Eis sampling circuit, hydrogen fuel cell system, and vehicle
By designing an EIS sampling circuit using voltage divider and differential amplification, the problem of voltage spikes breaking down low-voltage devices is solved, enabling accurate signal analysis and improved circuit stability. This design is suitable for monitoring fuel cell stacks in hydrogen fuel cell systems and vehicles.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHINRY TECH
- Filing Date
- 2025-06-09
- Publication Date
- 2026-06-12
AI Technical Summary
The existing EIS sampling circuit suffers from voltage spikes that break down low-voltage devices due to transient analysis of the large-capacity DC blocking capacitor during low-frequency harmonic injection, causing circuit damage and affecting the stability and reliability of the fuel cell stack.
The system employs a voltage divider module and a DC blocking amplifier module. The EIS voltage signal is split into two paths by a splitting processing unit, and then differential amplification is performed by a differential amplifier unit to extract the AC component and suppress the DC component, thereby avoiding the impact of high voltage spikes on low voltage devices.
It effectively separates AC and DC components, ensuring the accuracy of signal analysis, avoiding high voltage spikes at the moment of power-on of the fuel cell stack, improving circuit stability and reliability, and enhancing the circuit's anti-interference capability and detection accuracy.
Smart Images
Figure CN224354554U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a circuit structure, and more particularly to an EIS sampling circuit, a hydrogen fuel cell system, and a vehicle. Background Technology
[0002] To ensure the proper operation of the system, including the fuel cell stack, electrochemical impedance spectroscopy (EIS) technology can be used to obtain the internal dynamics of the fuel cell stack without damaging it. During testing, a weak AC signal is applied to the stack to excite it and obtain the corresponding feedback signal. Currently, when injecting low-frequency harmonics into the system, a large-capacity DC-blocking and AC-passing capacitor is often used as a bandpass filter before further signal processing. However, in traditional circuits using DC-blocking capacitors, according to the normal power-on process, the large-capacity DC-blocking capacitor is equivalent to a short circuit in transient analysis at the moment the input relay closes upon power-up of the fuel cell stack. This results in a voltage spike as high as the input voltage after the DC-blocking capacitor, which can break down low-voltage components downstream of the capacitor, causing circuit damage. Utility Model Content
[0003] The present invention provides an EIS sampling circuit to solve the problems mentioned in the background art.
[0004] To address the aforementioned problems, in one embodiment, an EIS sampling circuit is provided, comprising a voltage divider processing module and a DC blocking amplification module. The input terminal of the DC blocking amplification module is connected to the output terminal of the voltage divider processing module. The DC blocking amplification module includes a branch processing unit and a differential amplification unit, with the output terminal of the branch processing unit connected to the input terminal of the differential amplification unit. The branch processing unit includes a first branch and a second branch, with the input terminal of the first branch connected to the input terminal of the second branch. The differential amplification unit includes a first input terminal and a second input terminal, with the output terminal of the second branch connected to the second input terminal of the differential amplification unit. The first branch includes an AC filter, with the output terminal of the AC filter connected to the first input terminal of the differential amplification unit.
[0005] Therefore, by splitting the EIS voltage signal through the splitting processing unit and then differentially amplifying the two signals through the differential amplification unit, the AC component in the signal can be effectively extracted. At the same time, the differential amplification unit can suppress common-mode signals and further filter out interference components in the EIS voltage signal, realizing the separation of AC and DC components and ensuring that the output signal contains only AC components, providing an accurate guarantee for subsequent analysis. In addition, by adopting the method of voltage division, splitting, and differential amplification, no high-voltage spike will appear at the moment of power-on of the fuel cell stack, avoiding the risk of low-voltage device breakdown and improving circuit stability and reliability.
