KR20120080018A - An electric generating system using a fuel cell - Google Patents

Abstract

PURPOSE: A power generation system is provided to raise a load-driving performance, thereby capable of preventing damages to fuel cell, and to maximize energy recycle efficiency. CONSTITUTION: A power generation system(100) using a fuel cell comprises: a fuel cell stack(20) generating DC power; a conversion unit converting the DC power to AC power; a secondary power consumption unit(60) calculating a secondary power by comparing a first power and a second power, and transferring a third power which is subtracted from the second power by the secondary power to an instantaneous power compensation unit; a battery management unit(70) charging a battery by using a compensation power; and the instantaneous power compensation unit(80) supplying the third power to a load(300), supplying second power to the load in case the second power is same with the first power, and supplying the second power to the load after compensating the second power in case the second power is lower than the first power.

Description

Power plant using fuel cell {AN ELECTRIC GENERATING SYSTEM USING A FUEL CELL}

The present invention relates to a power generation system using a fuel cell for directly converting chemical energy into electrical energy.

As fossil fuels are depleted and global warming becomes a real issue, interest in sustainable and environmentally friendly energy sources is increasing. The devices have been developed accordingly, including solar power generators using solar energy, wind power generators using wind, and fuel cells that produce electricity and heat by chemical reaction between hydrogen and oxygen. Here, power generation using a fuel cell is environmentally friendly, compared to photovoltaic power generation or wind power generation, there is an advantage capable of continuously generating power regardless of environmental conditions.

Recently, emergency power generation systems using molten carbonate fuel cells (MCFCs) have been used for commercial power generation and are operating in conjunction with power systems.

The power generation system using such a fuel cell is used for electricity production that supplies electricity to the load together with the power system in normal times when there is no problem with the power system, and operates in an independent operation mode in case of an emergency in which the power system has a problem. Although it can be used for the electrostatic countermeasure for supplying electricity, since the fuel cell generates power in a mechanical process and a chemical process, there is a characteristic that the load tracking performance is low because the response for the change of the output is not fast.

That is, there is no problem when a power generation system using a fuel cell is connected to a power system to supply power to a load jointly, but when used as an emergency power supply device, power cannot be supplied normally due to low load following performance. A problem arises.

For example, if the output of the fuel cell is 2000Kw and the power demand of the load is 1500Kw or the instantaneous demand power is 2100Kw, the output of the fuel cell should be changed to 1500Kw or 2100Kw. There is a problem that it is difficult to convert the output of the battery in real time according to the required power of the load.

As a result, in a conventional power generation system using a fuel cell, when operating in the independent operation mode, when the output of the fuel cell is higher than the output of the load (distorted output current due to the load characteristics) or the instantaneous load exceeding the output of the fuel cell Is generated, there is a problem of reducing the power supply stability of the fuel cell and shortening the life of the fuel cell.

In order to solve the problems of the prior art as described above, the present invention monitors the fluctuations of the output of the fuel cell and the output of the load in real time in the independent operation mode to adjust the output of the fuel cell to respond quickly to the output fluctuation of the load To provide a power generation system using a fuel cell.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention which are not mentioned can be understood by the following description, and will be more clearly understood by the embodiments of the present invention. It will also be readily apparent that the objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

An apparatus of the present invention for achieving the above object is a power generation system using a fuel cell operating in an independent operation mode, the fuel cell stack for producing a direct current power; Conversion means for converting the DC power produced by the fuel cell stack into AC power; After calculating the surplus power by comparing the power required by the load (hereinafter referred to as the first power) with the AC power converted by the conversion means (hereinafter referred to as the second power), a predetermined power (hereinafter referred to as compensation power) is calculated from the surplus power. Is transferred to the battery management means and consumes the remaining power (hereinafter referred to as power consumption), and transfers the third power obtained by subtracting the surplus power from the second power to the instantaneous power compensation means, wherein the second power is the first power. Surplus power consumption means for transferring the second power to the instantaneous power compensation means when less than or equal to; Battery management means for charging the battery using the compensation power received from the surplus power consumption means; And supplying the load to the load when the third power is received, and supplying the second power to the load if the second power is the same as the first power when the second power is received and less than the first power. And the instantaneous power compensation means for supplying the load after compensating the second power in cooperation with the battery management means.

In addition, the present invention can be converted to an uninterrupted mode by supplying instantaneous power to the load during the time when the fuel cell and the load is momentarily shut off when switching from the normal operation mode to the independent operation mode.

The present invention as described above, by monitoring the output of the fuel cell and the output fluctuation of the load in real time operation mode in real time to adjust the output of the fuel cell to quickly respond to the output fluctuation of the load, it is possible to increase the load following performance It works.

That is, the present invention detects the output of the fuel cell and the output of the load in real time in the independent operation mode in real time, when the power demand of the load is lower than the output of the fuel cell forcibly consume surplus power, the power demand of the load is fuel When higher than the output of the battery by using the pre-stored surplus power to compensate the output of the fuel cell, it is possible to increase the load tracking performance to prevent damage to the fuel cell.

