Charging control circuit and energy storage power supply thereof

Abstract

The embodiment of the utility model discloses a charging control circuit and an energy storage power supply thereof. The circuit comprises a voltage detection module which is configured to be used for detecting the output voltage of the energy storage equipment and outputting a voltage control signal when the output voltage is smaller than a first preset voltage threshold value; the current detection module is configured to be used for detecting charging current flowing through the energy storage equipment and outputting a current control signal when the charging current is greater than a preset current threshold value; and the control module is connected between the power supply and the energy storage equipment, is also connected with the voltage detection module and the current detection module, and is configured to be switched on in response to the voltage control signal or the current control signal so as to enable the power supply to charge the energy storage equipment. Through the above mode, the embodiment of the utility model can realize load activation type charging control, avoid unnecessary electric quantity loss caused by repeated activation of the energy storage equipment when no-load connection is carried out, improve the actual utilization rate of the energy storage equipment, and prolong the service life of the energy storage equipment.

Description

Technical Field

[0001] This utility model relates to the field of portable energy storage, and in particular to a charging control circuit and its energy storage power supply. Background Technology

[0002] The car fast charger uses the extra power provided by the car's alternator to quickly charge the portable energy storage device. One end connects to the car battery, and the other end connects to the PV charging port of the energy storage device.

[0003] When the car engine is working normally, the battery activates the energy storage device through the car's fast charging and then charges the energy storage device. When the car engine stops working, the battery voltage (when the battery voltage can activate the car's fast charging) continues to activate the energy storage device through the car's fast charging. At this time, the energy storage device is repeatedly activated and turned on and off, and its own power is continuously consumed until the energy storage battery is depleted and shuts down, causing unnecessary losses due to frequent switching. Utility Model Content

[0004] The main technical problem solved by this utility model embodiment is to provide a charging control circuit and its energy storage power supply, which can solve at least some of the problems existing in energy storage devices.

[0005] In a first aspect, this utility model provides a charging control circuit connected between a power supply and an energy storage device, comprising: a voltage detection module configured to detect the output voltage of the energy storage device and output a voltage control signal when the output voltage is less than a first preset voltage threshold; a current detection module configured to detect the charging current flowing through the energy storage device and output a current control signal when the charging current is greater than a preset current threshold; and a control module connected between the power supply and the energy storage device, further connected to the voltage detection module and the current detection module, configured to be turned on in response to the voltage control signal or the current control signal, so that the power supply charges the energy storage device.

[0006] Optionally, the charging control circuit further includes a voltage divider module connected to the energy storage device, which is used to form a voltage divider network with the load when the energy storage device is connected to a load, thereby generating a voltage divider node; the voltage detection module is used to detect the output voltage of the voltage divider node.

[0007] Optionally, the voltage detection module includes a first comparison unit and a buffer unit. The first comparison unit is connected to the voltage divider node and the buffer unit, and the buffer unit is connected to the control module. The first comparison unit is configured to detect the output voltage, output a first signal when the output voltage is less than a first preset voltage threshold, and stop outputting the first signal when the output voltage is greater than the first preset voltage threshold. The buffer unit is configured to charge in response to the first signal and output the voltage control signal, and discharge after stopping receiving the first signal, maintaining the output of the voltage control signal until the voltage of the buffer unit is lower than a preset voltage after discharge.

[0008] Optionally, the first comparison unit includes an eleventh resistor, a twelfth resistor, a thirteenth resistor, a third diode, a fourth diode, and a second comparator; the first end of the eleventh resistor is connected to the voltage divider node, the second end of the eleventh resistor is connected to the anode of the third diode, the anode of the fourth diode, and the inverting input of the second comparator, and the cathode of the third diode is connected to a first voltage source; the non-inverting input of the second comparator is connected to the first end of the twelfth resistor, the second end of the twelfth resistor is connected to a reference voltage source, the output of the second comparator is connected to the first end of the thirteenth resistor and the input of the buffer unit, the second end of the thirteenth resistor is connected to a fourth voltage source, and the cathode of the fourth diode is connected to reference ground.

[0009] Optionally, the buffer unit includes a fourteenth resistor, a third capacitor, and a fifth diode; and the first terminal of the fourteenth resistor, the first terminal of the third capacitor, the anode of the fifth diode, and the output terminal of the first comparison unit are connected, the cathode of the fifth diode is connected to the control module, and the second terminal of the fourteenth resistor and the second terminal of the third capacitor are connected to reference ground.

[0010] Optionally, it also includes a current sampling module, which is connected between the power supply and the energy storage device. The current detection module is used to detect the charging voltage generated by the charging current flowing through the current sampling module, and outputs the current control signal when the charging voltage is greater than a second preset voltage threshold.

