Photovoltaic weak current elimination circuit and energy storage power source

Abstract

The present application relates to the technical field of power supply protection, and mainly provides a photovoltaic weak current removal circuit and an energy storage power supply, which includes a discharge trigger module, a lock module, a discharge unlock module, and a discharge module, the discharge trigger module being connected to the discharge module, the discharge unlock module, and the lock module, and the discharge module, the discharge trigger module, and the discharge unlock module are all used to connect to a photovoltaic input source. The discharge trigger module is used to output a first control signal for controlling the discharge module to discharge the energy of the photovoltaic input source when the output voltage of the photovoltaic input source is greater than a preset voltage, and after the operation of the discharge module, the lock module maintains the output of the first control signal by the discharge trigger module. This can improve the stability of the energy storage power supply. After the operation of the discharge module, if the output voltage of the photovoltaic input source is greater than a preset voltage, the discharge unlock module controls the discharge trigger module to output a second control signal to stop the operation of the discharge module. This can improve the utilization rate of the photovoltaic input source.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to a Chinese patent application filed with the China Patent Office on April 20, 2023, bearing application number 202310423766.X and entitled "Photovoltaic Weak Current Removal Circuit and Energy Storage Power Source", the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the technical field of power protection, and in particular to photovoltaic weak current removal circuits and energy storage power supplies. [Background technology]

[0003] Solar panels absorb sunlight and convert solar energy into electrical energy, and after the solar energy in the solar panels is converted into electrical energy, it needs to be stored in an energy storage power supply or power supply device. When the sunlight is blocked by the shade of a tree or dark clouds during the operation of the solar panel, or when working at night, the voltage output of the solar panel becomes unstable, for example, on a bright moonlit night, the solar panel outputs a weak voltage, which can start the energy storage power supply, but the actual output power is not enough to meet the power consumption inside the system, and the system immediately shuts down, and thus the energy storage power supply alternates between being started and being shut down, making the operation of the system unstable and greatly reducing the service life of the energy storage power supply. Summary of the Invention

[0004] The embodiments of the present application mainly solve the technical problem that the solar panel outputs a weak voltage, which leads to unstable operation of the energy storage power supply and large life loss.

[0005] In order to solve the above-mentioned technical problems, a technical solution adopted in the embodiments of the present application is a photovoltaic weak current elimination circuit, which includes a discharge trigger module, a lock module, a discharge unlock module and a discharge module, the discharge trigger module is connected to the discharge module, the lock module and the discharge unlock module respectively, the discharge module, the discharge trigger module and the discharge unlock module are all used to connect to a photovoltaic input source; the discharge trigger module is used for outputting a first control signal to the discharge module when the output voltage of the photovoltaic input source is greater than a preset voltage, and controlling the discharge module to operate and discharge the energy of the photovoltaic input source; The lock module is used to maintain the discharge trigger module outputting the first control signal after the discharge module is operated, so that the discharge module maintains operation; The discharge unlock module is configured to determine whether the output voltage of the photovoltaic input source is greater than a preset voltage after the operation of the discharge module, and if the output voltage of the photovoltaic input source is greater than the preset voltage, to control the discharge trigger module to output a second control signal to provide a photovoltaic weak current elimination circuit used to stop the operation of the discharge module.

[0006] The discharge trigger module includes a voltage division driving unit and a trigger unit; The voltage division driving unit is respectively connected to the photovoltaic input source, the discharge unlocking module, the locking module and the triggering unit, and the triggering unit is respectively connected to the locking module and the discharge module; The voltage dividing drive unit is used for dividing the output voltage and inputting the divided output voltage to the trigger unit; The trigger unit may be configured to determine whether the divided output voltage reaches a trigger threshold to determine whether the output voltage is greater than the preset voltage, and output a first control signal to the discharge module when the divided output voltage reaches the trigger threshold.

[0007] The voltage divider driving unit includes a resistor R2, a resistor R8, and a capacitor C2; The first end of the resistor R2 is connected to the photovoltaic input source, the second end of the resistor R2 is respectively connected to the discharge unlock module, the control end of the trigger unit and the first end of the resistor R8, and the second end of the resistor R8 is used to ground, and the capacitor C2 and the resistor R8 are connected in parallel.

