CN108233520A - A kind of photovoltaic generation electric storage device - Google Patents

Abstract

The invention discloses a photovoltaic power storage device. The photovoltaic power storage device includes a solar cell assembly, a single battery, a Buck circuit, a Boost circuit, a battery protection circuit, a detection circuit for detecting whether there is sunlight, and a controller. , a signal conditioning circuit and a display component, the output end of the solar cell assembly is connected to the input end of the Buck circuit, the output end of the Buck circuit is connected to the single battery through the battery protection circuit on the one hand, and in addition On the one hand, the Boost circuit is connected to the display component, and the signal conditioning circuit is electrically connected to the Buck circuit, Boost circuit, battery protection circuit, controller, and detection circuit. Adopting the photovoltaic power generation and storage device of the present invention can improve the cycle life of the battery, and also enable the device to use a standard 18V solar cell module. In addition, the constant current drive of the integrated Boost circuit can reduce the configuration of the drive circuit of the display component. Thereby reducing the cost of the photovoltaic power storage device.

Description

A photovoltaic power generation and storage device

technical field

The invention relates to the field of photovoltaic power generation and storage, in particular to a single battery photovoltaic power storage device.

Background technique

Solar power is a kind of clean energy, but photovoltaic power generation has a time limit, and battery energy storage needs to be added to facilitate use at different times. Small solar energy storage systems are currently mostly used for energy supply in street lamps and areas without electricity, to solve the problem of power generation and storage in application scenarios without mains electricity. In the early days, there were many energy storage methods using lead-acid batteries in the market, but lead-acid batteries were gradually replaced by lithium batteries due to their shortcomings of not being environmentally friendly, short life, and high maintenance costs.

A common solution in the market for small photovoltaic lithium battery integrated power generation and storage devices is to use 18V photovoltaic panels, connect 4 strings of lithium batteries for energy storage through photovoltaic controllers and battery management systems, and then output constant voltage 12V constant voltage power supplies to to the LED head. Due to the use of multiple single cells in series, because the temperature is not consistent, the equalization effect is not good, resulting in faster capacity decay after the batteries are grouped, and the battery life is much lower than that of the single cells. Moreover, after multiple strings, the voltage is high. In the case of customer backup power requirements, only small-capacity single batteries can be selected, and the battery cost is relatively high.

Contents of the invention

Based on this, in order to solve the above-mentioned technical problems in the traditional technology, a photovoltaic power storage device is proposed.

A photovoltaic power storage device, which includes a solar cell assembly, a single cell, a charge and discharge control circuit, and a detection circuit for detecting whether there is sunlight, and the solar cell assembly, the single cell, and the detection circuit are all compatible with the The charging and discharging control circuit is electrically connected.

Further, the charging and discharging control circuit includes a Buck circuit and a Boost circuit, the input end of the Buck circuit is connected to the solar battery module, and the Boost circuit is electrically connected between the output end of the Buck circuit and the load;

Further, the charging and discharging control circuit further includes a battery protection circuit, and the battery protection circuit is electrically connected between the output terminal of the Buck circuit and the single battery.

Further, the charge and discharge control circuit also includes a controller and a signal conditioning circuit, the signal conditioning circuit is electrically connected to the controller, Buck circuit, Boost circuit, battery protection circuit and detection circuit, and the signal conditioning circuit is used for It is used to collect, convert and transmit signals between the controller and the Buck circuit, Boost circuit, battery protection circuit and detection circuit.

Further, the Buck circuit includes a first switch circuit, a second switch circuit, a first inductor, a first diode, and a first capacitor, the first switch circuit is connected in series with the second switch circuit, and the first switch circuit is connected in series with the second switch circuit. An inductor is connected in series with the first capacitor to form a parallel branch with the first diode, and the parallel branch is connected in series with the second switch circuit.

Further, the battery protection circuit includes a third switch circuit, a fourth switch circuit, and an overcurrent protection device, and the overcurrent protection device, the third switch circuit, and the fourth switch circuit are sequentially connected in series to the positive pole of the single battery and Between the output terminals of the Buck circuit.

Further, the Boost circuit includes a second inductor, a fifth switch circuit, a sixth switch circuit, a second capacitor and a first resistor, and the sixth switch circuit is connected in parallel with the fifth switch circuit after being connected in series with the second capacitor A parallel branch is formed, and the parallel branch is connected in series between the second inductor and the first resistor.

Further, the charging and discharging control circuit further includes a communication circuit, and the controller sends monitoring information to other terminal devices through the communication circuit.