[0011] Optionally, the current detection module includes a conversion unit and a second comparison unit. The conversion unit is connected to the current sampling module and the second comparison unit, and the second comparison unit is connected to the control module. The conversion unit is configured to convert the charging current into the charging voltage. The second comparison unit is configured to output the current control signal when the charging voltage is greater than the second preset voltage threshold, and to stop outputting the current control signal when the charging voltage is less than the second preset voltage threshold.

[0012] Optionally, the conversion unit includes a sixth resistor, a seventh resistor, an eighth resistor, a fifteenth resistor, a first capacitor, a second capacitor, and a first operational amplifier; the first end of the seventh resistor is connected to the first end of the current sampling module, the second end of the seventh resistor is connected to the first end of the first capacitor, the first end of the sixth resistor, and the inverting input of the first operational amplifier, and the output of the first operational amplifier is connected to the second end of the sixth resistor, the second end of the first capacitor, and the input of the second comparison unit; the first end of the eighth resistor is connected to the second end of the current sampling module, the second end of the eighth resistor is connected to the first end of the fifteenth resistor, the first end of the second capacitor, and the non-inverting input of the first operational amplifier, and the second end of the fifteenth resistor and the second end of the second capacitor are connected to a second voltage source.

[0013] Optionally, the second comparison unit includes a ninth resistor, a tenth resistor, a second diode, and a first comparator; the non-inverting input of the first comparator is connected to the output of the conversion unit, the inverting input of the first comparator is connected to the first end of the ninth resistor, the second end of the ninth resistor is connected to a reference voltage source, the output of the first comparator, the first end of the tenth resistor, and the anode of the second diode are connected, the second end of the tenth resistor is connected to a third voltage source, and the cathode of the second diode is connected to the control module.

[0014] In a first aspect, the present invention provides an energy storage power supply, comprising: a power supply; a voltage conversion circuit; and a charging control circuit as described in the first aspect, connected to the power supply, the voltage conversion module, and the energy storage device.

[0015] The beneficial effects of this utility model embodiment are: unlike the prior art, this utility model embodiment can realize load-activated charging control, avoid unnecessary power loss caused by repeated activation of energy storage devices when no load is connected, improve the actual utilization rate of energy storage devices, and extend the service life of energy storage devices. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1 This is a schematic diagram showing the connection between the energy storage device and the car battery;

[0018] Figure 2 This is a schematic diagram of the structure of a charging control circuit provided in an embodiment of this application;

[0019] Figure 3 This is a schematic diagram of another charging control circuit provided in the embodiments of this application;

[0020] Figure 4 This is a circuit diagram of a charging control circuit provided in an embodiment of this application. Detailed Implementation

[0021] To facilitate understanding of this utility model, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "connected" to another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this specification are for illustrative purposes only.

[0022] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0023] Reference Figure 2 , Figure 2 This is a schematic diagram of a charging control circuit provided in an embodiment of this application. Figure 2 The image shows a charging control circuit 10, which includes a voltage detection module 110, a current detection module 120, and a control module 130. The charging control circuit 10 is connected between the power supply 20 and the energy storage device 30, and in conjunction with... Figure 1 In the application scenario shown, the power supply 20 can be a car battery, and the energy storage device 30 can be a portable energy storage power supply.

[0024] like Figure 1 As shown, the voltage conversion circuit 40 (i.e., fast charging) uses the additional power provided by the car's alternator to quickly charge the energy storage device 30 (i.e., portable energy storage). One end of the fast charging circuit is connected to the power supply 20 (i.e., the car battery), and the other end is connected to the PV charging port of the energy storage device. In the prior art, when the car engine is working normally, the battery activates the energy storage device through the fast charging circuit and then charges the energy storage device; when the car engine stops working, the battery voltage (when the battery voltage can activate the fast charging circuit) still continuously activates the energy storage device through the fast charging circuit. At this time, the energy storage device is repeatedly activated to turn on and off, and its own power is continuously consumed until the energy storage battery is depleted and it shuts down, causing unnecessary losses due to frequent switching.

[0025] To address the aforementioned issues, this embodiment provides a load-activated low-power circuit. The energy storage device is only charged when its load power exceeds a set power. When the power does not reach the set value, the energy storage device is not activated and is not charged. This allows the charging of the energy storage device to be controlled by the magnitude of the connected load power, thereby improving the actual utilization rate of the energy storage device and avoiding unnecessary losses caused by frequent switching.