[0008] The trigger unit includes a switch tube Q2, a switch tube Q4, a resistor R4, a resistor R6, and a resistor R9; The control end of the switch tube Q4 is connected to the second end of the resistor R2, the first end of the switch tube Q4 is connected to the control end of the switch tube Q2 through the resistor R6, the second end of the switch tube Q4 is used for grounding, the control end of the switch tube Q2 is further connected to the locking module through the resistor R6, the first end of the switch tube Q2 is connected to the photovoltaic input source through the resistor R4, and the second end of the switch tube Q2 is grounded through the resistor R9.

[0009] The discharge module includes a resistor R5 and a switch tube Q5; The control end of the switch tube Q5 may be connected to the discharge trigger module, a first end of the switch tube Q5 may be connected to the photovoltaic input source through the resistor R5, and a second end of the switch tube Q5 may be used for grounding.

[0010] The locking module may be used to adjust the ratio of the divided output voltage so as to maintain the discharge trigger module outputting the first control signal after the discharge module is operated.

[0011] The locking module includes a switch tube Q1 and a resistor R3; The control end of the switch tube Q1 may be connected to the trigger unit, the first end of the switch tube Q1 may be connected to the first end of the voltage divider driving unit via the resistor R3, and the second end of the switch tube Q1 may be connected to the second end of the voltage divider driving unit.

[0012] The discharge unlock module may determine, after operation of the discharge module, whether the output voltage is greater than the predetermined voltage and whether the period during which the output voltage is greater than the predetermined voltage exceeds a predetermined time, and if the period during which the output voltage is greater than the predetermined voltage exceeds the predetermined time, control the discharge trigger module to output the second control signal.

[0013] The discharge unlock module includes: a diode ZD1, a diode ZD2, a capacitor C1, a switch tube Q3, a resistor R1 and a resistor R7; The cathode of the diode ZD1 is connected to the photovoltaic input source through the resistor R1, the anode of the diode ZD1 is connected to the first end of the capacitor C1 and the cathode of the diode ZD2, the anode of the diode ZD2 is connected to the control end of the switch tube Q3, the first end of the switch tube Q3 is connected to the control end of the discharge trigger module, the second end of the switch tube Q3 is grounded, and the second end of the capacitor C1 is grounded, and the resistor R7 and the capacitor C1 are connected in parallel.

[0014] In order to solve the above-mentioned technical problems, another technical solution adopted in the embodiments of this application is: BMS module and Batteries and and a photovoltaic weak current elimination circuit as described above, wherein the BMS module provides an energy storage power source connected to the discharge module and the battery respectively.

[0015] Different from the case of the related art, in the photovoltaic weak current elimination circuit and the energy storage power supply according to the embodiment of the present application, the photovoltaic weak current elimination circuit includes a discharge trigger module, a lock module, a discharge unlock module, and a discharge module, the discharge trigger module is respectively connected to the discharge module, the lock module, and the discharge unlock module, and the discharge module, the discharge trigger module, and the discharge unlock module are all used to connect to a photovoltaic input source. The discharge trigger module is used to output a first control signal to the discharge module and control the discharge module to operate to discharge the energy of the photovoltaic input source when the output voltage of the photovoltaic input source is greater than a preset voltage, and after the operation of the discharge module, the lock module maintains the output of the first control signal by the discharge trigger module, so that the discharge module maintains operation, and after the operation of the discharge module, if the output voltage of the photovoltaic input source is still greater than the preset voltage, the discharge unlock module controls the discharge trigger module to output a second control signal to stop the operation of the discharge module. According to this, when a photovoltaic input source is turned on and the output voltage of the photovoltaic input source, i.e., the photovoltaic voltage, reaches a preset voltage, the discharge trigger module and the lock module are operated to control the photovoltaic input source to perform on-load discharge. Whether the photovoltaic input source has a low voltage is determined by determining whether the photovoltaic voltage after the on-load discharge reaches a preset voltage. If the photovoltaic input source has a low voltage, the operation of the discharge module is maintained to avoid the waste of electrical energy caused by repeatedly starting the energy storage power source when the photovoltaic input source has a low voltage. On the other hand, if the photovoltaic input source is not a low voltage, i.e., the photovoltaic voltage is sufficient to charge the energy storage power source, the operation of the discharge module is controlled to be stopped, allowing the photovoltaic input source to supply power to the energy storage power source and improving the utilization rate of the photovoltaic input source. [Brief description of the drawings]

