JPH10112328A - Fuel cell generating set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the installation space of a discharge device to reduce cost. SOLUTION: A DC voltage adjusting device 2 and a power inverter 3 are connected to the output of a fuel cell main unit 1, and a discharge resistance 4 is connected to the output side of the DC voltage adjusting device 2 through a switch 8. In normal operation, fuel cell voltage 5 is inputted as a detecting value to a control device 9 for controlling output voltage 7 of the DC voltage adjusting device 2 by using command in operation as an command value, and in discharge, the fuel cell voltage 5 is controlled by using command in discharge as an command value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell power generator for obtaining electric energy by an electrochemical reaction, and more particularly to a fuel cell power generator having a discharge device for safely releasing energy when a power generation operation is stopped.

[0002]

2. Description of the Related Art In a fuel cell power generation system in which a fuel gas containing hydrogen is supplied to a fuel electrode and an oxidizing gas containing oxygen is supplied to an oxidizing electrode, electric energy is obtained by an electrochemical reaction. When the power supply operation is stopped by shutting off the supply, the supply of the fuel gas and the oxidizing gas is also stopped. However, these reaction gases remain in the fuel cell main body, and power generation is continued by the residual gases. Therefore, the method of discharging the electric energy of the power generation by the residual gas by the discharge device is adopted.However, the generated voltage may damage the catalyst of each electrode, or the electrode may be corroded by an excessive discharge current. In order to avoid this, it is necessary to control the output voltage of the fuel cell body within a predetermined range.

FIG. 3 is a schematic diagram showing a basic configuration example of a conventional discharge device of a fuel cell power generator. Fuel cell body 1
And a DC voltage regulator 2 that receives the DC output of the fuel cell body 1 and adjusts the voltage, and an inverter 3 that receives the DC output of the DC voltage regulator 2 and converts it into AC power. A discharge control device 6 and a discharge resistor 4 are provided on the output side of the fuel cell body 1, and the discharge current flowing through the discharge resistor 4 is controlled using the discharge control device 6 at the time of discharging. Is controlled to fall within a predetermined range.

[0004]

As described above, in the conventional fuel cell power generator, the exclusive discharge control device 6 is incorporated to control the discharge current, thereby preventing the fuel cell body 1 from being damaged at the time of discharge. ing. However, with such a configuration, the incorporation of the dedicated discharge control device 6 becomes an essential condition, and the required installation space becomes large,
In addition, there is a disadvantage that the cost is high. In particular, in a fuel cell power generator having a large output capacity, the required capacity of the discharge device is also large, so a larger installation space is required,
In addition, the cost will further increase.

An object of the present invention is to provide a fuel cell power generator which requires a small installation space for the discharge device and is inexpensive.

[0006]

In order to achieve the above object, the present invention provides: (1) a fuel cell body, a DC voltage adjusting device for adjusting a voltage by receiving a DC output of the fuel cell body, An inverter that receives the DC output of the regulator and converts it to AC power, and a discharge resistor connected to the output side of the DC voltage regulator via a switch, and further, when receiving an operation command, the DC voltage Outputs a control signal to the DC voltage regulator so that the output voltage of the regulator becomes the set value, and outputs a control signal to the DC voltage regulator so that the output voltage of the fuel cell main unit becomes the set value when a discharge command is received. A fuel cell power generation device is provided with a control device that performs the control.

(2) A fuel cell body, an inverter for converting the DC output of the fuel cell body into AC power, and a discharge resistor connected to the output side of the inverter via a switch. Further, a control signal is output to the inverter when the operation command is received, so that the output voltage of the inverter is set to the set value, and the output voltage of the fuel cell body is set to the set value when the discharge command is received. Thus, a fuel cell power generator is provided with a control device that outputs a control signal to the inverter.

According to the above (1), a function of adjusting the output voltage of the fuel cell main body at the time of discharging is added to the control device used for adjusting the output voltage of the DC voltage adjusting device during operation. Therefore, there is no need to incorporate a dedicated discharge control device as in the related art, and the required installation space for incorporating the discharge device is small, and the required cost is reduced. Further, if the above (2) is satisfied, similarly, the control device used for adjusting the output voltage of the inverting device during operation includes:
Since the function of adjusting the output voltage of the fuel cell main body at the time of discharging is added, there is no need to install a dedicated discharge control device, the installation space required for assembling the discharge device is small, and the cost is reduced.

