Fuel Cell Integrated Control System and Method

Abstract

The present application discloses a fuel cell integrated control system and method. The system includes a DC / DC controller power module, an air compressor controller power module, and a control system main control module; the DC / DC controller power module includes a voltage conversion circuit, a power grid interface, and a fuel cell interface, and the voltage conversion circuit includes an inductor, a first switch, and a first switching tube; the air compressor controller power module includes an air compressor control circuit and a power battery interface. When the voltage conversion circuit is connected to the power grid interface and the first switch is switched to connect to the air compressor control circuit, the inductor in the voltage conversion circuit and the air compressor control circuit form a PFC circuit, and the power battery interface is connected, so that the fuel cell integrated control system can charge the power battery. The system can realize the charging of the power battery in the fuel cell control system without additionally adding a PFC circuit module, and can effectively reduce the problems of excessive burden on the cost, volume, weight, etc. of the fuel cell control system.

Description

Technical Field

[0001] This application relates to the field of new energy technologies, and in particular, to a fuel cell integrated control system and method. Background Art

[0002] Due to its many advantages, hydrogen fuel cell vehicles have increasingly become a key research direction in the field of new energy vehicles. However, when a hydrogen fuel electric vehicle is unable to obtain hydrogen fuel or the hydrogen fuel cell fails, the new energy vehicle needs to charge the power battery to achieve endurance. However, the method of combining a fuel cell and a power battery greatly increases the burden on the original hydrogen fuel cell system, and will significantly increase problems such as the cost, volume, and weight of the hydrogen fuel cell system. Summary of the Invention

[0003] In view of this, embodiments of this application provide a fuel cell integrated control system and method to solve the problem of excessive burden on the hydrogen fuel cell system caused by combining a fuel cell and a power battery.

[0004] In a first aspect, embodiments of this application provide a fuel cell integrated control system, including:

[0005] A DC / DC controller power module, an air compressor controller power module, and a control system main control module;

[0006] The DC / DC controller power module includes a voltage conversion circuit, a power grid interface, and a fuel cell interface. The voltage conversion circuit includes an inductor, a first switch, and a first switching tube. The first switch is used to switch the inductor to connect to the first switching tube or to connect to the air compressor control circuit. The DC / DC controller power module further includes a second switch, and the second switch is used to switch the inductor in the voltage conversion circuit to connect to the fuel cell interface or to connect to the power grid interface;

[0007] The air compressor controller power module includes the air compressor control circuit and a power battery interface. When the voltage conversion circuit connects to the power grid interface and the first switch switches to connect to the air compressor control circuit, the inductor in the voltage conversion circuit and the air compressor control circuit form a PFC circuit, and the power battery interface is connected, so that the fuel cell integrated control system can charge the power battery.

[0008] In the above aspect and any possible implementation manner, a further implementation manner is provided. The first switch includes at least two switching connection ports. When the first switch connects to the first switching connection port, the first switch connects the inductor and the first switching tube; when the first switch connects to the second switching connection port, the first switch connects the inductor and the second switching tube.

[0009] For the aspects and any possible implementation manners described above, a further implementation manner is provided. The DC / DC controller power module employs at least two parallel-connected voltage transformation circuits, and the number of the first switches and the first switching tubes is the same as the number of the voltage transformation circuits.

[0010] For the aspects and any possible implementation manners described above, a further implementation manner is provided. The main control module of the control system includes a sampling circuit, a digital control unit, and a driving circuit.

[0011] The sampling circuit is used to sample the voltage / current signals of the voltage transformation circuit and the air compressor control circuit.

[0012] The digital control unit is used to receive the control commands issued by the host computer and send control signals to the voltage transformation circuit and the air compressor control circuit through the driving circuit. The control signals include PWM signals and the switch control signals.

[0013] For the aspects and any possible implementation manners described above, a further implementation manner is provided. When the voltage transformation circuit is connected to the fuel cell interface, the sampling circuit samples the voltage / current signals of the voltage transformation circuit and the air compressor control circuit.

[0014] The digital control unit receives the target current signal, determines the control signal through the PI regulator, and makes the input current of the voltage transformation circuit equal to the target current by issuing the control signal.

[0015] The digital control unit receives the target speed signal, determines the control signal through the PI regulator, and makes the speed of the air compressor reach the target speed by issuing the control signal.

[0016] For the aspects and any possible implementation manners described above, a further implementation manner is provided. When the voltage transformation circuit is connected to the power grid interface, the sampling circuit samples the voltage / current signals of the voltage transformation circuit and the air compressor control circuit.

