TWI674207B - Fuel cell protection method - Google Patents

Abstract

A protection method for a fuel cell is suitable for being installed on a load, and the load is electrically connected to the fuel cell and a secondary battery, respectively. The method includes the following steps. First, when the humidity of the fuel cell is less than the air humidity, or The voltage value corresponding to the non-output power is lower than the set value, a regulating device disconnects the fuel cell output power to the load, and outputs it from the secondary battery, and activates the fuel cell until the humidity of the fuel cell is greater than or equal to The air humidity, or the voltage value corresponding to the non-output power, is greater than or equal to the set value. The activation includes that the current or power of the fuel cell operated by the control device increases in a trapezoidal square wave with time. Finally, the control device disconnects the two The secondary battery instead outputs power from the fuel cell to the load.

Description

Protection method of fuel cell

The invention relates to a protection method, in particular to a protection method for a fuel cell.

Fuel cells have the advantages of low pollution, high efficiency, and high energy density, so they have become the object of research and development and promotion in various countries in recent years. Among various fuel cells, the proton exchange membrane fuel cell (PEMFC) has the lowest industrial temperature because of its low operating temperature, rapid start-up, and high energy density in volume and weight.

If the fuel cell is not used for a long time during each start-up, the environmental humidity of its membrane electrode group will become worse. Therefore, the activation process of the fuel cell must be used to wet the membrane electrode group and stimulate its electrochemical reaction. The fuel cell can enter the normal electrochemical reaction efficiency to reach the rated output power. To test various characteristics of the fuel cell (such as current-voltage characteristics), these parameters must be set under controllable conditions, and appropriate testing and sampling methods must be set according to the characteristics of the fuel cell to obtain the most accurate signals. Capture and test results.

At present, the fuel cell test is performed by connecting the fuel cell with an electronic load machine as the power consumption to achieve the activation purpose. However, before the actual test, technicians need to spend a lot of time in the pipeline between related components. The connection and connection of the circuit and the use of electronic loaders as power consumption are a waste of power generated by electronic loaders. In addition, due to the large size and high cost of electronic loaders, electronic loaders are used as fuel cells The test will be detrimental to the commercial promotion and practical application of fuel cells.

The above-mentioned shortcomings show various problems arising from the use of conventional fuel cells. If the existing activation methods can be improved, a simplified activation operation schedule can be designed, and at the same time, the requirements of environmental protection and energy saving can be improved, the industrial applicability will be improved.

In view of this, an object of the present invention is to provide a method for protecting a fuel cell, which is suitable for being mounted on a load, and the load is electrically connected to the fuel cell and a secondary battery, respectively, and includes the following steps.

First, when the humidity of the fuel cell is lower than the humidity of the air, or the voltage value corresponding to the non-output power is lower than a set value, a regulating device disconnects the output power of the fuel cell to the load and outputs it from the secondary battery instead, and Activate the fuel cell until the humidity of the fuel cell is greater than or equal to the humidity of the air, or the voltage value corresponding to the non-output power is greater than or equal to a set value. The activation includes the regulation device operating the fuel cell current or power in a trapezoidal shape with time. The square wave increases. Finally, the regulating device disconnects the secondary battery and changes the output power of the fuel cell to the load.

Another technical means of the present invention is that the above-mentioned regulating device disconnects the output power of the secondary battery to the load, and the power generated by the operation of the load is converted into power and transmitted to the secondary battery to charge it.

Another technical means of the present invention is that the above-mentioned regulating device disconnects the output power of the fuel cell to the load, the power required for the fuel cell to activate, and the power supply transformed by the power generated by the operation of the load.

Another technical means of the present invention is that the above-mentioned control device sets the time length and the value of the current or power for activation.

Another technical means of the present invention is that the above-mentioned trapezoidal square wave is composed of a continuous complex square wave.

Another technical means of the present invention lies in the combustion described above. During the time that the battery is activated, the time of each square wave is the same.

Another technical means of the present invention is that the current or power of each square wave is the same during the activation time of the above fuel cell.

Another technical means of the present invention is that the aforementioned load is an electric mobile vehicle.

Another technical means of the present invention is that when the humidity of the fuel cell is 5% lower than the humidity of the air or the voltage value corresponding to the non-output power is lower than 90% of the set value, the regulating device activates the fuel cell.

The beneficial effect of the present invention is that the fuel cell is activated by the regulating device during the running of the vehicle, and the secondary battery outputs power to the vehicle to make the vehicle run uninterrupted, which is different from the conventional use of an electronic loader. As the demand for power consumption, an external power source is required to consume energy. In addition to converting the power generated by the vehicle during the driving process into electricity for the fuel cell to activate, the vehicle's motor requires more practical power. In order to achieve the unexpected benefits of energy conservation.