Further, the single battery is a large-capacity single battery or a supercapacitor.

Further, the load is an LED lamp.

Using the photovoltaic power generation and storage device of the present invention, a large-capacity single battery is used to increase the life of the battery, and a standard 18V solar battery module can be directly used, and the driving circuit of the LED lamp can be reduced by integrating the constant current drive design of the Boost circuit, Therefore, the design cost of the solar photovoltaic power storage device is reduced.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

in:

Figure 1 is a structural block diagram of a photovoltaic power storage device with a single battery;

Fig. 2 is a structural block diagram of the charge and discharge control circuit;

Fig. 3 is the structural block diagram of Buck circuit;

Fig. 4 is a structural block diagram of the battery protection circuit;

Fig. 5 is the structural block diagram of Boost circuit;

Fig. 6 is the structural block diagram of the alternative mode of MOS switch circuit of the present invention;

Fig. 7 is the circuit diagram of Buck circuit, Boost circuit, battery protection circuit of the present invention

Among them, (1)-solar battery module, (2)-charge and discharge control circuit, (3)-single battery, (4)-display component, (5)-detection circuit, (6)-signal conditioning circuit, ( 7)-Buck circuit, (8)-controller, (9)-battery protection circuit, (10)-Boost circuit, (11)-communication circuit, P+-positive terminal output of solar cell module, P--solar cell The negative terminal output of the component, the positive terminal output of Vbus+-Buck circuit, the negative terminal output of Vbus--Buck circuit, the positive terminal output of Vled+-Boost circuit, the negative terminal output of Vled--Boost circuit, S1-the first switch circuit , S2-second switch circuit, L1-first inductor, C1-first capacitor, D1-first diode, S3-third switch circuit, S4-fourth switch circuit, F1-overcurrent protection device, L2 - the second inductor, S5 - the fifth switch circuit, S6 - the sixth switch circuit, C2 - the second capacitor, R1 - the first resistor, S7 - the mechanical electronic switch, D2 - the second diode.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

FIG. 1 is a structural block diagram of the photovoltaic power generation and storage device of the present invention. The photovoltaic power storage device of the present invention comprises a solar battery module (1), a charging and discharging control circuit (2), a single battery (3), a detection circuit (5) for detecting whether there is sunlight, and a display part (4) , the solar battery module (1) is connected to the input end of the charge and discharge control circuit (2), the output end of the charge and discharge control circuit (2) is connected to the display part (4), and the monomer Both the battery (3) and the detection circuit (5) are electrically connected to the charge and discharge control circuit (2).

When the sun shines during the day, the solar cell assembly (1) converts solar energy into battery electric energy, and the charge and discharge control circuit (2) controls the solar cell assembly (1) to generate electricity for the battery according to the detection information of the detection circuit (5). The single battery (3) is charged, and the discharge circuit of the charge and discharge control circuit (2) does not work, so that the display unit (4) does not work; when there is no sunlight at night, the charge and discharge control circuit (2) Control the single battery (3) to supply power to the display part (4) according to the detection information of the detection circuit (5), and the display part (4) works.

Specifically, the single battery (3) can be a large-capacity single lithium battery, or a supercapacitor.

Specifically, the detection circuit (5) may be a circuit composed of a light-controlled switch and a photosensitive sensor, and the light-controlled switch transfers the light signal into an electrical signal through the photosensitive sensor and sends it to the charge and discharge control circuit (2); It is a circuit that detects the input voltage of the solar cell module and judges it. More specifically, a threshold can be set. If there is sunlight during the day, the output voltage of the solar cell module (1) is greater than the threshold, and there is no sunlight at night. The output voltage of the component (1) is lower than the threshold value, so the on and off of the display part (4) can be controlled through the relationship between the output voltage of the solar cell component (1) and the threshold value.

Specifically, the display component (4) may be a common lighting fixture such as an LED lamp or a fluorescent lamp.

In the present invention, by using the single battery (3), the cycle life of the battery can reach the limit, thereby reducing the cost of the photovoltaic power storage device.

Figure 2 is a structural block diagram of the charge and discharge control circuit, as shown in the figure, the charge and discharge control circuit (2) includes a Buck circuit (7), a Boost circuit (10), a battery protection circuit (9), a signal conditioning circuit ( 6), controller (8) and communication circuit (11), the input end of described Buck circuit (7) is connected with described solar cell module (1), the output end of described Buck circuit (7) passes through described on the one hand The battery protection circuit (9) is connected to the single battery (3), on the other hand, it is connected to the display component (4) through the Boost circuit (10), and the signal conditioning circuit (6) is connected to the The Buck circuit (7), Boost circuit (10), battery protection circuit (9), controller (8), detection circuit (5), and communication circuit (11) are electrically connected.

