Charging circuit and device of multifunctional self-adaptive photovoltaic power supply controller

Abstract

The utility model discloses a charging circuit and device of a multifunctional adaptive photovoltaic power controller. The charging circuit and device of the multifunctional adaptive photovoltaic power controller are used for the multifunctional adaptive photovoltaic power controller. The circuit comprises a signal sampling circuit, an MOS tube driving circuit, a BUCK step-down circuit and a direct current conversion circuit, the signal sampling circuit is connected with the direct current conversion circuit through the MOS tube driving circuit and the BUCK step-down circuit in sequence to supply power to electric equipment, and the signal sampling circuit collects the voltage difference of the power output end of a photovoltaic panel in a set period to supply power to the electric equipment. And the magnitude of the output pulse modulation signal PWM is controlled, so that the magnitude of the output voltage of the BUCK step-down circuit is controlled, and the tracking of the maximum power point of the power output end of the photovoltaic panel is realized. According to the invention, the optimal output effect of the output electric quantity of the photovoltaic panel can be realized, the charging efficiency of the equipment is maximized, and the electric equipment can be stably charged.

Description

Technical Field

[0001] The present disclosure generally relates to the technical field of photovoltaic power generation equipment, and in particular to a charging circuit and device of a multifunctional adaptive photovoltaic power controller for fast charging using photovoltaic panels of a photovoltaic backpack. Background Art

[0002] The photovoltaic backpack is composed of a photovoltaic panel and a DC buck module. Conventional DC buck modules cannot be well adapted to photovoltaic panels. When the light changes or the light is weak, the DC buck module pulls down the voltage at both ends of the photovoltaic panel. The DC buck module will hiccup after undervoltage protection. At this time, charging of mobile phones and other electronic products will be intermittent, the charging experience is extremely poor, and the photoelectric conversion efficiency is extremely low. This is a specific problem in the field of mobile, low-power photovoltaic power generation.

[0003] Therefore, the existing technology needs to be improved. Summary of the invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide a charging circuit and device of a multifunctional adaptive photovoltaic power controller that can meet the current specific needs for fast charging of photovoltaic backpacks.

[0005] Based on one aspect of the embodiment of the utility model, the embodiment of the present application provides a charging circuit of a multifunctional adaptive photovoltaic power controller, including:

[0006] Signal sampling circuit, MOS tube driving circuit, BUCK step-down circuit, DC conversion circuit;

[0007] The signal sampling circuit is connected to the MOS tube driving circuit, the signal sampling circuit is connected to the power output terminal of the photovoltaic panel, and collects the voltage parameters output by the photovoltaic panel, and outputs a pulse modulation signal PWM to the MOS tube driving circuit;

[0008] The MOS tube driving circuit is connected to the signal sampling circuit and the BUCK buck circuit. The MOS tube driving circuit processes the pulse modulation signal PWM output by the signal sampling circuit to make the level of the pulse modulation signal PWM consistent with the level of the power output end of the photovoltaic panel, and outputs the processed pulse modulation signal PWM to the BUCK buck circuit to control the MOS tube switch state of the BUCK buck circuit;

[0009] The BUCK buck circuit is connected to the MOS tube drive circuit, the DC conversion circuit, and the power output end of the photovoltaic panel. The BUCK buck circuit controls the MOS tube switch of the BUCK buck circuit according to the level signal sent by the MOS tube drive circuit, so as to realize the power output of the photovoltaic panel;

[0010] The signal sampling circuit controls the output pulse modulation signal PWM by collecting the voltage difference of the power output terminal of the photovoltaic panel within a set period, thereby controlling the output voltage of the BUCK step-down circuit and tracking the maximum power point of the power output terminal of the photovoltaic panel;

[0011] The DC conversion circuit is connected to the BUCK step-down circuit, and is used to receive the photovoltaic panel output power processed by the BUCK step-down circuit, and convert the voltage into corresponding parameters according to application requirements.

[0012] In another embodiment, the MOS transistor driving circuit includes a first transistor, a first capacitor, and a second capacitor;

[0013] The first capacitor is connected to the base of the first transistor, the second capacitor is connected to the base and emitter of the first transistor, the first capacitor is used to accelerate the opening of the first transistor, and the second capacitor is used to accelerate the turning off of the first transistor.

[0014] In another embodiment, the BUCK step-down circuit includes a first MOS tube, a first diode, and a second diode;

[0015] The first diode is connected to the gate and source of the first MOS tube, and the second diode is reversely connected to the source and drain of the first MOS tube. The first diode is used to clamp the gate and source of the first MOS tube to prevent the instantaneous voltage from exceeding the gate-source driving voltage of the first MOS tube and damaging the first MOS tube. The second diode is used to protect the first MOS tube.

