A fuel cell voltage acquisition precision software compensation calibration method

Abstract

The application discloses a kind of fuel cell voltage collection precision software compensation calibration method, the present application can be adjusted by updating control software or algorithm, which means that new calibration requirements or known errors can be quickly adapted, without replacing physical components, which provides higher flexibility for the system and reduces the hardware upgrade costs required due to technological progress or standard changes;The cost of the software calibration of the present application is lower, which mainly involves programming and debugging, without physical intervention, thereby saving manpower and material costs;Software adjustment can usually be completed through software updates, and the operation is relatively simple, without the need for professional calibration equipment or technical personnel to operate on site, easy to implement and maintain;Software calibration can more finely adjust calibration parameters, providing customized calibration strategies for different application scenarios or user needs, with personalized adjustment characteristics;The software calibration of the present application is lossless, and will not cause wear or damage to the hardware.

Description

Technical Field

[0001] This invention belongs to the field of fuel cells, and particularly relates to fuel cell voltage inspection. More specifically, it relates to a software compensation calibration method for fuel cell voltage acquisition accuracy. Background Technology

[0002] Currently, most commercially available hydrogen fuel cell stacks consist of hundreds of individual cells connected in series, with voltage monitors detecting the voltage of each cell. Thus, a single stack may have dozens, or even hundreds, of connecting wires to the monitor and the fuel cell for voltage acquisition. This acquisition process is necessary throughout the entire operation of the hydrogen fuel cell, from start-up to shutdown. Even with identical sampling chips, the accuracy is not entirely consistent. For example, the LTC6806 sampling chip has an error range of ±15mV, which is insufficient for practical needs. Excessive voltage acquisition error can affect the fuel cell controller's decisions. Reducing the voltage acquisition error is crucial; therefore, it is necessary to improve the error range to ±10mV or higher, requiring further optimization and compensation of each voltage acquisition channel of the voltage monitor. Methods to improve the accuracy of fuel cell voltage acquisition mainly include the following:

[0003] 1. Use a high-precision ADC (Analog-to-Digital Converter): Select an analog-to-digital converter (ADC) with high resolution and low noise.

[0004] 2. Discrete circuit optimization: For series-connected battery packs, if discrete circuits are used to sample the voltage of the upper battery, optimizing the design of these circuits, such as selecting operational amplifiers with low offset and low drift, can improve sampling accuracy.

[0005] 3. Hardware protection measures: Anti-interference design, such as shielding, grounding and using decoupling capacitors, can reduce external electromagnetic interference and maintain the purity of the acquired signal.

[0006] The methods mentioned above are all hardware optimization solutions. Hardware optimization solutions are costly, inflexible, inconvenient to upgrade, have poor timeliness, high risk, low universality, and complex to maintain. Summary of the Invention

[0007] This invention addresses the technical problems of existing hardware optimization schemes for poor sampling accuracy during fuel cell inspection, which are characterized by high cost, low flexibility, inconvenient upgrades, poor timeliness, high risk, low universality, and complex maintenance. It proposes a software compensation calibration method for fuel cell voltage acquisition accuracy.

[0008] The present invention provides a software compensation calibration method for fuel cell voltage acquisition accuracy, comprising the following steps:

[0009] Step 1: Responding to the user's trigger, the host computer starts calibration;

[0010] Step 2: The host computer sends a verification command to the CVM;

[0011] Step 3: CVM responds to the verification command. CVM verifies the received message. After successful verification, it sends the seed information to the host computer.

[0012] Step 4: After receiving the seed information sent by CVM, the host computer calculates the key information according to the security algorithm and sends it to CVM;

[0013] Step 5: After receiving the key information from the host computer, if the verification is successful, the CVM sends an acknowledgment message to the host computer; if the verification fails, the calibration ends or returns to Step 2 to start again.

[0014] Step 6: The host computer sends a stop command to the CVM, the CVM stops sending all messages and sends feedback information to the host computer;

[0015] Step 7: After receiving the feedback information, the host computer sends the target voltage to the voltage signal source. The target voltage is the desired output voltage of the voltage signal source.

[0016] Step 8: The voltage signal source outputs the target voltage and sends a message to the host computer indicating that the target voltage has been successfully set.

