Voltage detection circuit and voltage detection system for fuel cell

Abstract

The invention provides a voltage detection circuit and a voltage detection system of a fuel cell, the fuel cell comprises at least two battery packs, each battery pack comprises at least one single cell, the voltage detection circuit comprises a controller and at least two voltage monitoring modules, and the voltage monitoring modules are in one-to-one correspondence with the battery packs. Different input ends of the voltage monitoring module are used for being connected with the two ends of the corresponding battery pack respectively, the output end of the voltage monitoring module is connected with the input end of the controller, and the voltage monitoring module is used for monitoring voltage data of the corresponding battery pack and transmitting the voltage data to the controller. The output end of each voltage monitoring module is connected with the input end of the controller through the independent connecting line, so that even if one voltage monitoring module in the voltage detection circuit breaks down, other voltage monitoring modules can still continue to monitor the corresponding battery pack, interruption of the voltage detection circuit cannot be caused, and the reliability of the battery pack is improved. And the fault-tolerant capability and the stability of the detection circuit are improved.

Description

Technical Field

[0001] The present disclosure relates to the field of industrial control, and in particular to a voltage detection circuit and a voltage detection system for a fuel cell. Background Art

[0002] Fuel cells have a series of advantages such as high energy conversion efficiency, wide fuel sources and low emissions. They are in line with the concept of sustainable development. They are the fourth generation of power generation technology after thermal power, hydropower and nuclear power. They have broad application prospects in the fields of military, aerospace, automobiles, backup power supplies and electronic products. In the fuel cell system, the stack is the core component, which is composed of multiple single-chip cells in series. The performance of these single-chip cells directly determines the working efficiency and service life of the entire stack. In actual operation, fuel cells may degrade due to changes in various operating conditions (such as over-dryness, over-humidity, lack of air, etc.) or other mechanical damage. Therefore, real-time monitoring of the voltage of each single-chip cell has become an important means to evaluate the status of the fuel cell and ensure the stable operation of the system.

[0003] Traditional voltage detection circuits usually use a daisy chain series connection method to connect multiple voltage monitoring chips in series to detect the battery voltage. However, this connection method has some limitations. Failure of any monitoring chip in the series circuit may cause the interruption of the entire detection circuit. In addition, since the configuration of the daisy chain connection method is relatively complex, it also increases the complexity of the voltage detection circuit to a certain extent. Summary of the invention

[0004] The technical problem to be solved by the present disclosure is to overcome the defect in the prior art that a voltage monitoring chip fails, thereby causing the entire voltage detection circuit to be interrupted, and to provide a voltage detection circuit and a voltage detection system for a fuel cell.

[0005] The present invention solves the above technical problems through the following technical solutions:

[0006] In a first aspect, a voltage detection circuit of a fuel cell is provided, wherein the fuel cell comprises at least two battery packs, each battery pack comprises at least one single-chip battery, and the voltage detection circuit comprises a controller and at least two voltage monitoring modules; the voltage monitoring modules correspond one to one with the battery packs;

[0007] The different input terminals of the voltage monitoring module are respectively used to connect to the two terminals of the corresponding battery pack, and the output terminal is connected to the input terminal of the controller;

[0008] The voltage monitoring module is used to monitor the voltage data of the corresponding battery pack and transmit the voltage data to the controller.

[0009] Optionally, the voltage detection circuit further includes at least two isolation circuits; the isolation circuits correspond one-to-one to the voltage monitoring modules;

[0010] The isolation circuit is arranged between the corresponding voltage monitoring module and the controller.

[0011] Optionally, the controller includes an FPGA and an MCU;

[0012] The FPGA is communicatively connected to the MCU, the voltage monitoring module is used to transmit the voltage data to the FPGA, and the FPGA is used to process the voltage data and send the processing result to the MCU.

[0013] Optionally, the voltage monitoring module is connected to the controller via an isoSPI interface.

[0014] Optionally, the voltage monitoring module includes a voltage monitoring chip.

[0015] Optionally, the voltage detection circuit also includes a power conversion circuit; the power conversion circuit is used to connect to an external power supply, and the power conversion circuit is used to convert the voltage output by the external power supply into a target voltage and power the voltage monitoring module and the isolation circuit.

