Voltage switching circuit and energy storage power supply

Abstract

The present application relates to a voltage switching circuit and an energy storage power supply. The voltage switching circuit includes a control chip, a reference voltage module connected to the control chip, and a power protection module; the control chip and the reference voltage module are both connected to the voltage conversion circuit and the power protection module; the reference voltage module is used to output a feedback reference voltage matching the target voltage to the control chip, and output a current limiting reference voltage corresponding to the current limit of the target voltage to the power protection module; the target voltage is any one of the multiple voltages supported by the voltage conversion circuit; the control chip is used to adjust the output voltage of the voltage conversion circuit to the target voltage according to the feedback reference voltage; the power protection module is used to trigger the control chip to stop working based on the current limiting reference voltage when the output power of the voltage conversion circuit exceeds the power limit. The use of this voltage switching circuit can solve the problem of poor scenario applicability.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and in particular to a voltage switching circuit and an energy storage power supply. Background Art

[0002] As one of the new energy products, energy storage power supply can provide power for outdoor environments without electricity. For example, when a traveler drives a motorhome for a long trip, he or she will inevitably need to use outdoor energy storage power supply to power the motorhome.

[0003] Generally, electrical equipment such as RVs require different voltages for their power supply interfaces, depending on their specifications and uses. For example, they can be 12Vdc or 24Vdc. However, the voltage output by the power supply interface of the energy storage power supply in the related art is often fixed, and the voltage output function is too single, resulting in the technical problem of poor scene applicability of the energy storage power supply in the related art. Summary of the invention

[0004] Based on this, it is necessary to provide a voltage switching circuit and an energy storage power supply to address the above technical problems, which can flexibly adjust the voltage output by the power interface of the energy storage power supply to solve the problem of poor scenario applicability.

[0005] In a first aspect, the present application provides a voltage switching circuit, which includes: a control chip, a reference voltage module connected to the control chip, and a power protection module; the control chip and the reference voltage module are both connected to the voltage conversion circuit and the power protection module;

[0006] A reference voltage module is used to output a feedback reference voltage matching the target voltage to the control chip, and to output a current limiting reference voltage corresponding to the current limit value of the target voltage to the power protection module; the target voltage is any one of the multiple voltages supported by the voltage conversion circuit;

[0007] A control chip, used for adjusting the output voltage of the voltage conversion circuit to a target voltage according to a feedback reference voltage;

[0008] The power protection module is used to trigger the control chip to stop working based on the current limiting reference voltage when the output power of the voltage conversion circuit exceeds the power limit.

[0009] In one of the embodiments, the voltage switching circuit further includes a voltage signal trigger, and the reference voltage module includes a reference voltage feedback unit and a current limit reference voltage unit; the reference voltage feedback unit is connected between the voltage signal trigger and the control chip, and the current limit reference voltage unit is connected between the voltage signal trigger and the power protection module;

[0010] A reference voltage feedback unit, used for outputting a feedback reference voltage to the control chip according to a target voltage signal input through a voltage signal trigger;

[0011] The current limit reference voltage unit is used to output a current limit reference voltage to the power protection module according to a target voltage signal input on the voltage signal trigger.

[0012] In one embodiment, the reference voltage feedback unit includes a first switch subunit and a first voltage divider subunit; a first end of the first switch subunit is connected to the voltage signal trigger, a second end of the first switch subunit is connected to the first end of the first voltage divider subunit, and a second end of the first voltage divider subunit is connected to the control chip and the voltage conversion circuit respectively;

[0013] The first voltage dividing subunit is used to divide the output voltage of the voltage conversion circuit to output a first reference voltage to the control chip when the target voltage signal triggered on the voltage signal trigger is at a low level and the first switch subunit is in an off state;

[0014] Furthermore, when the target voltage signal triggered on the voltage signal trigger is at a high level and the first switch subunit is in an on state, the output voltage of the voltage conversion circuit is divided to output a second reference voltage to the control chip.

[0015] In one embodiment, the first switch subunit includes a first switch tube, and the first voltage divider subunit includes a resistor 1, a resistor 2, and a resistor 3;

[0016] The gate of the first switch tube is connected to the voltage signal trigger, the drain of the first switch tube is connected to one end of resistor one, the other end of resistor one is connected between resistor two and resistor three, the other end of resistor two is respectively connected to the control chip and the voltage conversion circuit, and the other end of resistor three and the source of the first switch tube are both grounded.

[0017] In one embodiment, the current limit reference voltage unit includes a second switch subunit and a second voltage divider subunit; a first end of the second switch subunit is connected to the voltage signal trigger, a second end of the second switch subunit is connected to the first end of the second voltage divider subunit, and a second end of the second voltage divider subunit is connected to the power supply voltage and the power protection module respectively;

[0018] A second voltage dividing subunit, configured to divide the supply voltage when the target voltage signal triggered on the voltage signal trigger is at a low level, and output a first current limiting reference voltage to the power protection module when the second switch subunit is in an off state;

[0019] Furthermore, when the target voltage signal triggered on the voltage signal trigger is at a high level and the second switch subunit is in an on state, the supply voltage is divided to output a second current limiting reference voltage to the power protection module.

[0020] In one embodiment, the power protection module includes a voltage comparison unit and a current sampling unit; a first input end of the voltage comparison unit is connected to an output end of the reference voltage module, a second input end of the voltage comparison unit is connected to an output end of the current sampling unit, an input end of the current sampling unit is connected to a voltage conversion circuit, and an output end of the voltage comparison unit is connected to a control chip;

[0021] A current sampling unit, used for sampling the output current of the voltage conversion circuit and converting the output current into a voltage signal;

[0022] The voltage comparison unit is used to trigger the control chip to stop working according to the voltage signal and the current limiting reference voltage when the output current of the voltage conversion circuit exceeds the current limit of the target voltage.

[0023] In one embodiment, the current sampling unit includes an operational amplifier unit and a filter unit; a first input terminal and a second input terminal of the operational amplifier unit are connected to two ends of a sampling resistor in a voltage conversion circuit, an output terminal of the operational amplifier unit is connected to an input terminal of the filter unit, and an output terminal of the filter unit is connected to a second input terminal of the voltage comparison unit;

[0024] The operational amplifier subunit is used to amplify the voltage difference formed by the output current in the collected voltage conversion circuit flowing through the sampling resistor;

[0025] The filter subunit is used to filter the voltage difference amplified and output by the operational amplifier subunit and input it into the voltage comparison unit as a voltage signal.

[0026] In one embodiment, the voltage comparison unit includes a comparator and a third switch subunit, the inverting input terminal of the comparator is connected to the output terminal of the reference voltage module, the non-inverting input terminal of the comparator is connected to the output terminal of the current sampling unit, the output terminal of the comparator is connected to the first terminal of the third switch subunit, the second terminal of the third switch subunit is connected to the enable terminal of the control chip, and the third terminal of the third switch subunit is grounded;

[0027] A comparator, used to output a high level when the voltage at the non-inverting input terminal is greater than the voltage at the inverting input terminal;

[0028] The third switch sub-unit is in a conducting state when the comparator outputs a high level, and is used to pull down the level of the enable terminal of the control chip to stop the control chip from working.

[0029] In one of the embodiments, the power protection module further includes a self-locking unit, a first end of the self-locking unit is connected to the power supply voltage, and a second end of the self-locking unit is connected to the voltage comparison unit;

[0030] The self-locking unit is used to continuously lock the control chip in a stopped state when the control chip is triggered to stop working.

[0031] In a second aspect, the present application further provides an energy storage power supply, which includes the content of any one embodiment of the voltage switching circuit in the above-mentioned first aspect.