[0017] The digital control unit receives the target voltage signal, determines the control signal through the PI regulator, and makes the input voltage of the voltage transformation circuit equal to the target voltage by issuing the control signal.

[0018] For the aspects and any possible implementation manners described above, a further implementation manner is provided. The first switching tube employs a silicon carbide MOSFET switching tube.

[0019] For the aspects and any possible implementation manners described above, a further implementation manner is provided. The power grid interface is a three-phase power grid interface.

[0020] In a second aspect, an embodiment of the present application provides a fuel cell integrated control method, including the following steps performed by a fuel cell integrated control system:

[0021] The main control module of the control system obtains a charging instruction;

[0022] The power module of the DC / DC controller turns on the inductor in the air compressor control circuit and the transformer circuit according to the charging instruction;

[0023] The power module of the DC / DC controller turns on the inductor in the grid interface and the transformer circuit according to the charging instruction, and turns on the power battery interface, so that the inductor in the transformer circuit and the air compressor control circuit form a PFC circuit;

[0024] The main control module of the control system obtains a charging voltage;

[0025] The power module of the DC / DC controller and the power module of the air compressor controller output the charging voltage through the PFC circuit according to the charging voltage, where the fuel cell integrated control system is the fuel cell integrated control system as described in the first aspect.

[0026] Further, the main control module of the control system includes a sampling circuit, a digital control unit, and a driving circuit.

[0027] In the aspect and any possible implementation manner as described above, a further implementation manner is provided. The power module of the DC / DC controller and the power module of the air compressor controller output the charging voltage through the PFC circuit, including:

[0028] The power module of the DC / DC controller and the power module of the air compressor controller obtain the voltage / current signal of the PFC circuit through the sampling circuit;

[0029] The digital control unit receives a control command, where the control command is sent by the host computer to the digital control unit according to the charging voltage and the voltage / current signal of the PFC circuit;

[0030] The digital control unit sends a control signal to the power module of the DC / DC controller and the power module of the air compressor controller through the driving circuit according to the received control command, so that the power module of the DC / DC controller and the power module of the air compressor controller output the charging voltage according to the control signal.

[0031] In an embodiment of the present application, a fuel cell integrated control system is provided. The fuel cell integrated control system includes a DC / DC controller power module, an air compressor controller power module, and a control system main control module. Among them, when the first switch on the DC / DC controller power module is switched on to the air compressor control circuit, and the second switch switches the voltage conversion circuit to connect to the power grid interface, the inductor in the voltage conversion circuit and the air compressor control circuit are connected to form a PFC circuit, and the power grid interface is connected to the power battery interface. Through the formed PFC circuit, the control system main control module can keep the PFC circuit at a constant voltage input by inputting a control signal to achieve charging of the power battery. The embodiment of the present application integrates the voltage conversion function of DC / DC and the air compressor speed control function, and can realize power battery charging in the fuel cell control system without adding an additional PFC circuit module, which can effectively reduce the problems of excessive cost, volume, and weight of the fuel cell control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 is a circuit schematic diagram of a fuel cell integrated control system in an embodiment of the present application;

[0034] Figure 2 is a circuit schematic diagram of a fuel cell integrated control system in a normal mode in an embodiment of the present application;

[0035] Figure 3 is a control loop schematic diagram of outputting the PWM_Q1, PWM_Q2, and PWM_Q3 control signals of the first switching tube through a PI regulator in an embodiment of the present application;

[0036] Figure 4 is a control loop schematic diagram of outputting the PWM_QA1, PWM_QA2, PWM_QB1, PWM_QB2, PWM_QC1, and PWM_QC2 control signals of the second switching tube through a PI regulator in a normal mode in an embodiment of the present application;

[0037] Figure 5 is a circuit schematic diagram of a fuel cell integrated control system in a charging mode in an embodiment of the present application;

[0038] Figure 6This is a schematic diagram of a control loop that outputs the PWM_QA1, PWM_QA2, PWM_QB1, PWM_QB2, PWM_QC1, and PWM_QC2 control signals of the second switching tube through a PI regulator in a charging mode in an embodiment of the present application. Detailed implementation manners

[0039] To better understand the technical solution of the present application, the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0040] It should be clear that the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application.

[0041] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms of "a", "this", and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0042] It should be understood that the term " / and / " used herein is only a description of the same field of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0043] It should be understood that although terms such as first, second, and third may be used in the embodiments of the present application to describe preset ranges, etc., these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from each other. For example, without departing from the scope of the embodiments of the present application, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0044] Depending on the context, the word "if" as used herein can be interpreted as "when" or "while" or "in response to determining" or "in response to detecting". Similarly, depending on the context, the phrase "if determined" or "if detecting (stated condition or event)" can be interpreted as "when determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)".