[0026] In this embodiment, the voltage detection module 110 is configured to detect the output voltage of the energy storage device 30 and output a voltage control signal when the output voltage is less than a first preset voltage threshold. Specifically, when the energy storage device 30 is connected to a load, the output voltage of the energy storage device 30 changes with the size of the load. As an example and not a limitation, when no load is connected, the output voltage of the energy storage device 30 is approximately 3.3V; when a small load is connected, the output voltage is approximately 1.5V; and when a large load is connected, the output voltage will further decrease. The voltage detection module 110 determines the connection status of the load by detecting changes in the output voltage. When the output voltage is detected to be less than the first preset voltage threshold (e.g., 2V), it indicates that the energy storage device 30 is connected to a load. At this time, the voltage detection module 110 outputs a voltage control signal to trigger charging control.

[0027] The current detection module 120 is configured to detect the charging current flowing through the energy storage device 30 and output a current control signal when the charging current exceeds a preset current threshold. When the energy storage device 30 is connected to a large load, the charging current flowing through it will increase accordingly. The current detection module 120 determines the load condition by detecting the magnitude of the charging current, and outputs a current control signal when the charging current exceeds the preset current threshold to ensure continuous charging of the energy storage device 30 under heavy load conditions.

[0028] The control module 130 is connected between the power supply 20 and the energy storage device 30, and is also connected to the voltage detection module 110 and the current detection module 120. The control module 130 is configured to turn on in response to a voltage control signal or a current control signal, so that the power supply 20 charges the energy storage device 30. The control module 130 uses an "OR" logic relationship, that is, as long as it receives either the voltage control signal or the current control signal, the control module 130 will turn on and start the charging process.

[0029] The working process of the charging control circuit 10 in this embodiment can be divided into the following four cases:

[0030] In the first scenario, when the energy storage device 30 is not connected to a load, for example, the output voltage of the energy storage device 30 is approximately 3.3V, which is greater than a first preset voltage threshold (e.g., 2V). Therefore, the voltage detection module 110 does not output a voltage control signal. Simultaneously, since no load is connected, the circuit does not form a closed loop, and the charging current is 0, less than a preset current threshold. Therefore, the current detection module 120 does not output a current control signal. Consequently, the control module 130 is not activated, and the power supply 20 does not charge the energy storage device 30, thus avoiding power loss caused by repeated activation of the energy storage device 30.

[0031] In the second scenario, when the energy storage device 30 is connected to a small load, for example, the output voltage of the energy storage device 30 drops to approximately 1.5V, which is less than a first preset voltage threshold (e.g., 2V), and the voltage detection module 110 outputs a voltage control signal. At this time, the load is small, and the charging current is close to 0, which is less than a preset current threshold, so the current detection module 120 does not output a current control signal. However, since the control module 130 uses "OR" logic, it turns on immediately upon receiving the voltage control signal, and the power supply 20 begins to charge the energy storage device 30.

[0032] In the third scenario, when the energy storage device 30 is connected to a large load, the voltage supplied to the load exceeds the first preset voltage threshold (e.g., 2V). The voltage detection module 110 may not output a voltage control signal; however, due to the large load, the charging current increases and exceeds the preset current threshold, causing the current detection module 120 to output a current control signal. Upon receiving the current control signal, the control module 130 is activated, and the power supply 20 continuously charges the energy storage device 30.

[0033] In the fourth scenario, when the energy storage device 30 is fully charged and the load decreases to near zero, for example, the output voltage of the energy storage device 30 rises back to approximately 3V, which is greater than a first preset voltage threshold (e.g., 2V), and the voltage detection module 110 does not output a voltage control signal; simultaneously, the charging current approaches zero and is less than a preset current threshold, and the current detection module 120 does not output a current control signal. Therefore, the control module 130 is not turned on, and the power supply 20 stops charging the energy storage device 30.

[0034] Reference Figure 3 , Figure 3 This is a schematic diagram of another charging control circuit provided in an embodiment of this application. Figure 3 The image shows a charging control circuit 10, which includes a voltage detection module 110, a current detection module 120, a control module 130, a voltage divider module 140, and a current sampling module 150. The charging control circuit 10 is connected between the power supply 20 and the energy storage device 30, and in conjunction with... Figure 1 In the application scenario shown, the power supply 20 can be a car battery, and the energy storage device 30 can be a portable energy storage power supply.

[0035] Unlike the charging control circuit shown in the above embodiments, in this embodiment, the charging control circuit 10 adds a voltage divider module 140 and a current sampling module 150, further optimizing the load detection and current monitoring functions.