1‧‧‧ fuel cell

2‧‧‧ secondary battery

3‧‧‧ load

31‧‧‧Motor

4‧‧‧Regulator

91 ~ 93‧‧‧step

FIG. 1 is a schematic block diagram illustrating a preferred embodiment of a protection method for a fuel cell according to the present invention; FIG. 2 is a step diagram illustrating a schematic flowchart of the preferred embodiment; FIG. 3 is a schematic diagram illustrating the preferred implementation In the example, the power and time of the fuel cell are trapezoidally rising and the square wave is activated and pulled; FIG. 4 is a schematic diagram illustrating the square wave of power and time of the fuel cell being trapezoidally rising in the preferred embodiment. Another aspect of the activated load; and FIG. 5 is a schematic diagram illustrating the power consumption of the fuel cell in combination with a load in the preferred embodiment.

Features and patents of related patent applications related to the present invention It will be clearly shown in the following detailed description of the preferred embodiment with reference to the accompanying drawings.

Referring to FIGS. 1 and 2, a protection method for a fuel cell according to the present invention is suitable for being mounted on a load 3, wherein the load 3 is an electric mobile vehicle, and the load 3 is respectively connected with the fuel cells 1 and 12 The secondary battery 2 is electrically connected. Here, the fuel cell 1 and the secondary battery 2 can be separately powered to operate the motor 31 of the vehicle, which includes the following steps.

First, step 91 is performed. When the humidity of the fuel cell 1 is less than the humidity of the air, or the voltage value corresponding to the output power is lower than the set value, a regulating device 4 disconnects the output power of the fuel cell 1 to the load 3, and changes The secondary battery 2 outputs power to the load 3, and activates the fuel cell 1 until the humidity of the fuel cell 1 is greater than or equal to the air humidity, or the voltage value corresponding to the non-output power is greater than or equal to a set value, wherein, the Activation includes that the current or power of the fuel cell 1 is increased by a trapezoidal square wave with time, that is, the fuel cell 1 is controlled to not increase with the load 3, but gradually increase with the trapezoidal square wave until it returns to The maximum value of the fuel cell 1.

The conditions for activating the fuel cell 1 are one of the following: 1. When the humidity of the fuel cell 1 is less than the humidity of the air; 2. The voltage value corresponding to the non-output power is lower than the set value. Further, the condition for stopping the activation of the fuel cell 1 is one of the following: 1. The humidity of the fuel cell 1 is greater than the humidity of the air; 2. The humidity of the fuel cell 1 is equal to the humidity of the air; 3. The voltage corresponding to the non-output power The value is greater than the set value; 4. The voltage value corresponding to the non-output power is equal to the set value.

When the regulating device 4 disconnects the output power of the fuel cell 1 to the load 3, the power required for the fuel cell 1 to be activated, and the power supply converted by the power generated by the operation of the load 3.

According to the present invention, the fuel cell 1 is activated by the regulating device 4 during the driving process of the vehicle to simplify the activation time course, which is different from the conventional method. Knowing the false consumption requirements of using the electronic load machine as power, external power is needed to consume energy and the equipment is expensive. In addition to converting the power generated by the motor 31 during the driving process into electricity for the activation of the fuel cell 1, the motor 31 Drive more realistic power requirements to achieve unexpected benefits in energy savings.

The fuel cell 1 generates water during operation and does not need to be activated. On the contrary, if it has not been used for a long time, it must pass through the activation process to wet the membrane electrode group of the fuel cell 1 and stimulate its electrochemical reaction. When the humidity of the fuel cell 1 is 5% lower than the humidity of the air, or the voltage value corresponding to the output power is lower than 90% of the set value, the regulating device 4 activates the fuel cell 1 to a healthy state to avoid The fuel cell 1 is damaged due to too low humidity during startup. In actual implementation, a hygrometer (not shown) can be set to detect the humidity and voltmeter to test the voltage value.

By using the control device 4 to control the secondary battery 2 to output power to the vehicle to actuate the motor 31, in addition to making the vehicle uninterrupted during the driving process, the dual purpose of activating the fuel cell 1 is also achieved during the driving process. In particular, after the fuel cell 1 is activated, if it does not return to the maximum value of the fuel cell 1, the activation is performed again until it returns to the maximum value of the fuel cell 1.

The control device 4 can set a time length and a current or power value for activating the fuel cell 1. Since the current or power, activation time, maximum value, activation square wave size, number of square waves, and square wave slope of the fuel cell 1 depend on the development agreement or requirements of each brand, Designed to meet the activation and loading of fuel cells 1 of different brands.

With reference to Figures 3 and 4, it is assumed that the square wave of the power of the fuel cell 1 rises gradually in a trapezoidal shape over time. It can be seen from the figure that the activation load of the fuel cell 1 of different manufacturers will have a square wave according to the factory specifications. oblique Rate, square wave number, square wave size, activation time, power and other differences. For example, if 10kw of power is pulled within 60 seconds (sec), the time of each load during activation is 5sec, and the power is 10 / 12kw. The power and time mentioned here are only examples. This is limited.