The signal conditioning circuit (6) is used to control the communication between the controller (8) and the Buck circuit (7), the Boost circuit (10), the battery protection circuit (9), the detection circuit (5), and the communication circuit (11). The signal is collected, converted and transmitted, and the signal conditioning circuit (6) includes an AD converter, an interface circuit, a driving circuit and the like.

The output of the solar cell assembly (1) is P+, P-, the output of the Buck circuit (7) is Vbus+, Vbus-, the output of the Boost circuit (10) is Vled+, Vled-, the monomer The output of the battery (3) is Vbat+, Vbat-.

When there is light during the day, the solar cell module (1) converts light energy into electrical energy, and is connected to the Buck circuit (7) in the charging and discharging control circuit (2) through P+/P-, and the Buck circuit (7) collects the solar cell module ( The input voltage of 1) is controlled by the input constant voltage, and the Buck circuit (7) outputs Vbus+/Vbus- voltage clamped by the single battery (3), and adapts the power change of the solar cell module through the change of the current. The output voltage Vbus+/Vbus- of the Buck circuit (7) is connected to the single battery (3) through the battery protection circuit (9) to realize charging of the single battery (3); when the battery is fully charged, the controller (8 ) to send a corresponding command to close the Buck circuit (7) through the signal conditioning circuit (6) to stop charging. The light control switch transfers the light signal into an electrical signal through the photosensitive sensor, and then connects to the signal conditioning circuit (6). After the signal is conditioned, it is connected to the controller (8), and the controller (8) closes the Boost circuit according to the light control signal ( 10), the display unit (4) does not work.

When there is no light at night, the controller (8) receives an effective light control conditioning signal from the light control switch, and sends an instruction to start the Boost circuit (10), the single battery (3) supplies power to the Boost circuit (10), and the Boost circuit (10) The circuit (10) outputs a 12V power supply to drive the display unit (4) to work.

In addition, the charge and discharge control circuit (2) also sends monitoring information to the monitoring equipment through the communication circuit (11) for debugging and on-site maintenance. Specifically, the monitoring information includes information such as whether the single battery (3) is damaged or needs to be replaced, and the monitoring device may specifically be various terminals such as computers and mobile phones, or may be an LCD display screen.

As shown in Figure 3, it is the structural block diagram of Buck circuit (7) of the present invention, as can be seen from the figure, described Buck circuit (7) comprises first switch circuit S1, second switch circuit S2, first inductance L1, The first capacitor C1 and the first diode D1, the source of the first switch circuit S1 is connected to the positive terminal output P+ of the solar battery module (1), and the drain of the first switch circuit S1 is connected to the positive terminal output P+ of the first switch circuit S1. The drain of the second switch circuit S2 is connected, the source of the second switch circuit S2 is connected to one end of the first inductor L1 on the one hand, and connected to the cathode of the first diode D1 on the other hand, the first The other end of the sensor L1 is connected to one end of the first capacitor C1, and the anode of the first diode D1 and the other end of the first capacitor are both connected to the negative terminal output P- of the solar cell module (1) and connected to the circuit For reference, the gates of the first switch circuit S1 and the second switch circuit S2 are both electrically coupled to the output end of the signal conditioning circuit (6). The Buck circuit (7) works in a pulse width modulation mode, when the first switch circuit S1 and the second switch circuit S2 are in a conducting state, the solar cell assembly (1) charges the first inductor L1; when the When the first switch circuit S1 and the second switch circuit S2 are in the cut-off state, the first inductor L1, the first capacitor C1 and the first diode D1 form a path, the first inductor L1 discharges, and the first capacitor C1 charges. The controller (8) controls the on-off time of the first switch circuit S1 and the second switch circuit S2, thereby adjusting the change of the current to adapt to the change of the output power of the solar battery module (1). When the output power increases, the controller (8) controls the conduction time of the first switch circuit S1 and the second switch circuit S2 to increase, so that the current increases and the power increases; otherwise, when the solar energy When the output power of the battery assembly (1) decreases, the controller (8) controls the conduction time of the first switch circuit S1 and the second switch circuit S2 to be shortened, so that the current decreases and the power decreases . By controlling the turn-on and turn-off times of the first switch circuit S1 and the second switch circuit S2 of the Buck circuit (7), thereby increasing or decreasing the current of the Buck circuit (7) to adapt the solar battery module ( 1) changes in the output power, so that the solar battery module (1) can adopt a standard 18V solar battery module, which reduces the difficulty of industrial matching and the cost of the solar battery module (1).