[0006] In one embodiment, the voltage divider module includes a first resistor, a second resistor, and a first voltage follower. The input terminal of the first resistor is connected to an input signal terminal, the output terminal of the first resistor is connected to the non-inverting input terminal of the first voltage follower and the input terminal of the second resistor, the output terminal of the second resistor is connected to a ground terminal, and the output terminal of the first voltage follower is connected to the input terminals of the first branch and the second branch.
[0007] In one embodiment, the first branch further includes a second voltage follower, the non-inverting input of which is connected to the output of the AC filter, and the output of which is connected to the first input of the differential amplifier unit.
[0008] In one embodiment, the AC filter includes a first capacitor and a third resistor, the input of the third resistor being connected to the output of the first voltage follower, the output of the third resistor being connected to the non-inverting input of the second voltage follower and the input of the first capacitor, and the output of the first capacitor being connected to ground.
[0009] In one embodiment, the second branch further includes a third voltage follower, the non-inverting input of which is connected to the output of the first voltage follower, and the output of which is connected to the second input of the differential amplifier unit.
[0010] In one embodiment, the differential amplifier unit further includes an amplifier, a fourth resistor, a fifth resistor, a sixth resistor, and a seventh resistor. The input terminal of the fourth resistor is connected to the output terminal of the second voltage follower, and the output terminal of the fourth resistor is connected to the inverting input terminal of the amplifier. The input terminal of the fifth resistor is connected to the output terminal of the third voltage follower, and the output terminal of the fifth resistor is connected to the non-inverting input terminal of the amplifier. The input terminal of the sixth resistor is connected to both the inverting input terminal of the amplifier and the output terminal of the fourth resistor, and the output terminal of the sixth resistor is connected to the output terminal of the amplifier. The input terminal of the seventh resistor is connected to both the non-inverting input terminal of the amplifier and the output terminal of the fifth resistor, and the output terminal of the seventh resistor is connected to ground.
[0011] On the other hand, a hydrogen fuel cell system is provided, including a fuel cell stack, a DC-DC converter, and an EIS sampling circuit as described in any of the foregoing embodiments, wherein the output terminal of the fuel cell stack under test is connected to the input terminal of the EIS sampling circuit and the input terminal of the DC-DC converter.
[0012] On the other hand, a vehicle is provided, the vehicle including a hydrogen fuel cell system, a power battery, and a control system as described in the second aspect, wherein the output of the hydrogen fuel cell system is connected to the input of the power battery, and the hydrogen fuel cell system is connected to the input of the control system.
[0013] In one embodiment, the control system includes an MCU Fourier calculation module and a DSP control module. The input terminal of the MCU Fourier calculation module is connected to the output terminal of the EIS sampling circuit, and the output terminal of the MCU Fourier calculation module is connected to the input terminal of the DSP control module via a CAN bus.
[0014] In one embodiment, the vehicle further includes a powertrain system, which includes an XCU control module, and the output of the DSP control module is connected to the input of the XCU control module via the CAN bus.
[0015] Therefore, through the collaborative design of the split processing unit and the differential amplifier unit, the EIS voltage signal is divided into AC and DC paths for differential operation. While effectively extracting the AC component and suppressing common-mode interference to achieve AC-DC separation and provide accurate analysis signals, the voltage divider-splitter-differential amplifier method avoids the impact of high voltage spikes on low-voltage devices at the moment of power-on of the fuel cell stack, thereby improving circuit reliability and stability. Furthermore, the modular design enhances scalability and maintainability.
[0016] In hydrogen fuel cell systems and vehicle applications, this EIS sampling circuit works in deep collaboration with DC-DC converters, power batteries, MCU Fourier calculation modules, CAN bus, DSP control modules, and XCU control modules. It can process data based on the acquired signals, enabling the system to dynamically adjust output power and optimize energy distribution according to operating conditions, significantly improving the vehicle's energy efficiency, response speed, and performance. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the structure of the EIS sampling circuit in some embodiments of this application.
[0018] Figure 2 This is a partial structural diagram of the EIS sampling circuit in some embodiments of this application.
