Photovoltaic weak current removal circuit and energy storage power supply

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 elimination circuit and energy storage power supply," the entire contents of which are incorporated herein by reference.

[0002] This application relates to the technical field of power supply 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 shade from trees or dark clouds during solar panel operation, 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 within the system, and the system will immediately shut down. In this way, the energy storage power supply will keep alternating between being started and being shut down, making the system operation unstable and significantly 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 causes the energy storage power supply to operate unstable and suffer from a large life loss.

[0005] In order to solve the above-mentioned technical problems, one 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, 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 when the output voltage of the photovoltaic input source is greater than a preset voltage, and control the discharge module to operate and discharge energy of the photovoltaic input source; the locking module is used to keep the discharge trigger module outputting the first control signal after the discharge module is activated, so that the discharge module maintains its operation; The discharge unlock module determines whether the output voltage of the photovoltaic input source is greater than a preset voltage after the discharge module operates, and controls the discharge trigger module to output a second control signal if the output voltage of the photovoltaic input source is greater than the preset voltage, thereby providing 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 dividing drive 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 to divide the output voltage and input 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 to output a first control signal to the discharge module when the divided output voltage reaches the trigger threshold.

[0007] The voltage dividing drive 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 grounded, 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 may be connected to the second end of the resistor R2, the first end of the switch tube Q4 may be connected to the control end of the switch tube Q2 via the resistor R6, the second end of the switch tube Q4 may be used to ground, the control end of the switch tube Q2 may be further connected to the locking module via the resistor R6, the first end of the switch tube Q2 may be connected to the photovoltaic input source via the resistor R4, and the second end of the switch tube Q2 may be grounded via 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, the first end of the switch tube Q5 may be connected to the photovoltaic input source via the resistor R5, and the 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 activated.

[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 be configured to determine, after the operation of the discharge module, whether the output voltage is greater than the preset voltage and whether the period during which the output voltage is greater than the preset voltage exceeds a preset time, and to control the discharge trigger module to output the second control signal if the period during which the output voltage is greater than the preset voltage exceeds the preset time.

[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 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, 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.

[0014] In order to solve the above-mentioned technical problems, another technical solution adopted in the embodiments of the present 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] Unlike the related art, in the photovoltaic weak current elimination circuit and 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 to operate the discharge module to discharge energy of the photovoltaic input source when the output voltage of the photovoltaic input source is greater than a preset voltage, after the discharge module operates, the lock module maintains the output of the first control signal by the discharge trigger module to keep the discharge module operating, and after the discharge module operates, 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 predetermined voltage, the discharge trigger module and the lock module operate to control the photovoltaic input source to perform on-load discharge. Whether the photovoltaic voltage is weak is determined by determining whether the photovoltaic voltage after the photovoltaic input source has reached the predetermined voltage. If the photovoltaic voltage is weak, the discharge module continues to operate to avoid wasting electrical energy by repeatedly activating the energy storage power supply when the photovoltaic voltage is weak. However, if the photovoltaic voltage is not weak, i.e., if the photovoltaic voltage is sufficient to charge the energy storage power supply, the discharge module is controlled to stop operating, allowing the photovoltaic input source to supply power to the energy storage power supply and improving the utilization rate of the photovoltaic input source. [Brief explanation of the drawings]