[0016] One or more embodiments are illustratively described in the accompanying drawings, which correspond thereto, but which are not intended to be limiting of the embodiments, in which like reference numbers represent similar elements, and in which the figures are not to be drawn to scale unless otherwise specified. [Figure 1] 1 is an application scenario of an energy storage power source according to an embodiment of the present application. [Diagram 2] 1 is a block diagram showing the configuration of a photovoltaic weak current removal circuit according to an embodiment of the present application; [Diagram 3] FIG. 11 is a block diagram showing the configuration of a photovoltaic weak current removal circuit according to another embodiment of the present application. [Figure 4] FIG. 2 is a circuit diagram of a photovoltaic weak current removal circuit according to an embodiment of the present application. [Diagram 5] FIG. 11 is a circuit diagram of a photovoltaic weak current removal circuit according to another embodiment of the present application. [Figure 6] FIG. 11 is a circuit diagram of a photovoltaic weak current removal circuit according to still another embodiment of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] In order to make the purpose, technical solution and advantages of the present application more clear, the present application will be described in more detail with reference to the drawings and examples below. It should be understood that the specific examples described herein are only for the purpose of illustrating the present application, and are not intended to limit the present application.

[0018] In addition, unless inconsistent, the features in the embodiments of the present application may be combined with each other, and all are within the scope of protection of the present application. In addition, although the schematic diagram of the device is divided into functional modules and a logical order is shown in the flowchart, in some cases, the steps shown or described may be divided differently from the division of modules in the schematic diagram of the device, or may be performed in a different order from the order in the flowchart.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art of this application. The terms used in the specification of this application are only for describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0020] Referring to FIG. 1, which is an application scenario of an energy storage power source according to an embodiment of the present application, the application scenario includes an energy storage power source 100 and a photovoltaic power input source 200, and the energy storage power source 100 and the photovoltaic power input source 200 are connected to each other, as shown in FIG. 1. Specifically, the photovoltaic power input source 200 is configured to receive sunlight, convert the sunlight into electrical energy, input the electrical energy to the energy storage power source 100, and store the electrical energy in the energy storage power source 100. Here, as shown in FIG. 1, the energy storage power source 100 includes a photovoltaic weak current removal circuit 10, a BMS module 20, and a battery 30, and the photovoltaic weak current removal circuit 10 and the BMS module 20 are both connected to the photovoltaic power input source 200, and the BMS module 20 is also connected to the battery 30. When the photovoltaic power input source 200 receives sunlight, it converts the sunlight into electrical energy and inputs it to the photovoltaic weak current removal circuit 10. When the photovoltaic weak current elimination circuit 10 receives the electric energy, it determines whether to discharge the electric energy based on the electric energy. If the electric energy is not discharged, it is transmitted to the BMS module 20, which wakes up the BMS system and controls the photovoltaic input source 200 to supply power to the battery 30. When the BMS module 20 detects the wake-up signal, it controls the battery 30 to start operating based on the wake-up signal, and stores the electric energy in the battery 30. When the electric energy is discharged, the photovoltaic weak current elimination circuit 10 discharges the photovoltaic input source 200, thereby avoiding the BMS module 20 from being repeatedly started when the photovoltaic input source 200 is at a weak voltage, and improving the stability of the energy storage power source 100. It is noted that the BMS module 20 includes an activation or wake-up unit for waking up the BMS module 20 when the photovoltaic voltage of the photovoltaic input source 200 reaches a preset voltage.Therefore, in this embodiment, even if the photovoltaic voltage is smaller than the preset voltage immediately after the photovoltaic input source 200 is turned on and the photovoltaic weak current removal circuit 10 is not operating, the electrical energy transmitted from the photovoltaic input source 200 to the BMS module 20 cannot satisfy the conditions for waking up the BMS module 20.

[0021] 2, which is a configuration block diagram of a photovoltaic weak current elimination circuit according to an embodiment of the present application, the photovoltaic weak current elimination circuit 10 includes a discharge trigger module 11, a lock module 12, a discharge unlock module 13, and a discharge module 14, as shown in Fig. 2. The discharge trigger module 11 is respectively connected to the discharge module 14, the lock module 12, and the discharge unlock module 13, and the discharge module 14, the discharge trigger module 11, and the discharge unlock module 13 are all used to connect to the photovoltaic input source 200.

[0022] The photovoltaic input source 200 outputs a corresponding output voltage in real time according to the current solar light, and the discharge trigger module 11 receives the output voltage and judges whether the output voltage exceeds a preset voltage, and if the output voltage is greater than the preset voltage, outputs a first control signal to the discharge module 14, controls the discharge module 14 to start operating, and causes the discharge module 14 to discharge the energy of the photovoltaic input source 200. Here, the preset voltage may be the start-up voltage of the BMS module 20, or may be a voltage value designed based on the start-up voltage and safety redundancy.