[0019] Figure 3 This is a schematic diagram of another part of the structure of the EIS sampling circuit in some embodiments of this application.
[0020] Figure 4 This is another schematic diagram of the EIS sampling circuit in some embodiments of this application.
[0021] Figure 5 This is yet another schematic diagram of the EIS sampling circuit in some embodiments of this application.
[0022] Figure 6 This is a circuit structure diagram of the EIS sampling circuit in some embodiments of this application.
[0023] Figure 7 This is a structural block diagram of a hydrogen fuel cell system in some embodiments of this application.
[0024] Figure 8 This is a structural block diagram of a vehicle in some embodiments of this application.
[0025] Figure 9 This is a structural block diagram of the vehicle control system in some embodiments of this application.
[0026] Figure 10 This is another structural block diagram of the vehicle in some embodiments of this application.
[0027] Figure 11 This is yet another structural block diagram of the vehicle in some embodiments of this application.
[0028] The reference numerals in the detailed embodiments are as follows:
[0029] EIS sampling circuit 100; voltage divider processing module 10; DC blocking amplifier module 20; branch processing unit 21; differential amplifier unit 22; first branch 211; second branch 212; AC filter 2111; first input terminal A; second input terminal B;
[0030] Amplifier A1; First voltage follower V1; Second voltage follower V2; Third voltage follower V3; First resistor R1; First capacitor C1; Second resistor R2; Third resistor R3; Fourth resistor R4; Fifth resistor R5; Ground GND; Sixth resistor R6; Seventh resistor R7;
[0031] Hydrogen fuel cell system 200; fuel cell stack 210; DC-DC converter 220; vehicle 300; power battery 310; control system 320; MCU Fourier calculation module 321; DSP control module 322; power system 330; XCU control module 331. Detailed Implementation
[0032] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.
[0033] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.
[0034] 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 this application. 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.
[0035] Please see Figure 1 , Figure 1This is a schematic diagram of the structure of the EIS sampling circuit in some embodiments of this application. In some embodiments, the EIS sampling circuit 100 includes a voltage divider processing module 10 and a DC blocking amplification module 20. The input terminal of the DC blocking amplification module 20 is connected to the output terminal of the voltage divider processing module 10. The DC blocking amplification module 20 includes a branch processing unit 21 and a differential amplification unit 22. The output terminal of the branch processing unit 21 is connected to the input terminal of the differential amplification unit 22. The branch processing unit 21 includes a first branch 211 and a second branch 212. The input terminal of the first branch 211 is connected to the input terminal of the second branch 212. The differential amplification unit 22 includes a first input terminal A and a second input terminal B. The output terminal of the first branch 211 is connected to the first input terminal A of the differential amplification unit 22, and the output terminal of the second branch 212 is connected to the second input terminal B of the differential amplification unit 22. The first branch 211 includes an AC filter 2111. The output terminal of the AC filter 2111 is connected to the first input terminal A of the differential amplification unit 22.
[0036] Thus, the EIS sampling circuit 100, through the cooperation of the voltage divider processing module 10 and the DC blocking amplifier module 20, uses the branch processing unit 21 to divide the input signal into the first branch 211 and the second branch 212, which are output to the first input terminal A and the second input terminal B of the differential amplifier unit 22, respectively. This achieves AC / DC separation of the EIS voltage signal, which can effectively extract the AC component and suppress common-mode interference through differential amplification to ensure the accuracy of signal analysis. At the same time, the multi-stage architecture of voltage divider-branch-differential amplification can avoid the impact of high voltage spikes on the devices when the fuel cell is powered on, improve the stability and reliability of the circuit, and provide a guarantee for subsequent accurate analysis and stable system operation.
