CN206820541U - A solar uninterruptible power supply management system - Google Patents

Abstract

The utility model relates to a solar energy uninterrupted power source management system, include main control unit, solar photovoltaic cell, overflow overvoltage protection circuit, prevent flowing backward control circuit, input undervoltage judgement circuit, maximum power point tracking and battery charge-discharge management, lithium cell group, battery voltage acquisition and balanced charging circuit and multiplexed output control circuit. The utility model has the advantages that: the utility model bypasses the step of direct current to alternating current, directly increases and decreases the voltage of the input power supply to charge the battery through the maximum power point tracking algorithm, and simultaneously, the power supply voltage-decreasing chip is internally used for outputting stable power supply to supply power to external equipment; utilize the lithium cell as energy storage, the utility model discloses from taking battery protection circuit, integrated data memory, having the input and preventing flowing backward the circuit, effectively utilizing solar photovoltaic cell electric energy, band communication function and multichannel communication interface, have the trouble and report to the police in advance, can provide the operating condition who supports entire system in real time, support the controllable output of multichannel power and multichannel power input.

Description

A solar uninterruptible power supply management system

technical field

The invention relates to the technical field of energy utilization, in particular to a solar uninterruptible power supply management system.

Background technique

In the existing solar uninterruptible power supply management system, it is basically boosted by low-voltage DC and then inverted into high-voltage AC, but the equipment needs to convert the high-voltage AC power into a DC low-voltage power supply suitable for the needs of its own system, which greatly reduces The efficiency of solar energy use. In addition, the existing solar uninterruptible power supply management system has high cost and is difficult to control the power output. Basically, the use of batteries results in large volume and high weight, and is not suitable for low-voltage power supply small and medium-power electrical appliances.

Contents of the invention

In order to overcome the above problems, the present invention provides a solar energy uninterruptible power supply management system, which bypasses the step of converting DC to AC, and directly uses the input power to charge the battery through the maximum power point tracking algorithm. Internally use a power step-down chip to output a stable power supply to supply power to external devices; the present invention uses a lithium battery as energy storage, and the present invention has small size, low cost, built-in battery protection circuit, integrated data memory, input anti-backflow circuit, effective Utilizes the electric energy of solar photovoltaic cells, has communication function and multi-channel communication interface, has fault pre-alarm, can provide the working status of the whole system in real time, supports multi-channel power supply controllable output and multi-channel power input; the invention has high integration and application Flexible and versatile.

In order to achieve the above object, the present invention provides the following technical solutions:

A solar uninterruptible power supply management system, including a main controller, a solar photovoltaic cell, an overcurrent and overvoltage protection circuit, an anti-backflow control circuit, an input undervoltage judgment circuit, maximum power point tracking and battery charge and discharge management, a lithium battery pack, Battery voltage acquisition and balance charging circuit and multiple output control circuit;

The solar photovoltaic cell, the overcurrent and overvoltage protection circuit, the anti-backflow control circuit, the maximum power point tracking and battery charge and discharge management are electrically connected to the main controller in sequence;

The input undervoltage judgment circuit, the lithium battery pack and the multi-output control circuit are all electrically connected to the maximum power point tracking and battery charge and discharge management;

The battery voltage acquisition and balance charging circuit, the input undervoltage judgment circuit and the multiple output control circuit are all electrically connected to the main controller.

Further, the anti-backflow control circuit includes a MOS transistor Q1, a transistor U1, a resistor R4, a resistor R5, a resistor R6, and a resistor R7, wherein the Q1 drain of the MOS transistor is connected to pin 1 of the transistor U1, and the Q1 gate of the MOS transistor is connected to The pin 3 of the transistor U1 is connected, the Q1 source of the MOS tube is connected with the pin 3 of the transistor U1 and the pin of the resistor R7, the pin 6 of the transistor U1 is connected with one end of R4, one end of R5 and one end of R6, and the pin 2 of the transistor U1 is connected with One end of R5 is connected, pin 5 of transistor U1 is connected with one end of R6, and one end of R4 is connected with one end of R7 to the GND of the power supply.

Further, the maximum power point tracking and battery charge and discharge management include a controllable step-down circuit, a battery discharge control circuit and battery MPPT charging; the controllable step-down circuit includes a MOS transistor Q2, an inductor L1, a diode D2, a diode D3, Capacitor CT2, transistor Q6, transistor Q8, resistor R3, resistor R1, resistor R8 and resistor R11; the battery discharge control circuit includes MOS transistor Q4, MOS transistor Q5, transistor U3, transistor Q9, resistor R2, resistor R9, resistor R12 , resistor R18, resistor R19, resistor R20 and resistor R21.

