Fuel cell power management and control system and method thereof

Abstract

The invention discloses a fuel cell power management and control system and a method thereof, and belongs to the technical field of fuel cell control and power electronics. The system comprises a main controller module, a power supply isolation and distribution module, a digital input / output isolation module, an analog quantity acquisition isolation module, a communication interface module and a load driving module. The power supply isolation and distribution module generates a + 24V power supply rail and a-24V power supply rail which are isolated from each other, and the + 24V power supply rail and the-24V power supply rail are respectively used for supplying power to a high-power load and an analog circuit to realize physical isolation of strong current and weak And each input / output and communication channel adopts an isolation design, so that electromagnetic interference is effectively inhibited. The control method comprises the steps of system initialization, multi-parameter acquisition, thermal management and power control based on a model, closed-loop communication and cooperative control, and graded fault diagnosis and protection. According to the invention, high integration, high reliability and intelligent management of fuel cell system control are realized, and the problems of system dispersion, high cost and poor anti-interference capability in the prior art are solved.

Description

Technical Field

[0001] This invention belongs to the field of fuel cell control and power electronics technology, specifically relating to a fuel cell power management and control system and its method. Background Technology

[0002] Fuel cell systems, as efficient and clean energy conversion devices, are widely used in new energy vehicles, distributed power generation, and other fields. A complete fuel cell system typically includes multiple subsystems such as a fuel cell stack, hydrogen supply system, air supply system, thermal management system, and power conversion and management unit. These subsystems require coordinated control by a high-performance, highly reliable electronic control system to ensure the safe, efficient, and stable operation of the entire system.

[0003] Currently, traditional fuel cell electronic control solutions often employ a distributed architecture, where functions such as stack control, auxiliary system control (e.g., fan, pump, heater), and power management of output power (e.g., DC-DC conversion, protection) are performed by multiple independent control units or hardware modules. For example, the electrical energy generated by the stack often requires a separate DC-DC converter for voltage conversion, current limiting, and overvoltage / overcurrent protection before it can be supplied to the load. This approach results in numerous system components, large size, and high cost. Furthermore, communication and coordination between units are complex, and signal transmission is susceptible to interference from high voltage, motor noise, and bus interference. It also makes it difficult to achieve rapid and accurate coordinated response between the stack's internal state and output power, thus hindering improvements in overall system performance and reliability. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a fuel cell power management and control system and method. Through high hardware integration and comprehensive signal isolation design, stack power management, auxiliary system control, and vehicle communication functions are integrated into a single electronic control unit, solving the problems of system dispersion, high cost, and poor anti-interference capability in existing technologies.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides a fuel cell power management and control system, comprising:

[0007] Main controller module: As the core control unit, it has a built-in microprocessor and core circuits such as system power supply, reset, clock, and data interface. It also integrates a multi-channel pulse width modulation (PWM) signal generator and is responsible for executing control algorithms, logic judgments, and task scheduling.

[0008] Power Supply and Distribution Module: This module is used to connect to an external battery or DC power supply and generates multiple stable-level power supplies through DC-DC isolated power supply technology. Crucially, it provides a +24V output and a +5V power rail. The +24V output is dedicated to powering high-power loads (such as heating elements and fan motors), while the +5V power rail provides a single power supply for analog circuits (such as operational amplifiers). Combined with a reference voltage bias network, this enables the operational amplifier to effectively acquire and amplify near-zero-level analog signals under single-supply conditions, improving system measurement accuracy.

[0009] Digital Input / Output Isolation Module: Connected to the main controller, it achieves electrical isolation through optocouplers or magnetic coupling devices; it includes multiple digital input channels for receiving switch status signals such as emergency stop buttons and hydrogen leak alarms; multiple digital output channels, at least one of which is a relay drive output for directly controlling the on / off state of high-current loads such as heating elements; and multiple PWM output channels for outputting isolated PWM signals to control fan speed, pump speed, etc.

