CN100407484C - Fuel cell power generation system with operating parameter monitoring function - Google Patents

Abstract

The present invention provides a fuel cell power generation system with operation parameter monitoring function, which is characterized in that a set of operation parameter monitoring mechanism is set, which includes CAN bus, CAN interface single-chip microcomputer control board, liquid crystal display drive board and liquid crystal display screen, The input end of the CAN bus is connected to the selected sensors and monitors to receive the selected operating parameter data/signals and transmit them to the CAN interface single-chip microcomputer control board, and the CAN interface single-chip microcomputer control board collects the CAN interface data/signals and sends the data/ The signal format is converted and transmitted to the LCD driver board. The LCD driver board performs data/signal processing on various operating parameters, converts them and transmits them to the LCD screen to drive the LCD screen for correct display. The fuel cell power generation system with operation parameter monitoring function of the present invention can realize visual monitoring of various selected operation parameters, and can be conveniently used as a vehicle-mounted or ship-mounted power system, or as a movable power generation device.

Description

Fuel cell power generation system with operating parameter monitoring function

technical field

The invention relates to a fuel cell, in particular to a fuel cell power generation system with the function of monitoring operating parameters.

Background technique

A fuel cell is a device that converts the chemical energy generated during the electrochemical reaction of fuel and oxidant into electrical energy. The core component of the device is the membrane electrode (Membrane Electrode Assembly, referred to as MEA). The membrane electrode consists of a proton exchange membrane and two conductive porous diffusion materials (such as carbon paper) sandwiched on both sides of the membrane. A finely dispersed catalyst (such as metal platinum) that can initiate an electrochemical reaction is evenly distributed on the two boundary surfaces that are in contact with the conductive material. On both sides of the membrane electrode, the electrons generated during the electrochemical reaction are drawn out through the external circuit with conductive objects, forming a current loop.

At the anode end of the membrane electrode, the fuel can permeate through the porous diffusion material (such as carbon paper), and an electrochemical reaction occurs on the surface of the catalyst, losing electrons to form positive ions, which can migrate through the proton exchange membrane to reach The other end of the membrane electrode - the cathode end. At the cathode end of the membrane electrode, a gas (such as air) containing an oxidant (such as oxygen) penetrates through a porous diffusion material (such as carbon paper) and undergoes an electrochemical reaction on the surface of the catalyst to obtain electrons to form negative ions. It further combines with positive ions migrated from the anode end to form a reaction product.

In a proton exchange membrane fuel cell using hydrogen as fuel and oxygen-containing air as oxidant (or pure oxygen as oxidant), fuel hydrogen undergoes a catalytic electrochemical reaction in which electrons are lost in the anode region to form hydride ions (protons), Its electrochemical reaction equation is:

H ₂ →2H ⁺ +2e

Oxygen undergoes a catalytic electrochemical reaction in the cathode region to obtain electrons to form negative ions, which are further combined with hydrogen positive ions migrated from the anode terminal to form the reaction product water. Its electrochemical reaction equation is:

1/2O ₂ +2H ⁺ +2e→H ₂ O

The proton exchange membrane in the fuel cell is not only used for the electrochemical reaction and the protons generated in the transfer exchange reaction, but also to separate the gas flow containing fuel hydrogen from the gas flow containing oxidant (oxygen) so that they do not Will mix with each other to produce an explosive reaction.

In a typical proton exchange membrane fuel cell, the membrane electrode is generally placed between two conductive plates, and diversion grooves are opened on both plates, so it is also called a diversion plate. The diversion groove is opened on the surface in contact with the membrane electrode, formed by die-casting, stamping or mechanical milling, and its number is more than one. The guide plate can be made of metal material or graphite material. The function of the diversion groove on the diversion plate is to introduce fuel or oxidant into the anode area or cathode area on both sides of the membrane electrode respectively. In the structure of a single proton exchange membrane fuel cell, there is only one membrane electrode and two guide plates, and the two guide plates are arranged on both sides of the membrane electrode, one is used as the guide plate for the anode fuel, and the other As a guide plate for cathode oxidant. These two guide plates are not only used as current collector plates, but also as mechanical support on both sides of the membrane electrode. The diversion groove on the diversion plate is not only a channel for fuel or oxidant to enter the surface of the anode or cathode, but also a water outlet channel to take away the water generated during the operation of the battery.