[0045] The present application provides a fuel cell integrated control system, which has a grid charging function and includes the following three modules:

[0046] DC / DC controller power module, air compressor controller power module, and control system main control module.

[0047] Among them, the DC / DC (Direct Current Direct Current Converter) controller power module is used to control the electric power of the fuel cell integrated control system. The air compressor controller power module is used to control the output current of the fuel cell to adjust the power output of the entire system, and to adjust the air intake of the fuel cell by adjusting the rotational speed of the air compressor motor. The control system main control module is used to receive the target command and send control signals to the DC / DC controller power module and the air compressor controller power module through a regulator (such as a PI regulator), so as to achieve the purpose that the output voltage / current of the DC / DC controller power module and the air compressor controller power module reaches the target voltage / current output.

[0048] Specifically, the DC / DC controller power module includes a voltage conversion circuit, a power grid interface, and a fuel cell interface. The voltage conversion circuit includes an inductor, a first switch, and a first switching tube. The first switch is used to switch the inductor to connect to the first switching tube or to connect to the air compressor control circuit. The DC / DC controller power module also includes a second switch, which is used to switch the voltage conversion circuit to connect to the fuel cell interface or to connect to the power grid interface.

[0049] Among them, the voltage conversion circuit can specifically adopt three boost voltage conversion circuits in parallel. Among them, one boost voltage conversion circuit can include an inductor, a first switching tube, and a diode. The first switching tube uses a silicon carbide MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) switching tube, and its control signal is sent and controlled by the control system main control module. Adopting a parallel structure can improve the power capacity of the system, and adopting a silicon carbide MOSFET switching tube can increase the switching frequency, achieve low-resistance conduction, and have effects such as high temperature resistance and high voltage resistance.

[0050] Among them, the grid interface can specifically be a three-phase grid interface. A new energy vehicle equipped with a fuel cell and a power battery can achieve the charging function of the power battery by accessing the three-phase grid interface. The power module of the DC / DC controller further includes a fuel cell interface and a second switch. The second switch can specifically be an open-close switch. For example, when the second switch is in the closed state, the voltage conversion circuit is connected to the fuel cell interface, and at this time, the voltage conversion circuit is used to control the input current of the power module of the DC / DC controller; when the second switch is in the open state, the voltage conversion circuit is connected to the grid interface, and at this time, the inductor in the voltage conversion circuit and the air compressor control circuit form a PFC circuit to control the constant voltage output of the power module of the DC / DC controller, so that the power battery can be charged on a constant voltage circuit with a specified voltage.

[0051] The power module of the DC / DC controller further includes a first switch, which is used to switch the connection of the inductor to the first switch tube or to the air compressor control circuit. When the first switch is switched to connect to the first switch tube, the power module of the DC / DC controller operates in fuel cell power generation; when the first switch is switched to connect to the air compressor control circuit, the power module of the DC / DC controller operates in the constant voltage charging of a PFC (Power Factor Correction) circuit.

[0052] Specifically, the power module of the air compressor controller includes an air compressor control circuit and a power battery interface. When the voltage conversion circuit is connected to the grid interface and the first switch is switched to connect to the air compressor control circuit, the inductor in the voltage conversion circuit and the air compressor control circuit form a PFC circuit, and the power battery interface is connected, so that the fuel cell integrated control system can charge the power battery.

[0053] Furthermore, the first switch includes at least two switching connection ports. When the first switch is connected to the first switching connection port, the first switch connects the inductor and the first switch tube; when the first switch is connected to the second switching connection port, the first switch connects the inductor and the second switch tube.

[0054] Understandably, the first switch can be a multi-way switch, for example, the first switch can be a two-way switch. When the first switch is switched, the inductor and the first switching transistor are correspondingly switched to be turned on, or the inductor and the second switching transistor are switched to be turned on. It should be noted that after the inductor and the second switching transistor are turned on, on the premise that the second switch is connected to the power grid interface, the current of the DC / DC controller power module flows to the air compressor controller power module, forming a PFC circuit. By the control signal sent by the main control module of the control system, a constant voltage can be controlled to charge the power battery. Compared with the prior art, new energy vehicles carrying power batteries directly add a PFC circuit module to achieve power battery charging, which will significantly increase the burden on the cost, volume, weight, etc. of the fuel cell system. In this application, the fuel cell integrated control system adopted does not need to add an additional AC charging circuit. The power grid charges the battery through the combination of the air compressor controller power module and the DC / DC controller power module. On the basis of using the DC / DC controller power module and the air compressor controller power module, a PFC circuit is formed to charge the power battery by changing the circuit connection method, without adding an additional PFC circuit module.