[0010] Analog signal acquisition isolation module: includes multiple high-precision analog signal input channels for connecting pressure sensors, temperature sensors, etc.; after the sensor signals are processed by the isolation amplification circuit, they are sent to the analog-to-digital converter (ADC) port of the main controller to ensure that the accuracy of the acquired data is not affected by ground loop noise;

[0011] Communication interface module: Integrates at least one Controller Area Network (CAN) bus interface using an isolated CAN transceiver; this design ensures that common-mode noise and transient interference on the vehicle bus do not intrude into the control core, enabling stable and reliable data exchange with the vehicle controller (VCU), battery management system (BMS) or other devices;

[0012] Load drive module: directly powered by the isolated +24V power rail; this module includes fuel cell fan drive circuit, cooling fan drive circuit and heating element drive circuit, etc., and receives control signals from digital output isolation module or PWM isolation module to realize power drive and control of the corresponding load.

[0013] Secondly, the present invention provides a fuel cell control method applied to the above-mentioned system, comprising the following steps:

[0014] S1: System initialization and self-test; After power-on, the main controller initializes each peripheral module, reads the stored configuration parameters, and sequentially checks whether the power supply voltage, sensor communication, and output circuit are normal. After completing the self-test, it enters the ready state.

[0015] S2: Multi-parameter synchronous acquisition; periodically reads key parameters such as fuel cell inlet pressure, outlet pressure, coolant pressure, and temperature through the analog quantity acquisition isolation module; simultaneously reads switch status signals through the digital input channel;

[0016] S3: Model-based thermal management and power control; Based on the collected fuel cell stack temperature, output current and ambient temperature, the optimal PWM duty cycle of the fuel cell stack cooling fan and heat dissipation fan is dynamically calculated using preset fuzzy control or PID and other advanced control algorithms, and precise control is implemented through the PWM output channel to maintain the fuel cell stack operating temperature within the optimal range; In the event of system cold start or low temperature environment, the heating element is controlled to work through relay output to create suitable operating temperature conditions for the fuel cell stack;

[0017] S4: Closed-loop communication and collaborative control; Through an isolated CAN bus interface, system status data (voltage, current, temperature, pressure, fault codes) is uploaded to the vehicle network in real time, and power demand commands and start / stop commands are received from the upper-level controller (such as VCU); Based on the received power demand and its own current status, the system dynamically adjusts the speed of the air supply system (which can be controlled by reserved PWM or analog output) to achieve rapid power following response;

[0018] S5: Hierarchical fault diagnosis and protection; real-time judgment of whether all collected data and status exceed preset safety thresholds; early warning and log recording for general anomalies; immediate triggering of protection procedures for serious faults (such as sudden drop in hydrogen pressure, stack overheating, output short circuit, etc.), including shutting down the hydrogen supply solenoid valve, disconnecting the main relay, stopping all fans and heating elements, and sending the highest priority emergency fault message through the CAN bus, forming a multi-layered safety protection system combining hardware and software.

[0019] Compared with the prior art, the present invention provides a fuel cell power management and control system and method, which has the following beneficial effects:

[0020] 1. This invention, through comprehensive design including power isolation, digital I / O isolation, analog signal acquisition isolation, and communication interface isolation, fundamentally solves the problem of damage to the core control circuit of the fuel cell system caused by high voltage, motor noise, and bus interference, and greatly improves the long-term operational stability and reliability of the system in complex electromagnetic environments.

[0021] 2. This invention integrates high-precision analog signal acquisition and multi-channel PWM output, combined with advanced control algorithms, to achieve precise closed-loop control of key parameters such as stack temperature and reactant gas pressure, thereby optimizing the stack operating point, improving power generation efficiency and extending stack lifespan.

[0022] 3. This invention highly integrates power management, signal conditioning, load driving, and communication interfaces into a single electronic control unit (such as a single PCB), which significantly reduces the number of external wiring, connectors, and independent components, thereby reducing the overall system cost, size, and failure rate.