In addition, the present invention has the effect of maximizing energy recycling efficiency by enabling the use of heat energy generated in the process of consuming surplus power, such as heating, power generation.

1 is a configuration diagram of an embodiment of a power generation system 100 using a fuel cell according to the present invention;
2 is a diagram illustrating an embodiment of an MBOP 10 of a power generation system using a fuel cell according to the present invention;
3 is a diagram illustrating an embodiment of an EBOP 30 of a power generation system using a fuel cell according to the present invention;
4 is a configuration diagram of an embodiment of a monitoring unit 40 of a power generation system using a fuel cell according to the present invention;
5 is a configuration diagram of an embodiment of a surplus power consumption module 60 of a power generation system using a fuel cell according to the present invention;
6 is a configuration diagram of an embodiment of a battery management module 70 of a power generation system using a fuel cell according to the present invention;
7 is an exemplary view illustrating an operating state of a power generation system using a fuel cell according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings, It can be easily carried out. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a configuration diagram of an embodiment of a power generation system using a fuel cell according to the present invention.

As shown in FIG. 1, the power generation system 100 using a fuel cell according to the present invention includes a mechanical balance of plant (MBOP) 10, a fuel cell stack 20, and an electrical balance. Of Plant (30), the monitoring unit 40, switch 50, surplus power consumption module 60, battery management module 70, and instantaneous power compensation module 80.

The MBOP 10 supplies oxygen and hydrogen to the fuel cell stack 20.

The fuel cell stack 20 electrochemically reacts oxygen and hydrogen supplied from the MBOP 10 to produce direct current power.

The EBOP 30 converts the DC power produced by the fuel cell stack 20 into AC power that can be used in the load 300, and then converts the converted AC power through the power system 200 and the load through the switch 50. Transfer to 300 or surplus power consumption module 60.

When the power generation system 100 operates in the independent operation mode (hereinafter, in the independent operation mode), the surplus power consumption module 60 may set the power required by the load 300 (hereinafter, referred to as the first power) at a predetermined time interval. And compares the first power and the power output from the fuel cell stack 20 and received through the EBOP 30 and the switch 50 (hereinafter, referred to as a second power). 1 power), and the predetermined power (hereinafter, referred to as compensation power) is transferred to the battery management module 70 from the calculated surplus power, and the remaining power (hereinafter, referred to as power consumption) is consumed. In this case, the first power is equal to the value obtained by subtracting the surplus power from the second power, and the surplus power is equal to the sum of the compensation power and the power consumption. Here, the compensation power is preferably less than 90% of the surplus power.

In addition, the surplus power consumption module 60 transmits the third power obtained by subtracting the surplus power from the second power to the instantaneous power compensation module 80 and notifies the fact to the instantaneous power compensation module 80.

The battery management module 70 then charges the battery 72 using the compensation power received from the surplus power consumption module 60.

In addition, when the second power is less than the first power, the surplus power consumption module 60 transmits the second power to the instantaneous power compensation module 80 and notifies the fact to the instantaneous power compensation module 80.

Then, the instantaneous power compensation module 80 supplies the third power received from the surplus power consumption module 60 to the load 300.

In addition, the instantaneous power compensation module 80 is supplied to the load 300 as it is, if the second power received from the surplus power consumption module 60 is the same as the first power, if the first power is less than the battery management module 70 The second power is compensated to be the same as the first power by interlocking with and supplied to the load 300.

Hereinafter, each component of the power generation system 100 using a fuel cell according to the present invention will be described in more detail with reference to FIGS. 2 to 6.

-Configuration of MBOP 10-

As shown in FIG. 2, the MBOP 10 includes an oxygen supply unit 12 and a fuel gas supply unit 14.

The oxygen supply unit 12 supplies oxygen to the fuel cell stack 20.

The fuel gas supply unit 14 supplies fuel gas (eg, hydrogen) to the fuel cell stack 20. Details of these configurations have already been implemented in various forms, and detailed descriptions thereof will be omitted.

-Composition of Fuel Cell Stack 20-

The fuel cell stack 20 electrochemically reacts oxygen and hydrogen supplied from the MBOP 10 to produce direct current power. The principle of the electrochemical reaction between oxygen and hydrogen in the fuel cell stack 20 is as follows. First, the hydrogen supplied to the fuel electrode (anode) is separated into hydrogen ions and electrons, the hydrogen ions move through the electrolyte layer to the air pole, and the electrons move to the air pole through the external circuit. Oxygen ions and hydrogen ions meet at the cathode (electrode) to generate electricity (low voltage DC power), water, and heat.

-Configuration of EBOP 30-

As shown in FIG. 3, the EBOP 30 includes a DC-DC converter 32 and a DC-AC converter 34.

The DC-DC converter 32 converts the low voltage direct current power produced by the fuel cell stack 20 into a predetermined level of direct current power.

The DC-AC converter 34 converts the DC power converted to a predetermined level into AC power for use in the power system 200 and the load 300.

-Configuration of the monitoring unit 40-

As shown in FIG. 4, the monitoring unit 40 includes a monitoring unit 42 and a breaker 44.