[0032] The above-mentioned voltage switching circuit and energy storage power supply, the voltage switching circuit includes: a control chip, a reference voltage module connected to the control chip, and a power protection module; the control chip and the reference voltage module are both connected to the voltage conversion circuit and the power protection module; the reference voltage module is used to output a feedback reference voltage matching the target voltage to the control chip, and output a current limiting reference voltage corresponding to the current limit of the target voltage to the power protection module; the target voltage is any one of the multiple voltages supported by the voltage conversion circuit; the control chip is used to adjust the output voltage of the voltage conversion circuit to the target voltage according to the feedback reference voltage; the power protection module is used to trigger the control chip to stop working based on the current limiting reference voltage when the output power of the voltage conversion circuit exceeds the power limit. A voltage switching circuit is added on the basis of the voltage conversion circuit, and the reference voltage module in the voltage switching circuit can generate a matching feedback reference voltage based on the target voltage corresponding to different types of RVs, so that the control chip can adjust the output voltage of the voltage conversion circuit to the target voltage based on the feedback reference voltage. That is to say, through a voltage conversion circuit, different target voltages can be switched, so that the power interface of the energy storage power supply outputs different voltages to meet different types of charging or power supply requirements, enrich the voltage output function, and improve the scenario applicability of the energy storage power supply. At the same time, the reference voltage module generates a matching current limiting reference voltage based on the current limit of the target voltage corresponding to different types of RVs. The power protection module uses the current limiting reference voltage as a limiting condition to determine whether the output power of the voltage conversion circuit exceeds the power limit, so that the control chip stops working when the power limit is exceeded, so as to protect the voltage conversion circuit and improve the working safety of the voltage conversion circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 is a schematic diagram of a voltage conversion circuit in one embodiment;

[0035] Figure 2 is a first schematic diagram of a voltage switching circuit in one embodiment;

[0036] Figure 3 is a second schematic diagram of a voltage switching circuit in one embodiment;

[0037] Figure 4 is a third schematic diagram of a voltage switching circuit in one embodiment;

[0038] Figure 5 is a fourth schematic diagram of a voltage switching circuit in one embodiment;

[0039] Figure 6 is a fifth schematic diagram of a voltage switching circuit in one embodiment;

[0040] Figure 7 is a sixth schematic diagram of a voltage switching circuit in one embodiment;

[0041] Figure 8 is a seventh schematic diagram of a voltage switching circuit in one embodiment;

[0042] Fig. 9 is an eighth schematic diagram of a voltage switching circuit in one embodiment;

[0043] Fig.10 is a ninth schematic diagram of a voltage switching circuit in one embodiment;

[0044] Fig.11 is a tenth schematic diagram of a voltage switching circuit in one embodiment;

[0045] Fig.12 is an eleventh schematic diagram of a voltage switching circuit in one embodiment;

[0046] Fig.13 FIG. 12 is a twelfth schematic diagram of a voltage switching circuit in an embodiment.

[0047] Description of reference numerals:

[0048] 10: Voltage conversion circuit;

[0049] 11: voltage switching circuit;

[0050] 12: Control chip;

[0051] 13: Reference voltage module;

[0052] 131: reference voltage feedback unit;

[0053] 1311: first switch subunit;

[0054] 1312: first voltage dividing subunit;

[0055] 132: current limit reference voltage unit;

[0056] 1321: second switch subunit;

[0057] 1322: second voltage dividing subunit;

[0058] 14: Power protection module;

[0059] 141: voltage comparison unit;

[0060] 1411: a third switch subunit;

[0061] 142: current sampling unit;

[0062] 1421: operational amplifier subunit;

[0063] 1422: filter subunit;

[0064] 143: Self-locking unit;

[0065] 15: Voltage signal trigger. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0067] In the description of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present application, "plurality" means at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0068] In this application, unless otherwise clearly defined and specified, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be an electrical connection, a direct connection, or an indirect connection through an intermediate medium, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0069] Before introducing the technical solution of the present application in detail, a brief introduction to the background technology of the present application is first given.

[0070] With the continuous development of energy storage technology, energy storage power supplies can meet the power needs of electrical equipment in various application scenarios. Taking the RV scenario as an example, the energy storage power supply is connected to the power supply interface of the RV to ensure the normal operation of the electrical equipment in the RV. However, the power supply voltage required by the power supply interface of different types of RVs is also different. For example, it can be 12Vdc power supply or 24Vdc power supply.

[0071] In the related art, the voltage output by the power interface of the energy storage power supply is often fixed, that is, the output voltage is 12Vdc or 24Vdc. Assuming that the output power of the power interface of the energy storage power supply is 600W, for the power interface with an output voltage of 12Vdc, its current limit is 50A; for the power interface with an output voltage of 24Vdc, its current limit is 25A. Figure 1 A schematic diagram of a voltage conversion circuit is shown. The voltage conversion circuit 10 represents the circuit of the power interface of the energy storage power supply. The topology used in the circuit is a buck conversion (BUCK) circuit. The voltage between RV+ and RV- in the figure represents the output voltage of the power interface. The sampling resistor in the figure represents the sampling resistor of the output current. The sampling current is obtained by sampling the current flowing through the sampling resistor. The sampling current represents the output current of the energy storage power supply when it is loaded. By judging whether the output current exceeds the current limit, it can be judged whether there may be safety hazards in the operation of the energy storage power supply. Vin given in the figure represents the input voltage. Two metal oxide semiconductor field effect transistors (MOS tubes), an inductor, and two capacitors are used to convert Vin into the required output voltage.

[0072] However, the power interface of the energy storage power supply is set to a fixed output voltage, which will cause the function of the energy storage power supply to be relatively single, resulting in the energy storage power supply having poor scene applicability.

[0073] In response to the above problems, the present application provides a voltage switching circuit and an energy storage power supply, which can flexibly adjust the voltage output by the power interface of the energy storage power supply to solve the problem of poor scenario applicability. At the same time, by setting a power protection module, the safety of the voltage conversion circuit 10 during the power supply process can be guaranteed. Of course, the technical solution provided in the embodiments of the present application is not limited to solving only the above problems, and there are other technical effects. For details, please refer to the following embodiment description. The technical solution of the present application is described in detail below.

[0074] In one embodiment, Figure 2As shown, a voltage switching circuit 11 is provided, which is applied to a voltage conversion circuit 10. The voltage switching circuit 11 includes: a control chip 12, a reference voltage module 13 connected to the control chip 12, and a power protection module 14; the control chip 12 and the reference voltage module 13 are both connected to the voltage conversion circuit 10 and the power protection module 14;

[0075] The reference voltage module 13 is used to output a feedback reference voltage V matching the target voltage to the control chip 12. FB , and outputs a current limiting reference voltage V corresponding to the current limit value of the target voltage to the power protection module 14 ref ; The target voltage is any one of the multiple voltages supported by the voltage conversion circuit 10 for output;

[0076] The control chip 12 is used to feedback the reference voltage V FB Adjusting the output voltage of the voltage conversion circuit 10 to a target voltage;

[0077] The power protection module 14 is used to limit the current based on the reference voltage V ref When the output power of the voltage conversion circuit 10 exceeds the power limit, the control chip 12 is triggered to stop working.

[0078] In the embodiment of the present application, the voltage switching circuit 11 is a circuit for switching the output voltage of the power interface of the energy storage power supply, and the needs of different types of RVs are met by switching the output voltage. For example, the power supply interfaces of different RVs include 12Vdc power supply or 24Vdc power supply. Assuming that the power supply interface of RV A is 12Vdc power supply, and the power supply interface of RV B is 24Vdc power supply, RV A is disconnected from the energy storage power supply, and the energy storage power supply is connected to RV B. Before powering the electrical equipment in RV B, the voltage switching circuit 11 needs to switch the output voltage of the voltage conversion circuit 10 from 12Vdc to 24Vdc.

