Charging control circuit, optical storage system, photovoltaic system and energy storage system

Abstract

The invention relates to a charging control circuit, a light storage system, a photovoltaic system and an energy storage system. The charging control circuit comprises a current detection module and a switch module, a first end of the current detection module and a first end of the switch module are connected with a photovoltaic panel, a second end of the switch module is connected with a load circuit, the second end of the current detection module is grounded, and the current detection module comprises a thermistor; and the switch module is used for conducting a path between the photovoltaic panel and the load circuit and controlling the photovoltaic panel to charge the load circuit under the condition that the output voltage or the output current of the photovoltaic panel meets the starting condition. By adopting the charging control circuit, the starting time can be accurately controlled.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic power generation technology, and in particular to a charging control circuit, a photovoltaic storage system, a photovoltaic system and an energy storage system. Background Art

[0002] Typically, a charging control circuit used to control a photovoltaic panel to supply power to a load circuit is shut down at night to avoid power consumption and restarted after sunrise.

[0003] However, due to the power consumption of the charging control circuit itself, the startup time is critical. If the startup is too early, the output power of the photovoltaic panel cannot meet the power consumption of the power generation system itself, and the charging control circuit will consume the power of the battery or external power grid in the system due to insufficient power supply from the photovoltaic panel. If the startup is too late, part of the output energy of the photovoltaic panel will be wasted.

[0004] Therefore, there is an urgent need for a charging control circuit that can accurately control the startup time. Summary of the invention

[0005] Based on this, it is necessary to provide a charging control circuit, a photo-storage system, a photovoltaic system and an energy storage system to accurately control the start-up time in response to the above technical problems.

[0006] In a first aspect, the present application provides a charging control circuit, the charging control circuit comprising: a current detection module and a switch module, wherein a first end of the current detection module and a first end of the switch module are both connected to a photovoltaic panel, a second end of the switch module is connected to a load circuit, a second end of the current detection module is grounded, and the current detection module comprises a thermistor;

[0007] The switch module is used to connect the path between the photovoltaic panel and the load circuit when the output voltage or output current of the photovoltaic panel meets the starting conditions, and control the photovoltaic panel to charge the load circuit.

[0008] In one of the embodiments, the current detection module further includes a power consumption suppression unit, a first end of the power consumption suppression unit is connected to the thermistor, and a second end of the power consumption suppression unit is grounded;

[0009] The power consumption suppression unit is used to close the connection between the thermistor and the ground when the output voltage or output current of the photovoltaic panel meets the start-up condition, so as to suppress the power loss of the thermistor.

[0010] In one of the embodiments, the power consumption suppression unit includes a first switch tube and a voltage stabilizing subunit;

[0011] The first end of the voltage stabilizing subunit is respectively connected to the first end of the thermistor, the photovoltaic panel, and the switch module, the drain of the first switch tube is connected to the second end of the thermistor, the gate of the first switch tube is connected to the second end of the voltage stabilizing subunit, and the source of the first switch tube is grounded.

[0012] In one of the embodiments, the voltage stabilizing subunit includes a resistor 1, a resistor 2 and a first diode;

[0013] The first end of resistor one is connected to the first end of the thermistor, the photovoltaic panel, and the switch module respectively; the second end of resistor one, the first end of resistor two, and the cathode of the first diode are all connected to the gate of the first switch tube; the second end of resistor two and the anode of the first diode are all grounded.

[0014] In one of the embodiments, the charging control circuit further includes a voltage control module, a first end of the voltage control module is respectively connected to the photovoltaic panel, the thermistor, and the switch module, and a second end of the voltage control module is connected to the power consumption suppression unit;

[0015] The voltage control module is used to send a voltage control signal to the power consumption suppression unit when the output voltage or output current of the photovoltaic panel meets the start-up condition.

[0016] In one embodiment, the voltage control module includes: a second switch tube, a third resistor, a fourth resistor, a second diode and a third diode;

[0017] The cathode of the second diode is connected to the photovoltaic panel, the thermistor, and the switch module, the anode of the second diode is connected to the first end of resistor three, the second end of resistor three is respectively connected to the first end of resistor four, the cathode of the third diode, and the gate of the second switch tube, the drain of the second switch tube is connected to the power consumption suppression unit, and the second end of resistor four, the anode of the third diode, and the source of the second switch tube are all grounded.

[0018] In one embodiment, the current detection module further includes a relay, a first end of the relay is connected to the thermistor, a second end of the relay is connected to the control module in the load circuit, and a third end of the relay is grounded;

[0019] The control module is used to control the relay to close when the output voltage or output current of the photovoltaic panel does not meet the starting condition; and to control the relay to open when the output voltage or output current of the photovoltaic panel meets the starting condition.