[0037] Please see Figure 2 , Figure 2 This is a partial structural diagram of the EIS sampling circuit in some embodiments of this application. In some embodiments, the voltage divider processing module 10 includes a first resistor R1, a second resistor R2, and a first voltage follower V1. The input terminal of the first resistor R1 is connected to the input signal terminal, the output terminal of the first resistor R1 is connected to the non-inverting input terminal of the first voltage follower V1 and the input terminal of the second resistor R2, the output terminal of the second resistor R2 is connected to the ground terminal GND, the output terminal of the first voltage follower V1 is connected to the input terminals of the first branch 211 and the second branch 212, and the inverting input terminal of the first voltage follower V1 is connected to its output terminal.
[0038] The voltage divider processing module 10 forms a voltage divider circuit through the first resistor R1 and the second resistor R2 to proportionally reduce the voltage of the input signal, effectively preventing damage to subsequent circuits due to high voltage and improving circuit safety. The first voltage follower V1, with its high input impedance and low output impedance characteristics, can isolate interference between the preceding and following circuits, prevent signal attenuation, and enhance signal driving capability to ensure stable signal transmission. At the same time, the output of the first voltage follower V1 is connected to the first branch 211 and the second branch 212 of the branch processing unit 21, providing a stable reference for the subsequent separation and processing of the two signals, realizing accurate voltage division and buffering of the input signal, and ensuring the reliability and accuracy of the overall performance of the EIS sampling circuit 100.
[0039] Please see Figure 3 , Figure 3 This is a schematic diagram of another part of the structure of the EIS sampling circuit in some embodiments of this application. In some embodiments, the first branch 211 further includes a second voltage follower V2, the non-inverting input terminal of the second voltage follower V2 is connected to the output terminal of the AC filter 2111, the output terminal of the second voltage follower V2 is connected to the first input terminal A of the differential amplifier unit 22, and the inverting input terminal of the second voltage follower V2 is connected to its output terminal.
[0040] The branch processing unit 21, by setting a second voltage follower V2 in the first branch 211, effectively isolates the AC filter 2111 and the differential amplifier unit 22 using its high input impedance characteristics, avoiding the load effect of the subsequent circuit on the filter network and ensuring accurate extraction of the DC component. Furthermore, the AC filter 2111 is a low-pass filter. Simultaneously, the low output impedance of the second voltage follower V2 enhances the signal driving capability, enabling the filtered DC signal to be stably transmitted to the first input terminal A of the differential amplifier unit 22, reducing signal loss and distortion. In addition, this isolation effect can suppress common-mode interference, further improving the amplification efficiency of the differential amplifier unit 22 for differential-mode signals, providing a clean and reliable AC signal for subsequent EIS analysis, and significantly improving the circuit's anti-interference capability and detection accuracy.
[0041] Please see Figure 4 , Figure 4 This is another schematic diagram of the EIS sampling circuit in some embodiments of this application. In some embodiments, the AC filter 2111 includes a first capacitor C1 and a third resistor R3. The input terminal of the third resistor R3 is connected to the output terminal of the first voltage follower V1, the output terminal of the third resistor R3 is connected to the non-inverting input terminal of the second voltage follower V2 and the input terminal of the first capacitor C1, and the output terminal of the first capacitor C1 is connected to the ground terminal GND.
[0042] Since the first capacitor C1 has a small capacitive reactance to high-frequency signals, and the third resistor R3 has a certain impedance to high-frequency signals, the high-frequency signal will flow into the ground terminal GND through the first capacitor C1. Thus, the AC filter 2111 formed by the third resistor R3 and the first capacitor C1 can perform preliminary filtering on the voltage signal, filter out the AC components in the signal, suppress high-frequency interference, and retain only the relatively pure DC component in the output signal. This provides a stable DC reference for subsequent circuits and avoids interference from AC components on signal processing and system control.
[0043] Please see Figure 5 , Figure 5 This is another schematic diagram of the EIS sampling circuit in some embodiments of this application. In some embodiments, the second branch 212 further includes a third voltage follower V3, the non-inverting input terminal of the third voltage follower V3 is connected to the output terminal of the first voltage follower V1, the output terminal of the third voltage follower V3 is connected to the second input terminal of the differential amplifier unit 22, and the inverting input terminal of the third voltage follower V3 is connected to its output terminal, forming a follower structure.