[0079] In the voltage switching circuit 11 , the control chip 12 is connected to the voltage conversion circuit 10 , the power protection module 14 , and the reference voltage module 13 , respectively. The reference voltage module 13 is connected to the voltage conversion circuit 10 and the power protection module 14 , respectively.

[0080] If the RV needs to be charged, the voltage of the power supply interface corresponding to the RV can be selected through the key switch, and the voltage of the power supply interface is determined as the target voltage. After the user presses the key switch, a switching instruction corresponding to the target voltage is generated. After receiving the switching instruction, the reference voltage module 13 turns on part of the internal circuit, so that the voltage output by the reference voltage module 13 to the control chip 12 is the feedback reference voltage V FB It should be noted that the feedback reference voltage V FBThere is a mapping relationship between the voltage conversion circuit 10 and the output voltage.

[0081] When the control chip 12 receives the feedback reference voltage V FB After that, the output voltage of the voltage conversion circuit 10 can be determined based on the above mapping relationship. And based on the voltage difference between the output voltage and the target voltage, the duty cycle of the control signal is adjusted to adjust the output voltage of the voltage conversion circuit 10 to the target voltage by adjusting the control signal. For example, the control chip 12 can be, but is not limited to, a pulse width modulation (PWM) control chip, a control integrated circuit (IC), a voltage reference source, a phase locked loop (PLL) control chip, a current detection chip, a metal-oxide-semiconductor field-effect transistor (MOSFET) driver chip, etc. Among them, the duty cycle D can be expressed as:

[0082]

[0083] in, Indicates the positive output voltage of the voltage conversion circuit; Indicates the input voltage of the voltage conversion circuit.

[0084] At the same time, after receiving the switching instruction, the reference voltage module 13 turns on part of the internal circuit so that the voltage output by the reference voltage module 13 to the power protection module 14 is the current limiting reference voltage V ref , the current limiting reference voltage V ref Refers to the voltage corresponding to the current limit of the target voltage.

[0085] The power protection module 14 receives the current limiting reference voltage V ref After that, the voltage across the sampling resistor is determined based on the sampling current flowing through the sampling resistor and the resistance value of the sampling resistor. Then the voltage across the sampling resistor is amplified and compared with the current limiting reference voltage V ref Compare and get the comparison result. ref It is the voltage corresponding to the current limit value of the target voltage. Therefore, according to the above comparison result, it can be determined whether the voltage across the sampling resistor exceeds the current limiting reference voltage V ref, so that it can be determined whether the actual output current of the voltage conversion circuit 10 exceeds the current limit, and then it can be determined whether the output power of the voltage conversion circuit 10 exceeds the power limit. If it is determined that the output power does not exceed the power limit, it means that the voltage conversion circuit 10 is in a safe power supply environment, and at this time, the control chip 12 works normally. If it is determined that the output power exceeds the power limit, it means that there may be safety hazards in the working process of the voltage conversion circuit 10, and at this time, the control chip 12 stops working. Among them, the power protection module 14 can be composed of a comparator and other electronic components.

[0086] The voltage switching circuit 11 includes: a control chip 12, a reference voltage module 13 connected to the control chip 12, and a power protection module 14; the control chip 12 and the reference voltage module 13 are both connected to the voltage conversion circuit 10 and the power protection module 14; the reference voltage module 13 is used to output a feedback reference voltage V matching the target voltage to the control chip 12 FB , and outputs a current limiting reference voltage V corresponding to the current limit value of the target voltage to the power protection module 14 ref The target voltage is any one of the multiple voltages supported by the voltage conversion circuit 10; the control chip 12 is used to feedback the reference voltage V FB Adjust the output voltage of the voltage conversion circuit 10 to the target voltage; the power protection module 14 is used to adjust the output voltage of the voltage conversion circuit 10 to the target voltage based on the current limiting reference voltage V ref When the output power of the voltage conversion circuit 10 exceeds the power limit, the trigger control chip 12 stops working. A voltage switching circuit 11 is added on the basis of the voltage conversion circuit 10. Through the reference voltage module 13 in the voltage switching circuit 11, a matching feedback reference voltage V can be generated based on the target voltage corresponding to different types of RVs. FB , so that the control chip 12 can be based on the feedback reference voltage V FB The output voltage of the voltage conversion circuit 10 is adjusted to the target voltage. In other words, different target voltages can be switched through a voltage conversion circuit 10, so that the power interface of the energy storage power supply outputs different voltages to meet different types of charging or power supply requirements, enrich the voltage output function, and improve the scenario applicability of the energy storage power supply. At the same time, the reference voltage module 13 generates a matching current limiting reference voltage V based on the current limit value of the target voltage corresponding to different types of RVs. ref , the power protection module 14 uses the current limiting reference voltage V ref As a restriction condition, it is possible to determine whether the output power of the voltage conversion circuit 10 exceeds the power limit, so that the control chip 12 stops working when the power limit is exceeded, so as to protect the voltage conversion circuit 10 and improve the working safety of the voltage conversion circuit 10.

[0087] Next, the specific contents of the reference voltage module 13 are introduced through an embodiment. Figure 3 As shown, the voltage switching circuit 11 also includes a voltage signal trigger 15, and the reference voltage module 13 includes a reference voltage feedback unit 131 and a current limit reference voltage unit 132; the reference voltage feedback unit 131 is connected between the voltage signal trigger 15 and the control chip 12, and the current limit reference voltage unit 132 is connected between the voltage signal trigger 15 and the power protection module 14;

[0088] The reference voltage feedback unit 131 is used to output a feedback reference voltage V to the control chip 12 according to the target voltage signal input through the voltage signal trigger 15. FB ;

[0089] The current limit reference voltage unit 132 is used to output a current limit reference voltage V to the power protection module 14 according to the target voltage signal input on the voltage signal trigger 15. ref .

[0090] The power supply process of the energy storage power supply mainly includes two steps. The first step is to adjust the output voltage of the voltage conversion circuit 10 to the target voltage through the control chip 12. The second step is the protection process of the voltage conversion circuit 10 in the energy storage power supply through the power protection module 14 during the power supply of the energy storage power supply. Based on these two steps, the reference voltage module 13 can be divided to obtain a reference voltage feedback unit 131 and a current limit reference voltage unit 132. The reference voltage feedback unit 131 is combined with the control chip 12 to adjust the output voltage of the voltage conversion circuit 10. The current limit reference voltage unit 132 is combined with the power protection module 14 to protect the safety of the voltage conversion circuit 10.

[0091] Based on this, the voltage signal trigger 15 is respectively connected to the input end of the reference voltage feedback unit 131 and the input end of the current limit reference voltage unit 132, the output end of the reference voltage feedback unit 131 is connected to the control chip 12, and the output end of the current limit reference voltage unit 132 is connected to the power protection module 14.

[0092] The voltage signal trigger 15 receives the target voltage required by the user and outputs a corresponding target voltage signal according to the target voltage, that is, the user can operate the voltage signal trigger 15 to output the corresponding target voltage signal and perform target voltage switching. For example, the voltage signal trigger 15 is a key switch. The user can perform target voltage switching by pressing the key switch; for another example, the voltage signal trigger 15 can be a controller, and the user outputs the target voltage signal through the controller.

[0093] When the voltage signal trigger 15 triggers the target voltage signal, the reference voltage feedback unit 131 can use the internal electronic components to output the feedback reference voltage V corresponding to the target voltage signal. FB , and the feedback reference voltage V FB The current limit reference voltage unit 132 can output the current limit reference voltage V corresponding to the target voltage signal by using the internal electronic components. ref .