As shown in Figure 4, it is a structural block diagram of the battery protection circuit (9) of the present invention, as can be seen from the figure, the battery protection circuit (9) includes the third switch circuit S3, the fourth switch circuit S4 and overcurrent protection Device F1, the source of the third switch circuit S3 is connected to the positive output Vbus+ of the Buck circuit (7), and the drain of the third switch circuit S3 is connected to the drain of the fourth switch circuit S4 , the source of the fourth switch circuit S4 is connected to one end of the overcurrent protection device F1, the other end of the overcurrent protection device F1 is connected to the positive pole of the single battery (3), and the single battery The negative pole of the battery (3) is connected to the negative terminal output Vbus- of the Buck circuit (7), and is connected to the circuit reference ground. The gates of the third switch circuit S3 and the fourth switch circuit S4 are both electrically connected to the output end of the signal conditioning circuit (6). The controller (8) controls the on and off states of the third switch circuit S3 and the fourth switch circuit S4 through the signal conditioning circuit (6) so as to realize the control of the single battery (3) on the display unit (4) power supply and protection to the single battery (3). When there is no sunlight at night, the single battery (3) supplies power to the display unit (4), and the controller (8) controls the third switch circuit S3 and the fourth switch circuit S4 to be turned on state, the single battery (3) supplies power to the Boost circuit (10), thereby driving the LED light to turn on. When the signal conditioning circuit (6) detects that the single battery (3) is in the condition of overvoltage, undervoltage, high temperature, low temperature, overcurrent or short circuit, the controller (8) sends a corresponding instruction through signal conditioning The circuit (6) disconnects the third switch circuit S3 and the fourth switch circuit S4 of the battery protection circuit (9), thereby disconnecting the power supply circuit of the single battery (3) and protecting the single battery (3) .

Specifically, the third switch circuit S3 may be a P-channel MOS transistor, or an N-channel MOS transistor.

Specifically, the overcurrent protection device F1 may be a fuse.

Fig. 5 is the structural block diagram of Boost circuit (10) of the present invention, as shown in the figure, described Boost circuit (10) comprises second inductance L2, the 5th switching circuit S5, the 6th switching circuit S6, the 2nd capacitance C2 and The first resistor R1, one end of the second inductance L2 is connected to one end of the battery protection circuit (9), and the other end of the second inductance L2 is connected to the source of the sixth switch circuit S6 on the one hand, On the other hand, it is connected to the drain of the fifth switch circuit S5, the source of the fifth switch circuit S5 is connected to one end of the first resistor R1, and the drain of the sixth switch circuit S6 is connected to the second One end of the capacitor C2 is connected, the other end of the second capacitor C2 is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the negative terminal of the single battery (3) and connected to the circuit reference ground.

Specifically, the resistance of the first resistor R1 is generally small, on the order of milliohms, usually 10-20 milliohms. The first resistor R1 may also be other current detection devices, specifically, it may be a Hall sensor, a current transformer, and the like.

The Boost circuit (10) of the present invention has two control modes, one is to collect output voltage and current, control constant voltage and limited power output, and provide 12V constant voltage to the display component control board. The other is to collect the output voltage and current, control the constant current, limit the power output, and save the driver of the display part.

Fig. 6 is the structural block diagram of another alternative mode of the switch MOS tube circuit of the present invention, as can be seen from Fig. 6, the switch circuit of battery protection circuit (9) can be the switch MOS tube in Fig. 4, also can It is a switching circuit composed of a mechanical electronic switch S7 connected in parallel with a second diode D2.

