Super capacitor protection board based on single voltage control

Abstract

The utility model relates to the technical field of super capacitor equipment protection, in particular to a super capacitor protection board based on single voltage control, which comprises a TL431 voltage stabilizing circuit, a temperature sensor and a communication module. According to the utility model, the TL431 is used as a voltage comparator of the super-capacitor monomer, and when the voltage of the super-capacitor monomer exceeds a reference value, the super-capacitor monomer is discharged, thereby achieving the purpose of controlling the voltage of the super-capacitor monomer. Meanwhile, the super capacitor protection plate is provided with a temperature sensor and a communication module, so that real-time information of the device can be transmitted to a background monitoring center, and a user can conveniently monitor in real time. The design overcomes the defects of a traditional passive equalization circuit, such as low voltage equalizing precision and high energy consumption, and efficient, accurate and energy-saving super capacitor protection and management are realized through an innovative circuit structure and an intelligent management strategy.

Description

Technical Field

[0001] The utility model relates to the technical field of supercapacitor device protection, in particular to a supercapacitor protection board based on single-cell voltage control. Background Technique

[0002] A supercapacitor is a new type of energy storage electrical component, which has a higher energy density than traditional capacitors; a higher power density, longer life, and faster charge and discharge time than lithium batteries; at the same time, it has characteristics such as ultra-low temperature performance, high reliability, and environmental friendliness, making it widely used as a power or energy storage power source in many fields.

[0003] In the application of supercapacitors, since each capacitor cell may have different performances due to manufacturing differences, aging, or other factors, this may lead to voltage imbalance between the cells during the charging or discharging process. Voltage imbalance may cause some capacitor cells to be overcharged or over-discharged, thus affecting the performance and life of the entire capacitor bank.

[0004] In the existing protection boards for supercapacitor modules, a passive equalization circuit is generally adopted, in which a resistor is directly connected in parallel with the supercapacitor. A resistor is connected in parallel to each cell to suppress the leaked charge. In fact, resistors with very small tolerances are used to force the voltages of individual modules to be the same.

[0005] During the charging process of a supercapacitor, the internal resistance determines the magnitude of the charging current and the final voltage. After the supercapacitor is charged, the self-discharge internal resistance is another important parameter. The voltage balance between supercapacitor cells can be achieved with a small resistor. The resistance value of the resistor should be much larger than the internal resistance of the supercapacitor but smaller than the self-discharge resistance. Different resistance values result in different voltage balance process times. It can be seen that although the passive equalization circuit can achieve voltage balance to a certain extent, it has problems of low equalization accuracy and high energy consumption. Content of the Utility Model

[0006] The purpose of the utility model is to provide a supercapacitor protection board based on single-cell voltage control to solve the problems of low equalization accuracy and high energy consumption of the passive equalization circuit in the above background technique.

[0007] The utility model provides the following technical solution: A supercapacitor protection board based on single-cell voltage control includes a supercapacitor module and a TL431 voltage stabilization circuit. The supercapacitor module includes several supercapacitor cells connected in series, and a TL431 voltage stabilization circuit is connected to the input end of each supercapacitor cell.

[0008] The TL431 voltage stabilization circuit includes a voltage comparator, a triode Q48, and a first resistor network, where:

[0009] The voltage comparator is connected to a first resistor network;

[0010] The output terminal of the voltage comparator is connected to the base of transistor Q48;

[0011] The transistor Q48 further includes a collector and an emitter for grounding.

[0012] As a further improvement of this technical solution, the voltage comparator includes a TL431 chip U48 and resistors R504, R503, and R516, where:

[0013] The reference electrode of the TL431 chip U48 is connected to resistor R504 and resistor R503, the cathode of the TL431 chip U48 is connected to resistor R516 and resistor R528, and the other end of the resistor R528 is connected to the transistor Q48.

[0014] As a further improvement of this technical solution, the first resistor network is four parallel voltage-dividing resistors, namely resistor R189, R190, R191, and R192, and the resistor R189, R190, R191, and R192 are connected in parallel outside the resistor R503 and resistor R504.

[0015] As a further improvement of this technical solution, a second resistor network is connected outside the TL431 chip U48, a temperature sensor is connected outside the second resistor network, and the second resistor network is a parallel connection of resistor R552, R540, and sub-R564.