[0094] The voltage switching circuit 11 further includes a voltage signal trigger 15, and the reference voltage module 13 includes a reference voltage feedback unit 131 and a current limit reference voltage unit 132; the reference voltage feedback unit 131 is connected between the voltage signal trigger 15 and the control chip 12, and the current limit reference voltage unit 132 is connected between the voltage signal trigger 15 and the power protection module 14; the reference voltage feedback unit 131 is used to output a feedback reference voltage V to the control chip 12 according to the target voltage signal input through the voltage signal trigger 15. FB Current limit reference voltage unit 132, for outputting a current limit reference voltage V to the power protection module 14 according to the target voltage signal input on the voltage signal trigger 15 ref During the voltage switching process, the reference voltage module 13 is divided into two different units, which are respectively connected to the control chip 12 and the power protection module 14 to realize voltage switching and protection of the voltage conversion circuit 10. In this way, the energy storage system can not only meet different types of power demand, but also protect the voltage conversion circuit 10 during the power supply process to improve the safety of the energy storage system during operation.

[0095] In the above embodiment, it is mentioned that the reference voltage module 13 includes a reference voltage feedback unit 131 and a current limit reference voltage unit 132 . Next, the specific contents of the reference voltage feedback unit 131 and the current limit reference voltage unit 132 are introduced through different embodiments.

[0096] First, the content of the reference voltage feedback unit 131 is introduced. Figure 4 As shown, the reference voltage feedback unit 131 includes a first switch subunit 1311 and a first voltage divider subunit 1312; a first end of the first switch subunit 1311 is connected to the voltage signal trigger 15, a second end of the first switch subunit 1311 is connected to a first end of the first voltage divider subunit 1312, and a second end of the first voltage divider subunit 1312 is connected to the control chip 12 and the voltage conversion circuit 10 respectively;

[0097] The first voltage dividing subunit 1312 is used to divide the output voltage of the voltage conversion circuit 10 when the target voltage signal triggered on the voltage signal trigger 15 is at a low level and the first switch subunit 1311 is in the off state, so as to output the first feedback reference voltage V to the control chip. FB1 When the target voltage signal triggered on the voltage signal trigger 15 is at a high level and the first switch subunit 1311 is in the on state, the output voltage of the voltage conversion circuit 10 is divided to output the second feedback reference voltage V to the control chip 12. FB2 .

[0098] In the embodiment of the present application, the target voltage signal is divided into a high level signal and a low level signal. For example, when the target voltage signal is 12Vdc, it is determined to be a low level; when the target voltage signal is 24Vdc, it is determined to be a high level.

[0099] Further, when it is determined that the target voltage signal is at a low level, the first switch subunit 1311 is not turned on. At this time, the first voltage divider subunit 1312 is connected to the control chip 12, and the first voltage divider subunit 1312 can divide the output voltage of the voltage conversion circuit 10 and output the first feedback reference voltage V to the control chip 12. FB1 .

[0100] When it is determined that the target voltage signal is at a high level, the first switch subunit 1311 is turned on. At this time, the first switch subunit 1311 is connected to the control chip 12 through the first voltage divider subunit 1312. Similarly, the first voltage divider subunit 1312 can divide the output voltage of the voltage conversion circuit 10 and output the second feedback reference voltage V to the control chip 12. FB2 .

[0101] Among them, the first switch subunit 1311 can be implemented by a switch tube, for example, a triode, a MOS, etc. Alternatively, it can also be implemented by various types of switches, etc. Alternatively, it can also be implemented by some switch chips. The embodiment of the present application does not limit the components in the first switch subunit 1311. The first voltage divider subunit 1312 can be obtained by connecting at least two fixed resistance resistors in series or in parallel.

[0102] The reference voltage feedback unit 131 includes a first switch subunit 1311 and a first voltage divider subunit 1312; the first end of the first switch subunit 1311 is connected to the voltage signal trigger 15, the second end of the first switch subunit 1311 is connected to the first end of the first voltage divider subunit 1312, and the second end of the first voltage divider subunit 1312 is connected to the control chip 12 and the voltage conversion circuit 10 respectively; the first voltage divider subunit 1312 is used to divide the output voltage of the voltage conversion circuit 10 when the target voltage signal triggered on the voltage signal trigger 15 is a low level and the first switch subunit 1311 is in the cut-off state, so as to output the first feedback reference voltage V to the control chip. FB1 When the target voltage signal triggered on the voltage signal trigger 15 is at a high level and the first switch subunit 1311 is in the on state, the output voltage of the voltage conversion circuit 10 is divided to output the second feedback reference voltage V to the control chip 12. FB2 The high and low levels of the target voltage signal triggered by the voltage signal trigger 15 are used to control whether the first switch subunit 1311 is turned on, and based on the turn-on result of the first switch subunit 1311, the reference voltage V output by the reference voltage feedback unit 131 to the control chip 12 can be accurately determined. FB .

[0103] In one embodiment, Figure 5 As shown, the first switch subunit 1311 includes a first switch tube Q1, and the first voltage divider subunit 1312 includes a resistor R1, a resistor R2 and a resistor R3; the gate of the first switch tube Q1 is connected to the voltage signal trigger 15, the drain of the first switch tube Q1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected between the resistor R2 and the resistor R3, the other end of the resistor R2 is respectively connected to the control chip 12 and the voltage conversion circuit 10, and the other end of the resistor R3 and the source of the first switch tube Q1 are both grounded.

[0104] The first switch subunit 1311 may include only one switch tube, or may include one switch tube and multiple resistors. For example, the switch tube may be a MOS tube.

[0105] When the target voltage signal triggered on the voltage signal trigger 15 is at a low level, the first switch tube Q1 is in the off state. At this time, the resistor R2 and the resistor R3 divide the RV+ voltage (the positive voltage of the output voltage of the voltage conversion circuit 10), so the first feedback reference voltage V input to the control chip 12 is FB1 is the voltage value of resistor R3 to ground, the first feedback reference voltage V FB1 It can be expressed as:

[0106]

[0107] At this time, the first feedback reference voltage V FB1 It can represent the actual voltage corresponding to the RV+ voltage. The control chip 12 is based on the first feedback reference voltage V FB1 The duty cycle of the control signal is adjusted so that the output voltage of the voltage conversion circuit 10 approaches 12 Vdc.

[0108] When the target voltage signal triggered on the voltage signal trigger 15 is at a high level, the first switch tube Q1 is in the on state. At this time, the resistor 1 R1 and the resistor 3 R3 are connected in parallel and then connected in series with the resistor 2 R2. The RV+ voltage is divided by the combination of the three resistors. Then, the second feedback reference voltage V input to the control chip 12 is FB2 is the voltage value to ground after resistor 1 R1 and resistor 3 R3 are connected in parallel. The second feedback reference voltage V FB2 It can be expressed as:

[0109]

[0110] At this time, the second feedback reference voltage V FB2 It can represent the actual voltage corresponding to the RV+ voltage. The control chip 12 is based on the second feedback reference voltage V FB2 The duty cycle of the control signal is adjusted so that the output voltage of the voltage conversion circuit 10 approaches 24 Vdc.

[0111] The first switch subunit 1311 includes a first switch tube Q1, and the first voltage divider subunit 1312 includes a resistor R1, a resistor R2, and a resistor R3; the gate of the first switch tube Q1 is connected to the voltage signal trigger 15, the drain of the first switch tube Q1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected between the resistor R2 and the resistor R3, the other end of the resistor R2 is connected to the control chip 12 and the voltage conversion circuit 10, respectively, and the other end of the resistor R3 and the source of the first switch tube Q1 are both grounded. The conduction state of the first switch tube Q1 is controlled by the high and low levels of the target voltage signal received on the voltage signal trigger 15, and according to the conduction state and the connection mode of the three resistors, the first feedback reference voltage V can be accurately sent to the control chip 12. FB1 Or the second feedback reference voltage V FB2 .