[0020] In one embodiment, the charging control circuit further includes a backfeed protection module, a first end of the backfeed protection module is respectively connected to the photovoltaic panel and the thermistor, and a second end of the backfeed protection module is connected to the switch module;

[0021] The backfeed protection module is used to block the current in the load circuit from flowing to the photovoltaic panel.

[0022] In one embodiment, the backfeed protection module includes a fourth diode or a third switch tube.

[0023] In a second aspect, the present application further provides a photovoltaic storage system, which includes a photovoltaic panel, a load circuit and a charging control circuit according to any one of the first aspects.

[0024] In a third aspect, the present application further provides a photovoltaic system, the photovoltaic system comprising a photovoltaic panel and a charging control circuit according to any one of the first aspects, wherein the charging control circuit is arranged on the photovoltaic panel.

[0025] In a fourth aspect, the present application further provides an energy storage system, the energy storage system comprising an energy storage power supply and a charging control circuit according to any one of the first aspects, wherein the charging control circuit is arranged on the energy storage power supply.

[0026] The above-mentioned charging control circuit, light storage system, photovoltaic system and energy storage system, the charging control circuit includes: a current detection module and a switch module, the first end of the current detection module and the first end of the switch module are connected to the photovoltaic panel, the second end of the switch module is connected to the load circuit, the second end of the current detection module is grounded, and the current detection module includes a thermistor; the switch module is used to conduct the path between the photovoltaic panel and the load circuit when the output voltage or output current of the photovoltaic panel meets the starting condition, and control the photovoltaic panel to charge the load circuit. By setting a thermistor in the charging control circuit, the thermistor has a sensitive characteristic to temperature, that is, the resistance of the thermistor increases sharply when the Curie temperature is reached. Then, when the output of the photovoltaic panel continues to increase, the resistance of the thermistor increases sharply, the load of the load circuit is small, the output voltage of the photovoltaic panel will be quickly pulled up, and the continuous output voltage or output current reaches the starting condition. It can be seen that the charging start time can be accurately judged by the characteristics of the thermistor. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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.

[0028] FIG1 is a first circuit diagram of a charging control circuit in one embodiment;

[0029] FIG2 is a second circuit diagram of a charging control circuit in one embodiment;

[0030] FIG3 is a third circuit diagram of a charging control circuit in one embodiment;

[0031] FIG4 is a fourth circuit diagram of a charging control circuit in one embodiment;

[0032] FIG. 5 is a fifth circuit diagram of a charging control circuit in one embodiment.

[0033] Description of reference numerals:

[0034] 10: Charging control circuit;

[0035] 11: Current detection module;

[0036] 111: power consumption suppression unit;

[0037] 1111: voltage stabilizing subunit;

[0038] 12: switch module;

[0039] 13: Voltage control module;

[0040] 14: Backfeed protection module;

[0041] 20: Photovoltaic panels;

[0042] 30: Load circuit. DETAILED DESCRIPTION

[0043] 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.

[0044] 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.

[0045] Typically, a charging control circuit used to control a photovoltaic panel to supply power to a load circuit is shut down at night to avoid power consumption and restarted after sunrise.

[0046] However, due to the power consumption of the charging control circuit itself, the startup time is critical. If the startup is too early, the output power of the photovoltaic panel cannot meet the power consumption of the power generation system itself, and the charging control circuit will consume the power of the load circuit due to insufficient power supply from the photovoltaic panel. For example, if the load circuit is a battery, when the battery is in a discharged state, the charging control circuit will continue to consume the battery power, causing the battery to be scrapped. If the startup is too late, part of the output energy of the photovoltaic panel will be wasted.

[0047] In the related art, the voltage of the load circuit is mainly detected, and the charging control circuit is judged when to start according to the detected voltage. However, since the photovoltaic panel has different no-load output voltages under different temperatures and different lighting conditions, the detected voltage of the load circuit is inaccurate, and thus the start time is inaccurate. For example, after sunrise on a cloudy morning, the photovoltaic panel output voltage is high, but it cannot provide current at this time.

[0048] In response to the above technical problems, the present application provides a charging control circuit, a photo-storage system, a photovoltaic system and an energy storage system. By setting a thermistor in the charging control circuit, the thermistor has a sensitive characteristic to temperature, that is, the resistance of the thermistor increases sharply when the Curie temperature is reached. Then, when the output of the photovoltaic panel continues to increase, the resistance of the thermistor increases sharply, the load of the load circuit is small, the output voltage of the photovoltaic panel will be quickly pulled up, and the continuous output voltage or output current reaches the starting condition. It can be seen that the charging start time can be accurately judged by the characteristics of the thermistor. 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. Please refer to the following embodiment description for details. The technical solution of the present application is described in detail below.