[0044] The branch processing unit 21 sets a third voltage follower V3 in the second branch 212, and uses its high input impedance characteristics to directly acquire the original signal (including AC and DC mixed components) output by the first voltage follower V1, and transmits it stably to the second input terminal B of the differential amplifier unit 22 through its low output impedance characteristics, so as to provide a complete reference signal for differential operation.
[0045] Thus, through the isolation effect of the third voltage follower V3, the signal transmission of the second branch 212 is prevented from being affected by the load of the subsequent differential amplifier unit 22, ensuring that the signal input to the second input terminal B is consistent with the output signal of the voltage divider processing module 10. This forms a precise differential pair with the DC signal processed by the AC filter 2111 of the first branch 211, improving the separation efficiency and common-mode rejection capability of the differential amplifier unit 22 for AC and DC signals, and further enhancing the processing accuracy and stability of the EIS sampling circuit for complex signals.
[0046] Please see Figure 6 , Figure 6This is a circuit diagram of the EIS sampling circuit in some embodiments of this application. In some embodiments, the differential amplifier unit 22 includes amplifier A1, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, and a seventh resistor R7. The input terminal of the fourth resistor R4 is connected to the output terminal of the second voltage follower V2, and the output terminal of the fourth resistor R4 is connected to the inverting input terminal of amplifier A1. The input terminal of the fifth resistor R5 is connected to the output terminal of the third voltage follower V3 of the differential amplifier unit 22, and the output terminal of the fifth resistor R5 is connected to the non-inverting input terminal of amplifier A1. The input terminal of the sixth resistor R6 is connected to the inverting input terminal of amplifier A1 and the output terminal of the fourth resistor R4, and the output terminal of the sixth resistor R6 is connected to the output terminal of amplifier A1, forming a negative feedback loop. The input terminal of the seventh resistor R7 is connected to the non-inverting input terminal of amplifier A1 and the output terminal of the fifth resistor R5, and the output terminal of the seventh resistor R7 is connected to ground GND.
[0047] Therefore, the two signals from the first branch 211 and the second branch 212 from the branch processing unit 21 are input to the inverting input terminal and the non-inverting input terminal of the amplifier A1 through the fourth resistor R4 and the fifth resistor R5, respectively.
[0048] Wherein, let the resistance values of the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, and the seventh resistor R7 be R4, R5, R6, and R7 respectively, and let the signal output by the first branch 211 be V. in1 The signal output by the second branch 212 is V. in2 The voltage signal output by amplifier A1 is V out The voltage at the inverting input terminal of amplifier A1 is V-, and the voltage at the non-inverting input terminal is V+. Due to the "virtual open" characteristic of amplifier A1, the current through resistors R5 and R7 is equal, and the current through resistors R4 and R6 is equal. Therefore:
[0049] V+=R5 / (R5+R7)V in2 ;
[0050] V - = R4 / (R4 + R6)V in1 +R6 / (R4+R6)V out ;
[0051] Due to the "virtual short" characteristic of amplifier A1, V+ = V-. Combining the above two equations, we can obtain the formula for calculating Vout:
[0052] V out = (1 + R6 / R4)[R5 / (R5 + R7)]V in2 -R6 / R7V in1 ;
[0053] Therefore, when R4 = R7 and R5 = R6 are satisfied, the above equation can be simplified to:
[0054] V out =R6 / R4(V in2 -V in1 );
[0055] Therefore, the output signal V out The output signal V of the first branch 211 of the input in1 The signal V output from the second branch 212 in2 The difference (V) in2 -V in1 The voltage difference between the two input EIS voltage signals is directly proportional to the input voltage, with a scaling factor of R6 / R4. This amplifies the difference between the two input EIS voltage signals. By appropriately selecting the values of resistors R4 and R6, the gain of amplifier A1 can be adjusted, thereby obtaining the desired output signal V. out .