[0112] Next, the specific contents of the current limit reference voltage unit 132 are described in detail. In one embodiment, Figure 6As shown, the current limit reference voltage unit 132 includes a second switch subunit 1321 and a second voltage dividing subunit 1322; the first end of the second switch subunit 1321 is connected to the voltage signal trigger 15, the second end of the second switch subunit 1321 is connected to the first end of the second voltage dividing subunit 1322, and the second end of the second voltage dividing subunit 1322 is respectively connected to the power supply voltage VCC and the power protection module 14;

[0113] The second voltage dividing subunit 1322 is used to divide the supply voltage VCC when the target voltage signal triggered on the voltage signal trigger 15 is at a low level and the second switch subunit 1321 is in the cut-off state, so as to output the first current limiting reference voltage V to the power protection module 14. ref1 When the target voltage signal triggered on the voltage signal trigger 15 is at a high level and the second switch subunit 1321 is in the on state, the supply voltage VCC is divided to output a second current limiting reference voltage V to the power protection module 14. ref2 .

[0114] It should be noted that after the target voltage signal is triggered on the voltage signal trigger 15 , the current limit reference voltage unit 132 and the reference voltage feedback unit 131 will work respectively.

[0115] When it is determined that the target voltage signal is at a low level, the second switch subunit 1321 is in the same state as the first switch subunit 1311, both of which are in a non-conducting state. At this time, the second voltage divider subunit 1322 is connected to the power protection module 14, and the second voltage divider subunit 1322 can divide the power supply voltage VCC and output the first current limiting reference voltage VCC to the power protection module 14. ref1 .

[0116] When it is determined that the target voltage signal is at a high level, the second switch subunit 1321 is still in the same state as the first switch subunit 1311, both of which are in the on state. At this time, the second switch subunit 1321 is connected to the power protection module 14. Similarly, the second voltage divider subunit 1322 can divide the power supply voltage VCC and output the second current limiting reference voltage V to the power protection module 14. ref2 .

[0117] The conduction state of the second switch subunit 1321 is consistent with that of the first switch subunit 1311, and the second switch subunit 1321 can also be implemented by a switch tube, a mechanical switch or a switch chip, etc. The second voltage divider subunit 1322 can also be obtained by connecting at least two fixed resistance resistors in series or in parallel.

[0118] In one embodiment, the specific content of the second voltage dividing subunit 1322 is introduced as follows: Figure 7As shown, the second switch subunit 1321 includes a second switch tube Q2, and the second voltage divider subunit 1322 includes a resistor four R4, a resistor five R5 and a resistor six R6; the gate of the second switch tube Q2 is connected to the voltage signal trigger 15, the drain of the second switch tube Q2 is connected to one end of the resistor four R4, the other end of the resistor four R4 is connected between the resistor five R5 and the resistor six R6, the other end of the resistor five R5 is respectively connected to the power supply voltage VCC and the power port of the energy storage power supply, and the other end of the resistor six R6 and the source of the second switch tube Q2 are both grounded.

[0119] Similar to the first switch subunit 1311, the second switch subunit 1321 may include only one switch tube, or may include one switch tube and a plurality of resistors. For example, the switch tube may be a MOS tube.

[0120] When the target voltage signal triggered on the voltage signal trigger 15 is at a low level, the second switch tube Q2 is in the off state. At this time, the resistor five R5 and the resistor six R6 divide the supply voltage VCC, and the first current limiting reference voltage V ref1 represents the voltage value of the resistor R6 to the ground, then the first current limiting reference voltage V input to the power protection module 14 ref1 is the voltage value of the resistor R6 to ground, the first current limiting reference voltage V ref1 It can be expressed as:

[0121]

[0122] At this time, the first current limiting reference voltage V ref1 It represents the voltage corresponding to the current limit value corresponding to the target voltage. For example, when the output power of the voltage conversion circuit 10 is 600W and the output voltage is 12V, the current limit value is 50A.

[0123] When the target voltage signal triggered on the voltage signal trigger 15 is at a high level, the second switch tube Q2 is in the on state. At this time, the resistors R4 and R6 are connected in parallel and then connected in series with the resistor R5. The power supply voltage VCC is divided by the combination of the three resistors. Then, the second current limiting reference voltage V ref2 is the voltage value of the resistor 4 R4 and the resistor 6 R6 connected in parallel to the ground. The second current limiting reference voltage V ref2 It can be expressed as:

[0124]

[0125] At this time, the second current limiting reference voltage V ref2 It represents the voltage corresponding to the current limit value corresponding to the target voltage. For example, when the output power of the voltage conversion circuit 10 is 600W and the output voltage is 24V, the current limit value is 25A.

[0126] The above-mentioned current limit reference voltage unit 132 includes a second switch subunit 1321 and a second voltage dividing subunit 1322; the first end of the second switch subunit 1321 is connected to the voltage signal trigger 15, the second end of the second switch subunit 1321 is connected to the first end of the second voltage dividing subunit 1322, and the second end of the second voltage dividing subunit 1322 is respectively connected to the power supply voltage VCC and the power protection module 14; the second voltage dividing subunit 1322 is used to divide the power supply voltage VCC when the target voltage signal triggered on the voltage signal trigger 15 is a low level and the second switch subunit 1321 is in the cut-off state, so as to output the first current limiting reference voltage V to the power protection module 14. ref1 When the target voltage signal triggered on the voltage signal trigger 15 is at a high level and the second switch subunit 1321 is in the on state, the supply voltage VCC is divided to output a second current limiting reference voltage V to the power protection module 14. ref2 The high and low levels of the target voltage signal received on the voltage signal trigger 15 are used to control whether the second switch subunit 1321 is turned on, and based on the turn-on result of the second switch subunit 1321, the current limiting reference voltage V output by the reference voltage feedback unit 131 to the power protection module 14 can be accurately determined. ref , so that the current limiting reference voltage V ref The output power of the voltage conversion circuit 10 is protected to improve the safety of the working process of the energy storage power supply.

[0127] After the specific content of the reference voltage module 13 is introduced, the specific content of the power protection module 14 is introduced next. The power protection module 14 is mainly used to protect the voltage conversion circuit 10 during operation. In one embodiment, Figure 8 As shown, the power protection module 14 includes a voltage comparison unit 141 and a current sampling unit 142; the first input end of the voltage comparison unit 141 is connected to the output end of the reference voltage module 13, the second input end of the voltage comparison unit 141 is connected to the output end of the current sampling unit 142, the input end of the current sampling unit 142 is connected to the voltage conversion circuit 10, and the output end of the voltage comparison unit 141 is connected to the control chip 12;

[0128] The current sampling unit 142 is used to sample the output current of the voltage conversion circuit 10 and convert the output current into a voltage signal;

[0129] The voltage comparison unit 141 is used to compare the voltage signal and the current limiting reference voltage V ref When the output current of the voltage conversion circuit 10 exceeds the current limit of the target voltage, the trigger control chip 12 stops working.

[0130] In the embodiment of the present application, the power protection module 14 needs to determine whether the output power of the voltage conversion circuit 10 exceeds the power limit during the protection of the voltage conversion circuit 10. If the judgment result is that the output power does not exceed the power limit, the control chip 12 works normally; if the judgment result is that the output power exceeds the power limit, the control chip 12 stops working.

[0131] The output voltage of the voltage conversion circuit 10 is different, and the voltage signal corresponding to the current collected by the current sampling unit 142 is different. The voltage signal can be expressed as V samp For example, when the output voltage of the voltage conversion circuit 10 is 12Vdc, the voltage signal corresponding to the current collected by the current sampling unit 142 may be V samp1 When the output voltage of the voltage conversion circuit 10 is 24Vdc, the voltage signal corresponding to the current collected by the current sampling unit 142 may be V samp2 .