[0017] Step 9: The host computer sends a "Device ON" signal to the voltage signal source;

[0018] Step 10: The voltage signal source sends "Device ON" to the host computer;

[0019] Step 11: The host computer requests CVM to send the raw voltage collected;

[0020] Step 12: CVM sends a command to receive feedback and simultaneously sends the original voltage, using a periodic cyclic sending method.

[0021] Step 13: If the host computer fails to receive CVM messages for more than a preset number of consecutive times, it will report a CVM disconnection fault and calibration failure. Otherwise, continue to step 14.

[0022] Step 14: The host computer receives the original voltage message sent by CVM and the target value sent to the voltage signal source, and calculates the optimized value through the calibration algorithm;

[0023] Step 15: The host computer sends the target voltage and optimized value to CVM;

[0024] Step 16: CVM receives the target voltage and optimized value, and stores them;

[0025] Step 17: CVM sends feedback information to the host computer;

[0026] Step 18: CVM calculates the estimated voltage value using the target voltage value, the optimized value, and the acquired raw voltage value;

[0027] Step 19: The host computer requests an estimated voltage value from the CVM;

[0028] Step 20: After receiving the instruction from the host computer, CVM sends the estimated voltage value;

[0029] Step 21: After receiving the estimated voltage value, the host computer compares the estimated voltage value with the original voltage value. If the calibration result is within a reasonable range, it sends a calibration success command. The CVM then stops sending the original voltage value and the estimated voltage value and resumes sending the default message.

[0030] Step 22: The host computer sends a shutdown message to the voltage signal source;

[0031] Step 23: The voltage signal source sends a device shutdown success message to the host computer.

[0032] Preferably, in the fuel cell voltage acquisition accuracy software compensation calibration method of the present invention, in step S14, the calibration algorithm can be implemented by the following method: analyzing a large amount of data in the early stage, curve fitting, and obtaining the result through a specific algorithm formula. The input of a single sample during curve fitting is: ① the target voltage of the voltage signal source, ② the original voltage acquired by the CVM. The output of a single sample during curve fitting is the optimized value sent to the CVM. Each channel of each CVM fits a curve separately.

[0033] Preferably, in the fuel cell voltage acquisition accuracy software compensation calibration method of the present invention, in Step 21, the reasonable range is determined based on the difference between the estimated voltage value and the original voltage. When the difference is greater than the preset value, it is determined to be unreasonable; otherwise, it is reasonable.

[0034] Preferably, in the fuel cell voltage acquisition accuracy software compensation calibration method of the present invention, in Step 21, if it is not within a reasonable range, the process returns to step S14 to adjust the calibration algorithm.

[0035] Preferably, in the fuel cell voltage acquisition accuracy software compensation calibration method of the present invention, in Step 3, the seed information is a U32 random number.

[0036] Preferably, in the fuel cell voltage acquisition accuracy software compensation calibration method of the present invention, in Step 5, after the CVM receives the key information from the host computer, if the verification fails, the calibration ends or returns to Step 2 to start again.

[0037] Preferably, in the fuel cell voltage acquisition accuracy software compensation calibration method of the present invention, in Step 12, when using periodic cyclic transmission, the low byte comes first and the high byte comes last, and 4 raw voltage data are sent in each frame message.

[0038] Preferably, in the fuel cell voltage acquisition accuracy software compensation calibration method of the present invention, in Step 17, if the host computer does not receive feedback information for a preset time, it reports calibration failure.

[0039] The fuel cell voltage acquisition accuracy software compensation calibration method of the present invention adopts a software-optimized scheme, which is low in cost, more flexible, easier to upgrade, more timely, lower in risk, universally applicable, can be continuously iterated, and is easy to maintain. Attached Figure Description

[0040] Figure 1 This is a system architecture diagram of the software compensation and calibration method for fuel cell voltage acquisition accuracy according to the present invention;

[0041] Figure 2 This is a flowchart of an embodiment of the fuel cell voltage acquisition accuracy software compensation calibration method of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0043] In the description of the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. "Multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0044] Unless otherwise stated, "multiple" means two or more.

[0045] In this embodiment of the invention, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, apparatus, product or device that includes a series of steps or modules is not necessarily limited to those steps or modules that are explicitly listed, but may include other steps or modules that are not explicitly listed or that are inherent to such process, method, product or device.