In order to increase the power of a proton exchange membrane fuel cell, two or more single cells are usually connected together in a straight stacked or tiled manner to form a cell group, or called a cell stack. Such a battery pack is usually fastened together by a front end plate, a rear end plate and a pull rod to form a whole. In the battery pack, the two sides of the pole plate between the two proton exchange membranes are provided with diversion grooves, which are called bipolar plates. One side of the bipolar plate is used as the anode flow guide surface of one membrane electrode, and the other side is used as the cathode flow guide surface of another adjacent membrane electrode. A typical battery pack usually also includes: 1), inlets and diversion channels for fuel and oxidant gases. Its function is to evenly distribute fuel (such as hydrogen, methanol, or hydrogen-rich gas obtained by reforming methanol, natural gas, and gasoline) and oxidant (mainly oxygen or air) into the diversion grooves on each anode and cathode surface ; 2), the inlet, outlet and diversion channel of cooling fluid (such as water). Its function is to evenly distribute the cooling fluid to the cooling channels in each battery pack, absorb the reaction heat generated in the fuel cell and take it out of the battery pack for heat dissipation; 3), the outlet and guide channel of fuel and oxidant gas . Its function is to discharge the excess fuel gas and oxidant that did not participate in the reaction, and at the same time take out the liquid or gaseous water generated by the reaction. The above-mentioned fuel inlet and outlet, oxidant inlet and outlet and cooling fluid inlet and outlet are usually set on one end plate of the fuel cell stack or respectively set on two end plates.

Proton exchange membrane fuel cells can be used as power systems for vehicles, ships and other vehicles, and can also be made into mobile or fixed power generation systems.

A fuel cell power generation system generally consists of the following parts: fuel cell stack, fuel hydrogen supply subsystem, air supply subsystem, cooling and heat dissipation subsystem, automatic control subsystem and electric energy output subsystem.

Figure 1 is one of Shanghai Shenli Technology Co., Ltd. "A fuel cell with a dynamic control device" (invention patent application number: 200410016609.4, utility model patent application number: 200420020471.0), which is dynamically controlled by a fuel cell engine monitor Operating fuel cell power generation system. The fuel cell power generation system includes a fuel cell stack 1, a hydrogen cylinder 2, a pressure reducing valve 3, an air filter 4, an air compression supply device 5, a water-steam separator 6, a water tank 7, a water pump 8, a radiator 9, and a hydrogen circulation pump 10. A humidifier 11 with a rotary hydrogen path that can dynamically control the humidity, a humidifier 12 with a rotary air path that can dynamically control the humidity, a rotary humidifier with an adjustable speed motor 13, 13', and a hydrogen inlet pipeline Hydrogen relative humidity sensor 14, hydrogen temperature sensor 15 and pressure sensor 19, air relative humidity sensor 16, air temperature sensor 17 and pressure sensor 20 on the air inlet pipeline, cooling fluid temperature sensor 18 and pressure sensor on the cooling fluid inlet pipeline 21. A hydrogen temperature sensor 22 and a hydrogen pressure sensor 23 on the hydrogen outlet pipeline, a cooling fluid temperature sensor 24 and a cooling fluid pressure sensor 25 on the cooling fluid outlet pipeline, an air temperature sensor 26 and an air pressure sensor 27 on the air outlet pipeline, The working voltage of the fuel cell stack and the working voltage monitor 28 of each single cell, the working current monitor 29 of the fuel cell stack, the load automatic cut-off switch 30 , and the hydrogen automatic cut-off solenoid valve 31 .