[0016] In another embodiment, the BUCK step-down circuit further includes a first resistor and a second resistor;

[0017] The first resistor is connected in parallel with the first diode, and the second resistor is connected to the gate of the first MOS tube and the MOS tube driving circuit;

[0018] The first resistor and the second resistor together adjust the gate potential of the first MOS tube.

[0019] In another embodiment, the signal sampling circuit collects a first voltage and a second voltage at a power output terminal of the photovoltaic panel within a set period, and calculates a voltage difference between the first voltage and the second voltage;

[0020] If the voltage difference between the first voltage and the second voltage is less than a set threshold, increasing the output level of the pulse modulation signal PWM;

[0021] If the voltage difference between the first voltage and the second voltage is greater than a set threshold, the output pulse modulation signal PWM level is reduced.

[0022] Based on another aspect of the embodiments of the utility model, a charging device is disclosed, which includes the charging circuit of the multifunctional adaptive photovoltaic power supply controller provided by each embodiment of the utility model.

[0023] In the embodiment of the present application, by setting a signal sampling circuit, a MOS tube driving circuit, a BUCK buck circuit, and a DC conversion circuit, the signal sampling circuit is connected to the DC conversion circuit through the MOS tube driving circuit and the BUCK buck circuit in turn to realize power supply to the electrical equipment, and the signal sampling circuit controls the output pulse modulation signal PWM by collecting the voltage difference at the power output end of the photovoltaic panel within a set period, thereby controlling the output voltage of the BUCK buck circuit to realize tracking of the maximum power point at the power output end of the photovoltaic panel. The present application can achieve the best output effect of the output power of the photovoltaic panel, maximize the charging efficiency of the equipment, and can stably charge the electrical equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0025] Figure 1 It is a structural schematic diagram of a charging circuit of a multifunctional adaptive photovoltaic power controller provided by an embodiment of the present application;

[0026] Figure 2 It is a circuit diagram of a MOS tube driving circuit of a charging circuit of a multifunctional adaptive photovoltaic power controller provided by an embodiment of the present application;

[0027] Figure 3 It is a circuit diagram of a BUCK step-down circuit of a charging circuit of a multifunctional adaptive photovoltaic power controller provided by another embodiment of the present application;

[0028] Figure 4 This is a schematic diagram of maximum power point tracking of a photovoltaic panel provided in yet another embodiment of the present application.

[0029] In the figure: 100 signal sampling circuit, 200 MOS tube driving circuit, 300 BUCK step-down circuit, 400 DC conversion circuit. DETAILED DESCRIPTION

[0030] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant utility model, rather than to limit the utility model. It is also necessary to explain that, for ease of description, only the parts related to the utility model are shown in the accompanying drawings.

[0031] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0032] like Figure 1 As shown, the charging circuit of the multifunctional adaptive photovoltaic power controller of the embodiment of the present application includes:

[0033] Signal sampling circuit 100, MOS tube driving circuit 200, BUCK step-down circuit 300, DC conversion circuit 400;

[0034] The signal sampling circuit 100 is connected to the MOS tube driving circuit 200. The signal sampling circuit 100 is connected to the power output terminal of the photovoltaic panel, collects the voltage parameters output by the photovoltaic panel, and outputs a pulse modulation signal PWM to the MOS tube driving circuit 200.

[0035] The MOS tube driving circuit 200 is connected to the signal sampling circuit 100 and the BUCK buck circuit 300. The MOS tube driving circuit 200 processes the pulse modulation signal PWM output by the signal sampling circuit 100 to make the level of the pulse modulation signal PWM consistent with the level of the power output terminal of the photovoltaic panel, and outputs the processed pulse modulation signal PWM to the BUCK buck circuit 300 to control the MOS tube switch state of the BUCK buck circuit 300;

[0036] The BUCK buck circuit 300 is connected to the MOS tube driving circuit 200 and the DC conversion circuit 400, and is connected to the power output end of the photovoltaic panel. The BUCK buck circuit 300 controls the MOS tube switch of the BUCK buck circuit 300 according to the level signal sent by the MOS tube driving circuit 200, so as to realize the power output of the photovoltaic panel.

[0037] The signal sampling circuit 100 controls the output pulse modulation signal PWM by collecting the voltage difference of the power output terminal of the photovoltaic panel within a set period, thereby controlling the output voltage of the BUCK step-down circuit 300 to track the maximum power point of the power output terminal of the photovoltaic panel;

[0038] The DC conversion circuit 400 is connected to the BUCK buck circuit 300, and is used to receive the photovoltaic panel output power processed by the BUCK buck circuit 300, and convert the voltage into corresponding parameters according to application requirements.