[0023] 4. The modular hardware design and rich configurable I / O interfaces (digital I / O, PWM, analog input, CAN) of this invention enable the electronic control system to be flexibly adapted to fuel cell systems of different power levels from kilowatts to hundreds of kilowatts through software configuration, making it highly versatile.

[0024] 5. This invention designs a complete fault diagnosis and protection chain from signal acquisition and logic judgment to actuator linkage, and can be linked with the vehicle safety network through an isolated CAN bus to form a multi-layered safety protection system that combines proactive early warning and rapid protection. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0026] Figure 1 This is a schematic diagram of the hardware architecture and interface of a fuel cell power management and control system according to an embodiment of the present invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] like Figure 1 As shown, the fuel cell power management and control system of this embodiment is designed as a highly integrated printed circuit board (PCB); its external interface is brought out through standard connectors and is mainly divided into the following areas:

[0029] Control and Communication Interface Area: Provides the minimum system interface for the main controller, including signal ground (SVGND), serial communication pins (TX, RX), clock (CLK), data (DAT), reset (RES), and 3.3V core power supply; it also has an isolated CAN bus interface (CAN1) for connecting to the vehicle CAN network; the "lock line positive" and "lock line negative" interfaces are used to receive vehicle wake-up or safety interlock signals;

[0030] Digital and PWM Input / Output Area: Includes opto-isolated digital input channels IN2 and IN3, which can be configured to detect start button, high voltage interlock status, or alarm signals; includes opto-isolated PWM output channels PWM1 and PWM2, whose outputs can control the fan speed controller after passing through the drive circuit; and also includes a relay drive output R, which integrates a drive transistor and a freewheeling diode for direct control of the heating element relay coil.

[0031] Power and Analog Input Area: "Battery+" and "Battery-" are the system's main power input terminals, accepting a wide voltage input of 18-36VDC; the internal power isolation and distribution module generates mutually isolated +24V, -24V, and 3.3V power supplies; among them, +24V powers all fans and relays; -24V provides negative power to the operational amplifier in the analog acquisition isolation module; PT1, PT2, PT3, and PT4 are four isolated analog voltage input channels, respectively connected to the fuel cell stack hydrogen inlet pressure sensor, outlet pressure sensor, coolant inlet pressure sensor, and fuel cell stack temperature sensor (the temperature sensor signal is converted into a voltage signal by a transmitter); GND is the signal reference ground for these sensors, achieving precise single-point grounding within the board;

[0032] High-power load connection area: The "heating element" terminal is connected to the contact controlled by the relay output R; the "fuel stack fan" and "heat sink fan" terminals are respectively connected to the power MOSFET drive circuit controlled by PWM1 and PWM2 signals, and are directly powered by +24V power supply.

[0033] The system workflow is as follows:

[0034] 1. Connect “Battery+” and “Battery-” to power on the system; the power isolation and distribution module works to generate isolated power supplies; the main controller MCU starts up, executes the initialization program, and after completing the self-test, sends a network online message through CAN1.

[0035] 2. The system enters the main loop, and the MCU polls and executes tasks at fixed intervals (e.g., 10ms):

[0036] a. Data acquisition task: Read the switch status of IN2 and IN3; sequentially sample the voltage values ​​of PT1-PT4 channels through the ADC, and convert them into actual pressure and temperature values ​​according to the sensor calibration curve;

[0037] b. Control Calculation Task: Based on the collected fuel cell stack temperature and pressure data, and the VCU power demand command (such as the demand current value) received from the CAN bus, the fuzzy-PID composite control algorithm stored in the FLASH is invoked; the algorithm calculates the optimal heat dissipation capacity required at present, and then solves the duty cycle of PWM1 (controlling the fuel cell stack fan) and PWM2 (controlling the cooling fan); if the fuel cell stack temperature is lower than the minimum start-up temperature, R is set to high level to start the heating element;

[0038] c. Communication task: Pack the system status (voltage, current, temperature, pressure, operating mode) into periodic CAN messages (e.g., sent once every 100ms) and broadcast them to the bus; at the same time, parse the received CAN commands, such as new power settings or emergency stop commands;