Further, the multi-output control circuit includes a plurality of controllable power supply output circuits, and the controllable power supply output circuit includes a MOS transistor Q11, a resistor R31, a resistor R32, a resistor R35 and a transistor Q13.

Further, the input undervoltage judging circuit includes a comparator U7, a resistor R43, a resistor R33, a resistor R44, a resistor R34 and a resistor R38.

Further, the battery voltage acquisition and balance charging circuit includes a battery voltage acquisition circuit and a battery balance charging circuit; the battery voltage acquisition circuit includes an operational amplifier U8, a resistor R40, a resistor R41, a resistor R46, a resistor R47 and a resistor R39; the The battery balancing charging circuit includes a MOS transistor Q12, a transistor Q15, a resistor R42, a resistor R37, a resistor R49 and a resistor R48.

Further, it also includes a temperature collection module, the temperature collection module is electrically connected to the main controller, and is used for collecting temperature information.

Further, the temperature acquisition module includes a thermistor R80, a resistor R81 and a resistor R79.

Further, it also includes a memory, a remote transmission module, a man-machine exchange module and a communication interface module, and the memory, the remote transmission module, the man-machine exchange module and the communication interface module are all electrically connected to the main controller .

The beneficial effects that the present invention has include:

Use a main control system to track the maximum power point of one or more solar photovoltaic cell inputs, so as to maximize the use of the electric energy generated by the solar photovoltaic cell to charge the lithium battery. The invention preferentially uses solar photovoltaic cells to supply power to loads and fully utilizes solar energy. When the power supply of solar photovoltaic cells is insufficient and the voltage drops to 14V, the system will quickly switch to battery power to achieve uninterrupted power supply. Each input port of the system has overvoltage protection, and the MOSFET is used for anti-backflow design, which is more efficient than the conventional diode anti-backflow design, and more effectively utilizes the energy of the input power supply. The main control system samples the battery voltage and battery charging current of each group at the same time, and performs overcharge and overdischarge protection for each battery. When the battery group is charging, it also performs balanced charging on the battery to make the voltage of each lithium battery in series To achieve a relative balance between each other, the life of the lithium battery is increased, and the power consumption time of the battery can be increased during use. The main control system monitors the current of each external output port in real time, effectively preventing the damage to the system when the external equipment is damaged, and improving the stability of the system. The solar uninterruptible power supply management system can also transmit real-time data through GPRS, GSM, 3G or 4G, which can realize other systems to remotely read the status of the system and control the output of the system. When there is a fault and the system has power input, the system will send the fault information to the administrator, so that the administrator can know what the fault is, so as to effectively deal with the fault. The system also has other communication interfaces, which is more convenient for the access of other systems. The system has an internal clock and data memory, which can store data sent from the outside, and can start and execute certain control instructions at regular intervals.

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.

Fig. 1 is a functional block diagram of the solar uninterruptible power supply management system of the present invention.

Fig. 2 is a partial circuit schematic diagram of the solar uninterruptible power supply management system of the present invention.

Fig. 3 is a principle diagram of battery voltage detection and battery balance charging of the solar uninterruptible power supply management system of the present invention.

Fig. 4 is a schematic diagram of a power supply input voltage undervoltage judging circuit of the solar uninterruptible power supply management system of the present invention.

Fig. 5 is a schematic diagram of the controllable power supply output circuit of the solar uninterruptible power supply management system of the present invention.

Fig. 6 is a principle diagram of the internal temperature collection of the solar uninterruptible power supply management system of the present invention.

Fig. 7 is a schematic diagram of the memory of the solar uninterruptible power supply management system of the present invention.

The reference signs are explained as follows:

1. Solar photovoltaic cells; 2. Overcurrent and overvoltage protection circuit; 3. Anti-backflow control circuit; 4. Maximum power point tracking and battery charge and discharge management; 5. Lithium battery pack; 6. Battery voltage acquisition and balance charging circuit; 7. Memory; 8. Temperature acquisition module; 9. Remote transmission module; 10. Man-machine exchange module; 11. Communication interface module; 12. Main controller; 13. Multiple output control circuit; 14. Input undervoltage judgment circuit ; 15. Maximum power point tracking and battery charge and discharge management.

detailed description

In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Apparently, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other implementations obtained by persons of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