[0016] Optionally, the voltage detection circuit also includes an output circuit; the input end of the output circuit is connected to the output end of the controller, and the output circuit is used to receive a control command sent by the controller and output a corresponding switch signal in response to the control command.

[0017] Optionally, the output circuit comprises a relay, the relay is used to be connected to a disconnection device or an alarm device, and the disconnection device is used to disconnect the fuel cell from an external device.

[0018] In a second aspect, a voltage detection system for a fuel cell is provided, the voltage detection system comprising a fuel cell and the voltage detection circuit as described in the first aspect;

[0019] Optionally, the fuel cell includes at least two battery groups, each battery group includes at least one single-chip battery, and the voltage monitoring modules in the voltage detection circuit correspond one-to-one to the battery groups.

[0020] Optionally, the voltage detection system further includes a host computer; the host computer is communicatively connected to the voltage detection circuit.

[0021] On the basis of being in accordance with the common sense in the art, the above-mentioned optional conditions can be arbitrarily combined to obtain the preferred embodiments of the present disclosure.

[0022] The positive progressive effect of the present disclosure is that the input end of each voltage monitoring module is respectively used to connect to the two ends of a battery pack. Since the output end of each voltage monitoring module is connected to the input end of the controller through an independent connection line, even if one of the voltage monitoring modules in the voltage detection circuit fails, the other voltage monitoring modules can still continue to monitor the corresponding battery pack without causing the interruption of the voltage detection circuit, thereby improving the fault tolerance and stability of the detection circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a voltage detection circuit structure of a fuel cell provided in Example 1 of the present disclosure;

[0024] Figure 2 A schematic diagram of a structure including two battery packs and two voltage monitoring modules provided in Embodiment 1 of the present disclosure;

[0025] Figure 3 A schematic diagram of module connections of a voltage detection circuit provided in Embodiment 1 of the present disclosure;

[0026] Figure 4 A schematic diagram of the structure of a voltage detection circuit including five LTC6806 chips provided in Embodiment 1 of the present disclosure;

[0027] Figure 5 This is a structural block diagram of a fuel cell voltage detection system provided in Example 2 of the present disclosure. DETAILED DESCRIPTION

[0028] The present disclosure is further described below by way of examples, but the present disclosure is not limited to the scope of the examples.

[0029] Prefixes such as "first" and "second" are used in the embodiments of the present disclosure only to distinguish different description objects, and have no limiting effect on the position, order, priority, quantity or content of the described objects. The use of prefixes such as ordinal numbers to distinguish description objects in the embodiments of the present disclosure does not constitute a limitation on the described objects. For the statement of the described objects, please refer to the description in the context of the claims or embodiments, and no unnecessary limitation should be constituted due to the use of such prefixes. In addition, in the description of the present embodiment, unless otherwise specified, the meaning of "plurality" is two or more.

[0030] In the embodiments of the present disclosure, the collection, storage, use, processing, transmission, provision and disclosure of user personal information involved are in compliance with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0031] Example 1

[0032] This embodiment provides a voltage detection circuit for a fuel cell. Figure 1 As shown, the fuel cell includes at least two battery groups 101, each battery group 101 includes at least one single-chip battery, and the voltage detection circuit includes a controller 102 and at least two voltage monitoring modules 103; the voltage monitoring modules 103 correspond to the battery groups 101 one by one; the different input ends of the voltage monitoring modules 103 are respectively used to connect to the two ends of the corresponding battery group 101, and the output end is connected to the input end of the controller 102; the voltage monitoring module 103 is used to monitor the voltage data of the corresponding battery group 101, and transmit the voltage data to the controller 102.

[0033] In a specific implementation, the fuel cell is composed of multiple battery groups 101, and the multiple battery groups are connected in series. The battery group 101 is composed of multiple single-chip batteries connected in series. In the voltage detection circuit, different input ends of each voltage monitoring module 103 are used to connect to the two ends of the corresponding battery group 101. Therefore, the voltage monitoring module 103 can monitor the voltage status of each battery group 101 individually and transmit the monitored voltage data to the controller 102. Since the voltage monitoring modules 103 in the voltage detection circuit are independent, even if one of the voltage monitoring modules 103 fails, it will not affect the normal operation of other voltage monitoring modules 103 in the voltage detection circuit, thereby improving the fault tolerance and stability of the entire voltage detection circuit to a certain extent.