[0039] d. Fault monitoring task: Real-time verification of all parameters; for example, if the PT1 (hydrogen inlet pressure) value is lower than the minimum safety threshold for more than 200ms, it is determined as a "serious hydrogen supply failure"; the MCU immediately executes the protection procedure: pulls the R signal low to shut down the heating; sets PWM1 and PWM2 to 100% duty cycle, making the fan run at full speed to assist in heat dissipation; sends the highest priority "emergency stop request" message to the VCU through CAN1 and records the fault code;

[0040] 3. The system continues to run until it receives a normal shutdown command from the VCU or triggers an unrecoverable critical fault protection. When shutting down, it safely shuts down each load in sequence and finally enters a low-power sleep mode.

[0041] Example 1: Power Management and Control System Applied to Hydrogen Fuel Cell Bus

[0042] This embodiment describes an integrated electronic control unit (ECU) for a hydrogen fuel cell bus. The core of the system is a highly integrated PCB, model SZQT-FCU500V1.1. Externally, it connects to the vehicle's 18-36V DC power supply via "battery+" and "battery-" terminals. The internal power isolation and distribution module employs DC-DC isolation technology to generate electrically isolated +24V and -24V power rails. The +24V rail is dedicated to powering high-power load drive circuits, while the -24V rail provides negative power to analog circuits, isolating strong electrical noise at its source.

[0043] The main controller uses a 32-bit microprocessor and integrates an ADC and a PWM generator. During the initialization phase, the controller completes the configuration of each module and power and communication self-tests, and then sends an online message through the isolated CAN interface.

[0044] The system operates in 10ms cycles. Within each cycle, the switch status is first read through two optocoupler-isolated digital input channels (IN2, IN3), and the hydrogen inlet / outlet pressure, coolant pressure, and fuel cell stack temperature signals are acquired through four isolated analog input channels (PT1-PT4). These analog signals are all isolated and amplified before being sent to the ADC.

[0045] The control algorithm employs a fuzzy-PID composite strategy. Based on the collected temperature, pressure, and VCU power commands received from the CAN bus, it calculates the heat dissipation power required to maintain the optimal temperature of the fuel cell stack, and determines the PWM duty cycle for the fuel cell stack fan (PWM1 control) and the cooling fan (PWM2 control). If the fuel cell stack temperature is too low, the heating element is activated by driving the relay output R.

[0046] In terms of communication, the system packages status data into periodic CAN messages for broadcast and parses VCU commands in real time. Fault monitoring is continuous. For example, if the hydrogen inlet pressure (PT1) remains too low, a serious fault is determined, and the protection program is immediately executed: the heater is shut down (pulling R low), the fan runs at full speed (PWM duty cycle 100%), and a highest priority emergency shutdown message is sent via CAN, while the fault code is recorded.

[0047] Example 2: Fuel Cell Power Management Unit for Distributed Generation or Backup Power Supply

[0048] This embodiment is designed for industrial backup power supply scenarios, featuring a wall-mounted independent electrical control box. Its core motherboard supports a wide voltage DC input range of 12-48V, and the power module uses a high-efficiency isolated DC-DC converter to generate +24V and -24V power, and can also generate other auxiliary power supplies.

[0049] The main controller is an industrial-grade processor. The digital I / O isolation module expands the number of channels, providing more digital inputs to connect to sensors such as smoke and water immersion sensors, as well as multiple digital outputs. The analog acquisition isolation module has been increased to 8 channels, supporting the acquisition of signals such as ambient temperature and humidity, bus voltage and current, and hydrogen concentration, and is compatible with 4-20mA current loop input.

[0050] The communication interface module integrates two isolated CAN buses, one for communication with the upper-level energy management system and the other for collaboration with internal subsystems (such as the hydrogen controller). It can also provide an RS-485 interface for connecting to the local HMI.

[0051] The load drive utilizes an intelligent power module with protection features. The control algorithm is more advanced, incorporating environmental parameters and load prediction for thermal management. The system possesses autonomous operating logic, intelligently managing power output and start / stop in both grid-connected and off-grid modes.