[0132] The power protection module 14 includes a voltage comparison unit 141 and a current sampling unit 142; the first input end of the voltage comparison unit 141 is connected to the output end of the reference voltage module 13, the second input end of the voltage comparison unit 141 is connected to the output end of the current sampling unit 142, the input end of the current sampling unit 142 is connected to the voltage conversion circuit 10, and the output end of the voltage comparison unit 141 is connected to the control chip 12; the current sampling unit 142 is used to sample the output current of the voltage conversion circuit 10 and convert the output current into a voltage signal; the voltage comparison unit 141 is used to convert the output current into a voltage signal according to the voltage signal and the current limiting reference voltage V ref When the output current of the voltage conversion circuit 10 exceeds the current limit of the target voltage, the trigger control chip 12 stops working. In the process of protecting the voltage conversion circuit 10, the output current of the voltage conversion circuit 10 can be obtained through the current sampling unit 142, so that the voltage corresponding to the actual output current of the voltage conversion circuit 10 and the current limiting reference voltage V ref The comparison result is used to determine whether there is a potential safety hazard in the operation of the voltage conversion circuit 10. When a potential safety hazard may occur in the voltage conversion circuit 10, the control chip 12 is triggered to stop working in time, thereby ensuring the working safety of the voltage conversion circuit 10.

[0133] In a specific embodiment, Fig. 9As shown, the current sampling unit 142 includes an operational amplifier unit 1421 and a filter unit 1422; the first input terminal and the second input terminal of the operational amplifier unit 1421 are connected to the two ends of the sampling resistor in the voltage conversion circuit 10, the output terminal of the operational amplifier unit 1421 is connected to the input terminal of the filter unit 1422, and the output terminal of the filter unit 1422 is connected to the second input terminal of the voltage comparison unit 141;

[0134] The operational amplifier subunit 1421 is used to amplify the voltage difference formed by the output current of the voltage conversion circuit 10 flowing through the sampling resistor;

[0135] The filter subunit 1422 is used to filter the voltage difference amplified and output by the operational amplifier subunit 1421 and input the result as a voltage signal into the voltage comparison unit 141 .

[0136] In the embodiment of the present application, the output current collected by the current sampling unit 142 flowing through the sampling resistor is small, and the output current includes a noise signal. Therefore, when the voltage signal corresponding to the sampling current is compared with the current limiting reference voltage V ref Before the comparison, the operational amplifier unit 1421 is used to amplify the voltage signal corresponding to the output current, and then the filter unit 1422 is used to filter the amplified voltage signal to avoid interference of the noise signal on the voltage signal.

[0137] The operational amplifier subunit 1421 may include only one operational amplifier, or may be composed of one operational amplifier and multiple electronic components. The filter subunit 1422 may be a circuit composed of resistors and capacitors.

[0138] In one embodiment, Fig.10 As shown, the operational amplifier subunit 1421 includes: an operational amplifier U1, a resistor R7, a resistor R8, a resistor R9 and a resistor R10, and a first capacitor C1 and a second capacitor C2; a resistor R7 is arranged between the non-inverting input terminal of the operational amplifier U1 and one end of the sampling resistor, and a resistor R8 is arranged between the inverting input terminal of the operational amplifier U1 and the other end of the sampling resistor; the resistor R9 and the first capacitor C1 are arranged in parallel between the non-inverting input terminal of the operational amplifier U1 and the ground; the resistor R10 and the second capacitor C2 are connected in parallel, one end of the parallel connection is connected to the inverting input terminal of the operational amplifier U1, and the other end of the parallel connection is connected to the output terminal of the operational amplifier U1; the output terminal of the operational amplifier U1 is connected to the filtering subunit 1422.

[0139] The filter subunit 1422 includes a resistor eleven R11 and a third capacitor C3; the first end of the resistor eleven R11 is connected to the output end of the operational amplifier U1, the second end of the resistor eleven R11 is respectively connected to the first end of the third capacitor C3 and the second input end of the voltage comparison unit 141, and the second end of the third capacitor C3 is grounded.

[0140] Among them, the resistance values ​​of resistor 7 R7 and resistor 8 R8 are the same, and the resistance values ​​of resistor 9 R9 and resistor 10 R10 are the same. The input terminals of the operational amplifier U1 are connected to Figure 1 The two ends of the sampling resistor in the voltage conversion circuit 10, that is, the first end of the resistor R8 is connected to the first end of the sampling resistor, and the first end of the resistor R7 is connected to the second end of the sampling resistor. By collecting the output current flowing through the sampling resistor in the voltage conversion circuit 10, the voltage signal at both ends of the sampling resistor can be obtained. Assuming that the voltage comparison unit includes a comparator, the voltage signal can be amplified and filtered, and then input into the same-direction input end of the comparator. The voltage signal input to the same-direction input end of the comparator can be expressed as:

[0141]

[0142] in, represents the resistance value of the sampling resistor in the voltage conversion circuit 10; It represents the current flowing through the sampling resistor of the voltage conversion circuit 10.

[0143] Exemplarily, when the output voltage of the voltage conversion circuit 10 is 12Vdc, the first current limiting reference voltage V ref1 Need to design so When the current is 50A, V ref1 =V samp1 When the output voltage of the voltage conversion circuit 10 is 24Vdc, the second current limiting reference voltage V ref2 Need to design so When the current is 25A, V ref2 =V samp2 .

[0144] The above-mentioned current sampling unit 142 includes an operational amplifier unit 1421 and a filter unit 1422; the first input terminal and the second input terminal of the operational amplifier unit 1421 are connected to the two ends of the sampling resistor in the voltage conversion circuit 10, the output terminal of the operational amplifier unit 1421 is connected to the input terminal of the filter unit 1422, and the output terminal of the filter unit 1422 is connected to the second input terminal of the voltage comparison unit 141; the operational amplifier unit 1421 is used to amplify the voltage difference formed by the output current of the collected voltage conversion circuit 10 flowing through the sampling resistor; the filter unit 1422 is used to filter the voltage difference amplified and output by the operational amplifier unit 1421 and input it as a voltage signal into the voltage comparison unit 141. In the current sampling process, the operational amplifier unit 1421 can be used to ensure that the voltage signal corresponding to the actual output current of the voltage conversion circuit is consistent with the current limiting reference voltage V ref At the same time, the noise signal in the voltage signal corresponding to the actual output current is filtered out by the filter subunit 1422, thereby avoiding the interference of noise on the voltage signal, and preventing the current from instantaneously overshooting or jittering and causing malfunction and causing the control chip 12 to stop working.

[0145] Next, the specific contents of the voltage comparison unit 141 are introduced. Fig.11 As shown, the voltage comparison unit 141 includes a comparator U2 and a third switch subunit 1411, the inverting input terminal of the comparator U2 is connected to the output terminal of the reference voltage module 13, the non-inverting input terminal of the comparator U2 is connected to the output terminal of the current sampling unit 142, the output terminal of the comparator U2 is connected to the first terminal of the third switch subunit 1411, the second terminal of the third switch subunit 1411 is connected to the enable terminal of the control chip 12, and the third terminal of the third switch subunit 1411 is grounded;

[0146] The comparator U2 is used to output a high level when the voltage at the non-inverting input terminal is greater than the voltage at the inverting input terminal;

[0147] The third switch subunit 1411 is in a conducting state when the comparator U2 outputs a high level, and is used to pull down the level of the enable terminal of the control chip 12 to stop the control chip 12 from working.

[0148] In the embodiment of the present application, the output end of the comparator U2 is connected to the enable end of the control chip 12 through the third switch sub-unit 1411. When the enable end is in a low level state, the control chip 12 stops working and the output voltage of the voltage conversion circuit 10 is zero.