[0049] In one embodiment, as shown in FIG. 1 , a charging control circuit 10 is provided, the charging control circuit 10 comprising: a current detection module 11 and a switch module 12, wherein a first end of the current detection module 11 and a first end of the switch module 12 are both connected to the photovoltaic panel 20, a second end of the switch module 12 is connected to the load circuit 30, a second end of the current detection module 11 is grounded, and the current detection module 11 comprises a thermistor RT;

[0050] The switch module 12 is used to connect the path between the photovoltaic panel 20 and the load circuit 30 and control the photovoltaic panel 20 to charge the load circuit 30 when the output voltage or output current of the photovoltaic panel 20 meets the start-up condition.

[0051] In order to facilitate the control of the charging process of the photovoltaic panel 20 to the load circuit 30, the charging control circuit 10 can be a separate circuit, which is arranged between the photovoltaic panel 20 and the load circuit 30. The charging control circuit 10 can also be arranged on the photovoltaic panel 20, or the charging control circuit 10 can also be arranged on the load circuit 30. For example, the load circuit 30 can be an energy storage power supply, a battery, or an external power grid.

[0052] In an embodiment of the present application, the switch module 12 is arranged between the photovoltaic panel 20 and the load circuit 30. The current detection module 11 is used to detect the output current of the photovoltaic panel 20. When the switch module 12 is turned on, the photovoltaic panel 20 can charge the load circuit 30; when the switch module 12 is turned off, the photovoltaic panel 20 cannot charge the load circuit 30. Among them, the switch module 12 can be implemented by a switch tube, for example, a triode, a metal oxide semiconductor field effect transistor (Metal Oxide Semiconductor Field Effect Transistor, MOS tube), etc. Alternatively, it can also be implemented by various types of switches, etc. Alternatively, it can also be implemented by some switch chips.

[0053] The current detection module 11 may include a thermistor RT, or may include thermistor RT and other electronic components. For example, the current detection module 11 is a thermistor RT, the first end of the thermistor RT is connected to the photovoltaic panel 20 and the switch module 12, respectively, and the second end of the thermistor RT is grounded.

[0054] Among them, thermistors RT have various specifications. The common characteristic is that they can have a low resistance at room temperature, and the resistance increases sharply at high temperature. This temperature point is called the Curie temperature, which is generally 110℃~130℃. At room temperature, when a current is applied to a thermistor RT with a certain resistance, there will be a certain voltage drop across the thermistor RT. Continuous current will cause the temperature of the thermistor RT to continue to rise. When the temperature of the thermistor RT reaches the Curie temperature, the resistance increases, which in turn causes the voltage drop to increase. After that, only a small current is needed to maintain the thermistor RT at a higher temperature, keeping it in a high resistance state until the current disappears. At the same time, the Curie temperature of the thermistor RT is lower than the glass transition temperature of the printed circuit board (PCB) material, and the continuous operation of the thermistor RT will not affect the safety of the PCB.

[0055] It is understandable that when the sun rises in the morning or due to insufficient sunlight on cloudy days, the output current of the photovoltaic panel 20 is small, and the voltage drop across the thermistor RT is low. The input voltage of the load circuit 30 is also low. When the light gradually increases, the current flowing through the thermistor RT gradually increases, and its temperature gradually increases until it reaches the Curie temperature. At this time, the resistance of the thermistor RT suddenly changes, the voltage drop across the thermistor RT increases, and the subsequent current flowing through the thermistor RT is small. At the same time, the input voltage of the load circuit 30 suddenly increases, and the switch module 12 can be controlled to turn on by the control module in the load circuit 30, and the photovoltaic panel 20 can charge the load circuit 30.

[0056] When the sunshine is insufficient, the output current of the photovoltaic panel 20 will decrease, thereby causing the voltage across the thermistor RT to decrease. When the output current of the photovoltaic panel 20 continues to decrease and cannot maintain the heating power of the thermistor RT, the temperature drops, the resistance of the thermistor RT decreases, and the voltage drop across the thermistor RT decreases. The load circuit 30 cannot detect the voltage, the switch module 12 is in the off state, and the load circuit 30 enters the shutdown or sleep state to reduce power consumption.

[0057] The charging control circuit 10 includes: a current detection module 11 and a switch module 12, wherein the first end of the current detection module 11 and the first end of the switch module 12 are both connected to the photovoltaic panel 20, the second end of the switch module 12 is connected to the load circuit 30, the second end of the current detection module 11 is grounded, and the current detection module 11 includes a thermistor RT; the switch module 12 is used to conduct the path between the photovoltaic panel 20 and the load circuit 30 when the output voltage or output current of the photovoltaic panel 20 meets the start-up condition, and control the photovoltaic panel 20 to charge the load circuit 30. By setting the thermistor RT in the charging control circuit 10, the thermistor RT has a sensitive characteristic to temperature, that is, the resistance of the thermistor RT increases sharply when the Curie temperature is reached. Then, when the output of the photovoltaic panel 20 continues to increase, the resistance of the thermistor RT increases sharply, the load of the load circuit 30 is small, the output voltage of the photovoltaic panel 20 will be quickly pulled up, and the continuous output voltage or output current reaches the start-up condition. It can be seen that the charging start time can be accurately judged by the characteristics of the thermistor RT.

