequent module 40, the first output end of the polarity protection module 140 is connected to the first signal end of the switch module 130, and the second output end of the polarity protection module 140 is connected to the second signal end of the switch module 130. The power input end of the subsequent module 40 is connected to the first power supply 20, and the signal end of the subsequent module 40 is connected to the output end of the switch module 130 of the protection circuit of the bootstrap power supply; in response to the driving voltage output by the switch module 130, the subsequent module 40 outputs the supply voltage according to the first voltage input by the first power supply 20.

[0062] Figure 8 The structure of another energy storage power supply provided by an embodiment of the present application is shown. In the embodiment of the present application, the rear-stage module 40 is a high-side switch module 150, the power input end of the high-side switch module 150 is connected to the first power supply 20, the first signal end of the high-side switch module 150 is connected to the first output end of the undervoltage protection module 120, the second signal end of the high-side switch module 150 is connected to the second output end of the undervoltage protection module 120, and the third signal end of the high-side switch module 150 is connected to the third output end of the undervoltage protection module 120; in response to the first driving voltage or the second driving voltage output by the switch module 130, the high-side switch module 150 outputs a power supply voltage according to the first voltage output by the first power supply 20.

[0063] It should be noted that the preferred embodiments of the utility model are given in the specification and drawings of the utility model, but the utility model can be implemented in many different forms and is not limited to the embodiments described in the specification. These embodiments are not used as additional restrictions on the content of the utility model. The purpose of providing these embodiments is to make the understanding of the disclosure of the utility model more thorough and comprehensive. In addition, the above-mentioned technical features continue to be combined with each other to form various embodiments not listed above, which are all regarded as the scope of the description of the utility model; further, for ordinary technicians in this field, they can be improved or transformed according to the above description, and all these improvements and transformations should belong to the scope of protection of the claims attached to the utility model.

Claims

1. A protection circuit for a bootstrap power supply, characterized in that: include: Bootstrapping modules; The power input terminal of the bootstrap module is connected to a first power source, and the signal input terminal of the bootstrap module is connected to a driving signal source; Undervoltage protection module; The input end of the undervoltage protection module is connected to the output end of the bootstrap module; Switch module; The input end of the switch module is connected to the output end of the undervoltage protection module, and the output end of the switch module is connected to the subsequent module; Under the control of the driving signal output by the driving signal source, the first power supply provides electric energy to the capacitor in the bootstrap module, so that the bootstrap module outputs a second voltage; When and only when the second voltage is greater than a driving voltage threshold, the undervoltage protection module controls the switch module to be turned on to output a driving voltage.

2. The circuit according to claim 1, characterized in that Also includes: Polarity protection module; The first input end of the polarity protection module is connected to the positive output end of the subsequent module, the second input end of the polarity protection module is connected to the negative output end of the subsequent module, the first output end of the polarity protection module is connected to the first signal end of the switch module, and the second output end of the polarity protection module is connected to the second signal end of the switch module; When the second input terminal of the polarity protection module receives a positive voltage, the first signal terminal and the second signal terminal of the polarity protection module are turned on to turn off the switch module.

3. The circuit according to claim 1, characterized in that The output end of the switch module includes a first output end and a second output end, and the driving voltage includes a first driving voltage and a second driving voltage; The first output end of the switch module is connected to the first input end of the subsequent module, and the second output end of the switch module is connected to the second input end of the subsequent module; When and only when the second voltage is greater than the driving voltage threshold, the undervoltage protection module controls the switch module to turn on, so as to output the first driving voltage and the second driving voltage from the first output terminal of the switch module and the second output terminal of the switch module respectively.

4. The circuit according to claim 3, characterized in that The switch module includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a switch tube Q1, a switch tube Q2 and a diode D1; The emitter of the switch tube Q1 is connected to the output end of the bootstrap module and the input end of the undervoltage protection module, the collector of the switch tube Q1 is connected to the first end of the resistor R1 and the second end of the resistor R3, the second end of the resistor R1 is connected to the first end of the resistor R5, as the second output end of the switch module, outputting the second driving voltage; the second end of the resistor R3 is connected to the first end of the resistor R4, as the first output end of the switch module, outputting the first driving voltage; the second end of the resistor R5 and the second end of the resistor R4 are connected to the anode of the diode D1, as the third output end of the undervoltage protection module; The base of the switch tube Q1 is connected to the first end of the resistor R2, the second end of the resistor R2 is connected to the drain of the switch tube Q2, the gate of the switch tube Q2 serves as the first signal end of the switch module, and is connected to the output end of the undervoltage protection module; the source of the switch tube Q2 is connected to the cathode of the diode D1, and serves as the second signal end of the switch module.

