Boost conversion control system and method thereof

Abstract

The invention provides a boost conversion control system and a method thereof, which not only can realize high step-up ratio, but also can ensure low input current ripple, high efficiency and reliability. Comprising a main topological unit used for performing boost conversion on electric energy output by a fuel cell stack assembly and then outputting the converted electric energy; the detecting and adjusting unit is used for detecting the state of the fuel cell stack assembly and adjusting and controlling the fuel cell stack assembly; the feedback adjusting unit is used for detecting the state of the main topological unit and adjusting the PWM power of the main topological unit; the FCU control end is used for adjusting and controlling the fuel cell stack assembly and the main topological unit; the main topological unit comprises at least two stages of DC-DC boost conversion modules which are arranged in series, each stage of DC-DC boost conversion module adopts n phases of BOOST circuits, and the n phases of BOOST circuits are connected in an interleaving parallel mode; and the interleaved parallel phase number of the front-stage DC-DC boost conversion module is greater than the interleaved parallel phase number of the rear-stage DC-DC boost conversion module, and n is greater than or equal to 1.

Description

Technical Field

[0001] This invention relates to the field of boost converter technology, specifically to a boost converter control system and method. Background Technology

[0002] Fuel cells are clean and efficient power generation devices. Fuel cell technology is characterized by typically low single-cell output voltage (a single stack typically outputs between 30V and 60V), and the output voltage fluctuates significantly with load changes. Therefore, to match the downstream inverter or DC bus (usually 380V or higher), a DC-DC converter capable of achieving a high boost ratio (typically >10) is needed. However, several commonly used boost converters still have the following problems: Traditional Boost converters: Their voltage gain is limited by the duty cycle. When an extremely high boost ratio is required, the duty cycle will approach 1. This will lead to extremely high stress on the switching devices, a surge in conduction losses, and serious reverse recovery problems of the diodes. The overall efficiency is extremely low and difficult to achieve. In other words, traditional Boost converters simply cannot balance efficiency and stability in high boost ratio applications. Single-stage coupled inductor or switched capacitor converters: Although they can achieve high gain, they are often accompanied by high voltage spikes and electromagnetic interference (EMI), requiring complex absorption circuits and reducing system reliability; at the same time, the design of magnetic core components is complex and the size is large; that is, high-gain converters based on single-stage coupled inductors or switched capacitors have high voltage spikes and electromagnetic interference (EMI), and the design of magnetic components is complex. Single-stage interleaved parallel boost: Interleaved parallel technology can effectively reduce input current ripple and achieve current sharing and heat dissipation of power devices, with advantages in efficiency and stability; however, under high boost ratio requirements, single-stage interleaved parallel boost is still limited by its inherent voltage gain formula, making it difficult to achieve high boost without sacrificing efficiency and stability; that is, although single-stage interleaved parallel boost converter has the advantages of efficiency and stability, it inherits all the disadvantages of traditional boost converters under high duty cycle. Two-stage cascaded converter: A simple two-stage Boost cascade can achieve high gain, but the output current ripple of the front-stage converter (i.e. the input current ripple of the rear-stage converter) is still large, which will affect the fuel cell life, have low overall efficiency, and relatively complex system dynamic response and stability control; that is, the conventional two-stage cascaded Boost converter has large front-stage current ripple, which affects the fuel cell life, has low overall efficiency and high control complexity. In addition to BOOST boost control, the normal operation of a fuel cell system also requires control of the normal operation of the fuel cell. This makes the topology of the entire fuel cell system complex and the control scheme difficult to implement. Furthermore, the components of the fuel cell control system + boost converter controller scheme are relatively separate and have low integration. Therefore, there is an urgent need in this field for a new topology of boost converter + fuel cell control (FCU) that can achieve a high boost ratio while ensuring low input current ripple, high efficiency and reliability. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a boost converter control system and method that not only achieves a high boost ratio but also ensures low input current ripple, high efficiency, and reliability.