[0016] One or more embodiments are illustratively described in the accompanying drawings, which are not intended to be limiting, but rather to illustrate, without limitation, the embodiments, in which like reference numerals represent similar elements and in which the figures are not to scale unless otherwise specified. [Figure 1] 1 is an application scenario of an energy storage power supply according to an embodiment of the present application. [Figure 2] 1 is a block diagram showing the configuration of a photovoltaic weak current removal circuit according to an embodiment of the present application; [Figure 3] FIG. 10 is a block diagram showing the configuration of a photovoltaic weak current removing circuit according to another embodiment of the present application. [Figure 4] 1 is a circuit diagram of a photovoltaic weak current removal circuit according to an embodiment of the present application; [Figure 5] FIG. 10 is a circuit diagram of a photovoltaic weak current removal circuit according to another embodiment of the present application. [Figure 6] FIG. 10 is a circuit diagram of a photovoltaic weak current removal circuit according to yet another embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0017] In order to make the purpose, technical solution and advantages of the present application clearer, 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 there is a contradiction, the features in the embodiments of the present application can 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 module division in the schematic diagram of the device may be different from the division, or the steps shown or described 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 scope of this application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0020] Referring to FIG. 1 , which illustrates an application scenario of an energy storage power supply according to an embodiment of the present application, the application scenario includes an energy storage power supply 100 and a photovoltaic power input source 200, which are connected to each other. 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 supply 100, and store the electrical energy in the energy storage power supply 100. Here, as shown in FIG. 1 , the energy storage power supply 100 includes a photovoltaic weak current removal circuit 10, a BMS module 20, and a battery 30, both of which are connected to the photovoltaic weak current removal circuit 100, 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 the electrical energy to the photovoltaic weak current removal circuit 10. When the photovoltaic weak current removal circuit 10 receives the electrical energy, it determines whether to discharge the electrical energy based on the electrical energy. If the electrical energy is not to be 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 electrical energy in the battery 30. When the electrical energy is to be discharged, the photovoltaic weak current removal circuit 10 discharges the photovoltaic input source 200, thereby avoiding repeated activation of the BMS module 20 when the photovoltaic input source 200 has a weak voltage and improving the stability of the energy storage power supply 100. It should be noted that the BMS module 20 includes a built-in 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 lower 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 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. The discharge trigger module 11 is connected to the discharge module 14, the lock module 12, and the discharge unlock module 13, respectively, 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 sunlight, and the discharge trigger module 11 receives the output voltage and determines whether the output voltage exceeds a preset voltage. If the output voltage is greater than the preset voltage, the discharge trigger module 11 outputs a first control signal to the discharge module 14 to control the discharge module 14 to start operating, causing the discharge module 14 to discharge energy from the photovoltaic input source 200. Here, the preset voltage may be the startup voltage of the BMS module 20, or may be a voltage value designed based on the startup voltage and safety redundancy.

[0023] Here, as shown in FIG. 2, the discharge trigger module 11 includes a voltage dividing unit 111 and a trigger unit 112, the voltage dividing 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-dividing 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 determines whether the divided output voltage reaches a trigger threshold to determine 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 removal circuit according to an 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, 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, 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 resistors R2 and 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 via the resistor R6, the second end of the switch tube Q4 is used to ground, the control end of the switch tube Q2 is further connected to the locking module 12 via the resistor R6, the first end of the switch tube Q2 is connected to the photovoltaic input source 200 via the resistor R4, and the second end of the switch tube Q2 is grounded via the resistor R9. When the switch tube Q4 receives the divided output voltage, it determines whether the divided output voltage is greater than a trigger threshold. If the divided output voltage is greater than the trigger threshold, the switch tube Q4 turns on with the divided output voltage. At this time, the switch tube Q2 also turns on with its control end connected to ground via a resistor R6. When the switch tube Q2 turns on, it outputs a first control signal to the discharge module 14, causing the discharge module 14 to discharge the electrical energy of the photovoltaic input source 200. In order to ensure the withstand voltage and power consumption of the resistor R4, the type of the resistor R4 should be selected based on the highest voltage of the photovoltaic input source 200.