[0046] The naming or numbering of steps in the embodiments of the present invention does not mean that the steps in the method flow must be executed in the time / logical order indicated by the naming or numbering. The execution order of the named or numbered process steps can be changed according to the technical purpose to be achieved, as long as the same or similar technical effect can be achieved.

[0047] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0048] refer to Figure 1 as well as Figure 2 The present invention provides a specific implementation method as follows.

[0049] This software compensation and calibration method for fuel cell voltage acquisition accuracy is mainly implemented using the following three modules: voltage signal source, host computer, and CVM (fuel cell voltage monitor). The voltage signal source, host computer, and CVM communicate with each other via CAN.

[0050] The main functions of a voltage signal source include the following:

[0051] 1. Provide a stable voltage reference: A voltage signal source can output a precise and stable voltage value as a reference point for the operation of other components in a circuit or system, ensuring the stability and reliability of the circuit.

[0052] 2. Excitation Circuit: In circuit design and testing, a voltage signal source serves as the excitation source to initiate and maintain signal transmission in the circuit, enabling the circuit to produce the expected response.

[0053] 3. Calibration and calibration: High-precision voltage signal sources are often used to calibrate and calibrate electronic measuring instruments, sensors, and other voltage sources to ensure the accuracy of measurement results from these devices.

[0054] 4. System Testing and Fault Diagnosis: By injecting a known voltage signal, the response of a circuit or system can be tested, helping to identify and locate faults, and to perform performance verification and quality control.

[0055] 5. Drive control signal: In some control systems, voltage signal sources are used as control signals to regulate the working state of the actuator.

[0056] 6. Signal Generation: As a signal generator, the voltage signal source can generate voltage signals with different waveforms (such as sine waves, square waves, triangle waves, etc.), frequencies, and amplitudes, which are used to test the frequency response, noise figure, and other characteristics of the system.

[0057] The main functions of the host computer include the following:

[0058] 1. Control command sending: The host computer can send control commands to the CVM or voltage signal source to instruct them to perform specific operations.

[0059] 2. Data Acquisition and Display: The host computer is responsible for collecting data from the CVM or voltage signal source and displaying it in real time on the user interface in the form of graphics or numerical values ​​for easy monitoring.

[0060] 3. Equipment Status Monitoring: By receiving status information transmitted from the CVM or voltage signal source, the host computer can continuously monitor the working status of the CVM or voltage signal source and promptly detect abnormalities.

[0061] 4. Data Analysis and Processing: The host computer has strong data processing capabilities, and can perform statistical analysis, anomaly detection, trend prediction, etc. on the collected data to assist in decision-making.

[0062] 5. Alarms and Notifications: Set thresholds and rules so that when the detected data exceeds the preset range, the host computer can trigger an alarm and notify relevant personnel.

[0063] 6. Data storage and management: Long-term storage of collected data to form historical records for subsequent analysis, auditing, or compliance requirements.

[0064] 7. Visualization and Reporting: Generate charts, reports, and trend analyses to intuitively display the system's operational status and help users efficiently understand complex data.

[0065] As the main module of this project, CVM's main functions include the following:

[0066] 1. Acquisition of raw voltage data.

[0067] 2. Receiving reference voltage information.

[0068] 3. Calibration algorithm calculation.

[0069] 4. Calibration information storage.

[0070] 5. Calculation of reasonable voltage data.

[0071] 6. Transmission of individual unit voltage data and comprehensive information.

[0072] The specific implementation steps of one embodiment of the present invention are as follows.

[0073] Step 1: Responding to the user's trigger, the host computer starts calibration. For example, calibration begins after the user clicks the "Start Calibration" button on the host computer.

[0074] Step 2: The host computer sends a verification command to the CVM;

[0075] Step 3: CVM responds to the verification command. CVM verifies the received message. After the verification is successful, it sends seed information to the host computer. The seed information is a U32 random number.

[0076] Step 4: After receiving the seed information sent by CVM, the host computer calculates the key information according to the security algorithm and sends it to CVM;

[0077] Step 5: After receiving the key information from the host computer, CVM verifies it and sends an confirmation message to the host computer. If the verification fails, the calibration ends or returns to Step 2 to start again.