[0058] Assuming that the current detection module 11 includes only one thermistor RT, and the temperature of the thermistor RT reaches the Curie temperature, when the photovoltaic panel 20 is charging the load circuit 30, the temperature of the thermistor RT is relatively high, and the output current of the photovoltaic panel 20 will still be consumed, resulting in partial power loss. In order to avoid this part of power loss, the thermistor RT is ensured to return to normal temperature during the process of the photovoltaic panel 20 charging the load circuit 30, and a power consumption suppression unit 111 is provided in the current detection module 11. In one embodiment, as shown in FIG2 , the current detection module 11 further includes the power consumption suppression unit 111, the first end of the power consumption suppression unit 111 is connected to the thermistor RT, and the second end of the power consumption suppression unit 111 is grounded;

[0059] The power consumption suppression unit 111 is used to close the connection between the thermistor RT and the ground when the output voltage or the output current of the photovoltaic panel 20 meets the start-up condition, so as to suppress the power loss of the thermistor RT.

[0060] In the embodiment of the present application, the power consumption suppression unit 111 is arranged between the thermistor RT and the ground, and the power consumption suppression unit 111 can be regarded as a switch. When the resistance value of the thermistor RT does not reach the Curie temperature, it means that the output voltage of the photovoltaic panel 20 is small and cannot charge the load circuit 30. At this time, the thermistor RT can be grounded through the power consumption suppression unit 111.

[0061] When the thermistor RT reaches the Curie temperature, the resistance of the thermistor RT increases rapidly, and the output of the photovoltaic panel 20 continues to increase. When the output voltage or output current of the photovoltaic panel 20 meets the startup condition, it means that the output voltage or output current of the photovoltaic panel 20 can meet the charging demand of the load circuit 30 and can charge the load circuit 30. At this time, the power consumption suppression unit 111 will close the connection between the thermistor RT and the ground, and the photovoltaic panel 20, the thermistor RT and the power consumption suppression unit 111 cannot form a loop. In this way, the thermistor RT will not consume the output power of the photovoltaic panel 20, and the output power of the photovoltaic panel 20 will be all provided to the load circuit 30 for charging.

[0062] The current detection module 11 also includes a power consumption suppression unit 111, a first end of the power consumption suppression unit 111 is connected to the thermistor RT, and a second end of the power consumption suppression unit 111 is grounded; the power consumption suppression unit 111 is used to close the connection between the thermistor RT and the ground when the output voltage or output current of the photovoltaic panel 20 meets the startup condition, so as to suppress the power loss of the thermistor RT. The power consumption suppression unit 111 is introduced between the thermistor RT and the ground of the current detection module 11. When the output voltage or output current of the photovoltaic panel 20 meets the startup condition, the power consumption suppression unit 111 can cut off the connection between the thermistor RT and the ground, and the photovoltaic panel 20, the thermistor RT and the power consumption suppression unit 111 cannot form a loop. In this way, the thermistor RT will not consume the output power of the photovoltaic panel 20, thereby solving the problem of power loss.

[0063] Next, the specific contents of the power consumption suppression unit 111 are introduced through an embodiment. Referring to FIG. 2 , the power consumption suppression unit 111 includes a first switch tube Q1 and a voltage stabilizing subunit 1111 .

[0064] The first end of the voltage stabilizing subunit 1111 is respectively connected to the first end of the thermistor RT, the photovoltaic panel 20, and the switch module 12, the drain of the first switch tube Q1 is connected to the second end of the thermistor RT, the gate of the first switch tube Q1 is connected to the second end of the voltage stabilizing subunit 1111, and the source of the first switch tube Q1 is grounded.

[0065] Wherein, the first switch tube Q1 can be a MOS tube, which is arranged between the thermistor RT and the ground, that is, the drain of the MOS tube is connected to the thermistor RT, and the source of the MOS tube is grounded. Whether the thermistor RT consumes the output power of the photovoltaic panel 20 is controlled by turning on and off the first switch tube Q1. Specifically, when the first switch tube Q1 is turned on, the photovoltaic panel 20, the thermistor RT and the power consumption suppression unit 111 form a loop, and the thermistor RT will consume the output power of the photovoltaic panel 20. When the first switch tube Q1 is turned off, the photovoltaic panel 20, the thermistor RT and the power consumption suppression unit 111 cannot form a loop, and the thermistor RT will not consume the output power of the photovoltaic panel 20.