[0034] In a specific example, the voltage monitoring module may be configured to perform voltage monitoring on all battery packs simultaneously, or may be configured to perform voltage monitoring on some battery packs.

[0035] In another specific example, Figure 2 As shown, the fuel cell includes a first battery group 201 and a second battery group 202, and the voltage detection circuit includes a first voltage monitoring module 203 and a second voltage monitoring module 204. When the first voltage monitoring module fails, the second voltage monitoring module can still monitor the voltage of the second battery group and transmit the monitored voltage data to the controller 102, and the voltage detection circuit will not be interrupted due to the failure of the first voltage monitoring module.

[0036] In an optional implementation, the voltage detection circuit further includes at least two isolation circuits; the isolation circuits correspond one-to-one to the voltage monitoring modules; and the isolation circuits are arranged between the corresponding voltage monitoring modules and the controller.

[0037] In the specific implementation, Figure 3As shown, an isolation circuit 104 is provided between the voltage monitoring module 103 and the controller 102. The isolation circuit can prevent voltage transients that may occur in the circuit. The isolation circuit is provided between the voltage monitoring module and the controller to ensure that there is no direct electrical connection between the voltage monitoring module and the controller. The isolation circuit can not only protect the controller from damage, but also reduce noise interference and electromagnetic interference during transmission, and ensure the accuracy and stability of the voltage data received by the controller. Specifically, the isolation circuit can be a digital isolator, and each digital isolator can be individually addressed, so that the voltage monitoring modules can be connected to the controller independently of each other.

[0038] In an optional implementation, the controller includes an FPGA and an MCU; the FPGA is communicatively connected to the MCU, the voltage monitoring module is used to transmit voltage data to the FPGA, the FPGA is used to process the voltage data and send the processing results to the MCU.

[0039] In the specific implementation, Figure 3 As shown, the output end of FPGA 105 is connected to the input end of MCU 106, and the voltage monitoring module 103 transmits the voltage data collected in real time to FPGA. After receiving the voltage data from the voltage monitoring module, FPGA will filter and sample the voltage data for preprocessing, thereby removing noise and ensuring the accuracy of the voltage data. By presetting the voltage safety threshold in FPGA, when the voltage value received by FPGA exceeds the preset safety threshold, FPGA can quickly identify potential overvoltage or undervoltage problems. Once FPGA identifies an abnormal voltage value, it will immediately send the abnormal data to MCU. After receiving the abnormal data from FPGA, MCU will perform more complex data analysis, such as trend analysis, historical data comparison, etc., to further confirm whether the fuel cell has a fault and ensure the reliability of fault detection. Since FPGA can process voltage monitoring data from multiple voltage monitoring modules in parallel, through division of labor and cooperation, FPGA and MCU can achieve fast and accurate fault diagnosis, which improves the real-time and accuracy of the voltage detection circuit for the voltage detection of the fuel cell.

[0040] In a specific example, the FPGA and MCU are equipped with separate power modules for power supply, thereby ensuring that the FPGA and MCU are not affected by external power supply fluctuations when processing and analyzing voltage data, thereby improving the stability of the voltage detection circuit.

[0041] In an optional implementation, the voltage monitoring module is connected to the controller via an isoSPI interface.

[0042] In a specific implementation, the isoSPI interface is a high-speed, radio frequency interference (RFI)-resistant serial communication interface that supports long-distance communication and high-speed data transmission. Specifically, the isoSPI interface supports a data transmission rate of up to 1Mbps and can use a single twisted pair of up to 100 meters. Even if there is a long distance between the voltage monitoring module and the controller, real-time data transmission can be achieved. In addition, since the isoSPI interface has very low electromagnetic interference (EMI) sensitivity and radiation, it can maintain the clarity of the transmission signal in a noisy electromagnetic environment.

[0043] In an optional implementation, the voltage monitoring module includes a voltage monitoring chip.

[0044] In a specific implementation, the voltage monitoring chip is an integrated circuit that can be used to measure and monitor voltage signals in a circuit.