[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 connected to the locking module 12 and the control end of the switch tube Q2 via the resistor R6, respectively. 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 discharge module 14 is activated, thereby maintaining the operation of the discharge module 14. In one embodiment, after the discharge module 14 starts operating 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, since the discharge module is driven and operated based on the first control signal output by the discharge trigger module, the above-mentioned "after the discharge module is activated" 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. When light irradiation is insufficient, i.e., when the photovoltaic input source 200 has a weak voltage, its no-load voltage can reach the startup voltage of the BMS module 20, e.g., 12 V. However, when a load is connected to the photovoltaic power input source 200, the output voltage of the photovoltaic power input source 200 decreases. Therefore, after the discharge module 14 is activated, i.e., after a load is applied to the photovoltaic power input source 200, the locking module 12 must maintain the discharge trigger module 11 outputting the first control signal to keep the discharge module 14 turned on. After the discharge module 14 is turned on, it is again determined whether the output voltage of the photovoltaic power input source 200 is greater than the preset voltage, and further determined whether the output voltage 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 switch tube Q4 is turned on, switch tubes Q1 and Q2 are also turned on. As a result of switch tube Q1 being turned on, resistors R2 and R3 are connected in parallel and divide the voltage together with resistor R8, increasing the input voltage of switch tube Q4. This ensures that the input voltage of switch tube Q4 remains greater than the trigger threshold after switch tube Q2 outputs a first control signal to control discharge module 14 to operate, thereby maintaining switch tube Q4 on and thus maintaining discharge module 14 discharging electrical energy from photovoltaic input source 200. Here, the resistance value of resistor R3 is smaller than that of resistor R2. Note that since the discharge module 14 is connected to photovoltaic input source 200, when the discharge module 14 is turned on, the output voltage of the photovoltaic input source 200 decreases. In this case, by providing the switch tube Q1 and resistor R3, when the discharge module 14 is turned on, the resistors R2 and R3 are connected in parallel to reduce the divided voltage across the resistor R2, and the voltage across the resistor R8 can accommodate the continuous on of the switch tube Q4. This prevents the discharge trigger module 11 from repeatedly switching between operating states at low voltages, thereby improving the reliability of the photovoltaic weak current elimination circuit 10.

[0031] 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 via 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 via the resistor R6 and turned on. At this time, the resistors R3 and R2 are connected in parallel to reduce the divided voltage across the resistor R2, thereby keeping the switch tube Q4 on and thus keeping the discharge module 14 discharging 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 Figure 3, which is a structural 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, and 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, and 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] 6, the voltage dividing 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 unit 111 is the same as that shown in FIG.

[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 grounded, 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. 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] 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 via the resistor R5, and the second end of the switch tube Q5 is grounded. 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 via the switch tube Q2, controlling the switch tube Q5 to turn on. At this time, the output voltage from the photovoltaic input source 200 flows to ground via the resistor R5, thereby discharging the electrical energy in the photovoltaic input source 200. To prevent erroneous conduction of the switch tube Q5, the resistor R9 must be selected based on the on-voltage of the switch tube Q5.

[0036] 2-3, 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, and a second end of which is connected to ground. The protection unit 113 is used to limit the voltage at 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, where 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 the rated range.

[0038] 6, the locking module 12 includes a switch tube Q1 and a resistor R3, the control end of which is connected to the second end of the resistor R5, the first end of which is connected to the photovoltaic input source 200 via the resistor R3, and the second end of which 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 via the resistor R5, turning on the switch tube Q1. When the switch tube Q1 is turned on, the resistors R2 and R3 are connected in parallel and divide the voltage together with the resistor R8, keeping the switch tube Q4 on, which in turn keeps the discharge module 14 discharging the electrical energy of the photovoltaic input source 200.

[0039] While the discharge module 14 is continuously discharging the electrical 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 determines 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. If the output voltage is greater than the preset voltage, the discharge unlock module 13 obtains the period during which the output voltage is greater than the preset voltage and determines whether the period exceeds the preset time. 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 determining whether the photovoltaic voltage of the photovoltaic input source 200 after discharge under load reaches the preset voltage, it is determined whether the photovoltaic voltage is a weak voltage. If the voltage is weak, the discharge module 14 is maintained in operation to avoid wasting electrical energy by repeatedly activating the energy storage power supply 100 when the photovoltaic voltage is weak, while if the voltage is not weak, i.e., the photovoltaic voltage is sufficient to charge the energy storage power supply 100, the discharge module 14 is controlled to stop operating so that the photovoltaic input source 200 can supply power to the energy storage power supply 100.