[0149] The non-inverting input of comparator U2 is input with the current limiting reference voltage V ref The inverting input terminal inputs the voltage signal corresponding to the actual output current of the voltage conversion circuit 10. The comparator U2 is used to convert the current limiting reference voltage Vref Compare it with the voltage signal corresponding to the actual output current to determine whether the voltage signal corresponding to the actual output current exceeds the current limiting reference voltage V ref If the current limiting reference voltage V ref , comparator U2 outputs a low level; if it exceeds the current limiting reference voltage V ref , comparator U2 outputs a high level.

[0150] When it is determined that the comparator U2 outputs a low-level signal, the third switch subunit 1411 is in the cut-off state, at which time the enable terminal of the control chip 12 is at a high level, and both the control chip 12 and the voltage conversion circuit 10 operate normally. When it is determined that the comparator U2 outputs a high-level signal, the third switch subunit 1411 is in the on state, at which time the enable terminal of the control chip 12 is directly grounded, and the level of the enable terminal is pulled low, so that both the control chip 12 and the voltage conversion circuit 10 stop operating.

[0151] In one embodiment, Fig.12 As shown, the third switch subunit 1411 includes a resistor twelve R12, a resistor thirteen R13 and a first transistor Q3; one end of the resistor twelve R12 is connected to the output end of the comparator U2 and one end of the resistor thirteen R13, the other end of the resistor thirteen R13 is connected to the power supply voltage VCC, the other end of the resistor twelve R12 is connected to the base of the first transistor Q3, the collector of the first transistor Q3 is connected to the enable end of the control chip 12, and the emitter of the first transistor Q3 is grounded; when the comparator U2 outputs a high level, the first transistor Q3 is in an on state; when the comparator U2 outputs a low level, the first transistor Q3 is in an off state.

[0152] Exemplarily, the first current limiting reference voltage V ref1 is the voltage corresponding to 12Vdc, then when the current flowing through the sampling resistor in the voltage conversion circuit 10 is less than 50A, V samp1 Less than V ref1 , the comparator U2 outputs a low level, the first transistor Q3 is turned off and on, the enable terminal level of the control chip 12 is not pulled down, and the voltage conversion circuit 10 works normally. When the current of the sampling resistor is greater than 50A, V samp1 Greater than V ref1 , the comparator U2 outputs a high level, the first transistor Q3 is turned on, the enable terminal level of the control chip 12 is pulled low, and the voltage conversion circuit 10 cannot work normally.

[0153] The second current limiting reference voltage V ref2 is the voltage corresponding to 24Vdc, then when the current flowing through the sampling resistor in the voltage conversion circuit 10 is less than 25A, V samp2 Less than V ref2, the comparator U2 outputs a low level, the first transistor Q3 is turned off and on, the enable pin of the control chip 12 is not pulled low, and the voltage conversion circuit 10 works normally. When the current of the sampling resistor is greater than 25A, V samp2 Greater than V ref2 , the comparator U2 outputs a high level, the first transistor Q3 is turned on, the enable pin of the control chip 12 is pulled low, and the voltage conversion circuit 10 cannot work normally.

[0154] The voltage comparison unit 141 includes a comparator U2 and a third switch subunit 1411. The inverting input terminal of the comparator U2 is connected to the output terminal of the reference voltage module 13, the non-inverting input terminal of the comparator U2 is connected to the output terminal of the current sampling unit 142, the output terminal of the comparator U2 is connected to the first terminal of the third switch subunit 1411, the second terminal of the third switch subunit 1411 is connected to the enable terminal of the control chip 12, and the third terminal of the third switch subunit 1411 is grounded; the comparator U2 is used to output a high level when the voltage at the non-inverting input terminal is greater than the voltage at the inverting input terminal; the third switch subunit 1411 is in a conducting state when the comparator U2 outputs a high level, and is used to pull down the enable terminal level of the control chip 12 to stop the control chip 12 from working. The voltage corresponding to the sampling current is compared with the current limiting reference voltage V by the comparator U2. ref The comparison is performed, and the level signal generated based on the comparison result controls the on and off of the third switch subunit 1411. When the sampling current of the voltage conversion circuit 10 is too large, the enable terminal level of the control chip 12 is timely lowered, thereby ensuring the working safety of the voltage conversion circuit 10.

[0155] It can be seen from the description of the above embodiments that the voltage switching circuit 11 can enable the voltage conversion circuit 10 to output 12Vdc, and can also switch from 12Vdc to 24Vdc. At the same time, during the voltage switching process, the current limit will also switch from 50A to 25A. In this way, the output power of the voltage conversion circuit 10 will not exceed 600W. After exceeding 600W, the control chip 12 and the voltage conversion circuit 10 will stop working. In other words, regardless of whether the output voltage of the voltage conversion circuit 10 is 12Vdc or 24Vdc, it can be determined whether the actual output current of the voltage conversion circuit 10 exceeds the current limit, thereby ensuring the safety of the voltage conversion circuit 10 during operation.

[0156] In the process of protecting the voltage conversion circuit 10, the enable terminal level of the control chip 12 will be pulled down, and the voltage conversion circuit 10 will stop working. In this case, the voltage input from the current sampling unit 142 to the in-phase input terminal of the comparator U2 is 0, the comparator U2 will output a low-level signal, the first transistor Q3 is turned off and turned on, the enable terminal of the control chip 12 is not pulled down, and the voltage conversion circuit 10 continues to work. If the output port output of the voltage conversion circuit 10 is loaded, the voltage conversion circuit 10 still triggers the protection mechanism, so that the voltage conversion circuit 10 will repeatedly stop working and then work again. Then, in order to solve this problem, a self-locking unit 143 is introduced in the above-mentioned power protection module 14 to ensure that the voltage conversion circuit 10 is always in a stopped working state after the control chip 12 stops working.

[0157] In one embodiment, Fig.13 As shown, the power protection module 14 further includes a self-locking unit 143, a first end of the self-locking unit 143 is connected to the power supply voltage VCC, and a second end of the self-locking unit 143 is connected to the voltage comparison unit 141;

[0158] The self-locking unit 143 is used to continuously lock the control chip 12 in a stopped state when the control chip 12 is triggered to stop working.

[0159] Among them, the self-locking unit 143 includes a second transistor Q4, a resistor fourteen R14 and a resistor fifteen R15; the first end of the resistor fourteen R14 and the emitter of the second transistor Q4 are both connected to the power supply voltage VCC, the base of the second transistor Q4 is connected between the resistor fourteen R14 and the resistor fifteen R15, and the other end of the resistor fifteen R15 and the collector of the second transistor Q4 are both connected to the voltage comparison unit 141.

[0160] In the embodiment of the present application, when the voltage at the non-inverting input terminal is less than the voltage at the inverting input terminal and a high level is output, the first transistor Q3 is turned off and turned on, the enable terminal level of the control chip 12 is not pulled down, and the voltage conversion circuit 10 works normally. At this time, the emitter and base of the second transistor Q4 are at the same potential, and the second transistor Q4 is turned off and turned on.

[0161] When the voltage at the in-phase input terminal is greater than the voltage at the inverting input terminal and a low level is output, the first transistor Q3 is turned on, the enable terminal level of the control chip 12 is pulled down, and the voltage conversion circuit 10 stops working. At the same time, the resistor 14 R14 and the resistor 15 R15 divide the power supply voltage VCC, so that the emitter potential of the second transistor Q4 is higher than the base potential, and the second transistor Q4 is turned on. The power supply voltage VCC passes through the second transistor Q4 to the base of the first transistor Q3, so that the first transistor Q3 is continuously turned on, forming a self-locking with the second transistor Q4, so that the enable terminal level of the control chip 12 is continuously pulled down. In this way, after the enable terminal level of the control chip 12 is pulled down, the voltage conversion circuit 10 will remain in a stopped state. The voltage conversion circuit 10 can only resume working after the user restarts.