[0066] In one embodiment, the voltage stabilizing subunit 1111 includes a resistor R1, a resistor R2 and a first diode DZ1; the first end of the resistor R1 is respectively connected to the first end of the thermistor RT, the photovoltaic panel 20, and the switch module 12, the second end of the resistor R1, the first end of the resistor R2, and the cathode of the first diode DZ1 are all connected to the gate of the first switch tube Q1, and the second end of the resistor R2 and the anode of the first diode DZ1 are both grounded.

[0067] When the photovoltaic panel 20 does not generate electricity at all, the first switch tube Q1 is in the off state. When the photovoltaic panel 20 starts to generate electricity, since the first switch tube Q1 is in the off state, the resistance values ​​of resistors R1 and R2 are large, and the output voltage of the photovoltaic panel 20 increases rapidly. When the common terminal voltage of resistors R1 and R2 is greater than the conduction voltage of the first switch tube Q1, the first switch tube Q1 starts to conduct and enters the linear working area. At this time, the output current of the photovoltaic panel 20 flows through the thermistor RT and resistor R1. The resistance value of the thermistor RT is much smaller than the resistance value of resistor R1, which can be understood as the thermistor RT consumes the output current of the photovoltaic panel 20, and the temperature of the thermistor RT begins to rise. As the output current of the photovoltaic panel 20 gradually increases, the thermistor RT reaches the Curie temperature, and the resistance value suddenly increases, causing the output voltage of the photovoltaic panel 20 to increase. When the output voltage or output current of the photovoltaic panel 20 meets the starting conditions, the first switch tube Q1 can be controlled to be in the off state through the control module or specific control circuit in the load circuit 30. Both the control module and the control circuit are connected to the common end of resistor 1 R1 and resistor 2 R2.

[0068] When the output voltage of the photovoltaic panel 20 drops, the first switch tube Q1 is controlled to be turned on. At this time, the thermistor RT has recovered to a normal resistance value, and the voltage drop across the thermistor RT caused by the output current of the photovoltaic panel 20 is not enough to maintain the first switch tube Q1 in the saturated conduction region, and the first switch tube Q1 is in the linear amplification region. When the output current of the photovoltaic panel 20 further drops, the voltage across the resistor R2 is lower than the conduction voltage of the first switch tube Q1, and the first switch tube Q1 is in the off state.

[0069] In the first case, the current detection module 11 only includes the thermistor RT; in the second case, the current detection module 11 includes the thermistor RT and the power consumption suppression unit 111. It should be emphasized that the resistance of the thermistor RT in the second case should be greater than the resistance of the thermistor RT in the first case, and the current flowing through the thermistor RT can generate a sufficient voltage drop, so that the voltage across the resistor R2 is greater than the turn-on voltage of the first switch tube Q1, and the first switch tube Q1 enters the saturation conduction region. If the resistance of the thermistor RT in the two cases is the same, or the resistance of the thermistor RT in the second case is less than the resistance of the thermistor RT in the first case, the current flowing through the thermistor RT cannot generate a sufficient voltage drop. At this time, the first switch tube Q1 is in the linear working area for a long time, with large power consumption and high heat generation.

[0070] The power consumption suppression unit 111 includes a first switch tube Q1 and a voltage stabilizing subunit 1111; the voltage stabilizing subunit 1111 is respectively connected to the first end of the thermistor RT, the photovoltaic panel 20, and the switch module 12, the drain of the first switch tube Q1 is connected to the second end of the thermistor RT, the gate of the first switch tube Q1 is connected to the second end of the voltage stabilizing subunit 1111, and the source of the first switch tube Q1 is grounded. The voltage stabilizing subunit 1111 includes a resistor R1, a resistor R2, and a first diode DZ1; the first end of the resistor R1 is respectively connected to the first end of the thermistor RT, the photovoltaic panel 20, and the switch module 12, the second end of the resistor R1, the first end of the resistor R2, and the cathode of the first diode DZ1 are all connected to the gate of the first switch tube Q1, and the second end of the resistor R2 and the anode of the first diode DZ1 are all grounded. The power consumption suppression unit 111 composed of the switch tube can timely conduct or cut off the connection between the thermistor RT and the ground according to the change of the resistance value of the thermistor RT, so as to ensure that the thermistor RT will not consume the output power of the photovoltaic panel 20 during the process of charging the load circuit 30 by the photovoltaic panel 20. At the same time, the voltage stabilizing subunit 1111 composed of two resistors and a diode can stabilize the output voltage of the photovoltaic panel 20 to ensure the stability of the output voltage of the photovoltaic panel 20.