The above-mentioned fuel cell power generation system follows the following principles and principles:

a. The allowable value of the output power of the fuel cell stack 1 is related to the rated operating temperature of the cooling fluid temperature sensor 18 on the cooling fluid inlet pipeline. Generally, a relationship between the allowable output value of the power and the value of the sensor 18 can be found. The closer the value of the sensor 18 is to The rated operating temperature, the larger the allowable output power or the closer to the rated output power;

b. The matching relationship between the output power of the fuel cell stack 1 and the fuel hydrogen flow rate and the air flow rate supplied to the fuel cell is calculated according to the hydrogen gas metering ratio of 1.2 and the air metering ratio of 2.0;

c. The hydrogen relative humidity sensor 14 and the air relative humidity sensor 16 are respectively related to the hydrogen temperature sensor 15, the air temperature sensor 17 and the pressure of hydrogen and air. It can be found that the gas flow reaches a certain relative pressure under certain pressure and temperature conditions. Generally speaking, the larger the gas flow, the higher the temperature and the lower the pressure, the harder it is to reach the high relative humidity value of the gas; on the contrary, the smaller the gas flow, the lower the temperature and the higher the pressure, the The gas is easier to reach the high relative humidity value of the gas;

d. The faster the rotation speed of the rotary humidifier, the higher the temperature and relative humidity of the hydrogen or air entering the fuel cell.

According to the operating principles or principles of the above-mentioned fuel cell power generation system, the control subsystem of the fuel cell power generation system is used to monitor and calculate the fuel cell operating temperature, output power requirements and the values of sensors 14, 15, 16, 17, and 18 to determine Set and control the rotation speed of the rotating motor of the rotary humidifier, and at the same time determine the control of the hydrogen flow and air flow, so that the fuel cell stack can achieve any power output requirements: 1. The relationship between output power and operating temperature Correlation control; 2. Correlation control of output power, hydrogen flow, and air flow (the hydrogen flow and air flow are measured according to the output power requirements of 1.2 and 2.0, respectively, to control the motor speed of the hydrogen circulation pump and the motor speed of the air pump); 3 .Hydrogen gas flow rate and air flow rate are respectively controlled in parallel with the corresponding motor speed in the humidification device that can realize dynamic humidification mediation control, so that the hydrogen gas and air entering the fuel cell stack at any flow rate can maintain the best relative humidity (a certain value in the middle of 70%～95%); 4. According to the situation of the outside weather temperature and humidity, the mediation and control method is the same as the 3rd point, and achieves the same purpose as the 3rd point. The ultimate goal is to enable the fuel cell stack to achieve high-efficiency operation and operate under the best working conditions under any power output requirements. The fuel cell stack can not only have the best fuel efficiency, but also greatly extend the working life.

Therefore, the control subsystem in the entire fuel cell engine or the entire power generation system is very important to realize the safe, high-efficiency and long-life operation of the fuel cell engine or power generation system.

In terms of safety assurance, it is mainly that when the control subsystem in the fuel cell engine or power generation system detects a certain working parameter, such as abnormal temperature, pressure, humidity, current, and voltage, it can alarm in time, and at the same time execute the self-control of the fuel cell engine. Protection, such as cut off load, cut off fuel hydrogen supply.

On the other hand, when the fuel cell power generation system is used as a function to test the performance of the fuel cell stack or to diagnose the operating conditions of the entire fuel cell power generation system, the control subsystem in the fuel cell power generation system must simultaneously monitor and display all operating parameters such as temperature , pressure, humidity, voltage, single cell voltage, etc. In order to optimize the operating conditions of the fuel cell stack or the entire fuel cell power generation system, the subsystems of the entire power generation system must be able to correct any temperature, pressure, humidity, current, and voltage during operation at any time.

At present, there are mainly two technologies for monitoring various working parameters of the fuel cell power generation system: one is when the fuel cell power generation system is used to test the performance of the fuel cell stack, or the entire power generation system of the fuel cell When diagnosing the operating conditions, the computer system is used for monitoring and control. For example: the patented technology of Shanghai Shenli Technology Company (China Patent No.: 200410017449.5) can monitor various operating parameters of the fuel cell power generation system such as temperature, pressure, humidity, voltage, voltage of each single cell, etc., and can monitor the operating conditions One of the parameters can be directly controlled and corrected. The other is that when the fuel cell power generation system is used as a vehicle power system or as a mobile power station, the monitoring and control are directly realized by the monitor.

