Disclosure of utility model
The utility model aims to provide a solar charging controller with a common-ground Bluetooth function, which is used for solving the technical problems existing in the prior art.
In order to achieve the above purpose, the solar charging controller with the common-ground Bluetooth function comprises a solar battery, a storage battery, a load LED, a central control MCU Bluetooth communication module, a PWM charging module, a power management module, a flat voltage current limiting module, a voltage sampling module and a backflow prevention circuit, wherein the backflow prevention circuit is connected with the PWM driving circuit, the negative electrode of the solar battery and the negative electrode of the storage battery are grounded to a common ground GND, the flat voltage current limiting circuit comprises a power MOSFET circuit and a current sampling circuit, and the voltage sampling circuit comprises a solar battery voltage sampling circuit and a storage battery voltage sampling circuit;
The solar charging controller with the common-ground Bluetooth function is used for controlling a solar panel, a storage battery and a load, the storage battery is charged in a three-section PWM charging mode when the voltage exists on the solar panel in daytime, the load is closed at the moment, the load is opened at night when the voltage does not exist on the solar panel, the voltage of the storage battery reaches the working voltage of the load through a flat-voltage module and is subjected to current limiting output, and meanwhile, time period control is carried out to meet various time period requirements of a user.
Further, the solar charging controller with the common-ground Bluetooth function can directly drive the LED street lamp, and read-write and OTA upgrading are carried out on parameters in the controller through the smart phone APP.
Furthermore, the MCU Bluetooth communication module takes a single chip microcomputer PHY6212 chip as a main chip, is provided with a 6-bit AD channel, has an integrated Bluetooth communication function, realizes system voltage sampling, is imported into a control algorithm to calculate, then outputs a control signal to the whole solar charge-discharge controller system, has an internal integrated Bluetooth function, adopts a Bluetooth Mesh low-power technology, and performs parameter issuing and real-time parameter reading on the controller through a mobile phone APP to realize OTA upgrading.
Further, the negative electrode of the solar battery in the PWM charging module and the negative electrode of the storage battery are connected with the common ground GND, and the PWM charging module comprises an anti-backflow circuit and a PWM driving circuit, and is used for controlling the solar battery panel to charge the storage battery according to a preset charging curve, so that damage to the storage battery caused by over-discharge, over-charge and over-pressure is avoided, PWM charging is carried out through the driving circuit of the MOS tube and the single chip microcomputer instruction control of the MOS tube, and the storage battery is protected from over-discharge, over-charge and over-pressure through the sampling circuit.
Further, the battery management module provides MCU power supply, PWM driving voltage and indication lamp circuit power supply to monitor and protect the battery.
Further, the flat voltage current limiting circuit in the flat voltage current limiting module comprises a power MOSFET circuit and a current sampling circuit, the flat voltage current limiting circuit is connected with the anode of the solar battery, the battery voltage is outputted in a flat voltage mode to the load through the flat voltage circuit, the battery voltage of the single string of lithium iron phosphate battery cells is 3.2V, the output current range is 0-10A, and the power cannot exceed 30W.
Further, the voltage sampling module collects the voltage of the solar panel and the voltage of the battery through resistor voltage division, the negative electrode of the solar battery and the negative electrode of the storage battery are grounded to the common ground GND, and the voltage of the solar battery is collected through resistor voltage division.
The utility model has the following advantages:
1. the system has the self-checking function of the primary power-on system, and can automatically detect the accuracy of the wiring sequence;
2. the method is applicable to occasions where the load working voltage is equal to the storage battery voltage;
3. the charging mode adopts the common ground GND of the negative electrode of the solar cell and the negative electrode of the storage battery, so that the service life of the solar cell panel is prolonged, the conversion efficiency of the controller is improved, and the voltage sampling of the solar cell is more convenient.
The IP67 waterproof grade, excellent heat balance design and natural air cooling can be used in various severe environments;
5. The intelligent control mode is suitable for the lithium battery, and can automatically adjust the charge and discharge strategy according to the condition of the storage battery;
6. perfect electronic protection function, load overcurrent, short-circuit protection, battery overcharge protection, battery low-voltage protection and the like;
7. And a BLE 5.0Mesh technology is adopted, so that the real-time parameters of the controller are checked through the mobile phone APP with low cost, low power consumption and high reliability, and the parameters of the controller are modified.