[0055] Furthermore, the number of the first switches and the first switching transistors of the DC / DC controller power module is the same as the number of the voltage conversion circuits. Specifically, each voltage conversion circuit may include one or more inductor elements, and each voltage conversion circuit is in a parallel relationship. Adopting this circuit connection method can improve the power capacity of the fuel cell integrated control system. There can be multiple first switches, each voltage conversion circuit can correspond to a first switch, and each first switch can correspond to a first switching transistor. Understandably, the first switching transistor can control the current / voltage of the DC / DC by receiving the control signal sent by the main control module of the control system. During fuel cell discharge and when charging the power battery, the current / voltage of the circuit can be accurately controlled.

[0056] Furthermore, the air compressor control circuit is an inverter bridge circuit, including a second switching transistor, and the second switching transistor can adopt a MOSFET switching transistor. Specifically, when the power grid interface is a three-phase interface, the air compressor control circuit can specifically be a three-phase inverter bridge circuit. The inverter bridge circuit includes a second switching transistor, which can specifically be a silicon carbide MOSFET switching transistor.

[0057] Furthermore, the main control module of the control system includes a sampling circuit, a digital control unit, and a driving circuit; the sampling circuit is used to sample the voltage / current signals of the voltage conversion circuit and the air compressor control circuit; the digital control unit (specifically, it can be a digital control chip) is used to receive the control commands issued by the host computer and send control signals to the voltage conversion circuit and the air compressor control circuit through the driving circuit. The control signals include PWM (Pulse Width Modulation) signals and related switch control signals. Among them, the switch control signal can perform corresponding switch control operations according to the PWM signal.

[0058] It can be understood that the main control module of the control system is a module that controls the power module of the DC / DC controller and the power module of the air compressor controller. Specifically, it can first perform circuit detection on the voltage conversion circuit and the air compressor control circuit to obtain the input / output voltage / current information, and then perform control intervention on the voltage conversion circuit and the air compressor control circuit through the control commands issued by the host computer, so that the input / output current / voltage meets the expectations.

[0059] Furthermore, when the voltage conversion circuit is connected to the fuel cell interface, the sampling circuit samples the voltage / current signals of the voltage conversion circuit and the air compressor control circuit; the digital control unit receives the target current signal, determines the control signal through the PI regulator, and makes the input current of the voltage conversion circuit equal to the target current by sending the control signal; the digital control unit receives the target speed signal, determines the control signal through the PI regulator, and makes the speed of the air compressor reach the target speed by sending the control signal. It can be understood that when the fuel cell integrated control system is in the state of fuel cell power generation, the purpose of this control system is to control the input current of the voltage conversion circuit and the speed of the air compressor. After receiving the target current signal and the target speed signal sent by the host computer, the digital control unit uses the PI regulator to adjust and control the input current of the voltage conversion circuit and the speed of the air compressor, so that the input current of the voltage conversion circuit is as close as possible to the target current, and the speed of the air compressor is as close as possible to the target speed.

[0060] Furthermore, when the voltage conversion circuit is connected to the grid interface, the sampling circuit samples the voltage / current signals of the voltage conversion circuit and the air compressor control circuit; the digital control unit receives the target voltage signal, determines the control signal through the PI regulator, and makes the input voltage of the voltage conversion circuit equal to the target voltage by sending the control signal. It can be understood that when the fuel cell integrated control system is in the state of power battery charging, the current goal is to make the power module of the DC / DC controller output a constant target voltage. Specifically, after the current / voltage sampling, the driving circuit sends the control signal determined by the PI regulator to the power module of the DC / DC controller to output a constant target voltage on this fuel cell integrated control system.

[0061] Figure 1 It is a circuit schematic diagram of a fuel cell integrated control system in an embodiment of the present application. As Figure 1 shown, the fuel cell integrated control system includes a DC / DC controller power module, an air compressor controller power module, and a control system main control module.