[0023] Here, as shown in FIG. 2, the discharge trigger module 11 includes a voltage division driving unit 111 and a trigger unit 112, the voltage division driving unit 111 is respectively connected to the photovoltaic input source 200, the discharge unlock module 13, the lock module 12 and the trigger unit 112, and the trigger unit 112 is respectively connected to the lock module 12 and the discharge module 14.

[0024] When the photovoltaic input source 200 outputs the output voltage, the voltage division driving unit 111 divides the output voltage and inputs the divided output voltage to the trigger unit 112. When the trigger unit 112 receives the divided output voltage, it judges whether the divided output voltage reaches a trigger threshold to judge whether the output voltage is greater than the preset voltage. When the divided output voltage reaches the trigger threshold, the trigger unit 112 outputs a first control signal to the discharge module 14 to control the discharge module 14 to start operating. Here, the trigger threshold is the operating voltage of the trigger unit 112. When the divided output voltage is greater than the operating voltage of the trigger unit 112, the trigger unit 112 starts operating and outputs a first control signal to the discharge module 14.

[0025] Specifically, referring to FIG. 4, which is a circuit diagram of a photovoltaic weak current elimination circuit according to an embodiment of the present application, the voltage dividing driving unit 111 includes a resistor R2, a resistor R8 and a capacitor C2, and the trigger unit 112 includes a switch tube Q2, a switch tube Q4, a resistor R4, a resistor R6 and a resistor R9, as shown in FIG.

[0026] Here, the first end of the resistor R2 is connected to the photovoltaic input source 200, the second end of the resistor R2 is respectively connected to the discharge unlock module 13, the control end of the trigger unit 112, and the first end of the resistor R8, and the second end of the resistor R8 is grounded, and the capacitor C2 and the resistor R8 are connected in parallel. When the photovoltaic input source 200 outputs the output voltage, the resistor R2 and the resistor R8 divide the output voltage, and input the divided output voltage to the trigger unit 112, and the trigger unit 112 determines whether to output the first control signal according to the divided output voltage.

[0027] The control end of the switch tube Q4 is connected to the second end of the resistor R2, the first end of the switch tube Q4 is connected to the control end of the switch tube Q2 through the resistor R6, the second end of the switch tube Q4 is used for grounding, the control end of the switch tube Q2 is further connected to the locking module 12 through the resistor R6, the first end of the switch tube Q2 is connected to the photovoltaic input source 200 through the resistor R4, and the second end of the switch tube Q2 is grounded through the resistor R9. When the switch tube Q4 receives the divided output voltage, it judges whether the divided output voltage is greater than the trigger threshold, and if the divided output voltage is greater than the trigger threshold, the switch tube Q4 turns on with the divided output voltage, and at this time, the switch tube Q2 also turns on with its control end connected to ground via resistor R6, and when the switch tube Q2 turns on, it outputs a first control signal to the discharge module 14, so that the discharge module 14 discharges the electric energy of the photovoltaic input source 200. In addition, in order to ensure the withstand voltage value and power consumption of the resistor R4, it is necessary to refer to the maximum voltage of the photovoltaic input source 200 when selecting the type of the resistor R4.

[0028] In some embodiments, the switch tube Q2 may be directly connected to the locking module 12, as shown in Figure 5, which is a circuit diagram of a photovoltaic weak current elimination circuit according to another embodiment of the present application. The control end of the switch tube Q4 is connected to the resistor R2, and the first end of the switch tube Q4 is respectively connected to the locking module 12 and the control end of the switch tube Q2 through the resistor R6, and the control end of the switch tube Q2 is also connected to the locking module 12.