[0036] The voltage divider module 140 is connected to the energy storage device 30 and is used to form a voltage divider network with the load when the energy storage device 30 is connected to a load, generating a voltage divider node. By way of example and not limitation, the voltage divider module 140 can consist of a diode D1 and a resistor R1. One end of the resistor R1 is connected to the output terminal Vout+ of the energy storage device 30, and the other end is connected to a stable 3.3V reference power supply through the diode D1. When the energy storage device 30 is not connected to a load, the voltage at the voltage divider node (between Vout+ and Vout-) is approximately 3.3V; when a small load is connected, the voltage drops to approximately 1.5V due to the voltage divider effect; when a large load is connected, the voltage drops further. By detecting the voltage changes at the voltage divider node, the voltage detection module 110 can accurately determine the connection status of the load.

[0037] The voltage detection module 110 is connected to the voltage divider module 140 and is configured to detect the output voltage of the voltage divider node. When the output voltage is less than a first preset voltage threshold (e.g., 2V), the module outputs a voltage control signal. The voltage detection module 110 determines the load connection status by comparing the voltage of the voltage divider node with the preset threshold. When the output voltage is detected to be less than the first preset voltage threshold, it indicates that the energy storage device 30 is connected to a load. At this time, the voltage detection module 110 outputs a voltage control signal to trigger charging control.

[0038] In some embodiments, the voltage detection module 110 includes a first comparison unit and a buffer unit. The first comparison unit is connected to a voltage divider node and the buffer unit, and the buffer unit is connected to a control module. The first comparison unit is configured to detect the output voltage, output a first signal when the output voltage is less than a first preset voltage threshold, and stop outputting the first signal when the output voltage is greater than the first preset voltage threshold. The buffer unit is configured to charge in response to the first signal and output a voltage control signal; and discharge after stopping receiving the first signal, maintaining the output of the voltage control signal until the voltage of the buffer unit is lower than a preset voltage after discharge.

[0039] The current sampling module 150 is connected between the power supply 20 and the energy storage device 30 to sample the current flowing through the charging path. By way of example and not limitation, the current sampling module 150 can consist of a precision small resistor R_Current, which generates a voltage drop proportional to the current across its terminals when the charging current flows through it. This voltage drop is transmitted as a charging voltage signal to the current detection module 120 for determining the current magnitude.

[0040] In some embodiments, the current detection module 120 includes a conversion unit and a second comparison unit. The conversion unit is connected to the current sampling module and the second comparison unit, and the second comparison unit is connected to the control module. The conversion unit is configured to convert the charging current into a charging voltage. The second comparison unit is configured to output a current control signal when the charging voltage is greater than a second preset voltage threshold, and to stop outputting the current control signal when the charging voltage is less than the second preset voltage threshold.

[0041] The current detection module 120 is connected to the current sampling module 150 and is used to detect the charging voltage generated by the charging current flowing through the current sampling module 150. When the charging voltage is greater than a second preset voltage threshold, it outputs a current control signal. Specifically, the current detection module 120 may include an operational amplifier and a comparator. The operational amplifier amplifies the small voltage difference across the current sampling module 150, and the comparator compares the amplified voltage with the second preset voltage threshold. When the charging voltage is greater than the second preset voltage threshold, it indicates that the charging current is large. At this time, the current detection module 120 outputs a current control signal to ensure continuous charging of the energy storage device 30 under heavy load conditions.

[0042] Control module 130 is connected between power supply 20 and energy storage device 30, and is also connected to voltage detection module 110 and current detection module 120. Control module 130 is configured to turn on in response to a voltage control signal or a current control signal, so that power supply 20 charges energy storage device 30. By way of example and not limitation, control module 130 may include two series-connected switches Q1 and Q2, which turn on when either a voltage control signal or a current control signal is received, establishing a charging path from power supply 20 to energy storage device 30.

[0043] The working process of the charging control circuit 10 can be divided into the following four cases:

[0044] In the first scenario, when the energy storage device 30 is not connected to a load: the voltage at the voltage divider node is approximately 3.3V, which is greater than the first preset voltage threshold (e.g., 2V), so the voltage detection module 110 does not output a voltage control signal. Simultaneously, because there is no load connected, the circuit does not form a closed loop, the charging current flowing through the current sampling module 150 is 0, and the resulting charging voltage is less than the second preset voltage threshold, so the current detection module 120 does not output a current control signal. Therefore, the control module 130 is not turned on, and the power supply 20 will not charge the energy storage device 30, avoiding power loss caused by repeated activation of the energy storage device 30.