As shown in Figure 1, a solar uninterruptible power supply management system provided by the present invention includes a main controller 12, a solar photovoltaic cell 1, an overcurrent and overvoltage protection circuit 2, an anti-backflow control circuit 3, and an input undervoltage judgment circuit 14 , maximum power point tracking and battery charging and discharging management 4, lithium battery pack 5, battery voltage acquisition and balanced charging circuit 6 and multiple output control circuit 13;

The solar photovoltaic cell 1, the overcurrent and overvoltage protection circuit 2, the anti-backflow control circuit 3, the maximum power point tracking and battery charge and discharge management 4 are electrically connected to the main controller 12 in sequence;

The input undervoltage judgment circuit 14, the lithium battery pack 5 and the multi-output control circuit 13 are all electrically connected to the maximum power point tracking and battery charge and discharge management 4;

The battery voltage acquisition and balance charging circuit 6 , the input undervoltage judgment circuit 14 and the multiple output control circuit 13 are all electrically connected to the main controller 12 .

Among them, Figure 2 is the input overcurrent and overvoltage protection, anti-reverse connection and anti-backflow, battery MPPT charging and discharging circuit. As shown in the figure, each input port of the system is connected with a fuse to protect the system from overcurrent, and a transient voltage suppression diode is connected after the fuse for overvoltage protection circuit design, providing a power supply suitable for the working voltage and overvoltage protection circuit for the entire system. It can effectively protect the system when the system is struck by lightning. The anti-backflow control circuit 3 includes a MOS transistor Q1, a transistor U1, a resistor R4, a resistor R5, a resistor R6, and a resistor R7, wherein the Q1 drain of the MOS transistor is connected to pin 1 of the transistor U1, and the Q1 gate of the MOS transistor is connected to the transistor U1. Pin 3 of U1 is connected, the source of Q1 of the MOS tube is connected to pin 3 of transistor U1 and one pin of resistor R7, pin 6 of transistor U1 is connected to one end of R4, one end of R5 and one end of R6, and pin 2 of transistor U1 is connected to R5 One end of the transistor U1 is connected to one end of R6, one end of R4 is connected to one end of R7 to the GND of the power supply, and this circuit is improved into a simple comparator by applying the principle of mirror current source. When Q1’s drain voltage is lower than the source voltage, the MOS tube is turned on, and when the drain voltage of Q1 is lower than the source voltage, the MOS tube stops conducting, which can prevent the current from being poured into the solar photovoltaic cell 1 and damage the solar photovoltaic cell 1. This method is different from the traditional diode Compared with anti-backflow, the voltage drop is only one-tenth of the traditional diode. For example, the voltage drop of the new high-current low-drop Schottky is about 0.3V, and the voltage drop of the MOS tube used in this invention is used for anti-backflow. It is 0.03V, when the current is 5A, the loss is about 5(A)*0.3(V)=1.5W when Schottky is used as the anti-backflow design, and the loss of using MOS tube is 5(A)*0.03(V )=0.15W, so the MOS tube used in this invention is used to prevent backflow, greatly reducing loss and improving overall efficiency.

The controllable step-down circuit includes MOS tube Q2, inductor L1, diode D2, diode D3, capacitor CT2, transistor Q6, transistor Q8, resistor R3, resistor R1, resistor R8, and resistor R11. No more details; the PWM output pin of the main controller 12 controls the switch of the transistor Q8 and then controls the switch of the transistor Q6 and finally controls the switch of Q2 to realize the control of the controllable step-down circuit. The main controller 12 controls the battery voltage And the reading of the charging current, and adjust the duty cycle of the PWM wave to modulate the charging current, realize the maximum power point tracking and realize the efficient charging of the battery, so the maximum use of the electric energy generated by the solar photovoltaic cell 1 is used to charge the lithium battery ; When the system is just powered on, the main controller 12 will immediately judge the battery voltage, and when it is judged that the battery is not fully charged and can be charged, the controllable step-down circuit will quickly control the output voltage at a voltage of more than three volts higher than the battery voltage to the battery. Charging, and then use the disturbance tracking algorithm to change the charging current by slightly changing the duty cycle of the PWM, and change the duty cycle of the PWM multiple times in real time to obtain the maximum charging current point, so as to achieve the maximum power point and make full use of solar energy.