[0016] As a further improvement of this technical solution, the emitter of the transistor Q48 is connected to the positive electrode of the supercapacitor cell C1, the collector of the transistor Q48 is connected to the second resistor network and the positive electrode of the diode D48, and the base of the transistor Q48 is connected to the current-limiting resistor R528;

[0017] The negative electrode of the diode D48 is connected to the resistor R576.

[0018] Preferably, the diode D48 is a light-emitting diode.

[0019] Compared with the prior art, the beneficial effects of the present utility model are:

[0020] 1. Using TL431 as the voltage comparator of the supercapacitor cell, when the voltage of the supercapacitor cell exceeds the reference value, the supercapacitor cell is discharged, so as to achieve the purpose of controlling the voltage of the supercapacitor cell. Compared with the current balancing circuit used, the TL431 voltage stabilizing circuit has high precision and strong current discharge ability, and can meet the protection requirements of large-capacity supercapacitor modules.

[0021] 2. The integrated design simplifies the system complexity, reduces the manufacturing cost, and the enhanced protection measures and intelligent control strategies ensure the stable operation and long-term life of the capacitor bank.

[0022] 3. The real-time monitoring and remote communication capabilities improve the system controllability and response speed. Brief Description of the Drawings

[0023] Figure 1 It is a schematic diagram of the overall structure of the present utility model;

[0024] Figure 2 It is a schematic diagram of the TL431 voltage regulator circuit. Detailed Embodiment

[0025] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0026] To describe in detail the technical content, structural features, achieved objectives and effects of the present invention, the following combines the embodiments

[0027] and is described in detail in conjunction with the drawings.

[0028] Please refer to Figure 1-2 , an embodiment provided by the present utility model:

[0029] A supercapacitor protection board based on single-cell voltage control includes a supercapacitor module and a TL431 voltage regulator circuit. The supercapacitor module includes a plurality of supercapacitor cells connected in series, and a TL431 voltage regulator circuit is connected to the input end of each supercapacitor cell;

[0030] The TL431 voltage regulator circuit includes a voltage comparator, a triode Q48, and a first resistor network, where:

[0031] The voltage comparator is connected to the first resistor network;

[0032] The output end of the voltage comparator is connected to the base of the triode Q48;

[0033] The triode Q48 also includes a collector and an emitter for grounding.

[0034] The charging current of the supercapacitor is recommended to be a constant current. A DC-DC converter (such as TPS5430) controlled by PWM is used as the charging controller. The PWM duty cycle is adjusted by the microcontroller to set the target charging current to 2A. The microcontroller dynamically adjusts the duty cycle according to the charging state and temperature feedback of the supercapacitor to ensure a constant current.

[0035] The TL431 chip U48 of model TL431CSF is used in combination with a 10KΩ resistor R504, an 11.3KΩ resistor R503, and a 1KΩ resistor R516 to form a voltage comparator. Specifically, the reference electrode of the TL431 chip U48 is connected to the bias resistors R504 and R503. The cathode of the TL431 chip U48 is connected to the current-limiting resistors R516 and R528. The other end of the current-limiting resistor R528 is connected to the triode Q48, and the reference voltage is set to 2.5V. The safety threshold is adjusted through the first resistor network. The first resistor network includes resistors R189, R190, R191, and R192 with a resistance value of 300Ω each. The resistors R189, R190, R191, and R192 are connected in parallel outside the resistors R503 and R504. When the voltage of the supercapacitor C1 (parameters: 350F / 2.7V) exceeds the preset safety threshold, the output of the TL431 chip U48 will become a low-resistance state, and the output voltage will approach its positive supply voltage. This high-level signal will be transmitted to the base of the triode Q48 of model SS8550, causing the triode Q48 to conduct. When the triode Q48 conducts, the resistance between its collector and emitter is greatly reduced, forming a low-impedance discharge path. This discharge path starts from the positive pole of the supercapacitor C1, passes through the resistor R528 to the base of the triode Q48, and then grounds through the collector and emitter of the triode Q48. In this way, the energy in the supercapacitor will be quickly released through this discharge path to prevent damage or safety hazards caused by excessive capacitor voltage.