[0062] Among them, the DC / DC controller power module includes a three-phase power grid interface, a fuel cell interface, and a voltage conversion circuit. The three-phase power grid interface is connected to the voltage conversion circuit. One end of the fuel cell interface is connected to one end of the second switch S5, and the other end of the fuel cell interface is grounded. The voltage conversion circuit includes inductors L1, L2, and L3. Each inductor is in a parallel relationship in the circuit. Each inductor corresponds to a first switch, which are switch S1 corresponding to inductor L1, switch S2 corresponding to inductor L2, and switch S3 corresponding to inductor L3. Each first switch corresponds to a first switch tube, which are switch S1 corresponding to first switch tube Q1, switch S2 corresponding to first switch tube Q2, and switch S3 corresponding to first switch tube Q3. Each first switch has two connection ports. One connection port is used to connect the first switch tube, and the other connection port is used to connect the air compressor control circuit. Each first switch tube is connected in series with a diode, which are diodes D1, D2, and D3 respectively. GND represents ground. The DC / DC controller power module also includes second switches, which are switches S4 and S5. One end of switch S4 is connected to the three-phase power grid interface, and the other end of switch S4 is connected to the other end of switch S5.

[0063] Among them, the air compressor controller power module includes an air compressor control circuit and a power battery interface. The air compressor control circuit can specifically be a three-phase inverter bridge circuit. As Figure 2 shown, the three-phase inverter bridge circuit includes 6 second switch tubes (which are QA1, QA2, QB1, QB2, QC1, and QC2) and a capacitor C1. The two ends of the power battery interface are connected to the three-phase inverter bridge circuit. The air compressor motor interface is the load interface of the three-phase inverter bridge circuit for connecting the air compressor.

[0064] Among them, the main control module of the control system is an integrated control module that can sample signals from the DC / DC controller power module and the air compressor controller power module. After communicating with the external CAN (Controller Area Network), it sends control signals to the DC / DC controller power module and the air compressor controller power module. Specifically, the sampled signals can include three-phase voltage sampling signals, three-phase current sampling signals, and bus voltage sampling signals. The control signals can be control signals sent to switches S1, S2, S3, S4, and S5, as well as control signals sent to the first MOSFET switches (Q1, Q2, Q3) on the voltage conversion circuit, and control signals sent to the second MOSFET switches (QA1, QA2, QB1, QB2, QC1, QC2) of the air compressor controller.

[0065] As Figure 1 shown, the opening and closing of switches S4 and S5 will determine whether the interface connected to the DC / DC controller power module is a three-phase power grid interface or a fuel cell interface. Switches S1, S2, and S3 have two alternative routes, namely the routes for connecting to the first switches (Q1, Q2, Q3) and the second switches (QA1, QA2, QB1, QB2, QC1, QC2). In the embodiment of the present application, the DC / DC controller power module and the air compressor controller power module are integrated in the fuel cell integrated control system, and the voltage conversion circuit and the air compressor control circuit are associated through the first switch and the second switch. When the electric battery needs to be charged, a PFC circuit is formed based on the inductor in the voltage conversion circuit and the air compressor control circuit. Without adding an additional PFC circuit module, the electric battery charging function can be realized, effectively reducing problems such as excessive cost, volume, and weight of the fuel cell integrated control system.

[0066] In one embodiment, based on Figure 1 , switches S4 and S5 are closed to switch the first switches (S1, S2, S3) to connect the inductor to the first MOSFET switches (Q1, Q2, Q3) on the voltage conversion circuit. At this time, it is the normal (fuel cell discharging) mode of the fuel cell integrated control system. Specifically, Figure 2 is a circuit schematic diagram of a fuel cell integrated control system in the normal mode in the embodiment of the present application. As Figure 2As shown, the DC / DC controller power module is connected to the fuel cell interface, and the inductor is connected to the first switching transistor. The digital control unit may specifically include a stack circuit control module and an air compressor speed control module. Specifically, the main control module of the control system samples the inductor current through a sampling circuit and samples the air compressor current through the sampling circuit. Then, based on the control commands received by the stack circuit control module and the air compressor speed control module respectively, the main control module of the control system outputs the PWM_Q1, PWM_Q2, PWM_Q3 control signals for controlling the first switching transistor of the transformer circuit and the PWM_QA1, PWM_QA2, PWM_QB1, PWM_QB2, PWM_QC1, PWM_QC2 control signals for controlling the second switching transistor of the air compressor control circuit by controlling the drive circuit of the MOSFET.

[0067] Figure 3 It is a schematic diagram of a control loop for outputting the PWM_Q1, PWM_Q1, PWM_Q1 control signals of the first switching transistor through a PI regulator in an embodiment of the present application.