Referring to FIG. 5 again, the fuel cell 1 is pulled in a trapezoidal square wave and matched with the power consumption of the load 3. Among them, the FC power is the fuel cell 1, the lithium battery power is the secondary battery 2, and the total output power is The load 3. During the activation process, the fuel cell 1 does not generate power according to the load 3's demand, but gradually increases with the trapezoidal rising square wave until it returns to the maximum value of the fuel cell 1.

Further, the trapezoidal square wave is composed of a continuous complex square wave. During the activation time, each square wave has the same time, and during the activation time, each square wave has the same current or power.

Among them, the power of each square wave is △ P, and the time of each square wave is △ t, , The range of A is between ~ between. In addition, when the current of each square wave is △ A and the time of each square wave is △ t, , And A and B are certain values.

Next, step 92 is performed. The control device 4 disconnects the secondary battery 2 and outputs power from the fuel cell 1 to the load 3.

Finally, step 93 is performed, and the power generated by the operation of the load 3 is converted into electric power and transmitted to the secondary battery 2 to charge the secondary battery 2.

The fuel cell 1 or the secondary battery 2 is switched by the regulating device 4 to power the motor 31 to make the vehicle run uninterrupted, and at the same time, the fuel cell 1 is activated during the driving process without the need for expensive and bulky laboratories. In addition to simplifying the activation time and cost of the electronic loader, it is more beneficial to the commercial application of the fuel cell 1 and further The power generated by the vehicle during the driving process is converted into electric power, and the electric power is provided to the fuel cell 1 or the secondary battery 2 to achieve the environmental protection benefit of saving energy.

In summary, according to the fuel cell protection method of the present invention, the load 3 is electrically connected to the fuel cell 1 and the secondary battery 2 respectively, and the fuel cell 1 is activated by the regulating device 4 during the driving of the vehicle. It is different from the conventional consumption demand of using an electronic load machine as power. It requires an external power source to consume energy and expensive equipment. In addition to converting the power generated by the motor 31 during driving into electricity for the activation of the fuel cell 1 In addition, the motor 31 of the vehicle travels with more practical power requirements to achieve the unexpected benefits of energy conservation, so it can indeed achieve the purpose of cost invention.

However, the above are only the preferred embodiments of the present invention. When the scope of implementation of the present invention cannot be limited by this, that is, the simple equivalent changes and modifications made according to the scope of the patent application and the description of the invention, All are still within the scope of the invention patent.

Claims (10)

A protection method for a fuel cell is suitable for being installed on a load, and the load is electrically connected to the fuel cell and a secondary battery, respectively. The method includes the following steps: When the humidity of the fuel cell is less than the air humidity, a regulating device Disconnect the fuel cell output power to the load, and output it from the secondary battery, and activate the fuel cell until the humidity of the fuel cell is greater than or equal to the humidity of the air. The activation includes the control device to actuate the power of the fuel cell with Time increases in a trapezoidal square wave; and the regulating device disconnects the secondary battery and outputs power from the fuel cell to the load. According to the fuel cell protection method described in item 1 of the scope of the patent application, the method further includes: when the voltage value corresponding to the non-output power of the fuel cell is lower than a set value, the regulating device disconnects the output power of the fuel cell to the load, and Instead, it is output by the secondary battery, and the fuel cell is activated until the voltage value corresponding to the fuel cell's non-output power is greater than or equal to a set value. The activation includes that the regulating device operates the fuel cell with a trapezoidal square wave over time. increase. According to the method for protecting a fuel cell according to item 2 of the scope of patent application, wherein when the regulating device disconnects the output power of the secondary battery to the load, The power generated by the operation of the load is converted into electricity and transmitted to the secondary battery to charge it. The protection method for a fuel cell according to item 3 of the scope of the patent application, wherein when the control device disconnects the fuel cell output power to the load, the power required for the fuel cell to activate is the power generated by the load operation And change the power supply. The protection method for a fuel cell according to item 4 of the scope of the patent application, wherein the control device sets a time length and a current or power value for activation. The method for protecting a fuel cell according to item 5 of the scope of the patent application, wherein the trapezoidal square wave is composed of a continuous complex square wave. According to the method for protecting a fuel cell according to item 6 of the scope of the patent application, the time of each square wave is the same during the activation time. According to the fuel cell protection method according to item 7 of the scope of the patent application, in the time of activation, the current or power of each square wave is the same. The method for protecting a fuel cell according to item 8 of the scope of the patent application, wherein the load is an electric mobile vehicle. According to the fuel cell protection method described in item 2 of the scope of the patent application, when the humidity of the fuel cell is lower than 5% of the humidity of the air, or the voltage value corresponding to the non-output power is lower than 90% of the set value, the regulation The device activates the fuel cell.