And 8, the OTA upgrading function can carry out OTA upgrading on the controller firmware, and the product can be continuously maintained by manufacturers after being sold, so that the controller function is ensured to be advanced at the moment, and the time and the cost after being sold are greatly reduced.
9. The solar energy storage battery charging and discharging management system is applied to a single-string (3.2V) system, integrates the solar energy storage battery charging and discharging management, and is small in size, attractive in appearance, high in reliability, low in failure rate and low in cost.
The foregoing description is only an overview of the present utility model, and is intended to be implemented in accordance with the teachings of the present utility model, as well as the preferred embodiments thereof, together with the following detailed description of the utility model, given by way of illustration only, together with the accompanying drawings.
Detailed Description
The technical solution of the present utility model will be clearly and completely described in conjunction with the specific embodiments, but it should be understood by those skilled in the art that the embodiments described below are only for illustrating the present utility model and should not be construed as limiting the scope of the present utility model. All other embodiments, which can be made by one of ordinary skill in the art without undue burden on the person of ordinary skill in the art based on the embodiments of the present utility model, are within the scope of the present utility model.
The common-ground Bluetooth solar street lamp charging controller integrates MCU and Bluetooth communication functions by adopting the PHY6212, thereby meeting the cost requirement. The communication distance also meets the requirements and is not affected by sunlight. The prior hand-held remote controller is removed, so that the cost is saved for manufacturers and clients, and the operation of the intelligent mobile phone with one hand is changed into that of a person, and the operation is more convenient, simple and flexible. And moreover, OTA upgrading can be realized by utilizing the Bluetooth communication chip, so that the maintenance cost is reduced.
The utility model provides a charging circuit of a solar charging controller with a common ground structure, aiming at the defects of the prior art, and the charging circuit has high conversion efficiency. The battery is excessively discharged for a long time for some reasons, so that the voltage is excessively low and is not enough to provide MCU power supply, the common-ground charging mode can provide MCU power supply and timely collect battery voltage when the solar panel has voltage in the daytime, in order to protect the battery controller, the battery controller starts to charge with a small current from design, and when the battery voltage rises and charges with a large current, the service life of the solar panel and the reliability of the controller are improved, so that the solar battery voltage is convenient to sample, simple in structure and convenient to realize. The discharge adopts a single power MOSFET constant current mode, the discharge current sampling removes the traditional operational amplification mode of adopting reference voltage resistance voltage division, and the central processing unit adopts PHY6212 to integrate MCU and Bluetooth communication functions, thereby greatly reducing the cost.
The utility model aims to realize a charging circuit of a solar charging controller with a common ground structure through the following technical measures, and reduce the cost of the controller through simplifying the charging and discharging circuits. The intelligent power supply comprises a solar battery, a storage battery, a load LED, a central processing unit Bluetooth communication circuit, a PWM charging circuit, a flat voltage current limiting circuit, a voltage sampling circuit and a power supply management circuit. The solar battery is characterized by further comprising a backflow prevention circuit, wherein the backflow prevention circuit is connected with the PWM driving circuit, and the negative electrode of the solar battery and the negative electrode of the storage battery are grounded to the common ground GND. The flat voltage current limiting circuit comprises a power MOSFET circuit and a current sampling circuit, and the voltage sampling circuit comprises a solar battery voltage sampling circuit and a storage battery voltage sampling circuit. The anti-backflow circuit is used for loading the LED to start illumination at night, and the anti-backflow circuit prevents the voltage of the storage battery from flowing backwards to the solar battery end, so that the controller misjudges that the solar battery end has electricity in daytime, and the controller is considered to close the LED to drive the non-lighting lamp in the charging state.