[0039] Specifically, in actual implementation, the signal sampling circuit 100 uses a single-chip microcomputer to collect the voltage parameters of the output end of the photovoltaic panel in real time, and outputs a pulse modulation signal PWM through program control. The principle of the signal sampling circuit 100 tracking the maximum power point of the power output end of the photovoltaic panel is as follows: after the system is powered on, the power output end of the photovoltaic panel outputs a voltage, the signal acquisition circuit 100 collects the voltage Ut0 of the power output end of the photovoltaic panel, and then outputs it to the MOS tube driving circuit 200 in a constant pulse modulation signal PWM according to the parameters of the voltage Ut0. Within a set period, the signal sampling circuit 100 collects the voltage Ut0 of the power output end of the photovoltaic panel again. Voltage Ut1, then the voltage change ΔUp collected in these two times is ΔUp=Ut1-Ut0, and the floating coefficient is set to K. If |ΔUp|<=K, it means that the output power of the power output end of the photovoltaic panel can carry the circuit load at this time, and the pulse modulation signal PWM is further increased at this time; if |ΔUp|>K, it means that the output power of the power output end of the photovoltaic panel is not enough to support the circuit load, which may cause the voltage collapse at both ends of the photovoltaic panel. At this time, the pulse modulation signal PWM should be reduced. The signal acquisition circuit 100 can track the maximum power point of the photovoltaic panel by judging ΔUp, that is, the maximum power point tracking is completed by the constant voltage method.

[0040] Specifically, the function of the MOS tube driving circuit 200 is to amplify the level of the pulse modulation signal PWM output by the signal sampling circuit 100, and can convert the level of the pulse modulation signal PWM output by the signal sampling circuit 100 into a level close to the power output end of the photovoltaic panel, and output it to the gate of the MOS tube of the BUCK step-down circuit 300, so as to drive the MOS tube so that the MOS tube works in a switching state.

[0041] like Figure 2 As shown, the MOS transistor driving circuit 200 includes a first transistor Q1, a first capacitor C1, and a second capacitor C2;

[0042] The first capacitor C1 is connected to the base of the first transistor Q1, and the second capacitor C2 is connected to the base and emitter of the first transistor Q1. The first capacitor C1 is used to accelerate the opening of the first transistor Q1, and the second capacitor C2 is used to accelerate the closing of the first transistor Q1.

[0043] like Figure 3 As shown, the BUCK step-down circuit 300 includes a first MOS tube Q2, a first diode D1, and a second diode D2;

[0044] The first diode D1 is connected to the gate and source of the first MOS transistor Q2, and the second diode D2 is reversely connected to the source and drain of the first MOS transistor Q2. The first diode D1 is used to clamp the gate and source of the first MOS transistor Q2 to prevent the instantaneous voltage from exceeding the gate-source driving voltage of the first MOS transistor Q2 and damaging the first MOS transistor Q2. The second diode D2 is used to protect the first MOS transistor Q2.

[0045] The BUCK step-down circuit 300 further includes a first resistor R1 and a second resistor R2;

[0046] The first resistor R1 is connected in parallel with the first diode D1, and the second resistor R2 is connected to the gate of the first MOS transistor Q2 and the MOS transistor driving circuit 200;

[0047] The first resistor R1 and the second resistor R2 together adjust the gate potential of the first MOS transistor Q2.

[0048] Specifically, the first resistor R1 and the second resistor R2 adjust the gate potential of the first MOS transistor Q2 on a path. When the first transistor Q1 is turned off, the gate voltage VG=source voltage VS, and the gate-source voltage difference is: VGS=VG-VS=0V. When the first MOS transistor Q2 is turned on, the gate voltage: VG=Vin×{R2 / (R1+R2)}, the source voltage VS=input voltage Vin, then the gate-source voltage difference is: VGS=Vin×{R2 / (R1+R2)}-Vin. When the first resistor R1 is large and the second resistor R2 is small, the gate-source voltage difference VGS≈input voltage Vin.

[0049] The signal sampling circuit 100 collects a first voltage and a second voltage at the power output terminal of the photovoltaic panel within a set period, and calculates a voltage difference between the first voltage and the second voltage;

[0050] If the voltage difference between the first voltage and the second voltage is less than a set threshold, increasing the output level of the pulse modulation signal PWM;

[0051] If the voltage difference between the first voltage and the second voltage is greater than a set threshold, the output pulse modulation signal PWM level is reduced.

[0052] Specifically, Figure 4 As shown, each photovoltaic panel is produced with a maximum power tracking point V MPPT In an embodiment of the present application, the maximum power point of the photovoltaic panel is tracked by a constant voltage method. Figure 4 In, V MPIndicates the maximum power point, the parabola labeled α is the IV relationship curve of the photovoltaic panel output, and the parabola labeled β is the PV relationship curve. Figure 4 In, V MP The maximum power is at the point where the output voltage of the photovoltaic panel is collected through the voltage sampling circuit 100. At this time, the pulse modulation signal PWM is increased to ensure that the maximum power provided by the output end of the photovoltaic panel can be fully applied; if the voltage decreases and the power also decreases, it means that the maximum power point is shifted to the left at this time, and the pulse modulation signal PWM needs to be reduced; if the voltage increases but the power decreases, it means that the maximum power point is shifted to the right, and the pulse modulation signal PWM needs to be further increased. In this way, tracking is achieved near the maximum power point, thereby achieving adaptive tracking and matching of the maximum power point.