[0036] In addition, there is also a second resistor network connected to the TL431 chip U48. The second resistor network includes the resistors R552, R540, and R564 connected in parallel. The second resistor network cooperates with the temperature sensor, as well as the resistors R576 and the diode D48 (LED_green) to monitor the temperature.

[0037] Among them, the temperature sensor uses a high-precision NTC thermistor installed near the supercapacitor bank. After being divided by a precision resistor, it is connected to the ADC input of the microcontroller. The temperature threshold is set to 60°C. Once the temperature exceeds the threshold, the microcontroller will initiate cooling measures or disconnect the charging circuit.

[0038] The communication module selects the Wi-Fi module ESP8266 as the communication core, supports the TCP / IP protocol stack, and communicates with the microcontroller through the SPI interface. The data format is JSON, which contains real-time information such as voltage and temperature, establishes a connection with the background server, and realizes remote monitoring and control.

[0039] Working principle:

[0040] A number of TL431 voltage regulator circuits are respectively connected to a number of supercapacitor monomers in the supercapacitor module one by one. A precision voltage comparator with the TL431 chip U48 of the model TL431CSF as the core, in cooperation with the triode Q48 of the model SS8550, constructs an active equalization system. All the parameters of the supercapacitor monomers are 350F / 2.7V. When the TL431CSF chip U48 detects that the voltage of the supercapacitor monomer C1 exceeds the preset safety threshold, the voltage of its cathode rises and outputs a high-level signal. This signal is connected to the base of the triode Q48, making a low voltage formed between the base and the emitter of the triode Q48, resulting in the conduction of the triode Q48. When the triode Q48 conducts, the resistance from the collector to the emitter decreases significantly, which is equivalent to creating a low-impedance path from the supercapacitor to the ground. In this way, when the voltage of the supercapacitor monomer C1 exceeds the safe range, the overvoltage capacitor is discharged through a specific resistor, and the excess charge is released from this path, preventing the capacitor from overvoltage, ensuring that the voltage of the capacitor monomer is maintained within the safe range, effectively preventing the overvoltage phenomenon, and playing a protective role.

[0041] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present utility model. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, it is intended to encompass all changes falling within the meaning and scope of the equivalent elements of the claims in the present utility model. Any reference signs in the claims should not be regarded as limiting the claimed rights.

Claims

1. A supercapacitor protection board based on single cell voltage control, characterized in that: It includes a supercapacitor module and a TL431 voltage stabilizing circuit, wherein the supercapacitor module includes a plurality of supercapacitor cells connected in series, and the input end of each supercapacitor cell is connected to a TL431 voltage stabilizing circuit; The TL431 voltage stabilizing circuit includes a voltage comparator, a transistor Q48 and a first resistor network, wherein: The voltage comparator is connected to the first resistor network; The output end of the voltage comparator is connected to the base of transistor Q48; The transistor Q48 further includes a collector and an emitter for grounding.

2. The supercapacitor protection board based on single cell voltage control according to claim 1, characterized in that: The voltage comparator includes a TL431 chip U48 and resistors R504, R503 and R516, wherein: The reference pole of the TL431 chip U48 is connected to the resistor R504 and the resistor R503, the cathode of the TL431 chip U48 is connected to the resistor R516 and the resistor R528, and the other end of the resistor R528 is connected to the transistor Q48.

3. The supercapacitor protection board based on single cell voltage control according to claim 2, characterized in that: The first resistor network is four voltage-dividing resistors connected in parallel, namely resistors R189, R190, R191 and R192. The resistors R189, R190, R191 and R192 are connected in parallel outside the resistors R503 and R504.

4. The supercapacitor protection board based on single cell voltage control according to claim 3, characterized in that: The TL431 chip U48 is externally connected to a second resistor network, the second resistor network is externally connected to a temperature sensor, and the second resistor network is resistors R552, R540 and R564 connected in parallel.

5. The supercapacitor protection board based on single cell voltage control according to claim 4, characterized in that: The emitter of the transistor Q48 is connected to the positive electrode of the super capacitor cell C1, the collector of the transistor Q48 is connected to the second resistor network and the positive electrode of the diode D48, and the base of the transistor Q48 is connected to the current limiting resistor R528; The cathode of the diode D48 is connected to the resistor R576.

6. The supercapacitor protection board based on single cell voltage control according to claim 5, characterized in that: The diode D48 is a light emitting diode.

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