[0056] Therefore, the EIS sampling circuit of this application first uses the voltage divider processing module 10 to step down and buffer the signal (composed of the first resistor R1, the second resistor R2 and the first voltage follower V1). R1 and R2 form a voltage divider network to convert the high voltage signal into a safe range suitable for subsequent processing. The first voltage follower V1 uses its high input impedance characteristics to isolate the front and rear circuits, avoid signal attenuation, and enhances the driving capability through its low output impedance characteristics, ensuring that the signal is stably transmitted to the branch processing unit.
[0057] The branch processing unit 21 divides the signal into two differentiated processing paths, realizing AC / DC separation. The first branch 211 filters out high-frequency interference through the AC filter 2111 (which is composed of a low-pass filter structure consisting of a third resistor R3 and a first capacitor C1), retains the DC component, and outputs it to the first input terminal A of the differential amplifier unit 22 after isolation by the second voltage follower V2. The second branch 212 directly acquires the original signal (containing AC / DC mixed components) output by the voltage divider processing module 10 through the third voltage follower V3 and outputs it to the second input terminal B of the differential amplifier unit 22.
[0058] The two signals are then processed in the differential amplifier unit 22. Based on the "virtual open" and "virtual short" characteristics of the operational amplifier A1, when R4 = R7 and R5 = R6, the output signal Vout = R6 / R4(Vin2-Vin1) is amplified. This means that only the difference between the two signals (i.e. the target AC component) is amplified, effectively suppressing common-mode interference. The amplification gain can be flexibly configured by adjusting the resistance ratio of the sixth resistor R6 and the fourth resistor R4, so that the output signal can be adapted to the input range of the subsequent acquisition system.
[0059] Please see Figure 7 , Figure 7 This is a structural block diagram of a hydrogen fuel cell system according to some embodiments of this application. In some embodiments, the hydrogen fuel cell system 200 includes a fuel cell stack 210, a DC-DC converter 220, and an EIS sampling circuit 100 as described in any of the foregoing embodiments, wherein the output terminal of the fuel cell stack 210 is connected to the input terminal of the EIS sampling circuit 100 and the input terminal of the DC-DC converter 220.
[0060] Therefore, the EIS sampling circuit 100 collects the voltage signal output by the fuel cell stack 210 and uses filtering and differential amplification techniques to accurately extract the AC impedance component, thereby achieving real-time monitoring of the electrochemical process inside the fuel cell stack 210. This enables the system to detect potential faults within the fuel cell stack 210 in a timely manner, extending the fuel cell stack's service life. Simultaneously, the data output by the EIS sampling circuit 100 can be fed back to the control terminal of the DC-DC converter 220. By dynamically adjusting its conversion parameters (such as switching frequency and duty cycle), the operating point of the DC-DC converter 220 is always matched with the real-time output characteristics of the fuel cell stack 210, reducing energy loss. For example, when an increase in the internal resistance of the fuel cell stack 210 is detected, the system can automatically reduce the conversion frequency to reduce switching losses.
[0061] In addition, the multi-stage circuit configuration of voltage divider-splitter-differential amplifier enables the EIS sampling circuit 100 to effectively resist voltage spikes during the start-up / stop process of the fuel cell stack 210, avoiding the impact of high voltage on the DC-DC converter 220 and subsequent electronic equipment.
[0062] Please see Figure 8 , Figure 8 This is a structural block diagram of a vehicle according to some embodiments of this application. In some embodiments, the vehicle 300 includes a power battery 310, a control system 320, and a hydrogen fuel cell system 200 as described in any of the foregoing embodiments, wherein the output terminal of the hydrogen fuel cell system 200 is connected to the input terminal of the power battery 310, and the output terminal of the hydrogen fuel cell system 200 is connected to the input terminal of the control system 320.