[0053] By collecting the voltage difference between the first voltage and the second voltage at the power output end of the photovoltaic panel through the signal sampling circuit 100, the maximum power point of the photovoltaic panel can be tracked, thereby realizing adaptive tracking and matching of the maximum power point. In situations where the light intensity is weak or the light changes greatly, the back-end module can be used to stably charge the electrical equipment through buffer matching.

[0054] The units or modules involved in the embodiments described in the present application may be implemented by software or hardware. The units or modules described may also be arranged in a processor. The names of these units or modules do not constitute limitations on the units or modules themselves in certain circumstances.

[0055] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the utility model involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the concept of the utility model. For example, the above features are replaced with the technical features with similar functions disclosed in the present application (but not limited to) by each other to form a technical solution.

Claims

1. A charging circuit of a multifunctional adaptive photovoltaic power controller, characterized in that: include: Signal sampling circuit, MOS tube driving circuit, BUCK step-down circuit, DC conversion circuit; The signal sampling circuit is connected to the MOS tube driving circuit, the signal sampling circuit is connected to the power output terminal of the photovoltaic panel, and collects the voltage parameters output by the photovoltaic panel, and outputs a pulse modulation signal PWM to the MOS tube driving circuit; The MOS tube driving circuit is connected to the signal sampling circuit and the BUCK buck circuit. The MOS tube driving circuit processes the pulse modulation signal PWM output by the signal sampling circuit to make the level of the pulse modulation signal PWM consistent with the level of the power output end of the photovoltaic panel, and outputs the processed pulse modulation signal PWM to the BUCK buck circuit to control the MOS tube switch state of the BUCK buck circuit; The BUCK buck circuit is connected to the MOS tube drive circuit, the DC conversion circuit, and the power output end of the photovoltaic panel. The BUCK buck circuit controls the MOS tube switch of the BUCK buck circuit according to the level signal sent by the MOS tube drive circuit, so as to realize the power output of the photovoltaic panel; The signal sampling circuit controls the output pulse modulation signal PWM by collecting the voltage difference of the power output terminal of the photovoltaic panel within a set period, thereby controlling the output voltage of the BUCK step-down circuit and tracking the maximum power point of the power output terminal of the photovoltaic panel; The DC conversion circuit is connected to the BUCK step-down circuit, and is used to receive the photovoltaic panel output power processed by the BUCK step-down circuit, and convert the voltage into corresponding parameters according to application requirements.

2. The charging circuit of the multifunctional adaptive photovoltaic power controller according to claim 1 is characterized in that: The MOS tube driving circuit includes a first transistor, a first capacitor, and a second capacitor; The first capacitor is connected to the base of the first transistor, the second capacitor is connected to the base and emitter of the first transistor, the first capacitor is used to accelerate the opening of the first transistor, and the second capacitor is used to accelerate the turning off of the first transistor.

3. The charging circuit of the multifunctional adaptive photovoltaic power controller according to claim 1 is characterized in that: The BUCK step-down circuit includes a first MOS tube, a first diode, and a second diode; The first diode is connected to the gate and source of the first MOS tube, and the second diode is reversely connected to the source and drain of the first MOS tube. The first diode is used to clamp the gate and source of the first MOS tube to prevent the instantaneous voltage from exceeding the gate-source driving voltage of the first MOS tube and damaging the first MOS tube. The second diode is used to protect the first MOS tube.

4. The charging circuit of the multifunctional adaptive photovoltaic power controller according to claim 3 is characterized in that: The BUCK step-down circuit also includes a first resistor and a second resistor; The first resistor is connected in parallel with the first diode, and the second resistor is connected to the gate of the first MOS tube and the MOS tube driving circuit; The first resistor and the second resistor together adjust the gate potential of the first MOS tube.

5. The charging circuit of the multifunctional adaptive photovoltaic power controller according to claim 1, characterized in that: The signal sampling circuit collects a first voltage and a second voltage at the power output terminal of the photovoltaic panel within a set period, and calculates a voltage difference between the first voltage and the second voltage; If the voltage difference between the first voltage and the second voltage is less than a set threshold, increasing the output level of the pulse modulation signal PWM; If the voltage difference between the first voltage and the second voltage is greater than a set threshold, the output pulse modulation signal PWM level is reduced.

6. A charging device, characterized in that: The device comprises a charging circuit of the multifunctional adaptive photovoltaic power controller according to any one of claims 1 to 5.

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