[0029] The locking module 12 is used to maintain the discharge trigger module 11 outputting the first control signal after the operation of the discharge module 14, so that the discharge module 14 maintains operation. In one embodiment, after the discharge module 14 starts to operate based on the first control signal, the locking module 12 maintains the discharge trigger module 11 outputting the first control signal to the discharge module 14 by adjusting the ratio of the divided output voltage so that the divided output voltage remains greater than the trigger threshold. Specifically, the discharge module is driven and operates based on the first control signal output by the discharge trigger module, so that the above-mentioned "after operation of the discharge module" can also be understood as "after the discharge trigger module outputs the first control signal." Note that the output voltage of the photovoltaic input source 200 is affected by light irradiation, and when light irradiation is insufficient, i.e., when the photovoltaic input source 200 has a weak voltage, its no-load voltage can reach the start-up voltage of the BMS module 20, for example, 12V. However, when a load is connected to the photovoltaic power input source 200, the output voltage of the photovoltaic power input source 200 becomes low. Therefore, after the discharge module 14 operates, that is, after a load is applied to the photovoltaic power input source 200, it is necessary to maintain the discharge trigger module 11 outputting the first control signal by the lock module 12 in order to keep the discharge module 14 on. Then, after the discharge module 14 is turned on, it is determined again whether the output voltage of the photovoltaic power input source 200 is greater than a preset voltage, and further whether the output of the photovoltaic power input source 200 is a weak voltage.

[0030] Here, as shown in FIG. 4, the locking module 12 includes a switch tube Q1 and a resistor R3, the control end of the switch tube Q1 is connected to the trigger unit 112, the first end of the switch tube Q1 is connected to the first end of the voltage divider driving unit 111 via the resistor R3, and the second end of the switch tube Q1 is connected to the second end of the voltage divider driving unit 111. When the switch tube Q4 is turned on, the switch tube Q1 and the switch tube Q2 are also turned on accordingly. As a result of the switch tube Q1 being turned on, the resistor R2 and the resistor R3 are connected in parallel, and the resistor R8 and the resistor R8 are used to divide the voltage to increase the input voltage of the switch tube Q4. This ensures that the input voltage of the switch tube Q4 remains greater than the trigger threshold after the switch tube Q2 outputs the first control signal for controlling the discharge module 14 to operate, so that the switch tube Q4 is kept on, and the discharge module 14 is kept discharging the electric energy of the photovoltaic input source 200. Here, the resistance value of the resistor R3 is smaller than the resistance value of the resistor R2. Note that the photovoltaic input source 200 is connected to the discharge module 14, so that when the discharge module 14 is turned on, the output voltage of the photovoltaic input source 200 is lower. At this time, by providing the switch tube Q1 and resistor R3, when the discharge module 14 is turned on, the resistor R2 and the resistor R3 are connected in parallel to reduce the divided voltage in the resistor R2, and the voltage in the resistor R8 can correspond to the continuous on of the switch tube Q4. This can prevent the discharge trigger module 11 from repeatedly switching the operating state at low voltage, and can improve the reliability of the photovoltaic weak current elimination circuit 10.

[0031] In another embodiment, as shown in Fig. 5, the control end of the switch tube Q1 is connected to the first end of the resistor R6, the first end of the switch tube Q1 is connected to the photovoltaic input source 200 through the resistor R3, and the second end of the switch tube Q1 is connected to the second end of the resistor R2. When the switch tube Q4 is turned on, the switch tube Q1 is connected to ground through the resistor R6 and turned on, and at this time, the resistor R3 and the resistor R2 are connected in parallel to reduce the divided voltage in the resistor R2, thereby maintaining the switch tube Q4 on, and thus maintaining the discharge module 14 to discharge the electrical energy of the photovoltaic input source 200.

[0032] In another embodiment, the locking module 12 may also be connected to the discharge module 14, as shown in FIG. 3, which is a block diagram of a photovoltaic weak current removal circuit according to another embodiment of the present application, the locking module 12 is respectively connected to the discharge module 14 and the discharge trigger module 11, the discharge trigger module 11 is respectively connected to the discharge module 14 and the discharge unlock module 13, and the discharge module 14, the discharge trigger module 11 and the discharge unlock module 13 are all used to connect to the photovoltaic input source 200. Here, the discharge trigger module 11 includes a voltage divider driving unit 111 and a trigger unit 112, the voltage divider driving unit 111 is respectively connected to the photovoltaic input source 200, the discharge unlock module 13, the locking module 12 and the trigger unit 112, and the trigger unit 112 is connected to the discharge module 14.

[0033] Specifically, as shown in Fig. 6, which is a circuit diagram of a photovoltaic weak current elimination circuit according to another embodiment of the present application, the voltage dividing drive unit 111 includes a resistor R2, a resistor R8 and a capacitor C2, and the trigger unit 112 includes a switch tube Q2, a switch tube Q4, a resistor R4, a resistor R6 and a resistor R9. The connection relationship of the voltage dividing drive unit 111 is the same as that of Fig. 4.