[0045] In a specific example, Figure 4 As shown, the voltage monitoring chip can be a monitoring chip of the LTC6806 model, and five LTC6806 monitoring chips are selected in the voltage detection circuit. Each LTC6806 monitoring chip is powered by an independent power supply, and does not affect each other, and the five LTC6806 monitoring chips are connected to the controller 403 through a digital isolator 402. Since each LTC6806 monitoring chip includes 36 measurement channels, that is, each LTC6806 monitoring chip can be used to connect to 36 battery packs 401 respectively, the five LTC6806 monitoring chips in the voltage detection circuit can be used to monitor the voltage of up to 180 battery packs, and since each battery pack can contain up to 4 single-chip batteries, one LTC6806 monitoring chip can be used to monitor up to 144 single-chip batteries.

[0046] In another specific example, five LTC6806 monitoring chips in a voltage detection circuit can share a power supply.

[0047] In an optional embodiment, the voltage detection circuit also includes a power conversion circuit; the power conversion circuit is used to connect to an external power supply, and the power conversion circuit is used to convert the voltage output by the external power supply into a target voltage and power the voltage monitoring module and the isolation circuit.

[0048] In a specific implementation, since the output voltage of the external power supply may fluctuate due to various reasons, such as power grid fluctuations, power supply aging, etc., the power conversion circuit can convert the output voltage of the external power supply into the required specific voltage, provide a stable input voltage for the voltage monitoring module and the isolation circuit, and maintain the voltage monitoring module and the isolation circuit to operate under the best working conditions, thereby extending the service life. At the same time, since the external power supply may introduce noise interference and electromagnetic interference, affecting the performance of the voltage monitoring module and the isolation circuit, the power conversion circuit can isolate the noise interference and electromagnetic interference generated by the external power supply, thereby improving the working performance of the voltage monitoring module and the isolation circuit.

[0049] In a specific example, the power conversion circuit uses a DC / DC converter to provide 1500 volts of electrical isolation. The DC / DC converter converts the 24V voltage provided by the external power supply into a 5V target voltage, providing a stable 5V voltage for the voltage monitoring module and the isolation circuit, protecting the voltage monitoring module and the isolation circuit from damage by high voltage. It can also prevent maintenance personnel from contacting dangerous high voltages and avoid electric shock accidents.

[0050] In another specific example, an optical coupler is provided at the input end of the power conversion circuit, and electrical isolation is achieved between the external power supply and the power conversion circuit through the optical coupler, thereby protecting the power conversion circuit from voltage fluctuations of the external power supply.

[0051] In an optional embodiment, the voltage detection circuit also includes an output circuit; the input end of the output circuit is connected to the output end of the controller, and the output circuit is used to receive a control command sent by the controller and output a corresponding switch signal in response to the control command.

[0052] In a specific implementation, the output circuit is used to receive control commands sent by the controller, which may include operation instructions such as start, stop, and adjust. The output circuit responds to the control command and outputs a corresponding switch signal, which is used to drive an external device or perform a specific operation. Specifically, when the controller sends a start command, the output circuit will output a high-level signal, usually represented by 1, which can activate the external device, such as turning on the signal light or starting the motor; when the controller sends a stop command, the output circuit will output a low-level signal, usually represented by 0, which will cause the external device to stop working, such as turning off the signal light or disconnecting the power supply.

[0053] In an optional embodiment, the output circuit includes a relay, and the relay is used to connect to a disconnection device or an alarm device, and the disconnection device is used to disconnect the fuel cell from an external device.

[0054] In a specific implementation, the relay can be used to connect to a disconnect device. When the controller identifies that an abnormal voltage appears in the battery pack of the fuel cell, the disconnect device will disconnect the circuit connection between the fuel cell and the external device to prevent the abnormal voltage from causing damage to the external device. The relay can also be used to connect to an alarm device. When the controller identifies that an abnormal voltage appears in the battery pack of the fuel cell, it will issue a control command. After receiving the control command, the relay will quickly switch the connection contacts, thereby triggering an alarm device, such as a buzzer, warning light or other alarm device, to alert the user or administrator.