[0004] This invention adopts the following technical solution: a boost converter control system, comprising: Fuel cell stack assembly used to generate electrical energy; The main topology unit is connected to the fuel cell stack assembly and is used to boost and convert the output power of the fuel cell stack assembly before outputting it. A detection and adjustment unit is connected to the fuel cell stack assembly and is used to detect the status of the fuel cell stack assembly and to adjust and control the fuel cell stack assembly. A feedback adjustment unit, connected to the main topology unit, is used to detect the state of the main topology unit and to adjust the PWM power of the main topology unit. The FCU control terminal is connected to both the detection and adjustment unit and the feedback adjustment unit, and is used to receive the status feedback signals from the detection and adjustment unit and the feedback adjustment unit, thereby realizing the adjustment and control of the fuel cell stack assembly and the main topology unit. The main topology unit includes at least two stages of DC-DC boost converter modules connected in series. Each stage of the DC-DC boost converter module uses an n-phase BOOST circuit, and the n-phase BOOST circuits are connected in an interleaved parallel configuration. The number of interleaved parallel phases of the preceding stage DC-DC boost converter module is greater than the number of interleaved parallel phases of the following stage DC-DC boost converter module, where n ≥ 1.

[0005] Furthermore, the main topology unit includes two-stage DC-DC boost converter modules connected in series, and is divided into a first DC-DC boost converter module and a second DC-DC boost converter module. The first DC-DC boost converter module adopts a four-phase BOOST circuit, and the second DC-DC boost converter module adopts a two-phase BOOST circuit. Both the first and second DC-DC boost converter modules adopt interleaved 360° / n phase shift control. The first DC-DC boost converter module includes a first power conversion device and a first conversion inductor. The second DC-DC boost converter module includes a second power conversion device, a second conversion inductor, and a conversion diode. Both the first and second power conversion devices use MOSFETs. Furthermore, the system also includes a lithium battery and a lithium battery BMS management module. The lithium battery is connected between the main topology unit and the lithium battery BMS management module. The lithium battery BMS management module is connected to the FCU control terminal to feed back the status of the lithium battery to the FCU control terminal. Furthermore, the detected state signals of the fuel cell stack components include, but are not limited to, stack temperature, stack single-cell voltage signal, and infeed hydrogen pressure signal; the detected state signals of the main topology unit include, but are not limited to, voltage sampling signal, current sampling signal, and temperature sampling signal during power conversion. The present invention also provides a boost converter control method, comprising the following steps: S1. Determine the output power signal of the current fuel cell stack assembly; S2. Based on the status signal of the fuel cell stack assembly, determine whether the fuel cell stack assembly is currently malfunctioning. If a malfunction exists, stop the PWM output. If no malfunction exists, the main topology unit executes the preset power boost conversion logic. S3. During the power boost conversion process, based on the status signal of the main topology unit, determine whether there is a fault in the current main topology unit. If there is a fault, stop the PWM output; if there is no fault, start the PWM output.