[0052] Fault diagnosis establishes a multi-parameter correlation model, which not only monitors single-point data but also performs cross-validation (such as correlating differential pressure with current to determine blockage). Protection actions include mitigation strategies such as graded load reduction to maintain power supply continuity. All operational data is stored with timestamps for easy maintenance and analysis.

[0053] Example 3: Rugged control system for special vehicles or construction machinery

[0054] This embodiment addresses the high vibration and wide temperature range requirements of special vehicles by comprehensively ruggedizing the hardware. The electronic control unit is encapsulated in a metal casing, the main PCB is a six-layer board, and the connectors use military-grade or automotive-grade sealing components. The power supply front end is equipped with robust protection circuitry to ensure stable operation under severe voltage fluctuations.

[0055] The main controller uses automotive-grade chips that meet functional safety standards. Digital I / O employs high-speed isolation devices to reduce signal delay, and digital inputs feature built-in intelligent debouncing filtering. The analog signal acquisition circuitry has added shielding and integrates a vibration sensor interface.

[0056] The communication module integrates a multi-channel isolated CANFD interface to meet high-speed data exchange requirements, enabling low-latency communication with the powertrain controller, body network, and other components. The load drive module monitors fan current to detect stall, and the heating drive can be finely adjusted using PWM solid-state devices.

[0057] The system is optimized for dynamic operating conditions, with a shorter data acquisition cycle (e.g., 5ms). The control algorithm incorporates a feedforward loop, which can adjust the air compressor speed and cooling strategy in advance based on predicted changes in power demand. Fault diagnosis follows functional safety principles, with the highest-level fault triggering "fail-safe" protection and alarming through redundant communication paths. The system may also have a "limp-home" degraded operation capability.

[0058] Example 4: Cost-Optimized Control Unit for Commercial Vehicles

[0059] This embodiment targets the commercial vehicle market, optimizing costs while maintaining core advantages. The system is designed as a standardized, pluggable module, using cost-effective industrial-grade components. The power module employs a mature dual-output isolation scheme, with basic protection on the input side.

[0060] The main controller uses a commercially available, mature vehicle-grade microprocessor. The number of digital I / O channels is moderate, meeting basic functional requirements (e.g., 4 digital inputs, 4 digital outputs, and 2 PWM outputs). Analog input is configured with 6 standard inputs, covering core fuel cell stack parameters and total output voltage and current.

[0061] The communication interface strictly adheres to vehicle platform specifications, integrating one isolated CAN 2.0B interface with a fixed speed and good compatibility. UART may be retained for easy diagnostics. The load drive design is simple and robust; the fan drive uses an integrated protection MOSFET, and the heating drive uses a high-margin relay.

[0062] The control algorithm employs robust PID control combined with feedforward compensation, and parameters can be calibrated via CAN. For the recurring operating conditions of commercial vehicles, the algorithm can incorporate learning capabilities based on historical data to optimize energy efficiency. Fault diagnosis is clearly categorized into three levels: information, warning, and fault, with explicit protection actions. The system prioritizes maintainability, supporting detailed data reading via CAN for rapid diagnosis and modular replacement.

[0063] Example 5: Intelligent Experimental Platform for Cutting-Edge Research

[0064] This embodiment is a highly integrated, high-configuration research platform. Its PCB adopts high-density interconnect technology, with highly integrated functions, and can even include a low-power DC-DC converter. The power module provides multiple precise, low-noise isolated power supplies with flexible input methods.

[0065] The main controller employs a high-performance processor, boasting powerful computing capabilities and abundant peripherals. It offers a sufficient number of digital I / O and analog acquisition channels, with the latter supporting up to 24 channels of high-resolution synchronous sampling, compatible with various sensor types, and featuring a high sampling rate.

[0066] The communication interfaces are extremely rich, including multi-channel CANFD, Ethernet, wireless modules, and serial ports, facilitating integration into various experimental networks. The load drive module is flexible and can include a programmable current source to drive precision actuators.