[0063] In this system, the DC-DC converter 220 of the hydrogen fuel cell system 200 converts the electrical energy generated by the fuel cell stack 210 and transmits it stably to the power battery 310 to charge and store energy. The EIS sampling circuit 100 can monitor the status of the fuel cell stack 210 in real time and feed the data back to the control system 320. The latter can then precisely adjust the operating parameters of the DC-DC converter 220 to ensure that the fuel cell stack 210 is always in the high-efficiency operating range, thereby ensuring that the power battery 310 receives a stable supply of electrical energy, providing continuous power support for the vehicle 300 and improving the overall energy utilization rate.
[0064] In addition, the EIS sampling circuit 100 continuously monitors the electrochemical parameters of the battery stack 210 with high precision. Once a potential fault is detected, such as a decrease in catalyst activity or internal abnormalities, the abnormal signal can be transmitted to the control system 320. The control system 320 can respond quickly by adjusting the operating mode of the DC-DC converter 220 or limiting the output power of the battery stack 210 to avoid risks and prevent the fault from escalating. At the same time, precise monitoring and control effectively avoid damaging conditions such as overcharging and over-discharging of the power battery 310, significantly extending the service life of the entire system and reducing the maintenance cost of the vehicle 300.
[0065] Please see Figure 9 , Figure 9 This is a structural block diagram of a vehicle control system according to some embodiments of this application. In some embodiments, the control system 320 includes an MCU Fourier calculation module 321 and a DSP control module 322. The input terminal of the MCU Fourier calculation module 321 is connected to the output terminal of the EIS sampling circuit 100, and the output terminal of the MCU Fourier calculation module 321 is connected to the input terminal of the DSP control module 322 via a CAN bus.
[0066] Among them, after receiving the output signal of the EIS sampling circuit 100, the MCU Fourier calculation module 321 converts the time domain signal into frequency domain data through Fourier transform, thereby analyzing the impedance spectrum of the fuel cell stack 210, analyzing the state information of its internal electrochemical process, and providing accurate data support for system control.
[0067] The strong anti-interference capability of the CAN bus ensures stable and fast data transmission between the MCU Fourier calculation module 321 and the DSP control module 322, guaranteeing real-time information interaction even in the complex electromagnetic environment of the vehicle 300. At the same time, the DSP control module 322 generates and executes control commands based on the frequency domain analysis results of the CAN bus transmission and the operating conditions of the vehicle 300.
[0068] Please see Figure 10 , Figure 10 This is another structural block diagram of a vehicle in some embodiments of this application. In some embodiments, the vehicle 300 further includes a power system 330, which can cooperate with the control system 320 to achieve precise control of power output, improve driving stability and response speed, etc.
[0069] Please see Figure 11 , Figure 11This is another structural block diagram of a vehicle according to some embodiments of this application. In some embodiments, the power system 330 includes an XCU control module 331, and the output of the DSP control module 322 is connected to the input of the XCU control module 331 via the CAN bus.
[0070] Therefore, the DSP control module 322 transmits the processed control commands stably to the XCU control module 331 via the CAN bus. The XCU control module 331 can precisely regulate the power system 330 based on the commands, optimize the power output and energy consumption of the vehicle 300, and further improve driving smoothness and response speed. Moreover, the transmission via the CAN bus improves the reliability and timeliness of command transmission, enabling the XCU control module 331 to respond in real time to complex operating conditions, such as rapid acceleration and deceleration recovery, dynamically adjust the power distribution strategy, and enhance system stability and reliability.
[0071] In the above embodiments, the descriptions of each embodiment have their own emphasis. Parts not described in detail in a certain embodiment can be referred to in the relevant descriptions of other embodiments. The embodiments of this utility model have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this application. Furthermore, for those skilled in the art, based on the ideas of this application, there will be changes in specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the above embodiments should be included within the protection scope of the described technical solutions.