[0009]

FIG. 1 is a schematic diagram showing a basic configuration of a discharge device according to a first embodiment of a fuel cell power generator according to the present invention. In the present embodiment, the DC voltage regulator 2 and the inverter 3 are connected to the output of the fuel cell main body 1, and the discharge resistor 4 is connected to the output side of the DC voltage regulator 2 via the switch 8. Further, the fuel cell voltage 5 input to the DC voltage regulator 2 and the output voltage 7 on the output side of the DC voltage regulator 2 are input to the control device 9 that controls the DC voltage regulator 2 as detection values. During normal operation, the output voltage 7 is controlled using the operation time command as a command value. When the operation is stopped and discharge is performed, the output is adjusted to control the fuel cell voltage 5 using the discharge time command as the command value. Is performed.

In this configuration, the function of adjusting the fuel cell voltage 5 at the time of discharge is added to the control device 9, so that it is necessary to provide a dedicated discharge control device as used in the conventional configuration. There is no. Therefore, the required installation space for the discharge device can be reduced, and the required cost can be reduced.
FIG. 2 is a schematic diagram showing a basic configuration of a discharge device according to a second embodiment of the fuel cell power generator according to the present invention.

In the present embodiment, an inverter 3A is connected to the output of the fuel cell body 1, and a discharge resistor 4A is connected to the output side of the inverter 3A via a switch 8A. Also,
The fuel cell voltage 5 input to the inverter 3A and the output voltage 10 on the output side of the inverter 3A are input to the control device 9A that controls the inverter 3A as detection values. At the time of normal operation, the operation time command is set as the command value and the output voltage 10
When the operation is stopped and discharge is performed, the output is adjusted so that the fuel cell voltage 5 is controlled using the discharge time command as a command value.

Also in this configuration, since the function of adjusting the fuel cell voltage 5 at the time of discharge is added to the control device 9A, there is no need to provide a dedicated discharge control device, and the required installation space of the discharge device is reduced. It is smaller and costs are lower. In addition, as the discharge resistor 4A used in this configuration,
If an auxiliary heater used in the operation of the fuel cell power generator, for example, a heater incorporated in a steam separator of a cooling water system, is used, there is no need to provide a discharge resistor dedicated for discharge, so that a required installation space is reduced. It will be smaller and the cost will be lower.

[0013]

As described above, according to the present invention, since the fuel cell power generator is configured as described in claim 1 or 2, there is no need to provide a dedicated discharge control device. The required installation space for the discharge device is small, and a fuel cell power generator with a low required cost can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a basic configuration of a discharge device according to a first embodiment of a fuel cell power generator according to the present invention.

FIG. 2 is a schematic diagram showing a basic configuration of a discharge device according to a second embodiment of the fuel cell power generator according to the present invention.

FIG. 3 is a schematic diagram showing an example of a basic configuration of a discharge device of a conventional fuel cell power generator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel cell main body 2 DC voltage regulator 3 Inverter 3A Inverter 4 Discharge resistance 4A Discharge resistance 5 Fuel cell voltage 7 Output voltage 8 Switch 8A Switch 9 Control device 9A Control device 10 Output voltage

Claims (2)

[Claims] 1. A fuel cell main body, a DC voltage adjusting device that receives a DC output of the fuel cell main body and adjusts a voltage, an inverting device that receives a DC output of the DC voltage adjusting device and converts the DC output into AC power, and a switch. A discharge resistor connected to the output side of the DC voltage regulator via the DC voltage regulator, and further outputs a control signal to the DC voltage regulator so that the output voltage of the DC voltage regulator becomes a set value when an operation command is received. A fuel cell power generator, comprising: a controller that outputs a control signal to a DC voltage regulator so that an output voltage of a fuel cell main body becomes a set value when a discharge command is received. 2. A fuel cell main body, an inverter for receiving DC output of the fuel cell main body and converting the DC output into AC power, and a discharge resistor connected to an output side of the inverter via a switch. A control signal is output to the inverter to set the output voltage of the inverter to a set value when an operation command is received, and an inverse conversion is performed to set the output voltage of the fuel cell body to a set value when a discharge command is received. A fuel cell power generator comprising a control device for outputting a control signal to the device.