JPH03236165A - Control method for fuel cell power generating device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a fuel cell main body, a fuel processing device that supplies reformed fuel gas to a fuel electrode of the fuel cell main body,
an air supply device that supplies air to the air electrodes of the fuel cell; and an air supply device that supplies air to the air electrodes of the fuel cell;
Power conversion word that converts into the form according to the power! The present invention relates to a method for controlling a fuel cell generator comprising: and a control device for damping these devices.

[Conventional technology]

A block diagram of a conventional example of a fuel cell power generation device consisting of a fuel processing device, an air supply device, a fuel cell main body, a power conversion device, and a 111# device that drives these to HIGH is shown in the third example.
This power generation device shown in the figure consists of a fuel processing device 1 that reforms fossil fuel/hydrocarbon fuel into hydrogen-rich gas and supplies it to the fuel cell main body 3, and a fuel processing device 1 that reforms the fossil fuel/hydrocarbon fuel into hydrogen-rich gas and supplies it to the fuel cell main body 3.
an air supply device 2 that supplies air to the fuel cell, a fuel cell main body 3 that generates electricity through an electrochemical reaction between the fuel gas supplied by these devices and air, and a DC output from the fuel cell main body 3 that adapts to an external load. It is composed of a power conversion device 6 for converting power, and a control device 8 for controlling each of these devices. When operating such a fuel cell power generation device, the control device 8 performs load increase/decrease control in response to changes in load.

When the load increases, the power converter 6 can perform control in response to a load increase command from the load for a short period of milliseconds or less, but the output increase response of the fuel cell main body 3 is caused by the fuel processing device 1 and the air Generally, it is slow depending on the response speed of the supply device 2.

The response speed of the fuel processing bag f1 and the air supply device 2 to the load increase command is slower than that of the power conversion device because of the fuel processing bag! 1: The response process includes a chemical reaction such as an increase in the reforming amount (increase in the reforming reaction), and the re-equipment also includes the process of 'pIJ transfer', which is the movement of gas in the piping. is the cause.

[Problem to be Solved by the Invention] In such a fuel cell power generation device, when a load increase command from the load is input to the wI control device 8, this! The I+ control device 8 issues an output increase command to the power conversion device 6, a fuel gas amount increase command to the fuel processing device 1, and an air amount increase command to the air supply device 2. Moreover, these commands are issued instantaneously by setting the total value of the load amount, which is the previous load amount plus the new target value load amount to be increased, as the target setting value.

Therefore, as described above, the power conversion device 6 attempts to increase the output instantly without any time delay and requests an increase in the input from the fuel cell main body 3, but the fuel cell main body 3 Due to the time delay in the supply of fuel gas and air, the amount of power generation cannot be instantaneously increased, and the fuel cell main body 3 tries to increase the output current by force.
Scraping 1 of the fuel cell body 3 causes gas shortage, and as a result,
Among a large number of stacked cells, due to variations in the cross-sectional shape of the gas passages, the output voltage of the cells gradually decreases starting from the cell where gas does not flow easily, resulting in a "reversal phenomenon" of potential difference between the electrodes, and Due to the increase in the pressure difference between the gases, the ``atrium phenomenon'' occurs in which the fuel gas and air mix through the matrix, damaging the electrodes and other components of the fuel cell body 3 and disrupting the operation of the fuel cell. The problem was that it would become impossible to continue.

Figure 4 shows a time chart when such a phenomenon occurs; that is, at time A, a command to increase the load is issued instantaneously;
Power converter f6 will soon be ready to increase its output, but
The increase in the amount of reactant gas cannot keep up, and the output current of the fuel cell main body 3 increases only the current, but the voltage drops extremely,
The voltage detected by the voltage monitor 5 exceeds the voltage drop limit and the device trips at time B.