[0045] In the second scenario, when the energy storage device 30 is connected to a small load: due to the voltage divider network formed by the voltage divider module 140 and the load, the voltage at the voltage divider node drops to approximately 1.5V, which is less than the first preset voltage threshold (e.g., 2V). The voltage detection module 110 then outputs a voltage control signal. At this time, the load is small, and the charging current flowing through the current sampling module 150 is close to zero, resulting in a charging voltage less than the second preset voltage threshold. Therefore, the current detection module 120 does not output a current control signal. However, because the control module 130 uses "OR" logic, it conducts immediately upon receiving the voltage control signal, and the power supply 20 begins charging the energy storage device 30.

[0046] In the third scenario, when the energy storage device 30 is connected to a large load: the voltage received by the load is lower, which may cause the voltage at the voltage divider node to exceed the first preset voltage threshold (e.g., 2V). The voltage detection module 110 may not output a voltage control signal. However, due to the larger load, the charging current flowing through the current sampling module 150 increases, resulting in a charging voltage exceeding the second preset voltage threshold. The current detection module 120 then outputs a current control signal. Upon receiving the current control signal, the control module 130 is activated, and the power supply 20 continuously charges the energy storage device 30.

[0047] In the fourth scenario, when the energy storage device 30 is fully charged and the load decreases to near zero: the voltage at the voltage divider node rises back to approximately 3V, which is greater than the first preset voltage threshold (e.g., 2V), and the voltage detection module 110 does not output a voltage control signal; simultaneously, the charging current approaches zero, and the charging voltage generated by the current sampling module 150 is less than the second preset voltage threshold, so the current detection module 120 does not output a current control signal. Therefore, the control module 130 is not turned on, and the power supply 20 stops charging the energy storage device 30.

[0048] The voltage divider module 140 forms a voltage divider network with the connected load in the charging control circuit 10, accurately reflecting the connection status of the load and providing a reliable basis for judgment by the voltage detection module 110. The current sampling module 150 provides accurate current detection capability, providing charging current information to the current detection module 120 by measuring the current in the charging path, ensuring continuous charging under heavy load conditions.

[0049] Through the coordinated operation of the voltage divider module 140 and the current sampling module 150, the charging control circuit 10 achieves more accurate load detection and current monitoring, and can make correct charging decisions under different load conditions. This effectively avoids the power loss caused by repeated activation of the energy storage device 30 when there is no load connection, improves the actual utilization rate of the energy storage device 30, and extends the service life of the energy storage device 30.

[0050] Reference Figure 4 , Figure 4 This is a circuit diagram of a charging control circuit provided in an embodiment of this application. Figure 4 The complete circuit structure of the charging control circuit 10 is presented in detail, including a voltage detection module 110, a current detection module 120, a control module 130, a voltage divider module 140, and a current sampling module 150. The charging control circuit 10 is connected between the power supply (battery + in the figure) and the energy storage device 30. The power supply can be a car battery, and the energy storage device 30 can achieve charging control through the voltage conversion circuit 40.

[0051] The voltage divider module 140, consisting of diode D1 and resistor R1, is connected between the first voltage source (3.3V) and the output terminal Vout+ of the energy storage device 30. The first end of resistor R1 is connected to the output terminal Vout+ of the energy storage device 30, and the second end of resistor R1 is connected to the anode of diode D1. The cathode of diode D1 is connected to the first voltage source. The voltage divider module 140 and the load connected to the energy storage device 30 (R_Load in the figure) together form a voltage divider network, generating the voltage divider node Vout+. When the energy storage device 30 is not connected to a load, the voltage at the voltage divider node is approximately 3.3V; when a small load is connected, the voltage drops to approximately 1.5V due to the voltage divider effect; when a large load is connected, the voltage drops further.

[0052] The voltage detection module 110 includes a first comparison unit 111 and a buffer unit 112. The first comparison unit 111 includes an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a third diode D3, a fourth diode D4, and a second comparator COMP2. The first terminal of the eleventh resistor R11 is connected to the voltage divider node Vout+, and the second terminal of the eleventh resistor R11 is connected to the anode of the third diode D3, the anode of the fourth diode D4, and the inverting input terminal of the second comparator COMP2. The cathode of the third diode D3 is connected to a 3.3V voltage source. The non-inverting input terminal of the second comparator COMP2 is connected to a reference voltage source DC_2V through the twelfth resistor R12. The output terminal of the second comparator COMP2 is connected to the first terminal of the thirteenth resistor R13 and the input terminal of the buffer unit 112. The cathode of the fourth diode D4 is connected to reference ground GND, and the terminal of the thirteenth resistor R13 is connected to a fourth voltage source (V4). The thirteenth resistor R13 acts as a pull-up resistor for level adaptation.