The common-ground Bluetooth solar street lamp charging controller is specially designed for a solar storage battery, and aims at the defects of the prior art, the common-ground structure solar charging controller is high in conversion efficiency, the storage battery is excessively low in voltage due to long-term overdischarge for some reasons, and the common-ground charging mode can provide MCU power supply and timely collect battery voltage when a solar cell panel has voltage in the daytime, so that the battery controller is protected to be charged with a small current from the beginning of design, and then is charged with a large current when the battery voltage rises, so that the service life of the solar cell panel and the reliability of the controller are improved, and the solar cell voltage is convenient to sample, simple in structure and convenient to realize. The controller can directly drive the LED street lamp, has small volume, is easy to install and extremely convenient to use, and can read, write and OTA upgrade parameters in the controller through the intelligent mobile phone APP. The controller adopts intelligent digital chip set communication to integrally carry out flat voltage current limiting control of the load end, accuracy and reliability are improved, and the current sampling adopts a reference voltage resistor voltage dividing mode, so that material and maintenance cost is reduced. And the multi-period and LED dimming control is supported, so that the load control is more flexible. Meanwhile, the battery has unique short circuit and reverse connection prevention protection, full-charge, over-discharge automatic turn-off, recovery and other full-function protection measures, and detailed charging, storage battery state, load and various fault indications. The parameters such as the voltage of the storage battery, the voltage of the photocell, the discharge current and the like are sampled through the chip, the high-accuracy control of the discharge rate correction conforming to the characteristics of the storage battery is realized through the calculation of a special control model, the storage battery is charged by adopting an intelligent and efficient PWM charging mode, and the efficiency of the solar cell panel is fully utilized.
As shown in FIG. 1, the common-ground Bluetooth solar street lamp charging controller comprises an MCU control Bluetooth communication module, a PWM charging module, a power management module, a flat voltage current limiting module and a voltage sampling module. It is a controller for controlling solar panel, accumulator and load. And in the daytime, when the solar panel has voltage, the storage battery is charged by adopting a three-section PWM charging mode, and at the moment, the load is closed. At night, when the solar panel has no voltage, the load is opened, and the voltage of the storage battery reaches the working voltage of the load through the flat-voltage module and is subjected to current limiting output. Meanwhile, the time period control is carried out to match with various time period demands of users.
The functions of each module are as follows:
1. the central control Bluetooth communication module is mainly characterized in that an MCU control circuit takes a single chip microcomputer PHY6212 chip as a main chip, and the main chip is provided with a 6-bit AD channel and integrates a Bluetooth communication function. And realizing system voltage sampling, importing the system voltage sampling into a control algorithm for calculation, and then outputting a control signal to the whole solar charge-discharge controller system. The Bluetooth function is integrated internally, the Bluetooth Mesh low-power consumption technology is adopted, parameters are issued and real-time parameters are read through the mobile phone APP to the controller, and OTA upgrading is achieved.
And the PWM charging module is characterized in that the negative electrode of the solar battery and the negative electrode of the storage battery are connected with the common ground GND, and the PWM charging module comprises a backflow prevention circuit and a PWM driving circuit. And controlling the solar panel to charge the storage battery according to a set charging curve. The damage of the storage battery caused by over-discharge, over-charge and over-pressure is avoided. The working principle is that the MOS is controlled by a driving circuit of the MOS tube and a singlechip instruction to carry out PWM charging, and the storage battery is over-discharged, over-charged and over-voltage protected by a sampling circuit.
3. And the battery management module is used for providing MCU power supply, PWM driving voltage and power supply of the indicator light circuit to monitor and protect the battery.
4. And the flat voltage current limiting circuit comprises a power MOSFET circuit and a current sampling circuit, and the flat voltage circuit is connected with the anode of the solar battery. The battery voltage (such as about 3.2V of single-string lithium iron phosphate battery core) is subjected to flat voltage output (the number of the string of the load lamp panels is 1 string of 30 parallel lamp panels, the output voltage is equal to the input voltage) to the load through a flat voltage circuit, and the output current ranges from 0 to 10A (determined by the self setting of a customer) but the power cannot exceed 30W.
5. And the voltage sampling module is used for collecting the voltage of the solar panel and the voltage of the battery through resistor voltage division. The negative electrode of the solar battery and the negative electrode of the storage battery are grounded to the common ground GND, and the voltage of the solar battery can be acquired through resistor voltage division.