[0055] Example 2

[0056] This embodiment provides a fuel cell voltage detection system. Figure 5 As shown, the voltage detection system includes a fuel cell 501 and a voltage detection circuit 502 as described in Example 1; the fuel cell includes at least two battery groups, each battery group includes at least one single-chip battery, and the voltage monitoring module in the voltage detection circuit corresponds one-to-one to the battery group.

[0057] In this embodiment, the voltage detection system can realize real-time monitoring of the fuel cell. Even if a voltage monitoring module in the voltage detection circuit fails, it will not cause the voltage detection system to fail to work normally, thereby improving the reliability and stability of the voltage detection system.

[0058] In an optional implementation, the voltage detection system further includes a host computer; the host computer is communicatively connected to the voltage detection circuit.

[0059] In a specific implementation, the host computer is usually a computing platform, such as a personal computer, a workstation or an industrial PC, which can run specific software to receive, display and analyze the voltage data transmitted by the voltage detection circuit. Figure 5 As shown, the communication between the host computer 503 and the voltage detection circuit can be achieved through the Modbus bus. The host computer can display the voltage status of the fuel cell in real time, and when the voltage detection circuit detects abnormal voltage, it can analyze the fault information through the fault diagnosis algorithm, thereby specifically displaying the faulty battery pack, which is convenient for the staff to quickly locate and repair in time to ensure the normal operation and safety of the fuel cell.

[0060] Although the specific embodiments of the present disclosure are described above, those skilled in the art should understand that this is only an example, and the protection scope of the present disclosure is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present disclosure, but these changes and modifications all fall within the protection scope of the present disclosure.

Claims

1. A voltage detection circuit for a fuel cell, characterized in that: The fuel cell comprises at least two battery packs, each battery pack comprises at least one single-chip battery, the voltage detection circuit comprises a controller and at least two voltage monitoring modules; the voltage monitoring modules correspond one to one with the battery packs; The different input terminals of the voltage monitoring module are respectively used to connect to the two terminals of the corresponding battery pack, and the output terminal is connected to the input terminal of the controller; The voltage monitoring module is used to monitor the voltage data of the corresponding battery pack and transmit the voltage data to the controller.

2. The voltage detection circuit according to claim 1, characterized in that: The voltage detection circuit also includes at least two isolation circuits; the isolation circuits correspond one to one with the voltage monitoring modules; The isolation circuit is arranged between the corresponding voltage monitoring module and the controller.

3. The voltage detection circuit according to claim 1, characterized in that: The controller includes FPGA and MCU; The FPGA is communicatively connected to the MCU, the voltage monitoring module is used to transmit the voltage data to the FPGA, and the FPGA is used to process the voltage data and send the processing result to the MCU.

4. The voltage detection circuit according to claim 1, characterized in that: The voltage monitoring module is connected to the controller via an isoSPI interface.

5. The voltage detection circuit according to claim 1, wherein: The voltage monitoring module includes a voltage monitoring chip.

6. The voltage detection circuit according to claim 2, characterized in that: The voltage detection circuit also includes a power conversion circuit; The power conversion circuit is used to connect to an external power supply, and the power conversion circuit is used to convert the voltage output by the external power supply into a target voltage, and to supply power to the voltage monitoring module and the isolation circuit.

7. The voltage detection circuit according to claim 1, characterized in that: The voltage detection circuit also includes an output circuit; The input end of the output circuit is connected to the output end of the controller. The output circuit is used to receive a control command sent by the controller and output a corresponding switch signal in response to the control command.

8. The voltage detection circuit according to claim 7, characterized in that: The output circuit includes a relay, and the relay is used to be connected to a disconnection device or an alarm device, and the disconnection device is used to disconnect the fuel cell from an external device.

9. A voltage detection system for a fuel cell, characterized in that: The voltage detection system comprises a fuel cell and a voltage detection circuit as claimed in any one of claims 1 to 8; The fuel cell comprises at least two battery groups, each of which comprises at least one single-chip battery, and the voltage monitoring modules in the voltage detection circuit correspond one-to-one to the battery groups.

10. The voltage detection system according to claim 9, characterized in that: The voltage detection system also includes a host computer; The host computer is communicatively connected with the voltage detection circuit.

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