CN211127272U

CN211127272U - Lead-acid battery charging management circuit of wisdom fog lamp

Info

Publication number: CN211127272U
Application number: CN201922263601.2U
Authority: CN
Inventors: 牛冬洋; 姜宽宽
Original assignee: Jiangsu Jinxiao Electronic Information Co ltd
Current assignee: Jiangsu Jinxiao Electronic Information Co ltd
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2020-07-28
Anticipated expiration: 2029-12-17

Abstract

The utility model discloses a lead acid battery charging management circuit of wisdom fog lamp belongs to photovoltaic solar charging technical field, and it includes photovoltaic solar panel, charging circuit, lead acid battery, load and monitoring circuit, photovoltaic solar panel, charging circuit, lead acid battery and load are connected according to the preface, photovoltaic solar panel, charging circuit and monitoring circuit constitute circulation circuit in proper order, monitoring circuit can automatic tracking solar panel's maximum power point, furthest's the output that utilizes solar panel, the utility model discloses, have solar panel maximum power point tracking function, wide input voltage scope, soft start function, overvoltage protection and automatic recharging can provide stable power for the load.

Description

Lead-acid battery charging management circuit of wisdom fog lamp

Technical Field

The utility model relates to a lead acid battery charging management circuit of wisdom fog lamp belongs to photovoltaic solar charging technical field.

Background

With the development of economy and social progress, people put higher and higher requirements on energy, and the search for new energy becomes an urgent subject facing human beings at present. Solar energy is a new energy source and is inexhaustible. Solar power generation is a mature technical means, and is often applied to the traffic fields such as beacon lights, traffic/railway signal lights, fog lights and the like under the outdoor condition without commercial power. However, the circuit stability of the intelligent fog lamp needs to be improved, and a lead-acid battery charging management circuit of the intelligent fog lamp is needed.

Disclosure of Invention

In order to solve the technical problem, the utility model discloses a lead acid battery charging management circuit of wisdom fog lamp, its concrete technical scheme as follows: the solar charging system comprises a photovoltaic solar panel, a charging circuit, a lead-acid battery, a load and a monitoring circuit, wherein the photovoltaic solar panel, the charging circuit, the lead-acid battery and the load are sequentially connected, and the photovoltaic solar panel, the charging circuit and the monitoring circuit sequentially form a circulation loop; the monitoring circuit automatically tracks the maximum power point of the solar panel and utilizes the output power of the solar panel to the maximum extent.

Further, the photovoltaic solar panel converts solar energy into a power supply; the charging circuit converts an unstable power supply into a charging power supply acceptable by the lead-acid battery; the lead-acid battery provides electric energy for a load circuit to use at night or under the condition that the solar panel is damaged.

Furthermore, the photovoltaic solar panel and the lead-acid battery are charged and managed, and have trickle, constant current, overcharge and floating charge modes.

Furthermore, in a charging period, when the input power supply is powered off or the input voltage is lower than the battery voltage, the monitoring circuit monitors that the low-power-consumption sleep mode is automatically started.

Further, the chip model selected by the charging circuit is as follows: CN3767, the chip is a PWM step-down 12V lead-acid battery charging management chip.

Further, the chip CN3767 comprises 10 pins,

The pin GND is connected to ground,

the MPPT pin is provided with two branches which are respectively called a branch I and a branch II, the branch is serially connected with a resistor R5, a resistor R5 is grounded, the branch is serially connected with a resistor R3, a MOS field effect transistor, a diode D1, an inductor L1, a resistor R1 and a battery anode in sequence, on the branch II,

The MOS field effect transistor is further provided with a capacitor C2 and a capacitor C1, one end of the capacitor C2 is connected with a pin VG, the other end of the capacitor C2 is connected between the MOS field effect transistor and a resistor R3, one end of the capacitor C1 is connected between the capacitor C2 and the resistor R3, and the other end of the capacitor C1 is grounded;