[0034] The control end of the switch tube Q4 is connected to the second end of the resistor R2, the first end of the switch tube Q4 is connected to the control end of the switch tube Q2 through the resistor R6, the second end of the switch tube Q4 is used for grounding, the first end of the switch tube Q2 is connected to the photovoltaic input source 200 through the resistor R4, and the second end of the switch tube Q2 is grounded through the resistor R9. When the switch tube Q4 is turned on by the divided output voltage, the switch tube Q2 is also turned on accordingly, and as a result of the switch tube Q2 being turned on, the output voltage of the photovoltaic input source 200 is input to the discharge module 14 through the switch tube Q2, and the discharge module 14 is controlled to be turned on.

[0035] As shown in Figures 4 to 6, the discharge module 14 includes a resistor R5 and a switch tube Q5, the control end of the switch tube Q5 is connected to the discharge trigger module 11, the first end of the switch tube Q5 is connected to the photovoltaic input source 200 through the resistor R5, and the second end of the switch tube Q5 is used for grounding. Here, when the switch tube Q2 is turned on, the output voltage of the photovoltaic input source 200 flows into the control end of the switch tube Q5 through the switch tube Q2 to control the switch tube Q5 to be turned on, and at this time, the output voltage from the photovoltaic input source 200 flows into the ground through the resistor R5, thus discharging the electric energy in the photovoltaic input source 200. In addition, in order to prevent the erroneous conduction of the switch tube Q5, it is necessary to select the resistor R9 based on the on-voltage of the switch tube Q5.

[0036] 2-3, in some embodiments, the discharge trigger module 11 further includes a protection unit 113, a first end of which is connected to the trigger unit 112 and a control end of the discharge module 14, respectively, and a second end of which is connected to ground. The protection unit 113 is used to limit the voltage of the control end of the discharge module 14 while the discharge module 14 is turned on.

[0037] 4 to 6, the protection unit 113 is a diode ZD3, the cathode of which is connected to the control end of the switch tube Q5, and the anode of which is connected to ground. Here, the diode ZD3 is a clamp diode for the switch tube Q5, and the diode ZD3 ensures that the voltage at the control end of the switch tube Q5 is within a rated range.

[0038] 6, the locking module 12 includes a switch tube Q1 and a resistor R3, the control end of the switch tube Q1 is connected to the second end of the resistor R5, the first end of the switch tube Q1 is connected to the photovoltaic input source 200 through the resistor R3, and the second end of the switch tube Q1 is connected to the second end of the resistor R2. When the switch tube Q5 is turned on, the output voltage is also input to the control end of the switch tube Q1 through the resistor R5, which turns on the switch tube Q1. When the switch tube Q1 is turned on, the resistor R2 and the resistor R3 are connected in parallel, and divide the voltage together with the resistor R8 to keep the switch tube Q4 on, and thus keep the discharge module 14 discharging the electrical energy of the photovoltaic input source 200.

[0039] During the process in which the discharge module 14 continuously discharges the electric energy of the photovoltaic input source 200, the discharge unlock module 13 also receives the output voltage of the photovoltaic input source 200 in real time, and judges whether the output voltage of the photovoltaic input source 200 remains greater than the preset voltage even when the photovoltaic input source 200 is under load, and if the output voltage is greater than the preset voltage, obtains the period during which the output voltage is greater than the preset voltage and judges whether the period exceeds the preset time, and if the period during which the output voltage is greater than the preset voltage exceeds the preset time, the discharge unlock module 13 controls the discharge trigger module 11 to output a second control signal to stop the operation of the discharge module 14. In this way, by judging whether the photovoltaic voltage after the photovoltaic input source 200 discharges under load reaches the preset voltage, it is judged whether the photovoltaic voltage is a weak voltage. If the voltage is weak, the operation of the discharge module 14 is maintained to avoid wasting electrical energy by repeatedly activating the energy storage power source 100 when the photovoltaic voltage is weak, whereas if the voltage is not weak, i.e., the photovoltaic voltage is sufficient to charge the energy storage power source 100, the operation of the discharge module 14 is controlled to stop so that the photovoltaic input source 200 can supply power to the energy storage power source 100.