[0071] Whether the power consumption suppression unit 111 closes the connection between the thermistor RT and the ground can be controlled by the control module in the load circuit 30, or by the voltage control module 13. Then, in one embodiment, the specific content of the voltage control module 13 is introduced. As shown in FIG3 , the charging control circuit 10 also includes a voltage control module 13. The first end of the voltage control module 13 is respectively connected to the photovoltaic panel 20, the thermistor RT, and the switch module 12, and the second end of the voltage control module 13 is connected to the power consumption suppression unit 111; the voltage control module 13 is used to send a voltage control signal to the power consumption suppression unit 111 when the output voltage or output current of the photovoltaic panel 20 meets the start-up condition.

[0072] In the embodiment of the present application, the voltage control module 13 can be understood as a control circuit that controls the first switch tube Q1 to be turned on or off, and the voltage control module 13 has the same function as the control module in the load circuit 30. Specifically, when the output voltage or output current of the photovoltaic panel 20 does not meet the start-up condition, the voltage control module 13 can control the first switch tube Q1 to be turned on; when the output voltage or output current of the photovoltaic panel 20 meets the start-up condition, the voltage control module 13 can control the first switch tube Q1 to be turned off.

[0073] In one embodiment, the voltage control module 13 includes: a second switch tube Q2, a resistor R3, a resistor R4, a second diode DZ2 and a third diode DZ3; the cathode of the second diode DZ2 is connected to the photovoltaic panel 20, the thermistor RT and the switch module 12, the anode of the second diode DZ2 is connected to the first end of the resistor R3, the second end of the resistor R3 is respectively connected to the first end of the resistor R4, the cathode of the third diode DZ3 and the gate of the second switch tube Q2, the drain of the second switch tube Q2 is connected to the power consumption suppression unit 111, the second end of the resistor R4, the anode of the third diode DZ3 and the source of the second switch tube Q2 are all grounded.

[0074] The second switch tube Q2 may be a MOS tube, which is arranged between the common end of the resistor R1 and the resistor R2 and the ground, that is, the drain of the MOS tube is connected to the common end of the resistor R1 and the resistor R2, and the source of the MOS tube is grounded.

[0075] When the photovoltaic panel 20 does not generate electricity at all, the first switch tube Q1 and the second switch tube Q2 are both in the off state.

[0076] When the photovoltaic panel 20 starts to generate electricity and the output voltage or output current of the photovoltaic panel 20 meets the starting condition, the second diode DZ2 is turned on, so that the second switch tube Q2 is turned on. At this time, the common terminal voltage of the resistor R1 and the resistor R2 is pulled low, that is, the gate of the first switch tube Q1 is grounded, and the first switch tube Q1 is in the off state.

[0077] The charging control circuit 10 further includes a voltage control module 13, the first end of which is respectively connected to the photovoltaic panel 20, the thermistor RT, and the switch module 12, and the second end of which is connected to the power consumption suppression unit 111; the voltage control module 13 is used to send a voltage control signal to the power consumption suppression unit 111 when the output voltage or output current of the photovoltaic panel 20 meets the start-up condition. The voltage control module 13 includes: a second switch tube Q2, a resistor three R3, a resistor four R4, a second diode DZ2, and a third diode DZ3; the cathode of the second diode DZ2 is connected to the photovoltaic panel 20, the thermistor RT, and the switch module 12, the anode of the second diode DZ2 is connected to the first end of the resistor three R3, the second end of the resistor three R3 is respectively connected to the first end of the resistor four R4, the cathode of the third diode DZ3, and the gate of the second switch tube Q2, the drain of the second switch tube Q2 is connected to the power consumption suppression unit 111, and the second end of the resistor four R4, the anode of the third diode DZ3, and the source of the second switch tube Q2 are all grounded. The power consumption suppression unit 111 is controlled by a voltage control module 13 composed of a switch tube, two resistors and two diodes to control the connection between the thermistor RT and the ground, so that power consumption can be accurately suppressed during the process of the photovoltaic panel 20 charging the load circuit 30.

[0078] Although the above-mentioned method of setting the power consumption suppression unit 111 in the current detection module 11 can suppress the power consumption of the thermistor RT during the charging process, when the first switch tube Q1 is in the linear working area, the heat is serious and the required power consumption is large. In order to suppress the power consumption of the first switch tube Q1 in the linear working area, the first switch tube Q1 in the above-mentioned embodiment can be replaced by a relay KJ. Then, in one embodiment, as shown in FIG4, the current detection module 11 also includes a relay KJ, a first end of the relay KJ is connected to the thermistor RT, a second end of the relay KJ is connected to the control module in the load circuit 30, and a third end of the relay KJ is grounded;

[0079] The control module is used to control the relay KJ to close when the output voltage or output current of the photovoltaic panel 20 does not meet the starting condition; and to control the relay KJ to open when the output voltage or output current of the photovoltaic panel 20 meets the starting condition.