The battery discharge control circuit includes MOS transistor Q4, MOS transistor Q5, transistor U3, transistor Q9, resistor R2, resistor R9, resistor R12, resistor R18, resistor R19, resistor R20, resistor R21, and the connections of the components are shown in the figure. No more details; the main controller 12 controls the switch of the transistor O9 through the resistor R12 to control the switch of Q4, and finally controls the discharge of the battery. The main controller 12 performs reasonable discharge management by collecting the battery voltage in real time. When the battery voltage is less than 2.8V, the system will stop discharging the lithium battery, thus effectively protecting the battery from overcharging and overdischarging, so that the lithium battery has a longer service life; MOS tube Q5, transistor U3, resistor R18, resistor R19, resistor The ideal diode anti-backflow circuit composed of R20 and resistor R21 is used to prevent uncontrollable damage caused by backflow of VCC current to the battery. The DC-DC circuit in Figure 2 is a relatively mature voltage stabilizing circuit, so I won't repeat it here.

Figure 3 is a schematic diagram of battery voltage detection and battery balance charging. Its single-cell lithium battery voltage acquisition circuit includes operational amplifier U8, resistor R40, resistor R41, resistor R46, resistor R47, and resistor R39. The connections of each device are shown in the figure. No more details are given here, the subtracter circuit formed by it enables the main controller 12 to accurately read the voltage at both ends of the lithium battery; its single-cell lithium battery balance charging circuit includes a MOS transistor Q12, a transistor Q15, a resistor R42, a resistor R37, and a resistor R49 and resistor R48 are connected as shown in the figure, and will not be repeated here. The main controller 12 reads the voltage of each battery in real time when the lithium battery pack 5 is charging. When it is higher than 1% of other batteries, the system starts the balance charging mode, and the battery with too high voltage is bypassed through the MOS tube, and the battery with a lower battery will continue to charge. When the voltage error of all batteries is less than 0.6%, the balance charging mode Stop, this is an active balance charge, compared to the traditional method of full charging and then bypassing, this circuit balances the voltage of each battery in the battery pack in real time, the traditional single-cell lithium battery is fully charged and then balanced will still cause the battery to be slightly overcharged, so this Real-time balanced charging makes the lithium battery have a longer service life.

Figure 4 is a schematic diagram of the power supply input voltage undervoltage judgment circuit, which includes a comparator U7, a resistor R43, a resistor R33, a resistor R44, a resistor R34, and a resistor R38. When the power input voltage is less than 14V, the circuit will quickly send an undervoltage signal to the main controller 12. The main controller 12 reads the signal through the external interrupt pin of the chip and starts the battery discharge after reading it quickly to ensure the stable output of the system power supply. .

Figure 5 is a schematic diagram of a controllable power supply output circuit. One of the controllable power supply output circuits includes a MOS transistor Q11, a resistor R31, a resistor R32, a resistor R35, and a transistor Q13. The connections of each device are shown in the figure, and will not be repeated here. Through this circuit, the main controller 12 can control the switch of the MOS transistor Q11 through the switch of the resistor R35 according to the system requirements, and then control the power output; its output current monitoring circuit includes a current detection chip U6, a resistor R30, and a resistor R36, and its components are connected to As shown in the figure, and will not be described here, when the main controller 12 reads that the output current exceeds the set value, the main controller 12 will cut off the power output to ensure the stability of the system.

FIG. 6 is a schematic diagram of the internal temperature acquisition module 8 . It includes a thermistor R80, a resistor R81, and a resistor R79. The connection of each device is as shown in the figure, and will not be repeated here. The main controller 12 can read the internal temperature of the power management system through this circuit. When the internal temperature of the management system exceeds the set temperature value, it will send a fault to the server and enter the sleep mode to protect the entire power management system from being damaged due to working in an excessively high temperature environment.

Figure 7 is a schematic diagram of the memory 7, which includes a memory 7U12, a resistor R82, and a resistor R78. The connections of the devices are shown in the figure, and will not be repeated here. The main controller 12 can send commands from the outside through the SCL pin and The SDA pin is stored in the memory 7. For example, when an instruction sent by an external device requires that the power output of channel A be turned on at nine o'clock every day, the main control will set the timing through the internal timer of the main control. A power output.