The above two technologies for monitoring various operating parameters of the fuel cell power generation system have the following defects:

1. Use the computer system to monitor various parameters of the fuel cell power generation system such as: temperature, pressure, humidity, voltage, and the voltage of each single cell in the fuel cell. Although it is relatively intuitive, the computer system is often a relatively bulky device. When the power generation system is used as a vehicle-mounted or ship-borne power system or as a power generation device that is often moved, the fuel cell power generation system is required not only to be anti-vibration, but also to be simple and lightweight, and the computer system often cannot meet the requirements.

2. The monitor directly monitors various operating parameters of the fuel cell power generation system, such as temperature, pressure, humidity, voltage, and the voltage of each single cell in the fuel cell, which is not intuitive. The operator of the fuel cell power generation system cannot intuitively judge whether the system is in a normal state at any time. The monitor usually alarms and shuts down when a certain parameter in the operating parameters of the fuel cell power generation system reaches a dangerous limit. In this way, it is often impossible for the operating operator to know the abnormal process of the single fuel cell power generation system, and also loses the opportunity of human intervention to adjust the working parameters.

Contents of the invention

The object of the present invention is to provide a fuel cell power generation system with operating parameter monitoring function in order to solve the above problems, which can not only realize intuitive monitoring of selected operating parameters of the fuel cell power generation system, but also be conveniently used as a vehicle-mounted power generation system. , Shipboard power system, or used as mobile power generation equipment.

The object of the present invention is achieved in that a fuel cell power generation system with operating parameter monitoring function includes a fuel cell stack and an automatic control subsystem, and the automatic control subsystem includes a hydrogen relative humidity sensor arranged on the hydrogen inlet pipeline , temperature sensor and pressure sensor, air relative humidity sensor, temperature sensor and pressure sensor arranged on the air inlet pipeline, cooling fluid temperature sensor and pressure sensor arranged on the cooling fluid inlet pipeline, hydrogen temperature arranged on the hydrogen outlet pipeline Sensors and pressure sensors, the cooling fluid temperature sensor and pressure sensor arranged on the cooling fluid outlet pipeline, the air temperature sensor and pressure sensor arranged on the air outlet pipeline, and the fuel cell stack working voltage and the working voltage monitor of each single cell and a fuel cell stack operating current monitor; it is characterized in that: the automatic control subsystem also includes a set of operating parameter monitoring mechanism, which includes CAN bus, CAN interface microcontroller control board, liquid crystal display driver board and liquid crystal display The input end of the CAN bus is connected to the selected sensors and monitors to receive the selected operating parameter data/signals and transmit them to the CAN interface single-chip control board, and the CAN interface single-chip control board collects the CAN interface data/signals and The data/signal format is converted and transmitted to the LCD driver board. The LCD driver board performs data/signal processing on various operating parameters, converts them and transmits them to the LCD screen to drive the LCD screen for correct display.

Described CAN interface single-chip microcomputer control board mainly comprises single-chip microcomputer chip, CAN bus driver chip, CAN bus interface circuit and driver plate interface circuit, and its CAN bus interface circuit connects CAN bus and CAN bus driver chip, and the output of CAN bus driver chip connects single-chip computer chip, the output of the single-chip microcomputer chip is connected to the interface circuit of the driver board, and the output of the interface circuit of the driver board is connected to the input port of the liquid crystal display driver board.

The single-chip microcomputer chip is P87C591, and the CAN bus driver chip is 82C250.

The liquid crystal display driver board and liquid crystal display screen are general products.

The single-chip microcomputer chip is provided with system control software, selects the number, type and characteristics of the operating parameters of the fuel cell power generation system to be displayed, performs data analysis and format conversion, and sends them to the LCD driver board, and can correct deviations from the normal state The working parameters are color-coded.

Compared with the prior art, the fuel cell power generation system with operating parameter monitoring function of the present invention has the following advantages and positive effects due to the adoption of the above-mentioned technical solution:

1. The liquid crystal display in its operating parameter monitoring mechanism is a device that can be made very compact and can be customized according to the size and position of the man-machine interface. It is also relatively light in weight and anti-vibration, especially suitable for vehicles , Onboard, directly provide the driver with intuitive monitoring.