[0040] Here, as shown in Figures 4 to 6, the discharge unlock module 13 includes a diode ZD1, a diode ZD2, a capacitor C1, a switch tube Q3, a resistor R1 and a resistor R7, the cathode of the diode ZD1 is connected to the photovoltaic input source 200 via the resistor R1, the anode of the diode ZD1 is connected to the first end of the capacitor C1 and the cathode of the diode ZD2 respectively, the anode of the diode ZD2 is connected to the control end of the switch tube Q3, the first end of the switch tube Q3 is connected to the control end of the discharge trigger module 11, the second end of the switch tube Q3 is used for grounding, the second end of the capacitor C1 is grounded, and the resistor R7 and the capacitor C1 are connected in parallel. During the operation of the discharge module 14, the output voltage of the photovoltaic input source 200 is also output to the discharge unlock module 13, and after breaking down the diode ZD1 and the diode ZD2, it is input to the control end of the switch tube Q3, and turns on the switch tube Q3. When the switch tube Q3 is turned on, the control end of the switch tube Q4 is grounded through the switch tube Q3 and turns off, at this time, the discharge trigger module 11 stops working, and the discharge module 14 also stops working. Note that, since the capacitance of the capacitor C1 is much larger than the capacitance of the capacitor C2, when the photovoltaic input source 200 outputs a voltage, the switch tube Q4 needs to be turned on earlier than the switch tube Q3, so that the discharge trigger module 11 operates preferentially, and the resistor R5 is connected to the photovoltaic input source 200 first. As a result, at any time, the output voltage of the photovoltaic input source 200 is first weakly current-removed by the photovoltaic weak current removal circuit 10 until the output power of the photovoltaic input source 200 meets the preset power for starting up the BMS module 20.

[0041] The present application provides a photovoltaic weak current elimination circuit and an energy storage power supply, the photovoltaic weak current elimination circuit includes a discharge trigger module, a lock module, a discharge unlock module, and a discharge module, the discharge trigger module is respectively connected to the discharge module, the lock module, and the discharge unlock module, the discharge module, the discharge trigger module, and the discharge unlock module are all used to connect to a photovoltaic input source. The discharge trigger module is used to output a first control signal to the discharge module and control the discharge module to operate to discharge the energy of the photovoltaic input source when the output voltage of the photovoltaic input source is greater than a preset voltage, and after the operation of the discharge module, the lock module maintains the output of the first control signal by the discharge trigger module, so that the discharge module maintains operation. After the operation of the discharge module, if the output voltage of the photovoltaic input source is still greater than the preset voltage, the discharge unlock module controls the discharge trigger module to output a second control signal to stop the operation of the discharge module. According to this, when a photovoltaic input source is turned on and the output voltage of the photovoltaic input source, i.e., the photovoltaic voltage, reaches a preset voltage, the discharge trigger module and the lock module are operated to control the photovoltaic input source to perform on-load discharge. Whether the photovoltaic input source has a low voltage is determined by determining whether the photovoltaic voltage after the on-load discharge reaches a preset voltage. If the photovoltaic input source has a low voltage, the operation of the discharge module is maintained to avoid the waste of electrical energy caused by repeatedly starting the energy storage power source when the photovoltaic input source has a low voltage. On the other hand, if the photovoltaic input source is not a low voltage, i.e., the photovoltaic voltage is sufficient to charge the energy storage power source, the operation of the discharge module is controlled to be stopped, allowing the photovoltaic input source to supply power to the energy storage power source and improving the utilization rate of the photovoltaic input source.

[0042] It should be noted that the above-described device embodiments are merely illustrative, and the units described therein as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, i.e., they may be located at a location or distributed among multiple network units. Some or all of the modules may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

[0043] Finally, it should be noted that the above examples are only for illustrating the technical solutions of the present application, and are not intended to limit the same; in the belief of the present application, the technical features in the above examples or different examples can be combined, and steps can be implemented in any order; there are many other variations of different aspects of the present application as described above, which, for the sake of brevity, are not provided in detail; although the present application has been described in detail with reference to the above examples, those skilled in the art can still amend the technical solutions described in the above examples or make equivalent substitutions for some of the technical features therein, and it should be understood that these amendments and substitutions will not cause the essence of the corresponding technical solutions to depart from the scope of the technical solutions of the embodiments of the present application.

Claims

1. The device includes a discharge trigger module, a lock module, a discharge unlock module, and a discharge module; the discharge trigger module is connected to the discharge module, the lock module and the discharge unlock module respectively, the discharge module, the discharge trigger module and the discharge unlock module are all used to connect to a photovoltaic input source; the discharge trigger module is used to output a first control signal to the discharge module when the output voltage of the photovoltaic input source is greater than a preset voltage, and control the discharge module to operate and discharge the energy of the photovoltaic input source; The lock module is used to maintain the discharge trigger module outputting the first control signal after the discharge module is operated, so that the discharge module maintains operation; The photovoltaic weak current removal circuit is characterized in that the discharge unlock module is used to determine whether the output voltage of the photovoltaic input source is greater than a preset voltage after the operation of the discharge module, and when the output voltage of the photovoltaic input source is greater than the preset voltage, to control the discharge trigger module to output a second control signal to stop the operation of the discharge module.