[0080] Relay KJ does not consume power during operation. When the output voltage or output current of the photovoltaic panel 20 meets the starting conditions, the load circuit 30 can work normally. At this time, the relay KJ is controlled to be disconnected. When the relay KJ is disconnected, it only bears voltage but not current, and the power consumption at the moment of disconnection is not large. After the relay KJ is disconnected, the thermistor RT no longer consumes the output power of the photovoltaic panel 20, its temperature gradually decreases, and its resistance returns to the normal resistance. When the output power of the photovoltaic panel 20 decreases, the control module of the load circuit 30 stops driving the relay KJ, the contacts of the relay KJ are closed, and the output power of the photovoltaic panel 20 is small, so that the power consumption at the moment of the relay KJ closing is not large.

[0081] The current detection module 11 also includes a relay KJ, a first end of the relay KJ is connected to the thermistor RT, a second end of the relay KJ is connected to the control module in the load circuit 30, and a third end of the relay KJ is grounded; the control module is used to control the relay KJ to close when the output voltage or output current of the photovoltaic panel 20 does not meet the start-up conditions; and to control the relay KJ to open when the output voltage or output current of the photovoltaic panel 20 meets the start-up conditions. By setting the relay KJ between the thermistor RT and the ground, and by controlling the closing and opening of the relay KJ, the thermistor RT is not subjected to the output power of the photovoltaic panel 20 during the charging process. At the same time, it can prevent the charging control circuit 10 from frequently switching when the output power of the photovoltaic panel 20 is insufficient.

[0082] In order to avoid the charging control circuit 10 consuming the power of the load circuit 30 when the output power of the photovoltaic panel 20 is insufficient or unstable, a backfeed protection module 14 can also be set between the thermistor RT and the switch module 12, and the backfeed protection module 14 can prevent the current in the load circuit 30 from flowing to the photovoltaic panel 20. In one embodiment, as shown in FIG5, the charging control circuit 10 further includes a backfeed protection module 14, the first end of the backfeed protection module 14 is respectively connected to the photovoltaic panel 20 and the thermistor RT, and the second end of the backfeed protection module 14 is connected to the switch module 12; the backfeed protection module 14 is used to block the current in the load circuit 30 from flowing to the photovoltaic panel 20.

[0083] The backfeed protection module 14 includes a fourth diode DZ4 or a third switch tube.

[0084] When the backfeed protection module 14 is a fourth diode DZ4, referring to FIG5 , the anode of the fourth diode DZ4 is connected to the photovoltaic panel 20 and the thermistor RT respectively, and the cathode of the fourth diode DZ4 is connected to the input end of the switch module 12. The characteristics of the diode ensure that the current in the load circuit 30 does not flow to the photovoltaic panel 20.

[0085] When the backfeed protection module 14 is a third switch tube, the third switch tube may be a MOS tube, and a gate of the MOS tube is connected to the control module in the load circuit 30 .

[0086] The charging control circuit 10 further includes a backfeed protection module 14, a first end of which is connected to the photovoltaic panel 20 and the thermistor RT respectively, and a second end of which is connected to the switch module 12; the backfeed protection module 14 is used to block the current in the load circuit 30 from flowing to the photovoltaic panel 20. By arranging the backfeed protection module 14 between the thermistor RT and the switch module 12, the current in the load circuit 30 can be blocked from flowing to the photovoltaic panel 20, so as to prevent the thermistor RT from consuming the power of the load circuit 30.

[0087] In summary, the charging control circuit 10 provided in the present application includes three different situations. In the first situation, the current detection module 11 includes a thermistor RT, and the thermistor RT has a sensitive characteristic to temperature, that is, the resistance of the thermistor RT increases sharply when the Curie temperature is reached. Then, when the output of the photovoltaic panel 20 continues to increase, the resistance of the thermistor RT increases sharply, the load of the load circuit 30 is small, the output voltage of the photovoltaic panel 20 will be quickly pulled up, and the continuous output voltage or output current reaches the starting condition. It can be seen that the charging start time can be accurately judged by the characteristics of the thermistor RT. In this case, the thermistor RT will always consume part of the output power of the photovoltaic panel 20.

[0088] In the second case, the current detection module 11 includes a thermistor RT and a power consumption suppression unit 111 . The power consumption suppression unit 111 can suppress the power loss of the thermistor RT when the photovoltaic panel 20 is charging the load circuit 30 .

[0089] In the third case, the current detection module 11 includes a thermistor RT and a relay KJ. By turning on and off the relay KJ, the power loss of the thermistor RT can be suppressed during the part of time when the photovoltaic panel 20 is not charging the load circuit 30 and during the process when the photovoltaic panel 20 is charging the load circuit 30.

[0090] In one embodiment, a photovoltaic storage system is also provided, which includes a photovoltaic panel 20, a load circuit 30 and a charging control circuit 10. In this case, the charging control circuit 10 is an independent circuit, and the charging control circuit 10 is independently arranged between the photovoltaic panel 20 and the load circuit 30.