[0053] The buffer unit 112 includes a fourteenth resistor R14, a third capacitor C3, and a fifth diode D5. The first terminal of the fourteenth resistor R14 is connected to the first terminal of the third capacitor C3, the anode of the fifth diode D5, and the output terminal of the second comparator COMP2. The cathode of the fifth diode D5 is connected to the SW signal terminal of the control module 130. The second terminals of the fourteenth resistor R14 and the third capacitor C3 are connected to reference ground GND. The function of the buffer unit 112 is to charge the third capacitor C3 in response to the signal output by the second comparator COMP2 and output a voltage control signal; and to discharge the third capacitor C3 after stopping receiving the signal from the second comparator COMP2. During this discharge process, the output of the voltage control signal is maintained until the voltage of the third capacitor C3 is lower than a preset voltage after discharge.

[0054] The current sampling module 150 consists of a resistor R_Current, which is connected between the negative terminal Vout- of the energy storage device 30 and the reference ground GND. When the charging current flows through R_Current, a voltage drop proportional to the current is generated across R_Current, which is used by the current detection module 120 to detect the magnitude of the charging current.

[0055] It should be noted that the resistor R_Current is a precise small resistor that does not change with the external load. It is usually designed to have the smallest possible resistance value so as to accurately measure the charging current without affecting the main circuit.

[0056] The current detection module 120 includes a conversion unit 121 and a second comparison unit 122. The conversion unit 121 includes a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a fifteenth resistor R15, a first capacitor C1, a second capacitor C2, and a first operational amplifier U1. The first terminal of the seventh resistor R7 is connected to the I_Out+ terminal of the current sampling module 150. The second terminal of the seventh resistor R7 is connected to the first terminal of the first capacitor C1, the first terminal of the sixth resistor R6, and the inverting input terminal of the first operational amplifier U1. The output terminal V_Out of the first operational amplifier U1 is connected to the second terminal of the sixth resistor R6, the second terminal of the first capacitor C1, and the input terminal of the second comparison unit 122. The first terminal of the eighth resistor R8 is connected to the I_Out- terminal of the current sampling module 150. The second terminal of the eighth resistor R8 is connected to the first terminal of the fifteenth resistor R15, the first terminal of the second capacitor C2, and the non-inverting input terminal of the first operational amplifier U1. The second terminal of the fifteenth resistor R15 and the second terminal of the second capacitor C2 are connected to a second voltage source (+0.8V). The function of the conversion unit 121 is to convert the charging current into the charging voltage V_Out for use by the second comparison unit 122.

[0057] The second comparator unit 122 includes a ninth resistor R9, a tenth resistor R10, a second diode D2, and a first comparator COMP1. The non-inverting input of the first comparator COMP1 is connected to the output V_Out of the first operational amplifier U1. The inverting input of the first comparator COMP1 is connected to the first terminal of the ninth resistor R9, and the second terminal of the ninth resistor R9 is connected to a 2V reference voltage source DC_2V. The output G1 of the first comparator COMP1 is connected to the first terminal of the tenth resistor R10 and the anode of the second diode D2. The second terminal of the tenth resistor R10 is connected to a third voltage source (V3), and the cathode of the second diode D2 is connected to the SW signal terminal of the control module 130. The function of the second comparator unit 122 is to output a current control signal when the charging voltage V_Out is greater than a second preset voltage threshold, and to stop outputting the current control signal when the charging voltage V_Out is less than the second preset voltage threshold.

[0058] In this embodiment of the application, the second preset voltage threshold is 2V.

[0059] The control module 130 is connected between the battery + and the energy storage device 30, and consists of a first switch Q1, a second switch Q2, and multiple related resistors R2-R5. The source of the first switch Q1 is connected to the battery +, the gate of the first switch Q1 is connected to the collector of the second switch Q2 through resistor R3, and the drain of the first switch Q1 is connected to the voltage conversion circuit 40. The base of the second switch Q2 is connected to the first end of resistor R5 and the first end of resistor R4, and the second end of resistor R5 and the emitter of the second switch Q2 are connected to reference ground GND. The second end of resistor R4 is the SW signal terminal of the control module 130, which is connected to the cathode of the fifth diode D5 of the voltage detection module 110 and the cathode of the second diode D2 of the current detection module 120. When a voltage control signal or a current control signal is received, the SW signal terminal becomes high, the second switch Q2 turns on, and then the first switch Q1 turns on, establishing a charging path from the battery + to the energy storage device 30, causing the voltage conversion circuit 40 to start working and charging the energy storage device 30.