2. Since the designer can determine the display content of the display screen according to the needs, and can color-code display some working parameters that deviate from the normal state, it is convenient for the operator to effectively control the fuel cell power generation system, and can remind the operator in time to take Necessary control measures to ensure the safe operation of fuel cell power generation systems.

Description of drawings

The purpose, specific structural features and advantages of the present invention can be further understood through the following description of an embodiment of the fuel cell power generation system with operating parameter monitoring function of the present invention in conjunction with the accompanying drawings. Among them, the attached figure is:

Fig. 1 is a schematic diagram of the basic composition of a fuel cell with a dynamic control device in the prior art;

Fig. 2 is a functional block diagram of the operating parameter monitoring mechanism in the fuel cell power generation system with operating parameter monitoring function of the present invention;

Fig. 3 is the circuit schematic diagram of the CAN interface single-chip microcomputer control board among the present invention;

Fig. 4 is the software block diagram that the present invention compiles in the single-chip microcomputer of CAN interface single-chip microcomputer control board;

FIG. 5 is a diagram of a liquid crystal display interface according to an embodiment of the present invention.

Detailed ways

The fuel cell power generation system with operating parameter monitoring function of the present invention includes a fuel cell stack and an automatic control subsystem. The automatic control subsystem includes a hydrogen relative humidity sensor, a temperature sensor and a pressure sensor arranged on the hydrogen inlet pipeline, and is arranged on the air inlet. The air relative humidity sensor, temperature sensor and pressure sensor on the pipeline, the cooling fluid temperature sensor and pressure sensor on the cooling fluid inlet pipeline, the hydrogen temperature sensor and pressure sensor on the hydrogen outlet pipeline, and the cooling fluid outlet pipeline The cooling fluid temperature sensor and pressure sensor on the road, the air temperature sensor and pressure sensor arranged on the air outlet pipeline, and the fuel cell stack working voltage and the working voltage monitor of each single cell and the fuel cell stack working current monitor (the above The installation positions of sensors and monitors are shown in Figure 1). It also includes a set of operating parameter monitoring mechanism as shown in FIG. The input end of CAN bus 32 connects each selected sensor and monitor to receive selected work operation parameter data/signal and transmits it to CAN interface single-chip microcomputer control board 33, CAN interface single-chip microcomputer control board 33 gathers CAN interface data/signal and The data/signal format is converted and transmitted to the liquid crystal display driver board 34, and the liquid crystal display driver board 34 performs data/signal processing on various operating parameters, converts them and transmits them to the liquid crystal display screen 35 to drive the liquid crystal display screen to display correctly.

The liquid crystal display driver board 34 and the liquid crystal display screen 35 among the present invention adopt ready-made general-purpose products, and the CAN interface single-chip microcomputer control board 33 needs to design by oneself. Fig. 3 is a schematic circuit diagram of a CAN interface single-chip microcomputer control board designed by oneself in an embodiment of the present invention. CAN interface MCU control board mainly includes P87C591 MCU chip, 82C250 CAN bus driver chip, CAN bus interface circuit and driver board interface circuit. "D1" in the picture is P87C591 single-chip microcomputer chip, which is a single-chip microcomputer with internal CAN monitor compatible with 51 series produced by Philips. "N6" is 82C250 is CAN bus driver chip, CAN bus interface circuit is isolated by optocoupler "N3" and "N4", "N2" is the power supply of CAN bus interface circuit provided by DC/DC module. 7805 regulator chip "N1" provides 5V power supply. "J2" is the interface with the LCD driver board. "J12" is connected to 24v power supply. "J1" is the CAN bus interface. The CAN bus interface circuit is connected to the CAN bus and the CAN bus driver chip, the output of the CAN bus driver chip is connected to the single-chip microcomputer chip, the output of the single-chip microcomputer chip is connected to the driver board interface circuit, and the output of the driver board interface circuit is connected to the input port of the liquid crystal display driver board. The system control software is set in the single-chip microcomputer chip D1 to select the number, type and characteristics of the operating parameters of the fuel cell power generation system to be displayed, and to color-mark the operating parameters that deviate from the normal state. Fig. 4 is a software block diagram compiled in the single-chip microcomputer of the CAN interface single-chip microcomputer control board of the present invention. After the CAN interface microcontroller receives the CAN data, it analyzes the data, then converts the format, and finally sends the converted data to the LCD driver board for the next step of processing.