[0078] Step 6: The host computer sends a stop command to the CVM, the CVM stops sending all messages and sends feedback information to the host computer;

[0079] Step 7: After receiving the feedback information, the host computer sends the target voltage to the voltage signal source. The target voltage is the desired output voltage of the voltage signal source.

[0080] Step 8: The voltage signal source outputs according to the target voltage and sends "Target voltage set successfully" to the host computer. The output of the voltage signal source is the voltage to be measured by the CVM, that is, the input voltage measured by the CVM.

[0081] Step 9: The host computer sends a "Device ON" signal to the voltage signal source;

[0082] Step 10: The voltage signal source sends "Device ON" to the host computer; Steps 9 and 10 confirm that both the host computer and the voltage signal source are working properly.

[0083] Step 11: The host computer requests the CVM to send the raw voltage. The raw voltage is the voltage collected by the CVM. That is, at this time, the CVM collects the target voltage mentioned above, and the collected voltage is the raw voltage.

[0084] Step 12: CVM sends instructions to receive readback feedback and simultaneously sends the raw voltage in a 200ms cycle, with the low byte first and the high byte last. Each frame sends 4 channel voltages, i.e., 4 raw voltage data.

[0085] Step 13: If the host computer fails to receive CVM messages more than 20 times in a row, it will report a CVM disconnection fault and calibration failure. Otherwise, continue to step 14.

[0086] Step 14: The host computer receives the original voltage message sent by CVM and the target value sent to the voltage signal source, and calculates the optimized value through the calibration algorithm;

[0087] The calibration algorithm can be implemented as follows: Analysis of a large amount of preliminary data, curve fitting, and the result obtained through a specific algorithm formula. The input for a single sample during curve fitting is: ① the target voltage of the voltage signal source, e.g., 0mV, 100mV, 200mV…4000mV; ② the original voltage acquired by the CVM, e.g., 0mV, 104mV, 210mV, 3994mV. The output for a single sample during curve fitting is the optimized value sent to the CVM. Each channel of each CVM individually fits a curve, and the optimized value is the difference between the original voltage and the target voltage that needs to be compensated.

[0088] Step 15: The host computer sends the target voltage and optimized value to CVM;

[0089] Step 16: CVM receives the target voltage and optimized value, and stores them;

[0090] Step 17: CVM sends feedback information to the host computer. If the host computer does not receive feedback information for more than 5 seconds, it will report a calibration failure. If the calibration fails, the current calibration will end or the process will return to Step 15 and start again.

[0091] Step 18: CVM calculates the estimated voltage value using the target voltage value, the optimized value, and the acquired original voltage value; CVM adds the optimized value to the original voltage value to obtain an estimated voltage value of the actual voltage, and outputs the estimated voltage value as the sampling result.

[0092] Step 19: The host computer requests an estimated voltage value from the CVM;

[0093] Step 20: After receiving the instruction from the host computer, CVM sends the estimated voltage value;

[0094] Step 21: After receiving the estimated voltage value, the host computer compares it with the original voltage value. If the calibration result is within a reasonable range, a calibration OK command is sent, and the CVM stops sending both the original and estimated voltage values, resuming the sending of default messages. The reasonableness is determined by the difference between the estimated and original voltage values. If the difference exceeds a preset value, the value is considered unreasonable; otherwise, it is considered reasonable. The preset value could be, for example, 6mV. If the value is outside the reasonable range, the calibration algorithm in step S14 can be adjusted to achieve the desired result, including but not limited to: more accurately removing abnormal data during data analysis, and adjusting specific algorithm formulas.

[0095] Step 22: The host computer sends a shutdown message to the voltage signal source;

[0096] Step 23: The voltage signal source sends a device shutdown success message to the host computer.

[0097] After successful calibration,

[0098] This section briefly explains the key technical aspects of the above implementation plan:

[0099] Flexibility and Updability: The system can be adjusted by updating the control software or algorithms, meaning it can quickly adapt to new calibration requirements or correct known errors without replacing physical components. This provides greater system flexibility and reduces the cost of hardware upgrades required due to technological advancements or standard changes.

[0100] Cost-effectiveness: Compared to hardware calibration, which may require specialized calibration equipment or expensive hardware replacement, software calibration is less expensive. It mainly involves programming and debugging, requiring no physical intervention, thus saving on labor and material costs.