[0060] The working process of the charging control circuit 10 can be divided into the following four cases:

[0061] In the first scenario, when the energy storage device 30 is not connected to a load: the voltage at the voltage divider node is approximately 3.3V, which is greater than the first preset voltage threshold. The voltage at the inverting input of the second comparator COMP2 is higher than the voltage at the non-inverting input, resulting in a low-level output. The buffer unit 112 does not generate a voltage control signal. Simultaneously, because no load is connected, the circuit does not form a closed loop, and the charging current flowing through resistor R_Current is zero. The charging voltage V_Out output by the first operational amplifier U1 is approximately 0.8V, which is less than the second preset voltage threshold. The first comparator COMP1 outputs a low level and does not generate a current control signal. Therefore, the SW signal terminal of the control module 130 is at a low level, the first switch Q1 and the second switch Q2 are not conducting, and the power supply will not charge the energy storage device 30.

[0062] In this embodiment of the application, the first preset voltage threshold is 2V.

[0063] In the second scenario, when the energy storage device 30 is connected to a small load: due to the voltage divider network, the voltage at the voltage divider node drops to approximately 1.5V, which is less than the first preset voltage threshold. The voltage at the non-inverting input of the second comparator COMP2 is higher than that at the inverting input, resulting in a high-level first signal output. The third capacitor C3 of the buffer unit 112 charges and generates a voltage control signal, the fifth diode D5 conducts, and the SW signal terminal becomes high. At this time, the current is small, and the charging voltage V_Out output by the first operational amplifier U1 is approximately 0.8V, which is less than the second preset voltage threshold. The first comparator COMP1 outputs a low level and does not generate a current control signal. However, since the SW signal terminal has already become high due to the voltage control signal, the second switch Q2 and the first switch Q1 conduct, and the power supply begins to charge the energy storage device 30.

[0064] In the third scenario, when the energy storage device 30 is connected to a large load: the voltage received by the load is lower, and the voltage at the voltage divider node may change. However, the connected load has formed a current loop, increasing the charging current flowing through resistor R_Current. The first operational amplifier U1 amplifies the voltage across resistor R_Current, and its output V_Out is greater than the second preset voltage threshold. The voltage at the non-inverting input of the first comparator COMP1 is higher than that at the inverting input, resulting in a high-level output signal, i.e., the current control signal. The second diode D2 conducts, and the SW signal remains high, ensuring that the first switch Q1 and the second switch Q2 remain continuously conducting. Even if the output state of the second comparator COMP2 changes due to the voltage change at the voltage divider node, the third capacitor C3 in the buffer unit 112 will slowly discharge, maintaining the output of the current control signal for a period of time until the output of the first comparator COMP1 stabilizes, thus ensuring that the charging process is not interrupted.

[0065] In the fourth scenario, when the energy storage device 30 is fully charged and the load decreases to near zero: the voltage at the voltage divider node rises back to approximately 3V, exceeding the first preset voltage threshold. The second comparator COMP2 outputs a low level, and the third capacitor C3 of the buffer unit 112 discharges, ultimately ceasing to output a voltage control signal. Simultaneously, the charging current approaches zero, and the charging voltage V_Out output by the first operational amplifier U1 drops to approximately 0.8V, less than the second preset voltage threshold. The first comparator COMP1 outputs a low level and does not generate a current control signal. Therefore, the SW signal terminal of the control module 130 becomes low, the first switch Q1 and the second switch Q2 are not turned on, and the power supply stops charging the energy storage device 30.

[0066] Unlike existing technologies, the charging control circuit provided in this application implements intelligent charging control based on load conditions, solving the problem of power loss caused by repeated activation of energy storage devices when no load is connected, and effectively improving the utilization efficiency and lifespan of energy storage devices. The dual protection mechanism of voltage detection and current detection, coupled with the smooth transition function of the buffer unit, ensures the stability and reliability of the charging process, making it suitable for various portable energy storage application scenarios.

[0067] Based on the charging control circuit provided in any of the above embodiments, this application also provides an energy storage power supply, which includes a power supply, a voltage conversion circuit, and a charging control circuit as described in any of the above embodiments, wherein the charging control circuit is connected to the power supply, the voltage conversion module, and the energy storage device.

[0068] It should be noted that while the preferred embodiments of this utility model are provided in the specification and accompanying drawings, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are not intended to impose additional limitations on the content of this utility model; their purpose is to provide a more thorough and comprehensive understanding of the disclosure of this utility model. Furthermore, the above-described technical features can be combined with each other to form various embodiments not listed above, all of which are considered to be within the scope of this utility model specification. Moreover, those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A charging control circuit, connected between a power supply and an energy storage device, characterized in that, include: A voltage detection module is configured to detect the output voltage of the energy storage device and output a voltage control signal when the output voltage is less than a first preset voltage threshold. The current detection module is configured to detect the charging current flowing through the energy storage device and output a current control signal when the charging current is greater than a preset current threshold. The control module connected between the power supply and the energy storage device is also connected to the voltage detection module and the current detection module, and is configured to be turned on in response to the voltage control signal or the current control signal so that the power supply charges the energy storage device.