This invention has been made in view of the above points, and provides a fuel cell power generation device that controls the above-mentioned reversal phenomenon and blowout so that the phenomenon does not occur when a load increase command is issued to the fuel cell power generation device. The purpose is to provide a control method for

[Means to solve RIII]

In order to solve the above problems, the present invention includes a fuel cell main body, a fuel processing device that supplies reformed fuel gas to the fuel electrode of the fuel cell main body, and a fuel processing device that supplies air to the air electrode of the fuel cell. 1. Converting the electric power output from the air supply device and the fuel cell main body into a form according to the external load.
3. In a method for controlling a fuel cell power generation device comprising a power converter and a control device for controlling these devices, when the load suddenly increases, the amount of fuel gas supplied from the fuel processing device to the fuel cell main body and Until the amount of air supplied from the air supply device to the fuel cell main body reaches a value commensurate with the sudden increase in load, the output is suppressed wIm by the power conversion device while monitoring the output of the fuel cell main body.

[Operation] According to the present invention, when the load increases in the fuel cell power generation device, the control device detects the increased amount of fuel gas supplied from the fuel processing device and the increased amount of air supplied from the air supply device. At the same time, the output of the fuel cell itself is monitored, and the output of the power conversion device is controlled to be suppressed as appropriate until the amount of increase reaches a value commensurate with the target load increase value, thereby increasing the amount of power generated by the fuel cell itself. After the system is fully prepared, an output corresponding to the target increase value is supplied to the power converter.

〔Example〕

The present invention will be explained below based on examples. FIG. 1 is a block diagram showing an embodiment of the invention. In this figure, the fuel cell main body 13 is connected to the fuel processing device 11 and the air supply@! Fuel gas and air are supplied from 12. And the amount of fuel gas and air is controlled by a control device! It is input in F18. The output of the fuel cell main body 13 is emitted as an output by a voltmeter 15 and an ammeter 14, and is input to a meter control device 18 as monitoring power.

When a load increase command is input to the control bag 218, the power converter 16 receives the fuel gas amount and air amount mentioned above and the output monitoring input of the fuel cell main body 13, and increases the generated power tmt of the fuel cell main body. The output is controlled by constantly monitoring and receiving an appropriate output suppression control command from the control device 18.

FIG. 2 shows a time chart of each part when the control method according to the present invention is implemented when the load suddenly increases. Even if the target value for the sudden increase in load is set at time A, the control device 18 that has received this target value detects and monitors the reaction gas flow rate and the output of the fuel cell, and if this value is not sufficient, the control device The setting of the load increase target value outputted to the converter 16 is temporarily lowered to a low value, and the power converter 16 is operated. Until the point C when sufficient reaction gas corresponding to the load increase target value is supplied to the fuel cell main body 13 and the output current and voltage of the fuel cell main body reach the load increase target value,
The power conversion bag 216 is operated by the illilIwj device 18 while increasing and decreasing the setting of [1].

〔Effect of the invention〕

As mentioned above, this invention is a fully electric fuel cell! In , when the load suddenly increased, the output was controlled by suppressing the output of the power conversion device that supplies the load until the fuel cell itself was able to generate power commensurate with the increased load, so the power generation device could not be stopped. Not only can operation continue safely, but it can also prevent failures within the fuel cell itself due to reverse phenomena or blowout phenomena.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a fuel cell power generation system that implements the control method of this invention, Fig. 2 is a time chart when the load suddenly increases according to the control method of this invention, and Fig. 3 shows a case in which the conventional control method is implemented. FIG. 4, which is a block diagram showing the fuel cell power generation device, is a time chart when the load suddenly increases in the conventional method. 1.11: Fuel processing device, 2, 12: Air supply device, 3
, +3: fuel cell main body, 5.14.1s: fuel cell main body output monitoring, 6. +6: Power converter, 7.17: Negative 1st
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Claims (1)

[Claims] 1) A fuel cell main body, a fuel processing device that supplies reformed fuel gas to the fuel electrode of the fuel cell main body, an air supply device that supplies air to the air electrode of the fuel cell, and a fuel cell main body that supplies air to the fuel cell main body. In a method for controlling a fuel cell power generation device that includes a power conversion device that converts output power into a form that corresponds to an external load, and a control device that controls these devices, when the load suddenly increases, the fuel processing device Until the amount of fuel gas supplied to the fuel cell body and the amount of air supplied to the fuel cell body from the air supply device reach a value commensurate with the sudden increase in load, power conversion is performed while monitoring the output of the fuel cell body. 1. A method of controlling a fuel cell power generation device, characterized in that the device performs output suppression control.