[0006] Furthermore, during PWM output, the FCU control terminal obtains the voltage, current, and temperature signals of the lithium battery through the lithium battery BMS management module. Based on the lithium battery status signals, the following judgments are also made: When the lithium battery voltage exceeds the charging protection threshold, the FCU control terminal adjusts the power allocation of the main topology unit through the feedback adjustment unit to reduce the charging power to the lithium battery. When the lithium battery voltage is lower than the discharge protection threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to increase the charging power of the lithium battery. When the lithium battery charging current exceeds the charging current threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to reduce the output power of the main topology unit. When the lithium battery discharge current exceeds the discharge current threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to increase the output power of the main topology unit. When the lithium battery temperature exceeds the battery temperature threshold, the FCU control unit adjusts the power distribution of the main topology unit through the feedback adjustment unit to reduce the output power of the main topology unit. Furthermore, in step S2, the fault determination of the fuel cell stack temperature includes the following steps: S2.11 When the FCU control terminal detects that the fuel cell stack temperature is higher than the fuel cell stack temperature warning value, the fuel cell stack temperature is adjusted by the detection and adjustment unit. S2.12. If the temperature still exceeds the fuel cell stack warning value after cooling adjustment, the FCU control terminal sends a power derating command to the fuel cell stack assembly. S2.13. If the maximum value of the fuel cell stack temperature warning is exceeded, the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports the fuel cell stack over-temperature fault to the host computer. Furthermore, in step S2, the fault diagnosis of the voltage of a single cell in the fuel cell stack includes the following steps: S2.21 When the FCU control terminal detects that the voltage of a single stack cell is lower than the minimum output voltage of the single cell, the FCU control terminal sends a power derating command to the fuel cell stack assembly. S2.22 If the voltage of a single stack cell is still lower than the minimum output voltage of a single cell after derating, the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports the abnormal voltage fault of the single stack cell to the host computer. Furthermore, in step S2, the fault judgment of the infeed hydrogen pressure includes: when the FCU control terminal detects an abnormal infeed hydrogen pressure, the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports the abnormal infeed hydrogen pressure fault to the host computer. Furthermore, step S3 also includes: During the power boost conversion process, the voltage, current and temperature signals of the main topology unit are sampled in real time. When any sampled signal exceeds the set protection threshold, the FCU control terminal stops the PWM output of the main topology unit and reports the power boost conversion abnormality fault to the host computer.

[0007] The beneficial effects of this invention are that, through its interleaved parallel conversion architecture, it can reduce input current ripple to protect the fuel cell, extend its service life, greatly improve power level and dynamic response, and is also more conducive to heat dissipation design. Furthermore, through its multi-stage cascaded boost architecture, it can achieve extremely high voltage gain, disperse power loss, improve the system's power level and conversion efficiency, improve the system's thermal performance and electromagnetic compatibility, and enhance the system's stability and safety, thus having good practical value. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the structure of the present invention. Detailed Implementation

[0009] like Figure 1 As shown, a boost converter control system of the present invention includes: Fuel cell stack assembly used to generate electrical energy; The main topology unit is connected to the fuel cell stack assembly and is used to boost and convert the output power of the fuel cell stack assembly before outputting it. The detection and adjustment unit is connected to the fuel cell stack assembly and is used to detect the status of the fuel cell stack assembly and to adjust and control the fuel cell stack assembly. The feedback regulation unit, connected to the main topology unit, is used to detect the status of the main topology unit and to regulate the PWM power of the main topology unit. The FCU control terminal is connected to both the detection and regulation unit and the feedback regulation unit. It is used to receive the status feedback signals from the detection and regulation unit and the feedback regulation unit, thereby realizing the regulation and control of the fuel cell stack components and the main topology unit. The main topology unit includes at least two stages of DC-DC boost converter modules connected in series. Each stage of the DC-DC boost converter module uses an n-phase BOOST circuit, and the n-phase BOOST circuits are connected in an interleaved parallel configuration. The number of interleaved parallel phases of the preceding stage DC-DC boost converter module is greater than the number of interleaved parallel phases of the following stage DC-DC boost converter module, where n≥1.

[0010] The main topology unit includes two-stage DC-DC boost converter modules connected in series, divided into a first DC-DC boost converter module and a second DC-DC boost converter module. Both the first and second DC-DC boost converter modules employ interleaved 360° / n phase shift control. If the first DC-DC boost converter module uses a four-phase BOOST circuit, then it employs interleaved 90° phase shift control; if the second DC-DC boost converter module uses a two-phase BOOST circuit, then it employs interleaved 180° phase shift control. The first DC-DC boost converter module includes first power conversion devices S1~S8 and first conversion inductors L1~L4. The second DC-DC boost converter module includes second power conversion devices S9 and S10, second conversion inductors L5 and L6, and conversion diodes D1 and D2. Both the first and second power conversion devices use MOSFETs.