The pin DRV is connected with the base electrode of the MOS field effect transistor;

the inductor further comprises a diode D2, wherein one end of the diode D2 is connected between the diode D1 and the inductor L1, and the other end of the diode D2 is grounded;

pin CSP is connected between inductor L1 and resistor R1;

The pin BAT is connected with the positive electrode of the battery;

The pin COM is sequentially connected with the resistor R4 and the capacitor C4, and the capacitor C4 is grounded;

still include resistance R2, resistance R2 one end is connected with chip VCC end, and the other end is connected red L ED lamp D3's positive pole and green L ED lamp D4's positive pole respectively, and red L ED lamp D3 and green L ED lamp D4 are connected CHRG end and DONE end respectively.

Furthermore, the MPPT (maximum power point tracking) pin is a maximum power point tracking end, the voltage of the MPPT pin is limited to 1.205V, and a voltage division network is formed by matching two resistors R3 and R5 outside a chip, so that the maximum power point tracking of the solar panel is realized.

Further, the maximum power point voltage of the solar panel is determined by the following formula:

Vmppt＝1.205×(1+R3/R4)。

The utility model has the advantages that: the utility model discloses, have solar panel maximum power point tracking function, wide input voltage scope, soft start function, overvoltage protection and automatic recharging can provide stable power for the load.

Drawings

Figure 1 is a schematic diagram of the system structure of the invention,

Fig. 2 is a circuit diagram of the present invention.

Detailed Description

The present invention will be further clarified by the following description with reference to the attached drawings and specific examples, which should be understood as being merely illustrative of the present invention and not limiting the scope of the present invention, and modifications of various equivalent forms of the present invention by those skilled in the art after reading the present invention, all fall within the scope defined by the appended claims of the present application.

As shown in figure 1, its constitution of this kind of lead acid battery charging management circuit of wisdom fog lamp includes photovoltaic solar panel, charging circuit, lead acid battery, load and monitoring circuit, photovoltaic solar panel, charging circuit, lead acid battery and load are connected according to the preface, photovoltaic solar panel, charging circuit and monitoring circuit constitute circulation circuit in proper order.

The photovoltaic solar panel and the lead-acid battery are in charge management and have trickle, constant-current, overcharge and floating charge modes.

Referring to fig. 2, the BAT pin of CN3767 is connected to the positive electrode of the battery, and at the same time, the BAT pin is connected to the CSP pin to test the voltage across the current detection resistor R1, and feed back the voltage signal to the chip CN3767 for current modulation. When the VCC pin voltage is greater than the low voltage stored threshold and greater than the battery voltage, the charger operates normally to charge the battery, if the battery voltage is less than 75% of the set overcharge voltage, the charger enters a trickle charge mode where the charge current is 17.5% of the set constant current charge current, and when the battery voltage is greater than 75% of the set overcharge voltage, the charger enters a constant current charge mode where the charge current is set by an internal 0.12V reference voltage and R1, i.e., the charge current is 0.12V/R1. When the battery voltage continues to rise near the overcharge charge voltage, the charger enters an overcharge mode and the charge current gradually decreases. When the charging current is reduced to 38% of the constant current charging current, CN3767 enters a floating charging mode, the voltage of BAT pin is limited to the floating charging voltage, the transistor in the CHRG pin of the open-drain output is turned off, the output is in a high-impedance state, the transistor in the DONE pin of the other open-drain output is turned on, the low level is output, and the floating charging state is indicated.

The detection circuit automatically tracks the maximum power point of the solar panel, and a user can utilize the output power of the solar panel to the maximum extent without considering the worst condition. And in a charging period, when the input power supply is powered off or the input voltage is lower than the battery voltage, the detection circuit detects that the low-power-consumption sleep mode is automatically entered.

CN3767 adopts the constant voltage method to track the maximum power point of solar panel. In the volt-ampere characteristic curve of the solar panel, when the ambient temperature is fixed, the output voltage corresponding to the maximum output power point is basically the same under different sunshine intensities, that is, as long as the output voltage of the solar panel is kept to be a constant voltage, the maximum output power of the solar panel can be ensured when the light intensities are different under the temperature.