Fig. 7 is the circuit diagram of Buck circuit, Boost circuit, battery protection circuit of the present invention, as shown in the figure, when sunlight is irradiated in daytime, the output terminal P+ and P- of described solar cell assembly are input to Buck circuit (7) input terminal, the detection circuit (5) detects whether there is sunlight and sends the detection information to the controller (8), and the controller (8) controls the first switch through the signal conditioning circuit (6) The circuit S1 and the second switch circuit S2 work in a pulse width modulation mode, the third switch circuit S3 and the fourth switch circuit S4 are in a conduction state, and the Buck circuit (7) collects the voltage input to the solar battery module (1) to perform Input constant voltage control, the Buck circuit (7) outputs Vbus+/Vbus- voltage clamped by the single battery (3), and the controller (8) controls the first switch S1 tube and the second switch S2 tube The on-off time of the current is used to control the change of the current, so as to adapt to the power change of the solar cell module, and the output of the Buck circuit (7) is connected to the single battery (3) through the battery protection circuit (9), thereby realizing The solar battery charges the single battery (3); when the single battery (3) is fully charged, the controller (8) sends an instruction to close the Buck circuit (7) through the signal conditioning circuit (6) to stop charging. The controller (8) also controls whether the Boost works through the signal conditioning circuit according to the detection information of the detection circuit (5), thereby controlling the LED light to be turned on and off. When there is no sunlight at night, the detection circuit (5) sends the detection information to the controller (8) by detecting sunlight or detecting the output voltage of the solar cell assembly, and the controller (8) sends a command , the third switch circuit S3 and the fourth switch circuit S4 are controlled by the signal conditioning circuit (6) to be in a conducting state, the fifth switch circuit S5 and the sixth switch circuit S6 work in an interleaved and complementary pulse width modulation mode, and the The Boost circuit (10) collects the output voltage and current of the single battery (3), and the controller (8) controls the Boost circuit (10) to realize constant voltage or constant current limited power output, thereby realizing the A bulk battery (3) supplies power to the display unit (4).

The photovoltaic power generation and storage device of the present invention has the following advantages:

1. Use large-capacity single batteries to improve battery cycle life and save costs;

2. The use of Buck circuit can use standard 18V solar cell components, reducing the difficulty of industrial matching and the cost of solar cell components;

3. The integrated Boost constant current driver can reduce the repeated configuration of the driver in the display unit and reduce the cost.

The above disclosures are only preferred embodiments of the present invention, and certainly cannot limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention still fall within the scope of the present invention.

Claims (10)

1. a kind of photovoltaic generation electric storage device, including solar cell module, single battery, charge-discharge control circuit and For detecting whether there is the detection circuit of sunlight, the solar cell module, single battery and detection circuit are and institute State charge-discharge control circuit electrical connection.

2. a kind of photovoltaic generation electric storage device as described in claim 1, it is characterised in that：The charge-discharge control circuit includes Buck circuits, Boost circuit, the input terminal of the Buck circuits are connect with the solar cell module, the Boost circuit It is electrically connected between output terminal and the load of the Buck circuits.

3. a kind of photovoltaic generation electric storage device as claimed in claim 2, it is characterised in that：The charge-discharge control circuit also wraps Include battery protecting circuit, the battery protecting circuit be electrically connected to the Buck circuits output terminal and the single battery it Between.

4. a kind of photovoltaic generation electric storage device as claimed in claim 3, it is characterised in that：The charge-discharge control circuit also wraps Controller, signal conditioning circuit are included, the signal conditioning circuit is protected with the controller, Buck circuits, Boost circuit, battery Protection circuit and detection circuit electrical connection, the signal conditioning circuit are used for the controller and the Buck circuits, Boost Signal between circuit, battery protecting circuit, detection circuit is acquired, converts and transmits.

5. a kind of photovoltaic generation electric storage device as claimed in claim 3, it is characterised in that：The Buck circuits are opened including first Powered-down road, second switch circuit, the first inductance, the first diode, the first capacitance, the first switch circuit are opened with described second Parallel branch is formed with first diodes in parallel after powered-down road series connection, first inductance and first capacitance series connection, The parallel branch is connected in series with the second switch circuit.

6. a kind of photovoltaic generation electric storage device as claimed in claim 4, it is characterised in that：The battery protecting circuit includes the Three switching circuits, the 4th switching circuit and over-current protection device, the over-current protection device, the 4th switching circuit, third are opened Powered-down road is sequentially connected in series between the anode of single battery and the output terminal of Buck circuits.

7. a kind of photovoltaic generation electric storage device as claimed in claim 4, it is characterised in that：The Boost circuit includes second Inductance, the 5th switching circuit, the 6th switching circuit, the second capacitance and first resistor, the 6th switching circuit and the second electricity In parallel with the 5th switching circuit after appearance series connection to form parallel branch, the parallel branch is serially connected in the second inductance and the first electricity Between resistance.

8. a kind of photovoltaic generation electric storage device as claimed in claim 6, it is characterised in that：The charge-discharge control circuit also wraps Telecommunication circuit is included, the controller sends monitoring information by the telecommunication circuit to other-end equipment.

9. a kind of photovoltaic generation electric storage device as described in claim 1, it is characterised in that：The single battery is large capacity single Body battery or super capacitor.

10. a kind of photovoltaic generation electric storage device as claimed in claim 2, it is characterised in that：The load is LED light.