[0162] The power protection module 14 further includes a self-locking unit 143, a first end of the self-locking unit 143 is connected to the power supply voltage VCC, and a second end of the self-locking unit 143 is connected to the voltage comparison unit 141; the self-locking unit 143 is used to continuously lock the control chip 12 in a stopped state when the control chip 12 is triggered to stop working. By introducing the self-locking unit 143 in the power protection module 14, when the output power of the voltage conversion circuit 10 exceeds the power limit, the control chip 12 can be continuously locked in a stopped state, so that the situation where the voltage conversion circuit 10 repeatedly stops working and then works again can be avoided.

[0163] In one embodiment, an energy storage power supply is further provided. The energy storage power supply includes the voltage switching circuit provided in any one of the embodiments.

[0164] Among them, the energy storage power supply is provided with the above-mentioned voltage switching circuit 11. In this way, when the energy storage power supply is used to power electrical equipment in the RV, the energy storage power supply can flexibly adjust the voltage output by the power interface according to the voltage required by the RV to meet the needs of different types of voltages, thereby solving the problem of poor applicability of the energy storage power supply scenario.

[0165] Of course, this energy storage power supply is not only used in RV power supply scenarios, but can also be used in other electrical equipment, such as household appliances and so on.

[0166] The above content is a further detailed description of the embodiments of the present application in combination with specific / preferred implementation methods, and it cannot be determined that the specific implementation of the embodiments of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the embodiments of the present application belong, without departing from the concept of the embodiments of the present application, it can also make several substitutions or modifications to these described implementation methods, and these substitutions or modifications should be regarded as belonging to the protection scope of the embodiments of the present application. In the description of this specification, the description of the reference terms "an embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the various technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered as the scope recorded in this specification.

[0167] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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, they should be considered to be within the scope of this application.

[0168] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

[0169] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A voltage switching circuit, characterized in that: Applied in a voltage conversion circuit, the voltage switching circuit comprises: a control chip, a reference voltage module connected to the control chip, a power protection module and a voltage signal trigger; the control chip and the reference voltage module are both connected to the voltage conversion circuit and the power protection module, the reference voltage module comprises a reference voltage feedback unit, and the reference voltage feedback unit comprises a first switch subunit and a first voltage dividing subunit; the first end of the first switch subunit is connected to the voltage signal trigger, the second end of the first switch subunit is connected to the first end of the first voltage dividing subunit, and the second end of the first voltage dividing subunit is respectively connected to the control chip and the voltage conversion circuit; The reference voltage module is used to output a feedback reference voltage matching the target voltage to the control chip according to the target voltage signal input through the voltage signal trigger, and output a current limiting reference voltage corresponding to the current limit value of the target voltage to the power protection module; the target voltage is any one of the multiple voltages supported by the voltage conversion circuit; The control chip is used to adjust the output voltage of the voltage conversion circuit to the target voltage according to the feedback reference voltage; The power protection module is used to trigger the control chip to stop working when the output power of the voltage conversion circuit exceeds the power limit value based on the current limiting reference voltage.

2. The voltage switching circuit according to claim 1, characterized in that: The reference voltage module further includes a current limit reference voltage unit; the current limit reference voltage unit is connected between the voltage signal trigger and the power protection module; The current limit reference voltage unit is used to output the current limit reference voltage to the power protection module according to the target voltage signal input on the voltage signal trigger.

3. The voltage switching circuit according to claim 2, characterized in that: The first voltage dividing subunit is used to divide the output voltage of the voltage conversion circuit when the target voltage signal triggered on the voltage signal trigger is at a low level, so as to output a first feedback reference voltage to the control chip when the first switch subunit is in an off state; Furthermore, when the target voltage signal triggered on the voltage signal trigger is at a high level and the first switch subunit is in an on state, the output voltage of the voltage conversion circuit is divided to output a second feedback reference voltage to the control chip.

4. The voltage switching circuit according to claim 3, characterized in that: The first switch subunit includes a first switch tube, and the first voltage divider subunit includes a resistor 1, a resistor 2, and a resistor 3; The gate of the first switch tube is connected to the voltage signal trigger, the drain of the first switch tube is connected to one end of the resistor one, the other end of the resistor one is connected between the resistor two and the resistor three, the other end of the resistor two is respectively connected to the control chip and the voltage conversion circuit, and the other end of the resistor three and the source of the first switch tube are both grounded.

5. The voltage switching circuit according to claim 2, characterized in that: The current limit reference voltage unit includes a second switch subunit and a second voltage divider subunit; the first end of the second switch subunit is connected to the voltage signal trigger, the second end of the second switch subunit is connected to the first end of the second voltage divider subunit, and the second end of the second voltage divider subunit is respectively connected to the power supply voltage and the power protection module; The second voltage dividing subunit is used for dividing the supply voltage when the target voltage signal triggered on the voltage signal trigger is at a low level, so as to output a first current limiting reference voltage to the power protection module when the second switch subunit is in an off state; Furthermore, when the target voltage signal triggered on the voltage signal trigger is at a high level and the second switch subunit is in an on state, the supply voltage is divided to output a second current limiting reference voltage to the power protection module.

6. The voltage switching circuit according to any one of claims 1 to 5, characterized in that: The power protection module includes a voltage comparison unit and a current sampling unit; the first input end of the voltage comparison unit is connected to the output end of the reference voltage module, the second input end of the voltage comparison unit is connected to the output end of the current sampling unit, the input end of the current sampling unit is connected to the voltage conversion circuit, and the output end of the voltage comparison unit is connected to the control chip; The current sampling unit is used to sample the output current of the voltage conversion circuit and convert the output current into a voltage signal; The voltage comparison unit is used to trigger the control chip to stop working when the output current of the voltage conversion circuit exceeds the current limit value of the target voltage according to the voltage signal and the current limiting reference voltage.

7. The voltage switching circuit according to claim 6, characterized in that: The current sampling unit includes an operational amplifier unit and a filter unit; the first input terminal and the second input terminal of the operational amplifier unit are connected to the two ends of the sampling resistor in the voltage conversion circuit, the output terminal of the operational amplifier unit is connected to the input terminal of the filter unit, and the output terminal of the filter unit is connected to the second input terminal of the voltage comparison unit; The operational amplifier subunit is used to amplify the voltage difference formed by the output current in the voltage conversion circuit flowing through the sampling resistor; The filtering subunit is used to filter the voltage difference amplified and output by the operational amplifier subunit and input the filtered voltage as the voltage signal into the voltage comparison unit.

8. The voltage switching circuit according to claim 6, characterized in that: The voltage comparison unit includes a comparator and a third switch subunit, the inverting input terminal of the comparator is connected to the output terminal of the reference voltage module, the non-inverting input terminal of the comparator is connected to the output terminal of the current sampling unit, the output terminal of the comparator is connected to the first terminal of the third switch subunit, the second terminal of the third switch subunit is connected to the enable terminal of the control chip, and the third terminal of the third switch subunit is grounded; The comparator is used to output a high level when the voltage at the non-inverting input terminal is greater than the voltage at the inverting input terminal; The third switch sub-unit is in a conducting state when the comparator outputs a high level, and is used to pull down the level of the enable terminal of the control chip to stop the control chip from working.

9. The voltage switching circuit according to claim 6, characterized in that: The power protection module further comprises a self-locking unit, a first end of the self-locking unit is connected to the power supply voltage, and a second end of the self-locking unit is connected to the voltage comparison unit; The self-locking unit is used to continuously lock the control chip in a stopped working state when the control chip is triggered to stop working.

10. An energy storage power supply, characterized in that: The energy storage power supply comprises the voltage switching circuit described in any one of claims 1-9.

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