Specifically, the overall circuit structure of the hardware:
1) The central control Bluetooth communication module is shown in fig. 2, wherein a main chip MCU (U1) integrates a Bluetooth communication part, a single chip PHY6212 chip is used as a main chip, and the main chip is provided with a 6-bit AD channel, so that system voltage sampling is realized, and the system voltage is led into a control algorithm for calculation and charge and discharge control. And a BLE 5.0Mesh technology is adopted, so that the real-time parameters of the controller are checked through the mobile phone APP with low cost, low power consumption and high reliability, and the parameters of the controller are modified. The controller firmware can be upgraded in an OTA mode, the product can be maintained continuously by a manufacturer after being sold, the function of the controller is guaranteed to be advanced in time, and the time and the cost after being sold are greatly reduced. VCC is subjected to LC filtering through FB1 and C12 to supply power to the chip, C21, R24 and C20 form a pi-type matching circuit, and U4 is a Bluetooth radio frequency antenna.
2) The PWM charging module is characterized in that a charging control circuit is shown in fig. 3, the photocell ground and the storage battery ground are commonly grounded, the photocell voltage rises in the daytime, when the singlechip detects that the storage battery voltage is lower than a set value, charging is started, specifically, when one end (PWQG _PV) of R14 is connected with a U1 pin of the singlechip and output is at a high level, Q2 is conducted and grounded, Q3, Q6, Q1 and Q7 are PMOS tubes, at the moment, the driving pins are at a low level and are conducted, and when the singlechip output is at a low level, the PMOS tubes are at a cut-off state and do not charge the storage battery. The Q1 and Q7 are anti-backflow effects, when the photocell is in no voltage at night, the voltage of the storage battery cannot be reversely poured to the photocell end under the action of the Q1 and Q7, and the original diode is changed into the PMOS tube, so that the charging efficiency is higher.
3) The flat voltage current limiting module is shown in fig. 4, and is suitable for the situation that the battery voltage is single-string 3.2V, and the load LED voltage is equal to the battery voltage. The storage battery starts to discharge the load LED at night, the output current is limited through the power MOS tube Q11, and the on-off of the Q11 is controlled by the singlechip. R16 and R25 are output current sampling resistors, the collected voltage is changed into ILOAD voltage through RC filtering and is connected to an AD pin of the singlechip, and an output current value is determined by an internal collection algorithm of the singlechip. 1.2V is the voltage output by the MCU from the band as the reference voltage of sampling, the sampling voltage enters the linear region of the single chip microcomputer AD through the partial pressure of R5 and R26, the resolution of the AD is improved, and finally the accuracy of the output current is increased. And collecting the discharge current to judge whether the protection is open-circuit protection or short-circuit protection. And meanwhile, the mobile phone APP sends out an electric current parameter to adjust the load current. The current magnitude can be set according to various discharge mode time periods, and intelligent operation is realized.
4) The battery management module is shown in fig. 5, and the prior scheme is not shared with the battery ground, so that the battery can only be powered from the battery end for cost requirement, and the condition that the battery is out of power possibly causes the circuit to be complex. The common scheme is that the storage battery and the photocell are respectively connected with the input of U2 through diodes D1 and D2, the controller is in a powered state no matter in daytime or at night, U2 is a low-dropout LDO, the output VCC supplies power to the singlechip, the MOS drive and the indicating lamp, the power supply circuit is simple, and the standby power consumption is low. The common scheme is applied to a single-string (3.2V) system, integrates charge and discharge management of a solar storage battery, and has the advantages of small volume, attractive appearance, high reliability, low failure rate and low cost.
5) The voltage sampling module is shown in fig. 6, because the photocell ground and the storage battery ground are commonly grounded, compared with the prior scheme, the photocell voltage acquisition is easier, and the circuit is simple. The voltage division VPV of the resistors R311 and R312 is connected with the AD pin of the singlechip, so that the voltage acquisition of the photocell is realized. VBAT is battery voltage acquisition. And judging whether to discharge or charge by collecting the voltage of the storage battery and the voltage of the photocell.
The utility model adopts IP67 waterproof grade, excellent heat balance design and natural air cooling, and can be used in various severe environments.
While the utility model has been described in detail in the foregoing general description and specific examples, it will be apparent to those skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the utility model and are intended to be within the scope of the utility model as claimed.