2. The circuit according to claim 1, characterized in that, It also includes a voltage divider module, which is connected to the energy storage device and is used to form a voltage divider network with the load when the energy storage device is connected to the load, thereby generating voltage divider nodes. The voltage detection module is used to detect the output voltage of the voltage divider node.

3. The circuit according to claim 2, characterized in that, The voltage detection module includes a first comparison unit and a buffer unit. The first comparison unit is connected to the voltage divider node and the buffer unit, and the buffer unit is connected to the control module. The first comparison unit is configured to detect the output voltage and output a first signal when the output voltage is less than the first preset voltage threshold. And when the output voltage is greater than the first preset voltage threshold, the output of the first signal is stopped; The buffer unit is configured to charge in response to the first signal and output the voltage control signal; And after stopping receiving the first signal, discharge is performed to maintain the output of the voltage control signal until the voltage of the buffer unit is discharged below a preset voltage.

4. The circuit according to claim 3, characterized in that, The first comparison unit includes an eleventh resistor, a twelfth resistor, a thirteenth resistor, a third diode, a fourth diode, and a second comparator; The first end of the eleventh resistor is connected to the voltage divider node, the second end of the eleventh resistor is connected to the anode of the third diode, the anode of the fourth diode and the inverting input of the second comparator, and the cathode of the third diode is connected to the first voltage source. The non-inverting input of the second comparator is connected to the first end of the twelfth resistor, the second end of the twelfth resistor is connected to a reference voltage source, the output of the second comparator is connected to the first end of the thirteenth resistor and the input of the buffer unit, the second end of the thirteenth resistor is connected to a fourth voltage source, and the cathode of the fourth diode is connected to reference ground.

5. The circuit according to claim 3, characterized in that, The buffer unit includes a fourteenth resistor, a third capacitor, and a fifth diode; The first terminal of the fourteenth resistor is connected to the first terminal of the third capacitor, the anode of the fifth diode, and the output terminal of the first comparator unit. The cathode of the fifth diode is connected to the control module. The second terminal of the fourteenth resistor and the second terminal of the third capacitor are connected to reference ground.

6. The circuit according to claim 1, characterized in that, It also includes a current sampling module, which is connected between the power supply and the energy storage device. The current detection module is used to detect the charging voltage generated by the charging current flowing through the current sampling module, and outputs the current control signal when the charging voltage is greater than a second preset voltage threshold.

7. The circuit according to claim 6, characterized in that, The current detection module includes a conversion unit and a second comparison unit. The conversion unit is connected to the current sampling module and the second comparison unit, and the second comparison unit is connected to the control module. The conversion unit is configured to convert the charging current into the charging voltage; The second comparison unit is configured to output the current control signal when the charging voltage is greater than the second preset voltage threshold. And when the charging voltage is less than the second preset voltage threshold, the output of the current control signal is stopped.

8. The circuit according to claim 7, characterized in that, The conversion unit includes a sixth resistor, a seventh resistor, an eighth resistor, a fifteenth resistor, a first capacitor, a second capacitor, and a first operational amplifier; The first end of the seventh resistor is connected to the first end of the current sampling module, the second end of the seventh resistor is connected to the first end of the first capacitor, the first end of the sixth resistor and the inverting input of the first operational amplifier, and the output of the first operational amplifier is connected to the second end of the sixth resistor, the second end of the first capacitor and the input of the second comparison unit. The first end of the eighth resistor is connected to the second end of the current sampling module. The second end of the eighth resistor is connected to the first end of the fifteenth resistor, the first end of the second capacitor, and the non-inverting input of the first operational amplifier. The second end of the fifteenth resistor and the second end of the second capacitor are connected to the second voltage source.

9. The circuit according to claim 7, characterized in that, The second comparison unit includes a ninth resistor, a tenth resistor, a second diode, and a first comparator; The non-inverting input of the first comparator is connected to the output of the conversion unit. The inverting input of the first comparator is connected to the first end of the ninth resistor. The second end of the ninth resistor is connected to a reference voltage source. The output of the first comparator is connected to the first end of the tenth resistor and the anode of the second diode. The second end of the tenth resistor is connected to a third voltage source. The cathode of the second diode is connected to the control module.

10. An energy storage power source, characterized in that, include: Power supply; Voltage conversion circuit; as well as The charging control circuit as described in any one of claims 1-9 is connected to the power supply, the voltage conversion module, and the energy storage device.

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