Secondly, the main controller 12 carries out remote data real-time transmission through the serial port and remote transmission modules 9 such as GPRS, GSM, 3G or 4G, so that other systems can remotely read the state of this system and control the output of this system. When a more serious failure occurs such as battery damage (except for the remote transmission module 9) and the system has power input, the system will actively send the failure information to the administrator, so that the administrator knows what the failure is, so as to effectively deal with the failure; the main controller 12 Regularly send heartbeats to the server through the remote transmission module 9. When the server has not received the heartbeat of the device for many times and has not received the information that the device sends a low battery voltage before this, the server will think that the communication module of the device is damaged, and send this information to the server. To the administrator, notify the administrator to carry out maintenance processing, so that the maintenance of the entire system equipment is more convenient. The main controller 12 can be connected to other equipment systems through the communication interface, so that other equipment systems can flexibly use the solar uninterruptible power supply management system. When the equipment is just installed and maintained, the main controller 12 can also display basic information such as the voltage of each battery in the system, the voltage of the solar panel, the actual charging current, the full state of the battery, the current ambient temperature, the discharge current, and whether the battery is damaged through the human-computer interaction module. Status, which is convenient for debugging and maintenance personnel to understand the basic status of the equipment, and facilitates the debugging and maintenance of the solar uninterruptible power supply management system.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (9)

1. A solar uninterruptible power supply management system, characterized in that: comprising a main controller, a solar photovoltaic cell, an overcurrent and overvoltage protection circuit, an anti-backflow control circuit, an input undervoltage judgment circuit, maximum power point tracking and battery charging and discharging Management, lithium battery pack, battery voltage acquisition and balance charging circuit and multi-output control circuit; The solar photovoltaic cell, the overcurrent and overvoltage protection circuit, the anti-backflow control circuit, the maximum power point tracking and battery charge and discharge management are electrically connected to the main controller in sequence; The input undervoltage judgment circuit, the lithium battery pack and the multi-output control circuit are all electrically connected to the maximum power point tracking and battery charge and discharge management; The battery voltage acquisition and balance charging circuit, the input undervoltage judgment circuit and the multiple output control circuit are all electrically connected to the main controller. 2. The solar energy uninterruptible power supply management system according to claim 1, wherein the anti-backflow control circuit includes a MOS tube Q1, a transistor U1, a resistor R4, a resistor R5, a resistor R6, and a resistor R7, wherein the MOS tube The drain of Q1 is connected to pin 1 of transistor U1, the gate of Q1 of MOS transistor is connected to pin 3 of transistor U1, the source of Q1 of MOS transistor is connected to pin 3 of transistor U1 and one end pin of resistor R7, and pin 6 of transistor U1 is connected to pin 3 of transistor U1. One end of R4, one end of R5 are connected to one end of R6, the second pin of transistor U1 is connected to one end of R5, the fifth pin of transistor U1 is connected to one end of R6, one end of R4 is connected to one end of R7 to the GND of the power supply. 3. The solar uninterruptible power supply management system according to claim 1, wherein the maximum power point tracking and battery charging and discharging management include a controllable step-down circuit, a battery discharge control circuit and battery MPPT charging; The voltage control circuit includes MOS tube Q2, inductor L1, diode D2, diode D3, capacitor CT2, transistor Q6, transistor Q8, resistor R3, resistor R1, resistor R8 and resistor R11; the battery discharge control circuit includes MOS tube Q4, MOS tube Q5, transistor U3, transistor Q9, resistor R2, resistor R9, resistor R12, resistor R18, resistor R19, resistor R20 and resistor R21. 4. The solar uninterruptible power supply management system according to claim 1, wherein the multi-channel output control circuit includes a plurality of controllable power supply output circuits, and the controllable power supply output circuit includes a MOS transistor Q11, a resistor R31 , resistor R32, resistor R35 and transistor Q13. 5. The solar uninterruptible power supply management system according to claim 1, wherein the input undervoltage judgment circuit comprises a comparator U7, a resistor R43, a resistor R33, a resistor R44, a resistor R34 and a resistor R38. 6. The solar uninterruptible power supply management system according to claim 1, wherein the battery voltage acquisition and balanced charging circuit comprises a battery voltage acquisition circuit and a battery balanced charging circuit; the battery voltage acquisition circuit comprises an operational amplifier U8 , resistor R40, resistor R41, resistor R46, resistor R47 and resistor R39; the battery balancing charging circuit includes a MOS tube Q12, a transistor Q15, a resistor R42, a resistor R37, a resistor R49 and a resistor R48. 7 . The solar uninterruptible power supply management system according to claim 1 , further comprising a temperature acquisition module electrically connected to the main controller for collecting temperature information. 8 . 8 . The solar uninterruptible power supply management system according to claim 7 , further comprising that the temperature acquisition module includes a thermistor R80 , a resistor R81 and a resistor R79 . 9. The solar uninterruptible power supply management system according to claim 1, further comprising a memory, a remote transmission module, a man-machine exchange module and a communication interface module, the memory, the remote transmission module, the human Both the machine switch module and the communication interface module are electrically connected to the main controller.