[0011] The system also includes a lithium battery and a lithium battery BMS management module. The lithium battery is connected between the main topology unit and the lithium battery BMS management module. The lithium battery BMS management module is connected to the FCU control terminal to feed back the status of the lithium battery to the FCU control terminal. A fuse FU is connected to the input of the main topology unit, which protects the system from damage due to input overcurrent. The system is equipped with peripheral interfaces, such as a CAN interface. The FCU control terminal can send the operating status of the main topology unit and fuel cell stack components to the host computer in real time through the CAN interface. It can also realize the parallel connection of multiple boost converter devices through the CAN interface to achieve greater power output and reduce redundant development work.

[0012] The detected fuel cell stack component status signals include, but are not limited to, stack temperature, stack single-cell voltage signal, and infeed hydrogen pressure signal; the detected main topology unit status signals include, but are not limited to, voltage sampling signal, current sampling signal, and temperature sampling signal during power conversion.

[0013] The present invention also provides a boost converter control method, comprising the following steps: S1. Determine the output power signal of the current fuel cell stack assembly; S2. Based on the status signals of the fuel cell stack components, determine whether a fault has occurred in the current fuel cell stack components. If a fault exists, stop the PWM output and report the fault information; if no fault exists, the main topology unit executes the preset power boost conversion logic. This invention can implement multiple protection mechanisms, such as protection against overheating of the fuel cell stack, undervoltage of the fuel cell stack, and undervoltage of the input hydrogen pressure. Furthermore, in step S2, the fault determination of the fuel cell stack temperature includes the following steps: S2.11 When the FCU control terminal detects that the stack temperature is higher than the stack temperature warning value, the stack temperature is adjusted by the detection and adjustment unit, such as by adjusting the stack cooling fan speed to achieve stack cooling. S2.12. If the temperature still exceeds the fuel cell stack warning value after cooling adjustment, the FCU control terminal sends a power derating command to the fuel cell stack assembly. S2.13 If the maximum value of the fuel cell stack temperature warning is exceeded, the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports the fuel cell stack over-temperature fault to the host computer. Furthermore, in step S2, the fault diagnosis of the voltage of a single cell in the fuel cell stack includes the following steps: S2.21 When the FCU control terminal detects that the voltage of a single stack cell is lower than the minimum output voltage of the single cell, the FCU control terminal sends a power derating command to the fuel cell stack assembly. S2.22 If the voltage of a single stack cell is still lower than the minimum output voltage of a single cell after derating, the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports the abnormal voltage fault of the single stack cell to the host computer. Furthermore, excessive hydrogen pressure can cause irreparable damage to the fuel cell and may lead to safety accidents. Therefore, in step S2, the fault judgment of the hydrogen pressure entering the stack includes: when the FCU control terminal detects an abnormal hydrogen pressure entering the stack (too high or too low), the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports the abnormal hydrogen pressure entering the stack fault to the host computer. S3. During the power boost conversion process, based on the status signal of the main topology unit, determine whether there is a fault in the current main topology unit. If there is a fault, stop the PWM output and report the fault information; if there is no fault, continue the PWM output. Specifically, step S3 also includes: During the power boost conversion process, the voltage, current and temperature signals of the main topology unit are sampled in real time. When any sampled signal exceeds the set protection threshold, the FCU control terminal stops the PWM output of the main topology unit and reports the power boost conversion abnormality fault to the host computer.

[0014] Furthermore, during PWM output, the FCU control terminal obtains the voltage, current, and temperature signals of the lithium battery through the lithium battery BMS management module. Based on the lithium battery status signals, the following judgments are also made: When the lithium battery voltage exceeds the charging protection threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to reduce the charging power to the lithium battery or stop charging the lithium battery. When the lithium battery voltage is lower than the discharge protection threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to increase the charging power of the lithium battery or reduce the system output load. When the lithium battery charging current exceeds the charging current threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to reduce the output power of the main topology unit. When the lithium battery discharge current exceeds the discharge current threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to increase the output power of the main topology unit. When the lithium battery temperature exceeds the battery temperature threshold (e.g., 45°C), the FCU control unit adjusts the power distribution of the main topology unit through the feedback adjustment unit to reduce the output power of the main topology unit or to perform cooling.

