Large dynamic range solar maximum charging current tracking collector

Abstract

The present invention discloses a large dynamic range solar maximum charging current tracking collector, which relates to the field of solar energy collection technology, including an input light energy interface, an energy collection matrix, a control module and an energy output management module, wherein the control module is connected to the input light energy interface, the energy collection matrix and the energy output management module respectively; the input light energy interface is used to access the electric energy generated by the solar cell; the energy collection matrix includes at least two collection circuits with different powers, and the collection circuit is used to transfer the electric energy; the control module is used to select the collection circuit from the energy collection matrix according to the current information of the electric energy, and is also used to generate a control signal according to the current information and voltage information of the electric energy and drive the selected collection circuit through the control signal; the energy output management module is used to output and control the energy collected by the energy collection matrix. By adopting the present invention, the best conversion efficiency in a large dynamic range can be achieved, and the energy utilization can be optimized.

Description

Technical Field

[0001] The invention relates to the technical field of solar energy collection, and in particular to a solar energy maximum charging current tracking collector with a large dynamic range. Background Art

[0002] The output current and output voltage of the solar panel can change with the change of light, and the circuit parameters collected under different voltages and currents must be different.

[0003] During the power conversion process, the loss is mainly composed of four parts: the switch loss of the switch tube, the line loss composed of inductance and wires, the magnetic circuit loss, and the inherent loss of the system itself. When currents of different power sizes are converted (boosting or reducing voltage), the energy source changes dramatically, which will cause the loss of the collection circuit to change; therefore, when the current and voltage change, the switch loss, line loss and magnetic circuit loss will also change when the parameters such as the switch device and inductance remain almost unchanged.

[0004] For example, if the circuit parameters of a large current are used in a small current collection circuit, most of the electric energy will be consumed in magnetic circuit loss and switch loss, and no energy can be collected;

[0005] For example, when the circuit parameters of small current are used in a large current collection circuit, line loss, magnetic circuit saturation, etc. will cause the system to have almost no energy output.

[0006] Therefore, it is necessary to design a collection circuit with variable device parameters to ensure that the collection circuit always maintains high-efficiency power conversion. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a large dynamic range solar maximum charging current tracking collector, which can achieve the best conversion efficiency within the large dynamic range and optimize energy utilization.

[0008] In order to solve the above technical problems, the present invention provides a large dynamic range solar maximum charging current tracking collector, including an input light energy interface, an energy collection matrix, a control module and an energy output management module, the input light energy interface, the energy collection matrix and the energy output management module are connected in sequence, and the control module is connected to the input light energy interface, the energy collection matrix and the energy output management module respectively; the input light energy interface is used to access the electric energy generated by solar cells; the energy collection matrix includes at least two collection circuits with different powers, and the collection circuit is used to transfer the electric energy; the control module is used to select a collection circuit from the energy collection matrix according to the current information of the electric energy, and is also used to generate a control signal according to the current information and voltage information of the electric energy and drive the selected collection circuit through the control signal; the energy output management module is used to output and control the energy collected by the energy collection matrix.

[0009] As an improvement of the above scheme, the control module includes a main control circuit, a current detection circuit and a voltage detection circuit; the current detection circuit is connected to the main control circuit and the input light energy interface respectively, and is used to detect the current information of the electric energy in real time, and send the current information to the main control circuit; the voltage detection circuit is connected to the main control circuit and the input light energy interface respectively, and is used to detect the voltage information of the electric energy in real time, and send the voltage information to the main control circuit; the main control circuit selects a collection circuit from the energy collection matrix according to the current information, and also generates a control signal according to the current information and the voltage information and drives the selected collection circuit through the control signal.

[0010] As an improvement of the above scheme, the acquisition circuit includes an inductor, a switching tube, a diode, a voltage-stabilizing diode and a capacitor; one end of the inductor is connected to the input light energy interface, and the other end is connected to the positive electrode of the voltage-stabilizing diode, and the negative electrode of the voltage-stabilizing diode is respectively connected to the energy output management module and grounded through the capacitor; the gate of the switching tube is connected to the control module, the source is respectively connected to the positive electrode of the diode and grounded, and the drain is respectively connected to the negative electrode of the diode and the positive electrode of the voltage-stabilizing diode.

[0011] As an improvement of the above solution, in different acquisition circuits, the parameters of the inductor, switch tube, diode, voltage regulator diode and capacitor are different.