The voltage of the MPPT pin at the maximum power point tracking end of the CN3767 solar panel is limited to 1.205V, and the tracking of the maximum power point of the solar panel can be realized by matching with a voltage division network formed by two resistors (R3 and R5 in the figure 2) outside a chip. The maximum power point voltage of the solar panel is determined by the following formula:

Vmppt＝1.205×(1+R3/R4)

the charging circuit uses a chip model of CN3767 which is a PWM voltage-reducing 12V lead-acid battery charging management chip, and the specific connection mode is that one end of a resistor R2 is connected with a chip VCC end, the other end is respectively connected with the anode of a red L ED lamp D3 and the anode of a green L ED lamp, the L ED lamps are respectively connected with a CHRG end and a DONE end, the working state of the chip is represented by the circuit, one end of a capacitor C3 is input with the anode of the battery, the other end is connected with the ground, the filter effect is exerted on an input power supply, ripple current generated on the input power supply is absorbed, an MOS field effect transistor of a P channel is connected with a diode D1, and a DRV is connected with the base of the field effect transistor, the switching frequency of the MOS transistor is controlled, the input voltage charges an inductor, the inductor current increases, the MOS transistor turns off the inductor, the inductor discharges the battery, the inductor current decreases, the ripple current of the inductor increases along with the decrease, and increases along with the increase of the.

It is obvious to a person skilled in the art that the invention is not restricted to details of the above-described exemplary embodiments, but that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The utility model provides a lead acid battery charging management circuit of wisdom fog lamp which characterized in that: the solar energy charging system comprises a photovoltaic solar panel, a charging circuit, a lead-acid battery, a load and a monitoring circuit, wherein the photovoltaic solar panel, the charging circuit, the lead-acid battery and the load are connected in sequence, and the photovoltaic solar panel, the charging circuit and the monitoring circuit sequentially form a circulation loop.

2. The lead-acid battery charging management circuit of the smart fog lamp of claim 1, wherein: the photovoltaic solar panel converts solar energy into a power supply; the charging circuit converts an unstable power supply into a charging power supply of the lead-acid battery; the lead-acid battery provides electric energy for a load circuit to use at night or under the condition that the solar panel is damaged.

3. The lead-acid battery charging management circuit of the smart fog lamp of claim 1, wherein: and the charging modes between the photovoltaic solar panel and the lead-acid battery comprise trickle, constant current, overcharge and floating charge.

4. The lead-acid battery charging management circuit of the smart fog lamp of claim 1, wherein: the monitoring circuit can automatically track the maximum power point of the solar panel and utilize the output power of the solar panel to the maximum extent.

5. The lead-acid battery charging management circuit of the smart fog lamp of claim 1, wherein: in a charging period, when the input power supply is powered off or the input voltage is lower than the battery voltage, the monitoring circuit automatically enters a low-power-consumption sleep mode.

6. The lead-acid battery charging management circuit of the smart fog lamp of claim 1, wherein: the model of the chip selected by the charging circuit is CN3767, and the chip is a charging management chip of a PWM voltage-reducing 12V lead-acid battery.

7. The lead-acid battery charging management circuit of the smart fog lamp of claim 6, wherein: the chip CN3767 includes 10 pins,

The pin GND is connected to ground,

pin CSP is connected between inductor L1 and resistor R1;

The pin BAT is connected with the positive electrode of the battery;

8. The lead-acid battery charging management circuit of the smart fog lamp of claim 7, wherein: the MPPT of the pin is a maximum power point tracking end, the voltage of the MPPT is limited to 1.205V, and the MPPT is matched with two resistors R3 and R5 outside a chip to form a voltage division network so as to realize the maximum power point tracking of the solar panel.

9. The lead-acid battery charging management circuit of the smart fog lamp of claim 8, wherein: the maximum power point voltage of the solar panel is determined by the following formula:

Vmppt＝1.205×(1+R3/R4)。