[0015] This invention features a two-stage DC-DC boost converter module. The first DC-DC boost converter module employs a four-phase BOOST circuit, while the second DC-DC boost converter module employs a two-phase BOOST circuit. Both the first and second DC-DC boost converter modules utilize interleaved 360° / n phase shift control, which significantly reduces input current ripple, output capacitor current stress, and the number of capacitors, greatly improving power rating and dynamic response. It also facilitates heat dissipation design. Furthermore, the cascaded boost architecture achieves extremely high voltage gain, preventing overvoltage boost from causing a single-stage DC-DC boost converter module to operate in extreme conditions. Each stage can also be multi-phase interleaved.

[0016] Specifically, the present invention has the following technical effects: By combining multiple inductors and multiple power conversion devices in the first DC-DC boost converter module, it can adapt to a wide range of fuel cell input DC voltages and maintain high power conversion efficiency under different input voltage conditions, thus solving the problem of weak adaptability of traditional single-stage converters to fuel cell input voltage. The second DC-DC boost converter module, through the cooperation of inductors, diodes and power conversion devices, performs secondary fine regulation of electrical energy, effectively reducing output voltage ripple and improving the stability and accuracy of output voltage, meeting the application scenarios with stringent power quality requirements, such as power supply for precision electronic equipment and the integration of new energy power into the DC bus; The topology of the two-stage DC-DC boost converter module can reasonably allocate power processing tasks, and the power stress can be dispersed through the collaborative work of multiple devices, thereby improving the power density of the overall circuit. At the same time, the complementary functions and protection mechanisms of each device enhance the reliability of the circuit operation and reduce the probability of failure. The entire system of this invention adopts an FCU+DC / DC architecture, is purely digitally controlled, and can detect and provide feedback in real time. In addition to boost control, it integrates fuel cell control, features an integrated design scheme, a mature power topology, highly integrated electronic components, strong system stability, and high robustness.

[0017] In the diagram, A is an ammeter used to detect the current in its branch; V is a voltmeter used to detect the voltage in its branch.

[0018] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0019] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A boost conversion control system comprising: A fuel cell stack assembly for generating electric energy; characterized in that it further comprises: a main topology unit connected with the fuel cell stack assembly for outputting electric energy after step-up conversion; a detection and adjustment unit connected with the fuel cell stack assembly for realizing state detection of the fuel cell stack assembly and adjustment control of the fuel cell stack assembly; a feedback adjustment unit connected with the main topology unit for realizing state detection of the main topology unit and PWM power adjustment of the main topology unit; an FCU control end connected with the detection and adjustment unit and the feedback adjustment unit for receiving state feedback signals of the detection and adjustment unit and the feedback adjustment unit, and then realizing adjustment control of the fuel cell stack assembly and the main topology unit; wherein the main topology unit comprises at least two DC-DC step-up conversion modules arranged in series, each of the DC-DC step-up conversion modules adopts an n-phase BOOST circuit, and the n-phase BOOST circuits are connected in the form of interleaved parallel connection; and the number of interleaved parallel phases of the DC-DC step-up conversion module in the front stage is greater than that of the DC-DC step-up conversion module in the rear stage, and n≥1.

2. The boost conversion control system of claim 1, wherein: The main topology unit comprises two DC-DC step-up conversion modules arranged in series and divided into a first DC-DC step-up conversion module and a second DC-DC step-up conversion module, the first DC-DC step-up conversion module adopts a four-phase BOOST circuit, and the second DC-DC step-up conversion module adopts a two-phase BOOST circuit; the first DC-DC step-up conversion module and the second DC-DC step-up conversion module both adopt 360° / n interleaved phase shift control; the first DC-DC step-up conversion module comprises a first power conversion device and a first conversion inductor; the second DC-DC step-up conversion module comprises a second power conversion device, a second conversion inductor and a conversion diode; the first power conversion device and the second power conversion device both adopt MOS tubes.