[0101] Easy to implement and maintain: Software adjustments can usually be completed through software updates, which is relatively simple to operate and does not require professional calibration equipment or on-site technicians.

[0102] Personalized adjustments: Software calibration allows for more precise adjustments to calibration parameters, providing customized calibration strategies for different application scenarios or user needs.

[0103] Non-destructive calibration: Hardware calibration sometimes involves physical adjustments or replacement of parts, which carries operational risks. In contrast, software calibration is "non-destructive" and does not cause wear or damage to the hardware.

[0104] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method of software compensation calibration of fuel cell voltage acquisition accuracy, characterized in that, Comprising the following steps: Step1: in response to the user's trigger, the host computer starts calibration; Step2: the host computer sends a check instruction to the CVM; Step3: the CVM responds to the check instruction, and the CVM checks according to the received message, and sends seed information to the host computer after the check is passed; Step4: after the host computer receives the seed information sent by the CVM, it calculates according to the security algorithm and sends the key information to the CVM; Step5: after the CVM receives the key information of the host computer, it sends confirmation information to the host computer after the check is passed; if the check is not passed, end this calibration or return to Step2 to start again; Step6: the host computer sends a stop instruction to the CVM, and the CVM stops sending all messages and sends feedback information to the host computer; Step7: the host computer receives the feedback information and sends the target voltage to the voltage signal source, which is the expected output voltage of the voltage signal source; Step8: the voltage signal source outputs according to the target voltage and sends the target voltage setting success to the host computer; Step9: the host computer sends "device ON" to the voltage signal source; Step10: the voltage signal source sends "device ON" to the host computer; Step11: the host computer requests the CVM to send the collected raw voltage; Step12: the CVM sends back the read feedback and sends the raw voltage, which is sent in a periodic cycle; Step13: if the host computer does not receive CVM message for more than a predetermined number of times in succession, it reports CVM offline fault and calibration failure, otherwise it continues to Step14; Step14: the host computer receives the raw voltage message sent by the CVM and the target value sent to the voltage signal source, and calculates the optimized value through the calibration algorithm; Step15: the host computer sends the target voltage and the optimized value to the CVM; Step16: the CVM receives the target voltage and the optimized value and stores them; Step17: the CVM sends feedback information to the host computer; Step18: the CVM calculates the estimated voltage value through the target voltage value, the optimized value and the collected raw voltage value; Step19: the host computer requests the estimated voltage value from the CVM; Step20: the CVM receives the host computer instruction and sends the estimated voltage value; Step21: after the host computer receives the estimated voltage value, it judges the estimated voltage value and the raw voltage value, and if the calibration result is within a reasonable range, it sends a calibration success instruction, and the CVM closes the raw voltage value and the estimated voltage value and restores the default message; Step22: the host computer sends the shutdown information to the voltage signal source; Step23: the voltage signal source sends the device shutdown success information to the host computer.

2. The fuel cell voltage acquisition accuracy software compensation calibration method of claim 1, wherein, In step S14, the calibration algorithm is implemented by the following method: through a large number of data analysis in advance, curve fitting, and the results obtained by the algorithm formula, the input of a single sample in curve fitting is: ① target voltage of the voltage signal source, ② original voltage collected by the CVM, and the output of a single sample in curve fitting is the optimized value sent to the CVM, and a curve is fitted for each channel of each CVM.

3. The method of claim 1, wherein the method further comprises: In step 21, whether the range is reasonable is judged according to the difference between the estimated voltage value and the original voltage, and when the difference is greater than a preset value, it is judged that the range is unreasonable, otherwise it is reasonable.

4. The method of claim 1, wherein, In step 21, if it is not in the reasonable range, step S14 is returned to adjust the calibration algorithm.

5. The method of claim 1, wherein, In step 3, the seed information is a U32 random number.

6. The method of claim 1, wherein, In step 5, after the CVM receives the key information of the upper computer, if the verification fails, the calibration is ended or step 2 is returned to start again.

7. The method of claim 1, wherein, In step 12, when the period cycle is sent, the low byte is in front and the high byte is in back, and four original voltage data are sent in each frame of message.

8. The method of claim 1, wherein, In step 17, the upper computer does not receive the feedback information within a preset time, and reports that the calibration fails.

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