[0012] As an improvement of the above solution, the greater the current information is, the smaller the inductance in the selected acquisition circuit is.

[0013] As an improvement of the above scheme, a current interval table is preset in the control module, and the current interval table is used to record the acquisition circuit and the current interval, and the acquisition circuit and the current interval correspond one to one; when selecting the acquisition circuit from the energy acquisition matrix according to the current information of the electric energy, the current interval in which the current information is located is searched, and the acquisition circuit is determined according to the current interval.

[0014] As an improvement of the above solution, the control signal is a pulse signal, and the pulse signal includes a pulse frequency signal and a pulse width signal.

[0015] As an improvement of the above solution, the control module tracks the maximum power under the current current information through a PID algorithm to obtain an optimal charging current point, and generates a control signal according to the optimal charging current point.

[0016] The implementation of the present invention has the following beneficial effects:

[0017] The present invention optimizes multiple collection circuits of different powers to construct a special energy collection matrix, and selects a suitable collection circuit according to the size of the input current, thereby solving the problem of insufficient dynamic range of the existing light energy collection MPPT controller;

[0018] Furthermore, the present invention is combined with a reasonable current tracking algorithm to calculate the pulse width and frequency with the best efficiency, thereby achieving the best conversion efficiency in a large dynamic range and optimizing energy utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a large dynamic range solar maximum charging current tracking collector of the present invention;

[0020] Figure 2 is a circuit diagram of the main control circuit in the present invention;

[0021] Figure 3 is a circuit diagram of a current detection circuit in the present invention;

[0022] Figure 4 is a circuit diagram of a voltage detection circuit in the present invention;

[0023] Figure 5 It is a circuit diagram of the energy harvesting matrix in the present invention. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings.

[0025] See also Figure 1 , Figure 1The specific structure of the large dynamic range solar maximum charging current tracking collector of the present invention is shown, which includes an input light energy interface 1, an energy collection matrix 2, a control module 3 and an energy output management module 4. The input light energy interface 1, the energy collection matrix 2 and the energy output management module 4 are connected in sequence, and the control module 3 is connected to the input light energy interface 1, the energy collection matrix 2 and the energy output management module 4 respectively. Specifically:

[0026] The input light energy interface 1 is used to access the electric energy generated by the battery;

[0027] The energy collection matrix 2 includes at least two collection circuits 21 with different powers, and the collection circuits 21 are used to transfer and store electrical energy;

[0028] The control module 3 is used to select a collection circuit 21 from the energy collection matrix 2 according to the current information of the electric energy, and is also used to generate a control signal according to the current information and voltage information of the electric energy and drive the selected collection circuit 21 through the control signal;

[0029] The energy output management module 4 is used to control the output of the energy collected by the energy collection matrix 2 .

[0030] Different from the prior art, the present invention optimizes multiple energy collection circuits 21 with different powers to construct a special energy collection matrix 2 .

[0031] When working, the control module 3 can identify the current information and voltage information of the electric energy in real time, and then select different combinations of acquisition circuits 21 according to the current information, and generate control signals according to the current information and voltage information to drive different acquisition circuits 21, so that the efficiency of energy conversion is always maintained in the best working state, and every drop of hard-earned energy is collected and utilized as much as possible.

[0032] It should be noted that, by adjusting different acquisition circuits 21, a current interval table can be preset in the control module 3, and the current interval table is used to record the acquisition circuit 21 and the current interval, and the acquisition circuit 21 and the current interval correspond one to one; when the acquisition circuit 21 is selected from the energy acquisition matrix 2 according to the current information of the electric energy, the current interval in which the current information is located can be found by looking up the table, and the acquisition circuit 21 can be determined according to the current interval.

[0033] Therefore, the present invention can select a suitable acquisition circuit 21 according to the size of the input current, and then cooperate with a reasonable current tracking algorithm to calculate the pulse width and frequency with the best efficiency, so as to achieve the best conversion efficiency in a large dynamic range, optimize energy utilization, and ensure that every bit of energy can be reasonably preserved.

[0034] Preferably, the control signal in the present invention is a pulse signal, and the pulse signal includes a pulse frequency signal and a pulse width signal. Since the range of magnetic field intensity has a better conversion efficiency than PWM (Pulse Width Modulation), the present invention adopts a pulse adjustment method, which has better EMC and EMI performance.

[0035] Accordingly, the control module 3 tracks the maximum power under the current current information through the PID algorithm to obtain the optimal charging current point, and generates a control signal according to the optimal charging current point.