[0068] Among them, Icmd is the command of the target current received through CAN communication. After dividing Icmd by 3, it is used as the reference for the three-way inductor current control loop. Il1samp, Il2samp, and Il3samp are the three-way boost inductor current values collected by the sampling circuit and used as the feedback values of the control loop. Finally, the PWM control signals, namely PWM_Q1, PWM_Q2, and PWM_Q3, are output. Among them, the PI regulator can adjust the passing current, compare the given target current command with the actual output current to obtain an error, and use this error to make the current input next time as close as possible to the target current to achieve the purpose of adjusting and controlling the current. PWM can change the width or duty cycle of the pulse according to the output of the PI regulator, so that the PWM_Q1, PWM_Q2, and PWM_Q3 control signals of the first switching transistor achieve the effect of current regulation and make the input current closer to the target current.

[0069] Figure 4 It is a schematic diagram of a control loop for outputting the PWM_QA1, PWM_QA2, PWM_QB1, PWM_QB2, PWM_QC1, PWM_QC2 control signals of the second switching transistor through a PI regulator in the normal mode in an embodiment of the present application.

[0070] As Figure 4As shown in the figure, a PI regulator is used as the signal feedback device. Specifically, the main control module of the control system receives the rotational speed setting Wset transmitted through CAN communication. The signal value of the rotational speed setting Wset is input into the PI regulator of one branch. Additionally, the rotational speed setting Wset is transmitted to another branch and compared with the current actual rotational speed W of the air compressor. The rotation angle theta is obtained through the current sampling Iasamp, Ibsamp, and Icsamp and the motor rotation angle observation algorithm. Then, through the dq transformation (also known as Park's Transformation, a commonly used coordinate transformation for analyzing the operation of synchronous motors), iq (the current in the q-axis direction in the d-q coordinate system) and id (the current in the d-axis direction in the d-q coordinate system) are obtained. iq is connected to the branch where the PI regulator directly transmitted by the rotational speed setting Wset and undergoes another PI adjustment. id directly undergoes a PI adjustment. Finally, the dq inverse transformation is performed on the outputs after PI adjustment of iq and id and the rotation angle theta to obtain the control signal based on three-phase svpwm (Space Vector Pulse Width Modulation), including the PWM_QA1, PWM_QA2, PWM_QB1, PWM_QB2, PWM_QC1, and PWM_QC2 control signals of the second switching tube.

[0071] In the discharge mode of the fuel cell, the voltage transformation circuit of the DC / DC controller power module and the inverter bridge circuit of the air compressor controller power module can control the input current of the DC / DC and the rotational speed of the air compressor motor near the preset values.

[0072] Figure 5 It is a circuit schematic diagram of a fuel cell integrated control system in the charging mode in an embodiment of the present application. When the fuel cell integrated control system is in the charging mode, the hydrogen fuel cell stack stops working and charges the power battery at a constant voltage through the three-phase power grid interface.

[0073] As Figure 5As shown, the second switch S4 and the second switch S5 are disconnected, and the first switch S1, the first switch S2, and the first switch S3 are connected to turn on the second switching tube of the air compressor controller power module. The power battery interface is connected to the second switching tube, and forms a PFC circuit with the inductor in the voltage transformation circuit of the DC / DC controller power module. At this time, the main control module of the control system performs PFC charging control, samples the three-phase voltage and three-phase current, and samples the battery voltage input to the power battery interface. The main control module of the control system outputs control signals PWM_QA1, PWM_QA2, PWM_QB1, PWM_QB2, PWM_QC1, and PWM_QC2 for controlling the second switching tube by adjusting the PWM signal, so as to realize the constant voltage control of the PFC circuit and the charging function of the power battery.

[0074] Figure 6 It is a schematic diagram of the control loop for outputting control signals PWM_QA1, PWM_QA2, PWM_QB1, PWM_QB2, PWM_QC1, and PWM_QC2 of the second switching tube through a PI regulator in the charging mode in an embodiment of the present application. The implementation logic of this control loop can be referred to Figure 4 for the description. The main difference is that the inputs of the control loop are the charging voltage setting Vset and the sampled battery voltage Vsamp, and the phase angle theta obtained through the three-phase voltage sampling Vasamp, Vbsamp, and Vcsamp through the phase-locked loop. As Figure 6 shown, the charging voltage setting Vset and the sampled battery voltage are used as the inputs of the control loop and first perform a PI adjustment; the phase angle theta obtained by the three-phase voltage sampling Vasamp, Vbsamp, and Vcsamp through the phase-locked loop and the current sampling Iasamp, Ibsamp, and Icsamp are subjected to dq transformation to obtain iq and id. Then, iq and the charging voltage setting Vset and the sampled battery voltage after PI adjustment are used as inputs to perform a PI adjustment again to obtain a first output value; id is separately subjected to a PI adjustment to obtain a second output value. Finally, based on the first output value, the second output value, and the phase angle theta, a dq inverse transformation is performed to obtain the control signals based on three-phase svpwm, including the control signals PWM_QA1, PWM_QA2, PWM_QB1, PWM_QB2, PWM_QC1, and PWM_QC2 of the second switching tube.