[0067] The system workflow is highly configurable, allowing users to define the functions and algorithms of each channel via a host computer. Based on a real-time operating system, tasks can run in parallel across multiple cycles. It offers deep data acquisition, supporting the simultaneous acquisition of research data such as single-cell voltage. The control algorithm can be adjusted online, facilitating the verification of new strategies. Fault diagnosis, protection thresholds, and actions are fully customizable, and it supports data-driven fault prediction and health management functions, making it a powerful integrated platform for scientific research control and analysis.

[0068] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fuel cell power management and control system, characterized in that, include: The main controller module has a built-in microprocessor and integrates a multi-channel PWM signal generator; Power supply and distribution module: used to connect to an external battery or DC power supply, and generate multiple stable power levels through DC-DC isolated power supply technology; Crucially, the module provides a +24V output and a +5V power rail; the +24V output is dedicated to powering high-power loads; the +5V power rail provides a single power supply for analog circuits, which, together with the reference voltage bias network, enables the operational amplifier to effectively acquire and amplify near-zero level analog signals under single power supply conditions, thereby improving the system's measurement accuracy. A digital input / output isolation module, connected to the main controller module, includes multiple isolated digital input channels, multiple isolated digital output channels, and multiple isolated PWM output channels; An analog signal acquisition isolation module, connected to the main controller module, includes multiple isolated analog signal input channels for connecting sensors; The communication interface module integrates at least one isolated controller area network (CAN) bus interface; The load drive module is powered by the +24V power rail and receives control signals from the digital input / output isolation module to drive the fuel cell stack fan, cooling fan and heating element load.

2. The fuel cell power management and control system according to claim 1, characterized in that, The +24V power rail generated by the power isolation and distribution module is dedicated to powering the high-power load in the load drive module, and the -24V power rail is dedicated to powering the analog circuits in the analog acquisition isolation module.

3. The fuel cell power management and control system according to claim 1, characterized in that, At least one digital output channel in the digital input / output isolation module is a relay drive output channel, used to directly control the on / off state of the heating element load.

4. The fuel cell power management and control system according to claim 1, characterized in that, The analog signal input channel of the analog acquisition isolation module is used to acquire the inlet pressure, outlet pressure, coolant pressure, and temperature signals of the fuel cell stack.

5. A fuel cell power management and control system according to claim 1, characterized in that, The communication interface module exchanges data with the vehicle controller (VCU) or battery management system (BMS) through the isolated CAN bus interface.

6. A control method for a fuel cell power management and control system according to any one of claims 1-5, characterized in that, Includes the following steps: Step S1, System Initialization and Self-Test: After power-on, the main controller initializes each module and performs status checks; Step S2, Multi-parameter synchronous acquisition: Periodically acquire sensor data and switch status; Step S3: Model-based thermal management and power control: Based on the stack temperature, output current and ambient temperature, dynamically calculate and output PWM control signals for the stack fan and cooling fan, and control the heating element to work according to temperature requirements. Step S4, Closed-loop communication and coordinated control: Send and receive system status data and power demand commands via CAN bus, and adjust the system output power according to the commands; Step S5, Graded Fault Diagnosis and Protection: Monitor system parameters in real time and execute early warning or protection actions according to the level of abnormality.

7. The control method for a fuel cell power management and control system according to claim 6, characterized in that, In step S3, the optimal PWM duty cycle of the fan is calculated using fuzzy control or PID control algorithms.

8. The control method for a fuel cell power management and control system according to claim 6, characterized in that, Step S4 specifically includes: receiving a power demand command from the upper-level controller, and, in conjunction with the current system status, adjusting the rotation speed of the air supply system to achieve power following.

9. The control method for a fuel cell power management and control system according to claim 6, characterized in that, In step S5, for serious faults, a protection procedure is executed that includes shutting off the hydrogen supply, disconnecting the main relay, stopping the fan and heating element drive, and sending the highest priority fault message via the CAN bus.

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