[0036] Furthermore, the control module 3 includes a main control circuit, a current detection circuit and a voltage detection circuit, wherein:

[0037] The current detection circuit is connected to the main control circuit and the input light energy interface 1 respectively, and is used to detect the current information of the electric energy in real time and send the current information to the main control circuit;

[0038] The voltage detection circuit is connected to the main control circuit and the input light energy interface 1 respectively, and is used to detect the voltage information of the electric energy in real time and send the voltage information to the main control circuit;

[0039] The main control circuit selects a collection circuit 21 from the energy collection matrix 2 according to the current information, generates a control signal according to the current information and the voltage information, and drives the selected collection circuit 21 through the control signal.

[0040] The main control circuit, current detection circuit, voltage detection circuit and energy collection matrix 2 are described below in conjunction with the specific circuit diagram:

[0041] 1. Main control circuit

[0042] like Figure 2 As shown, the main control circuit includes a main control chip U4 and peripheral circuits (such as a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8 and a third capacitor U3); the main control chip U4 is provided with a plurality of acquisition ports (HPWM1, HPWM2, HPWM3, HPWM4, HPWM5, HPWM6) corresponding one to one to the acquisition circuit 21, and the acquisition circuit 21 can be driven in a targeted manner through the acquisition ports (HPWM1, HPWM2, HPWM3, HPWM4, HPWM5, HPWM6).

[0043] 2. Current detection circuit

[0044] like Figure 3As shown, the current detection circuit includes a seventh capacitor C7, a tenth resistor R10, a seventh switch tube Q7 (a seventh diode and a seventh transistor), a seventh voltage-stabilizing diode D7 and a seventh inductor L7; wherein, the gate of the seventh transistor is connected to the port P33 of the main control circuit, the drain is connected to the port ADC_CURRENT of the main control circuit through the seventh capacitor C7 and is grounded through the seventh capacitor C7 and the tenth resistor R10, the source is grounded through the seventh inductor L7 and is connected to the port 50VOUT of the energy collection matrix 2 through the seventh voltage-stabilizing diode D7; the positive electrode of the seventh diode is connected to the source of the switch tube, and the negative electrode is connected to the drain of the switch tube.

[0045] The current information of the electric energy can be detected in real time through the current detection circuit, and the current information is sent to the main control circuit.

[0046] 3. Voltage detection circuit

[0047] like Figure 4 As shown, the voltage detection circuit includes a thirteenth resistor R13 and a fourteenth resistor R14 connected in series, one end of the thirteenth resistor R13 is connected to the solar voltage VBAT (i.e., the input light energy interface 1), and the other end is respectively connected to the fourteenth resistor R14 and the port P33 of the main control circuit.

[0048] The voltage detection circuit can detect the voltage information of the electric energy in real time and send the voltage information to the main control circuit.

[0049] 4. Energy Harvesting Matrix 2

[0050] like Figure 5 As shown, the energy collection matrix 2 includes at least two collection circuits 21 with different powers, and each collection circuit 21 includes an inductor, a switch tube, a diode, a voltage-stabilizing diode and a capacitor; wherein one end of the inductor is connected to the solar voltage VBAT (i.e., the input light energy interface 1), and the other end is connected to the positive electrode of the voltage-stabilizing diode, and the negative electrode of the voltage-stabilizing diode is respectively connected to the energy output management module 4 and grounded through the capacitor; the gate of the switch tube is connected to the control module 3, the source is respectively connected to the positive electrode of the diode and grounded, and the drain is respectively connected to the negative electrode of the diode and the positive electrode of the voltage-stabilizing diode.

[0051] In this embodiment, 6 groups of acquisition circuits are set from top to bottom, namely the first acquisition circuit, the second acquisition circuit, the third acquisition circuit, the fourth acquisition circuit, the fifth acquisition circuit, and the sixth acquisition circuit. Among them, the parameters of the inductor, the switch tube, the diode, the voltage regulator diode and the capacitor are different in different acquisition circuits. Therefore, by switching the switch tube, the matrix parameter configuration of the energy acquisition matrix 2 can be realized, and more refined hardware parameter optimization can be achieved.

[0052] It should be noted that if a large current acquisition circuit is used under low current, the main losses are in the magnetic circuit and the switch tube. At this time, it is necessary to reduce the switching frequency, increase the inductance, and appropriately increase the line resistance (because the current is small, the line loss is not so obvious). Therefore, the larger the current information, the smaller the inductance in the selected acquisition circuit 21.