5. The circuit according to claim 1, characterized in that The undervoltage protection module includes a resistor R6, a resistor R7 and a voltage stabilizing diode DZ1; Among them, the cathode of the voltage-stabilizing diode DZ1 is connected to the output end of the bootstrap module and the input end of the switch module, the anode of the voltage-stabilizing diode DZ1 is connected to the first end of the resistor R6, the second end of the resistor R6 serves as the output end of the undervoltage protection module, and is connected to the first end of the resistor R7 and the first signal end of the switch module; the second end of the resistor R7 is connected to the second signal end of the switch module and the negative power supply end of the bootstrap module.

6. The circuit according to claim 2, characterized in that The polarity protection module includes a resistor R10, a resistor R11, a resistor R12, an optical coupler U1 and a diode D2; Among them, the anode of the diode D2 is connected to the negative output end of the subsequent module, the cathode of the diode D2 is connected to the first end of the resistor R10, the second end of the resistor R10 is connected to the first end of the resistor R11 and the diode anode of the optocoupler U1, the second end of the resistor R11 is connected to the first end of the resistor R12 and the diode cathode of the optocoupler U1, the second end of the resistor R12 is connected to the positive output end of the subsequent module, the transistor collector of the optocoupler U1 is connected to the first signal end of the switch module, and the transistor emitter of the optocoupler U1 is connected to the second signal end of the switch module.

7. The circuit according to claim 1, characterized in that The bootstrap module includes a resistor R13, a resistor R14, a resistor R15, a resistor R16, a diode D3, a diode D4, a capacitor C3, a capacitor C4, a switch tube Q5, a switch tube Q6 and a switch tube Q7; The anode of the diode D3 is connected to the first power supply, the cathode of the diode D3 is connected to the anode of the diode D4 and the first end of the capacitor C3, the second end of the capacitor C3 is connected to the emitter of the switch tube Q5 and the emitter of the switch tube Q6, and the cathode of the diode D4 is connected to the first end of the capacitor C4 and the first end of the resistor R13, serving as the output end of the bootstrap module; The second end of the capacitor C4 is connected to the collector of the switch tube Q5 as the negative power supply end of the bootstrap module, the base of the switch tube Q5 is connected to the base of the switch tube Q6, the second end of the resistor R13, the first end of the resistor R14 and the collector of the switch tube Q7, the base of the switch tube Q7 is connected to the first end of the resistor R15 and the first end of the resistor R16, the second end of the resistor R15 is connected to the drive signal source, and the second end of the resistor R16, the emitter of the switch tube Q7, the second end of the resistor R14 and the collector of the switch tube Q6 are connected to the reference ground.

8. An energy storage power supply, characterized in that: include: Post-stage module; The protection circuit of the bootstrap power supply according to any one of claims 1 to 7; The power input terminal of the rear-stage module is connected to the first power supply, and the signal terminal of the rear-stage module is connected to the output terminal of the switch module of the protection circuit of the bootstrap power supply; In response to the driving voltage output by the switch module, the subsequent module outputs a supply voltage according to the first voltage input by the first power supply.

9. The energy storage power supply according to claim 8, characterized in that: The latter module comprises: A high-side switch module; the power input end of the high-side switch module is connected to the first power supply, the first signal end of the high-side switch module is connected to the first output end of the undervoltage protection module, the second signal end of the high-side switch module is connected to the second output end of the undervoltage protection module, and the third signal end of the high-side switch module is connected to the third output end of the undervoltage protection module; In response to the first driving voltage or the second driving voltage output by the switch module, the high-side switch module outputs the supply voltage according to the first voltage output by the first power supply.

10. The energy storage power supply according to claim 9, characterized in that: The high side switch module includes a resistor R8, a resistor R9, a capacitor C1, a capacitor C2, a switch tube Q3 and a switch tube Q4; The first end of the resistor R8 is connected to the first power supply and the drain of the switch tube Q3, the second end of the resistor R8 is connected to the first end of the capacitor C1, and the second end of the capacitor C1 is connected to the first end of the resistor R9, the source of the switch tube Q3, the source of the switch tube Q4 and the third output end of the switch module; The second end of the resistor R9 is connected to the first end of the capacitor C2, the second end of the capacitor C2 is connected to the drain of the switch tube Q4, the gate of the switch tube Q3 is connected to the first output end of the switch module, the gate of the switch tube Q4 is connected to the second output end of the switch module, the drain of the switch tube Q4 serves as the positive output end of the high-side switch module, and the ground end of the high-side switch module serves as the negative output end.

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