[0040] 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, 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 grounded, the second end of the capacitor C1 is grounded, and the resistor R7 and the capacitor C1 are connected in parallel. While the discharge module 14 is operating, the output voltage of the photovoltaic input source 200 is also output to the discharge unlock module 13, which breaks down the diodes ZD1 and ZD2 and then inputs it to the control end of the switch tube Q3, turning it on. When the switch tube Q3 is turned on, the control end of the switch tube Q4 is grounded via the switch tube Q3 and turns it off. At this time, the discharge trigger module 11 stops operating, and therefore the discharge module 14 also stops operating. Note that because the capacitance of the capacitor C1 is much larger than that of the capacitor C2, when the photovoltaic input source 200 outputs a voltage, the switch tube Q4 must be turned on before the switch tube Q3, so that the discharge trigger module 11 operates first, and the resistor R5 is first connected to the photovoltaic input source 200. 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 including 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 lock module, and the discharge unlock module, respectively, and the discharge module, the discharge trigger module, and the discharge unlock module being all used to connect to a photovoltaic input source. When the output voltage of the photovoltaic input source is greater than a predetermined voltage, the discharge trigger module outputs a first control signal to the discharge module to operate the discharge module to discharge energy from the photovoltaic input source. After the discharge module operates, the lock module maintains the output of the first control signal from the discharge trigger module, causing the discharge module to continue operating. If the output voltage of the photovoltaic input source is still greater than the predetermined voltage after the discharge module operates, 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 predetermined voltage, the discharge trigger module and the lock module operate to control the photovoltaic input source to perform on-load discharge. Whether the photovoltaic voltage is weak is determined by determining whether the photovoltaic voltage after the photovoltaic input source has reached the predetermined voltage. If the photovoltaic voltage is weak, the discharge module continues to operate to avoid wasting electrical energy by repeatedly activating the energy storage power supply when the photovoltaic voltage is weak. However, if the photovoltaic voltage is not weak, i.e., if the photovoltaic voltage is sufficient to charge the energy storage power supply, the discharge module is controlled to stop operating, allowing the photovoltaic input source to supply power to the energy storage power supply 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 certain location or distributed across 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 present 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 spirit 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 deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A photovoltaic weak current elimination circuit is included, 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 connected to the discharge module, the lock module and the discharge unlock module respectively, 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 when the output voltage of the photovoltaic input source is greater than a preset voltage, and control the discharge module to operate and discharge energy of the photovoltaic input source; the locking module is used to keep the discharge trigger module outputting the first control signal after the discharge module is activated, so that the discharge module maintains its operation; 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 to control the discharge trigger module to output a second control signal to stop the operation of the discharge module if the output voltage of the photovoltaic input source is greater than the preset voltage.

2. The discharge trigger module includes a voltage division driving unit and a trigger unit; The voltage dividing drive 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 to divide the output voltage and input the divided output voltage to the trigger unit; 2. The energy storage power supply of claim 1, wherein the trigger unit determines 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 dividing drive unit includes a resistor R2, a resistor R8, and a capacitor C2; 3. The energy storage power supply of 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, a control end of the trigger unit, and a first end of the resistor R8, and a second end of the resistor R8 is grounded, 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 energy storage power supply of claim 3, wherein 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 connected to ground, 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 energy storage power supply of claim 1, wherein the control end of the switch tube Q5 is connected to the discharge trigger module, the first end of the switch tube Q5 is connected to the photovoltaic input source through the resistor R5, and the second end of the switch tube Q5 is grounded.

6. 3. The energy storage power supply of claim 2, wherein the locking module is used to adjust the divided output voltage so as to maintain the discharge trigger module outputting the first control signal after the discharge module is activated.

7. The locking module includes a switch tube Q1 and a resistor R3; 7. The energy storage power supply of 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 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.

8. 2. The energy storage power supply of claim 1, wherein the discharge unlock module determines whether the output voltage is greater than the preset voltage and whether a period during which the output voltage is greater than the preset voltage exceeds a preset time after the discharge module operates, and controls the discharge trigger module to output the second control signal when the period during which the output voltage is greater than the preset voltage exceeds the preset 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 energy storage power supply of 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 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 connected to ground, the second end of the capacitor C1 is grounded, and the resistor R7 and the capacitor C1 are connected in parallel.

10. A battery management system module; a battery, wherein the battery management system modules are connected to the discharge module and the battery, respectively.

2. The energy storage power supply of claim 1.

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