[0053] In this embodiment, the value of the first inductor L1 in the first acquisition circuit is 3.3mH, the value of the second inductor L2 in the second acquisition circuit is 1mH, the value of the third inductor L3 in the third acquisition circuit is 100uH, the value of the fourth inductor L4 in the fourth acquisition circuit is 47uH, the value of the fifth inductor L5 in the fifth acquisition circuit is 10uH, and the value of the sixth inductor L6 in the sixth acquisition circuit is 3.3uH.

[0054] For example, under currents of tens of uA, the first acquisition circuit can be selected, which has large inductance and low operating frequency. At this time, the magnetic circuit loss and switching loss are effectively reduced; when the current increases to tens of ma, it can be switched to the second acquisition circuit, thereby effectively reducing the increase in magnetic circuit loss and line loss, reducing the expenditure on magnetic circuit loss and line loss, and improving the overall conversion efficiency.

[0055] Therefore, by switching different lines and cooperating multiple lines, the dynamic range of the optimal working state of the present invention can be greatly expanded, and full energy collection from day to night can be achieved.

[0056] It can be seen from the above that the present invention can adjust its own power consumption according to the input energy, and can achieve optimal collection and storage of energy in the power range of tens of uW to hundreds of kilowatts, solving the problem of insufficient dynamic range of existing light energy collection MPPT controllers.

[0057] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A large dynamic range solar maximum charging current tracking collector, characterized in that: It includes an input light energy interface, an energy collection matrix, a control module and an energy output management module, wherein the input light energy interface, the energy collection matrix and the energy output management module are connected in sequence, and the control module is connected to the input light energy interface, the energy collection matrix and the energy output management module respectively; The input light energy interface is used to access the electric energy generated by the solar cell; The energy collection matrix includes at least two collection circuits with different powers, and the collection circuit is used to transfer the electric energy; the collection circuit includes an inductor, a switch tube, a diode, a voltage-stabilizing diode and a capacitor; one end of the inductor is connected to the input light energy interface, and the other end is connected to the positive electrode of the voltage-stabilizing diode, and the negative electrode of the voltage-stabilizing diode is respectively connected to the energy output management module and grounded through the capacitor; the gate of the switch tube is connected to the control module, the source is respectively connected to the positive electrode of the diode and grounded, and the drain is respectively connected to the negative electrode of the diode and the positive electrode of the voltage-stabilizing diode; the larger the current information is, the smaller the inductance in the selected collection circuit is; The control module is used to select a collection circuit from the energy collection matrix according to the current information of the electric energy, and is also used to generate a control signal according to the current information and voltage information of the electric energy and drive the selected collection circuit through the control signal; The energy output management module is used to control the output of the energy collected by the energy collection matrix.

2. The large dynamic range solar maximum charging current tracking collector according to claim 1, characterized in that: The control module includes a main control circuit, a current detection circuit and a voltage detection circuit; The current detection circuit is connected to the main control circuit and the input light energy interface respectively, and is used to detect the current information of the electric energy in real time, and send the current information to the main control circuit; The voltage detection circuit is connected to the main control circuit and the input light energy interface respectively, and is used to detect the voltage information of the electric energy in real time, and send the voltage information to the main control circuit; The main control circuit selects a collection circuit from the energy collection matrix according to the current information, generates a control signal according to the current information and the voltage information, and drives the selected collection circuit through the control signal.

3. The large dynamic range solar maximum charging current tracking collector according to claim 1, characterized in that: In different acquisition circuits, the parameters of the inductor, switch tube, diode, voltage regulator diode and capacitor are different.

4. The large dynamic range solar maximum charging current tracking collector according to claim 1, characterized in that: The control module is preset with a current interval table, which is used to record acquisition circuits and current intervals, and the acquisition circuits and current intervals correspond one to one; When selecting a collection circuit from the energy collection matrix according to the current information of the electric energy, the current interval in which the current information is located is searched, and the collection circuit is determined according to the current interval.

5. The large dynamic range solar maximum charging current tracking collector according to claim 1, characterized in that: The control signal is a pulse signal, and the pulse signal includes a pulse frequency signal and a pulse width signal.

6. The large dynamic range solar maximum charging current tracking collector according to claim 1, characterized in that: The control module tracks the maximum power under the current current information through the PID algorithm to obtain the optimal charging current point, and generates a control signal according to the optimal charging current point.

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