Claims
1. An EIS sampling circuit, characterized in that, include: Voltage divider processing module; A DC blocking amplification module, wherein the input terminal of the DC blocking amplification module is connected to the output terminal of the voltage divider processing module, the DC blocking amplification module includes a split processing unit and a differential amplification unit, and the output terminal of the split processing unit is connected to the input terminal of the differential amplification unit; The branch processing unit includes a first branch and a second branch. The input terminal of the first branch is connected to the input terminal of the second branch, the output terminal of the first branch is connected to the first input terminal of the differential amplifier unit, and the output terminal of the second branch is connected to the second input terminal of the differential amplifier unit. The first branch includes an AC filter, and the output terminal of the AC filter is connected to the first input terminal of the differential amplifier unit.
2. The EIS sampling circuit according to claim 1, characterized in that, The voltage divider module includes a first resistor, a second resistor, and a first voltage follower. The input terminal of the first resistor is connected to an input signal terminal. The output terminal of the first resistor is connected to the non-inverting input terminal of the first voltage follower and the input terminal of the second resistor. The output terminal of the second resistor is connected to a ground terminal. The output terminal of the first voltage follower is connected to the input terminals of the first branch and the second branch.
3. The EIS sampling circuit according to claim 2, characterized in that, The first branch also includes a second voltage follower, the non-inverting input of which is connected to the output of the AC filter, and the output of which is connected to the first input of the differential amplifier unit.
4. The EIS sampling circuit according to claim 3, characterized in that, The AC filter includes a first capacitor and a third resistor. The input terminal of the third resistor is connected to the output terminal of the first voltage follower, the output terminal of the third resistor is connected to the non-inverting input terminal of the second voltage follower and the input terminal of the first capacitor, and the output terminal of the first capacitor is connected to ground.
5. The EIS sampling circuit according to claim 3, characterized in that, The second branch also includes a third voltage follower, the non-inverting input of which is connected to the output of the first voltage follower, and the output of which is connected to the second input of the differential amplifier unit.
6. The EIS sampling circuit according to claim 5, characterized in that, The differential amplifier unit includes an amplifier, a fourth resistor, a fifth resistor, a sixth resistor, and a seventh resistor. The input terminal of the fourth resistor is connected to the output terminal of the second voltage follower, and the output terminal of the fourth resistor is connected to the inverting input terminal of the amplifier. The input terminal of the fifth resistor is connected to the output terminal of the third voltage follower, and the output terminal of the fifth resistor is connected to the non-inverting input terminal of the amplifier. The input terminal of the sixth resistor is connected to both the inverting input terminal of the amplifier and the output terminal of the fourth resistor, and the output terminal of the sixth resistor is connected to the output terminal of the amplifier. The input terminal of the seventh resistor is connected to both the non-inverting input terminal of the amplifier and the output terminal of the fifth resistor, and the output terminal of the seventh resistor is connected to ground.
7. A hydrogen fuel cell system, characterized in that, It includes a fuel cell stack, a DC-DC converter, and an EIS sampling circuit as described in any one of claims 1-6, wherein the output terminal of the fuel cell stack is connected to the input terminal of the EIS sampling circuit and the input terminal of the DC-DC converter.
8. A vehicle, characterized in that, The vehicle includes a power battery, a control system, and a hydrogen fuel cell system as described in claim 7, wherein the output of the hydrogen fuel cell system is connected to the input of the power battery, and the output of the hydrogen fuel cell system is connected to the input of the control system.
9. The vehicle according to claim 8, characterized in that, The control system includes an MCU Fourier transform calculation module and a DSP control module. The input terminal of the MCU Fourier transform calculation module is connected to the output terminal of the EIS sampling circuit, and the output terminal of the MCU Fourier transform calculation module is connected to the input terminal of the DSP control module via a CAN bus.
10. The vehicle according to claim 9, characterized in that, The vehicle also includes a powertrain system, which includes an XCU control module. The output of the DSP control module is connected to the input of the XCU control module via the CAN bus.