The fuel cell power generation system with operating parameter monitoring function of the present invention will be further described through a specific embodiment below.

A 10KW fuel cell power generation system is used as the power system of a fuel cell sightseeing car. The automatic control subsystem of the fuel cell tour bus adopts a set of operating parameter monitoring mechanism to control all states of the whole vehicle such as running, parking, and starting. The length of the liquid crystal display screen in this operating parameter monitoring mechanism is 27cm, width is 2.7cm, height is 19cm, and weight is 3 kilograms, is placed on the panel of tour bus driver and is convenient for driver to monitor directly.

In this embodiment, there is self-programmed software in the single-chip microcomputer control board of the CAN interface single-chip microcomputer, which determines the main operating parameters displayed on the display screen according to the number and characteristics of various parameters of the fuel cell power generation system, including fuel cell voltage and fuel cell current. , fuel cell stack water outlet temperature, air outlet temperature, hydrogen working pressure, hydrogen cylinder pressure, cooling water pressure and single cell working voltage, etc. After these working parameters are monitored by the sensors and monitors in the fuel cell generator system, after signal processing and transformation, they are transmitted to the CAN bus single-chip control board in the form of data, and then transmitted to the LCD driver board, which drives the LCD display. The displayed content is shown in Figure 5.

Claims (3)

1. fuel cell generation with operational factor function for monitoring, comprise fuel cell pack and autonomous control subsystem, described autonomous control subsystem comprises the hydrogen relative humidity sensor that is arranged on the hydrogen inlet pipeline, temperature sensor and pressure sensor, be arranged on the relative air humidity transducer on the air intlet pipeline, temperature sensor and pressure sensor, be arranged on cooling fluid temperature sensor and pressure sensor on the cooling fluid inlet ductwork, be arranged on hydrogen temperature transducer and pressure sensor on the hydrogen outlet pipeline, be arranged on cooling fluid temperature sensor and pressure sensor on the cooling fluid export pipeline, be arranged on air temperature sensor and pressure sensor on the air outlet slit pipeline, and the operating voltage watch-dog of fuel cell stack operation voltage and each monocell and fuel cell stack operation electric current monitor; It is characterized in that: described autonomous control subsystem also comprises a cover operational factor MA monitoring agency, this operational factor MA monitoring agency comprises the CAN bus, CAN interface singlechip control panel, liquid crystal display drive plate and LCDs, the input of CAN bus connects each selected transducer and watch-dog and receives selected work operational parameter data or signal and it is transferred to CAN interface singlechip control panel, CAN interface singlechip control panel is gathered CAN interface data or signal and data or signal format conversion is transferred to the liquid crystal display drive plate, and the liquid crystal display drive plate carries out data or signal processing to various work operational factors, being transferred to LCDs driving LCDs after the conversion correctly shows; Described CAN interface singlechip control panel mainly comprises singlechip chip, CAN bus driver chip, CAN bus interface circuit and drive plate interface circuit, its CAN bus interface circuit connects CAN bus and CAN bus driver chip, the output of CAN bus driver chip connects singlechip chip, the output of singlechip chip connects the drive plate interface circuit, and the output of drive plate interface circuit connects the input port of liquid crystal display drive plate.

2. the fuel cell generation with operational factor function for monitoring as claimed in claim 1 is characterized in that: described singlechip chip is P87C591, and described CAN bus driver chip is 82C250.

3. the fuel cell generation with operational factor function for monitoring as claimed in claim 1 or 2, it is characterized in that: be provided with system controlling software in the described singlechip chip, number, kind and the characteristics of the work operational factor of the fuel cell generation of selected required demonstration carry out data analysis and format conversion sends to the liquid crystal drive plate, and can mark look to the running parameter that departs from normal condition.

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