3. The boost conversion control system of claim 1, wherein: The system further comprises a lithium battery and a lithium battery BMS management module, the lithium battery is connected between the main topology unit and the lithium battery BMS management module; the lithium battery BMS management module is connected with the FCU control end to feed back the state of the lithium battery to the FCU control end.

4. The boost conversion control system of claim 1, wherein: The detected state signals of the fuel cell stack assembly include but are not limited to stack temperature, stack single-piece voltage signal and hydrogen pressure signal entering the stack; the detected state signals of the main topology unit include but are not limited to voltage sampling signal, current sampling signal and temperature sampling signal during power conversion.

5. A boost conversion control method characterized by: The method comprises the following steps: S1, determining the output power signal of the current fuel cell stack assembly; S2, judging whether the current fuel cell stack assembly has a fault based on the state signal of the fuel cell stack assembly, if there is a fault, stopping PWM output, if there is no fault, the main topology unit executes a preset power step-up conversion logic; S3. During the power boost conversion process, based on the status signal of the main topology unit, determine whether there is a fault in the current main topology unit. If there is a fault, stop the PWM output; if there is no fault, start the PWM output.

6. The boost conversion control method of claim 5, wherein: When PWM is output, the FCU control terminal obtains the voltage, current, and temperature signals of the lithium battery through the lithium battery BMS management module. Based on the lithium battery status signals, the following judgments are also made: When the lithium battery voltage exceeds the charging protection threshold, the FCU control terminal adjusts the power allocation of the main topology unit through the feedback adjustment unit to reduce the charging power to the lithium battery. When the lithium battery voltage is lower than the discharge protection threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to increase the charging power of the lithium battery. When the lithium battery charging current exceeds the charging current threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to reduce the output power of the main topology unit. When the lithium battery discharge current exceeds the discharge current threshold, the FCU control terminal adjusts the power distribution of the main topology unit through the feedback adjustment unit to increase the output power of the main topology unit. When the lithium battery temperature exceeds the battery temperature threshold, the FCU control unit adjusts the power distribution of the main topology unit through the feedback adjustment unit to reduce the output power of the main topology unit.

7. The boost conversion control method of claim 5, wherein: In step S2, the fault diagnosis of the fuel cell stack temperature includes the following steps: S2.11 When the FCU control terminal detects that the fuel cell stack temperature is higher than the fuel cell stack temperature warning value, the fuel cell stack temperature is adjusted by the detection and adjustment unit. S2.

12. If the temperature still exceeds the fuel cell stack warning value after cooling adjustment, the FCU control terminal sends a power derating command to the fuel cell stack assembly. S2.13 If the maximum value of the fuel cell stack temperature warning is exceeded, the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports the fuel cell stack over-temperature fault to the host computer.

8. The boost conversion control method of claim 5, wherein: In step S2, the fault diagnosis of the voltage of a single cell in the fuel cell stack includes the following steps: S2.21 When the FCU control terminal detects that the voltage of a single stack cell is lower than the minimum output voltage of the single cell, the FCU control terminal sends a power derating command to the fuel cell stack assembly. S2.22 If the voltage of a single stack cell is still lower than the minimum output voltage of a single cell after derating, the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports a fault of abnormal voltage of a single stack cell to the host computer.

9. The boost conversion control method of claim 5, wherein: In step S2, the fault judgment of the infeed hydrogen pressure includes: when the FCU control terminal detects an abnormal infeed hydrogen pressure, the FCU control terminal sends a shutdown command to the fuel cell stack assembly and stops the PWM output of the main topology unit, and reports the abnormal infeed hydrogen pressure fault to the host computer.

10. The boost conversion control method of claim 5, wherein: In step S3, the method further includes: during the power boost conversion process, sampling the voltage signal, current signal and temperature signal of the main topology unit in real time; when any sampled signal exceeds the set protection threshold, the FCU control terminal stops the PWM output of the main topology unit and reports the power boost conversion abnormality fault to the host computer.

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