[0075] From Figure 2 and Figure 5As can be seen, in the circuit module integrating the DC / DC controller power module and the air compressor controller power module in this application, by adjusting the first switch and the second switch, flexible switching between the normal mode and the charging mode can be achieved. Especially in the charging mode, when the second switch S4 and the second switch S5 are disconnected, and the first switch S1, the first switch S2, and the first switch S3 connect the inductor to the second switching tube of the air compressor controller power module, the inductor in the voltage conversion circuit and the air compressor control circuit form a PFC circuit, enabling the charging function of the power battery without the need to additionally add a PFC circuit module.

[0076] In the embodiment of this application, a fuel cell integrated control system is constructed. The fuel cell integrated control system includes a DC / DC controller power module, an air compressor controller power module, and a control system main control module. Among them, when the first switch on the DC / DC controller power module is switched to connect to the air compressor control circuit, and the second switch switches the grid interface in the voltage conversion circuit, the inductor in the voltage conversion circuit and the air compressor control circuit are connected to form a PFC circuit, and the grid interface is connected to the power battery interface. Through the formed PFC circuit, the control system main control module can keep the PFC circuit under constant voltage input by inputting a control signal to achieve the charging of the power battery. The embodiment of this application integrates the voltage conversion function of the DC / DC and the air compressor speed control function, and can realize the charging of the power battery in the fuel cell control system without additionally adding a PFC circuit module in the fuel cell control system, effectively reducing the problems of excessive cost, volume, and weight of the fuel cell control system.

[0077] The embodiment of this application also provides a fuel cell integrated control method, including the following steps executed in the fuel cell integrated control system:

[0078] The control system main control module obtains a charging instruction.

[0079] Among them, the charging instruction can be an instruction issued by the vehicle-mounted terminal, so that the vehicle switches from the discharging state of the fuel cell to the charging state of charging through the grid.

[0080] The DC / DC controller power module connects the air compressor control circuit and the inductor in the voltage conversion circuit according to the charging instruction.

[0081] The DC / DC controller power module connects the grid interface and the inductor in the voltage conversion circuit according to the charging instruction, and connects the power battery interface, so that the inductor in the voltage conversion circuit and the air compressor control circuit form a PFC circuit.

[0082] The control system main control module obtains the charging voltage.

[0083] The charging voltage is the voltage value required for the vehicle to charge, and a constant charging voltage is needed during the charging process.

[0084] The DC / DC controller power module and the air compressor controller power module output the charging voltage through the PFC circuit according to the charging voltage, where the fuel cell integrated control system is the fuel cell integrated control system mentioned in the above embodiments.

[0085] Further, the main control module of the control system includes a sampling circuit, a digital control unit, and a drive circuit.

[0086] Further, in the process where the DC / DC controller power module and the air compressor controller power module output the charging voltage through the PFC circuit according to the charging voltage, the specific steps are as follows:

[0087] The DC / DC controller power module and the air compressor controller power module obtain the voltage / current signals of the PFC circuit through the sampling circuit.

[0088] The digital control unit receives a control command, where the control command is sent by the host computer to the digital control unit according to the charging voltage and the voltage / current signals of the PFC circuit.

[0089] The digital control unit sends a control signal to the DC / DC controller power module and the air compressor controller power module through the drive circuit according to the received control command, so that the DC / DC controller power module and the air compressor controller power module output the charging voltage according to the control signal.

[0090] The sampling circuit is used for sampling the voltage / current signals. After sampling, the information is sent to the host computer for analysis. After analysis, the host computer sends a control command to the digital control unit. Finally, the digital control unit sends a control signal through the drive circuit to control the voltage of the PFC, so as to achieve the purpose of constantly outputting the charging voltage.

[0091] This application integrates the voltage conversion function of the DC / DC and the air compressor speed control function, and can realize the charging of the power battery in the fuel cell control system without adding an additional PFC circuit module in the fuel cell control system, which can effectively reduce the problems of excessive cost, volume, and weight of the fuel cell control system.

[0092] It should be understood that the solutions and products implemented based on the above fuel cell integrated control system should fall within the protection scope of this application.