2. The discharge trigger module includes a voltage division driving unit and a trigger unit; The voltage division driving unit is respectively connected to the photovoltaic input source, the discharge unlock module, the lock module and the trigger unit, and the trigger unit is respectively connected to the lock module and the discharge module; The voltage dividing drive unit is used for dividing the output voltage and inputting the divided output voltage to the trigger unit; The photovoltaic weak current removal circuit according to claim 1, characterized in that the trigger unit judges whether the divided output voltage reaches a trigger threshold to determine whether the output voltage is greater than the preset voltage, and outputs a first control signal to the discharge module when the divided output voltage reaches the trigger threshold.

3. The voltage divider driving unit includes a resistor R2, a resistor R8, and a capacitor C2; 3. The photovoltaic weak current removal circuit as claimed in claim 2, wherein a first end of the resistor R2 is connected to the photovoltaic input source, a second end of the resistor R2 is respectively connected to the discharge unlock module, the control end of the trigger unit and the first end of the resistor R8, and a second end of the resistor R8 is used for grounding, and the capacitor C2 and the resistor R8 are connected in parallel.

4. The trigger unit includes a switch tube Q2, a switch tube Q4, a resistor R4, a resistor R6, and a resistor R9; 4. The photovoltaic weak current elimination circuit as claimed in claim 3, characterized in that the control end of the switch tube Q4 is connected to the second end of the resistor R2, the first end of the switch tube Q4 is connected to the control end of the switch tube Q2 through the resistor R6, the second end of the switch tube Q4 is used for grounding, the control end of the switch tube Q2 is further connected to the locking module through the resistor R6, the first end of the switch tube Q2 is connected to the photovoltaic input source through the resistor R4, and the second end of the switch tube Q2 is grounded through the resistor R9.

5. The discharge module includes a resistor R5 and a switch tube Q5; 2. The photovoltaic weak current elimination circuit as claimed in claim 1, wherein the control end of said switch tube Q5 is connected to said discharge trigger module, a first end of said switch tube Q5 is connected to said photovoltaic input source through said resistor R5, and a second end of said switch tube Q5 is used for grounding.

6. The photovoltaic weak current removal circuit according to claim 2, wherein the lock module is used to adjust the ratio of the divided output voltage so as to maintain the discharge trigger module outputting the first control signal after the discharge module is operated.

7. The locking module includes a switch tube Q1 and a resistor R3; 7. The photovoltaic weak current elimination circuit according to claim 6, wherein the control end of the switch tube Q1 is connected to the trigger unit, the first end of the switch tube Q1 is connected to the first end of the voltage divider driving unit through the resistor R3, and the second end of the switch tube Q1 is connected to the second end of the voltage divider driving unit.

8. The photovoltaic weak current removal circuit of claim 1, characterized in that after the operation of the discharge module, the discharge unlock module determines whether the output voltage is greater than the predetermined voltage and whether the period during which the output voltage is greater than the predetermined voltage exceeds the predetermined time, and controls the discharge trigger module to output the second control signal if the period during which the output voltage is greater than the predetermined voltage exceeds the predetermined time.

9. The discharge unlock module includes: a diode ZD1, a diode ZD2, a capacitor C1, a switch tube Q3, a resistor R1 and a resistor R7; 9. The photovoltaic weak current removal circuit as claimed in claim 8, wherein the cathode of the diode ZD1 is connected to the photovoltaic input source through the resistor R1, the anode of the diode ZD1 is respectively connected to the first end of the capacitor C1 and the cathode of the diode ZD2, the anode of the diode ZD2 is connected to the control end of the switch tube Q3, the first end of the switch tube Q3 is connected to the control end of the discharge trigger module, the second end of the switch tube Q3 is grounded, the second end of the capacitor C1 is grounded, and the resistor R7 and the capacitor C1 are connected in parallel.

10. A BMS module; Batteries and and a photovoltaic weak current removal circuit according to any one of claims 1 to 9, wherein the BMS module is connected to the discharge module and the battery, respectively.

1. An energy storage power source comprising:

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