[0091] In another embodiment, a photovoltaic system is provided, which includes a photovoltaic panel 20 and a charging control circuit 10, wherein the charging control circuit 10 is disposed on the photovoltaic panel 20. It can be understood that the charging control circuit 10 and the photovoltaic panel 20 are disposed in an integrated manner.

[0092] In another embodiment, an energy storage system is provided, which includes an energy storage power supply and a charging control circuit 10, wherein the charging control circuit 10 is arranged on the energy storage power supply. It can be understood that the charging control circuit 10 and the load circuit 30 are arranged in an integrated manner.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] 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 charging control circuit, characterized in that: The charging control circuit comprises: a current detection module and a switch module, wherein a first end of the current detection module and a first end of the switch module are both connected to the photovoltaic panel, a second end of the switch module is connected to the load circuit, a second end of the current detection module is grounded, and the current detection module comprises a thermistor; The switch module is used to connect the path between the photovoltaic panel and the load circuit and control the photovoltaic panel to charge the load circuit when the output voltage or output current of the photovoltaic panel meets the start-up condition.

2. The circuit according to claim 1, characterized in that The current detection module further includes a power consumption suppression unit, a first end of the power consumption suppression unit is connected to the thermistor, and a second end of the power consumption suppression unit is grounded; The power consumption suppression unit is used to close the connection between the thermistor and the ground when the output voltage or the output current of the photovoltaic panel meets the start-up condition, so as to suppress the power loss of the thermistor.

3. The circuit according to claim 2, characterized in that The power consumption suppression unit includes a first switch tube and a voltage stabilizing subunit; The first end of the voltage stabilizing subunit is respectively connected to the first end of the thermistor, the photovoltaic panel, and the switch module, the drain of the first switch tube is connected to the second end of the thermistor, the gate of the first switch tube is connected to the second end of the voltage stabilizing subunit, and the source of the first switch tube is grounded.

4. The circuit according to claim 3, characterized in that The voltage stabilizing subunit includes a resistor 1, a resistor 2 and a first diode; The first end of the resistor 1 is respectively connected to the first end of the thermistor, the photovoltaic panel, and the switch module; the second end of the resistor 1, the first end of the resistor 2, and the cathode of the first diode are all connected to the gate of the first switch tube; the second end of the resistor 2 and the anode of the first diode are both grounded.

5. The circuit according to any one of claims 2 to 4, characterized in that: The charging control circuit further comprises a voltage control module, a first end of the voltage control module is respectively connected to the photovoltaic panel, the thermistor, and the switch module, and a second end of the voltage control module is connected to the power consumption suppression unit; The voltage control module is used to send a voltage control signal to the power consumption suppression unit when the output voltage or output current of the photovoltaic panel meets the start-up condition.

6. The circuit according to claim 5, characterized in that The voltage control module includes: a second switch tube, a third resistor, a fourth resistor, a second diode and a third diode; The cathode of the second diode is connected to the photovoltaic panel, the thermistor, and the switch module, the anode of the second diode is connected to the first end of the resistor three, the second end of the resistor three is respectively connected to the first end of the resistor four, the cathode of the third diode, and the gate of the second switch tube, the drain of the second switch tube is connected to the power consumption suppression unit, and the second end of the resistor four, the anode of the third diode, and the source of the second switch tube are all grounded.

7. The circuit according to claim 1, characterized in that The current detection module further includes a relay, a first end of the relay is connected to the thermistor, a second end of the relay is connected to the control module in the load circuit, and a third end of the relay is grounded; The control module is used to control the relay to close when the output voltage or output current of the photovoltaic panel does not meet the starting condition; and to control the relay to open when the output voltage or output current of the photovoltaic panel meets the starting condition.

8. The circuit according to claim 1, characterized in that The charging control circuit further comprises a backfeed protection module, wherein a first end of the backfeed protection module is respectively connected to the photovoltaic panel and the thermistor, and a second end of the backfeed protection module is connected to the switch module; The backfeed protection module is used to block the current in the load circuit from flowing toward the photovoltaic panel.

9. The circuit according to claim 8, characterized in that The backfeed protection module includes a fourth diode or a third switch tube.

10. A solar energy storage system, characterized in that: The photovoltaic storage system comprises a photovoltaic panel, a load circuit and a charging control circuit as described in any one of claims 1-9.

11. A photovoltaic system, characterized in that: The photovoltaic system comprises a photovoltaic panel and a charging control circuit according to any one of claims 1 to 9, wherein the charging control circuit is arranged on the photovoltaic panel.

12. An energy storage system, characterized in that: The energy storage system comprises an energy storage power supply and a charging control circuit as claimed in any one of claims 1 to 9, wherein the charging control circuit is arranged on the energy storage power supply.

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