[0093] Those skilled in the art can clearly understand that, for the convenience and conciseness of description, only the above-mentioned division of each functional unit and module is used as an example. In actual applications, the above functions can be assigned to different functional units and modules according to needs, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0094] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A fuel cell integrated control system, characterized in that, Comprising: A DC / DC controller power module, an air compressor controller power module, and a control system main control module; The DC / DC controller power module includes a voltage conversion circuit, a power grid interface, and a fuel cell interface. The voltage conversion circuit includes an inductor, a first switch, and a first switch tube. The first switch is used to switch the inductor to connect to the first switch tube or to connect to the air compressor control circuit. The DC / DC controller power module further includes a second switch, and the second switch is used to switch the voltage conversion circuit to connect to the fuel cell interface or to connect to the power grid interface; The air compressor controller power module includes the air compressor control circuit and a power battery interface. When the voltage conversion circuit is connected to the power grid interface and the first switch is switched to connect to the air compressor control circuit, the inductor in the voltage conversion circuit and the air compressor control circuit form a PFC circuit, and the power battery interface is connected, so that the fuel cell integrated control system can charge the power battery.

2. The control system according to claim 1, characterized in that, The first switch includes at least two switching connection ports. When the first switch is connected to the first switching connection port, the first switch connects the inductor and the first switch tube; when the first switch is connected to the second switching connection port, the first switch connects the inductor and the second switch tube.

3. The control system according to claim 1, characterized in that, The DC / DC controller power module adopts at least two parallel voltage conversion circuits, and the number of the first switches and the first switch tubes is the same as the number of the voltage conversion circuits.

4. The control system according to claim 1, characterized in that, The control system main control module includes a sampling circuit, a digital control unit, and a drive circuit; The sampling circuit is used to sample the voltage / current signals of the voltage conversion circuit and the air compressor control circuit; The digital control unit is used to receive the control commands issued by the upper computer and send control signals to the voltage conversion circuit and the air compressor control circuit through the drive circuit. The control signals include PWM signals and switch control signals.

5. The control system according to claim 4, characterized in that, When the voltage conversion circuit is connected to the fuel cell interface, the sampling circuit samples the voltage / current signals of the voltage conversion circuit and the air compressor control circuit; The digital control unit receives the target current signal, determines the control signal through the PI regulator, and makes the input current of the voltage conversion circuit equal to the target current by issuing the control signal; The digital control unit receives the target speed signal, determines the control signal through the PI regulator, and makes the air compressor speed reach the target speed by issuing the control signal.

6. The control system according to claim 4, characterized in that, When the voltage conversion circuit is connected to the power grid interface, the sampling circuit samples the voltage / current signals of the voltage conversion circuit and the air compressor control circuit; The digital control unit receives the target voltage signal, determines the control signal through the PI regulator, and makes the input voltage of the voltage conversion circuit equal to the target voltage by issuing the control signal.

7. The control system according to any one of claims 1 - 6, characterized in that, The first switch tube adopts a silicon carbide MOSFET switch tube.

8. The control system according to any one of claims 1 - 6, characterized in that, The power grid interface is a three-phase power grid interface.

9. A fuel cell integrated control method, characterized in that, Including the fuel cell integrated control system performing the following steps: The control system main control module obtains a charging instruction; The DC / DC controller power module turns on the inductor in the air compressor control circuit and the voltage conversion circuit according to the charging instruction; The DC / DC controller power module turns on the inductor in the grid interface and the voltage conversion circuit according to the charging instruction, and turns on the power battery interface, so that the inductor in the voltage conversion circuit and the air compressor control circuit form a PFC circuit; The main control module of the control system obtains the charging voltage; The DC / DC controller power module and the air compressor controller power module output the charging voltage through the PFC circuit according to the charging voltage, wherein the fuel cell integrated control system is the fuel cell integrated control system according to any one of claims 1-8.

10. The method according to claim 9, characterized in that, The main control module of the control system includes a sampling circuit, a digital control unit and a driving circuit. The DC / DC controller power module and the air compressor controller power module output the charging voltage through the PFC circuit according to the charging voltage, including: The DC / DC controller power module and the air compressor controller power module obtain the voltage / current signal of the PFC circuit through the sampling circuit; The digital control unit receives a control command, wherein the control command is sent by the host computer to the digital control unit according to the charging voltage and the voltage / current signal of the PFC circuit; The digital control unit sends a control signal to the DC / DC controller power module and the air compressor controller power module through the driving circuit according to the received control command, so that the DC / DC controller power module and the air compressor controller power module output the charging voltage according to the control signal.

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