The monitor 42 monitors whether the power system 200 is broken at predetermined time intervals.

The breaker 44 controls the switch 50 to connect the output terminal of the EBOP 30 with the load 300 and the power system 200 when a failure does not occur in the power system 200 (in the normal operation mode). The second power is supplied to both the load 300 and the power system 200.

In addition, the breaker 44 controls the switch 50 to connect the output terminal of the EBOP 30 and the surplus power consumption module 60 when a failure occurs in the power system 200 (when the independent operation mode). At this time, the breaker 44 controls the switch 50 to cut off the electrical connection between the power system 200 and the load 300.

Configuration of Switch 50

The switch 50 supplies the AC power supplied from the DC-AC converter 34 of the EBOP 30 to the power system 200 and the load 300 in the normal operation mode according to the monitoring result of the monitoring unit 60. do.

In addition, the switch 50 supplies the AC power supplied from the DC-AC converter 34 of the EBOP 30 to the surplus power consumption module 60 in the independent operation mode according to the monitoring result of the monitoring unit 60. .

-Configuration of surplus power consumption module 60-

As shown in FIG. 5, the surplus power consumption module 60 includes a first detector 62, a second detector 64, a controller 66, and a resistance load 68.

The first detector 62 measures the first power in real time.

The second detector 64 measures the second power in real time.

The controller 66 calculates surplus power by comparing the first power sensed by the first detector 62 and the second power sensed by the second detector 64, and then calculates the surplus power from the calculated surplus power. Compensation power) is transferred to the battery management module 70, and the remaining power (power consumption) is transferred to the resistance load 68. At this time, the third power is obtained by subtracting the surplus power from the second power to the instantaneous power compensation module 80.

For example, assuming that the second power is 2000Kw and the first power is 1000Kw, the surplus power is 1000Kw, and the compensation power is set to 90% of the surplus power (designer can set arbitrarily). And power consumption is 100 Kw.

In addition, when the second power is less than or equal to the first power, the controller 66 transmits the second power to the instantaneous power compensation module 80.

As a result, when the second power exceeds the first power, the controller 66 transfers the compensation power to the battery management module 70, transfers the power consumption to the resistance load 68, and transfers the third power to the instantaneous power compensation module. When the second power does not exceed the first power, the second power is transferred to the instantaneous power compensation module 80.

The resistance load 68 converts power consumption received from the controller 66 into thermal energy. The thermal energy by the surplus power is recovered through a separate thermal energy recovery device, or converted and stored in the form of electromagnetic energy through a capacitor, a superconducting coil, or converted into chemical energy through a storage battery, or stored in mechanical energy through a flywheel. Can be converted to and stored.

-Configuration of Battery Management Module 70-

As shown in FIG. 6, the battery management module 70 includes a battery 72 and a power supply 74.

The battery 72 stores the compensation power supplied from the surplus power consumption module 60.

The power supply unit 74 converts the DC power output from the battery 72 into AC power and supplies the DC power to the instantaneous power compensation module 80.

Here, the battery management module 70 further includes an AC-DC converter (not shown) which converts the compensating power of AC into DC power and transfers the same to the battery 72.

-Configuration of instantaneous power compensation module 80-

The instantaneous power compensation module 80 supplies the second power to the load 300 when receiving the third power from the surplus power consumption module 60.

In addition, the instantaneous power compensation module 80 supplies the second power to the load 300 when the second power received from the surplus power consumption module 60 is the same as the first power.

In addition, when the second power received from the surplus power consumption module 60 is less than the first power, the instantaneous power compensation module 80 interoperates with the battery management module 70 to compensate for the second power corresponding to the first power. After the load 300 is supplied.

7 is an exemplary view illustrating an operating state of a power generation system using a fuel cell according to the present invention.

As shown in FIG. 7, the fuel cell stack 20 always outputs 100% of power regardless of whether the power system 200 is abnormal.

At this time, in the state in which the power system 200 is normal, the fuel cell stack 20 supplies 100% of the power output to the load 300 and the power system 200, but if an abnormality occurs in the power system 200, the fuel The battery EBOP 30 and the load 300 are disconnected, and the surplus power consumption module 60 or the instantaneous power compensation module 80 immediately adjusts the power to the load 300 in the same manner as described above. ).

That is, the present invention adjusts the second power to supply the load 300 to match the first power required by the load 300 when an abnormality occurs in the power system 200, thereby preventing damage to the fuel cell.

Thereafter, when the power system 200 is normalized, power (100%) output from the fuel cell stack 20 is supplied to the load 300 and the power system 200 as it is.

As a result, the fuel cell stack 20 outputs 100% of power regardless of whether the power system 200 is abnormal, and 100% of power output from the fuel cell stack 20 is normal when the power system 200 is normal. This is not a problem, but it causes a problem when the power system is abnormal.

Therefore, when an abnormality occurs in the power system, the second power is adjusted to match the first power required by the load 300, thereby preventing damage to the fuel cell stack 20 as well as the load 300.

Hereinafter, an operation process of a power generation system using a fuel cell according to the present invention will be described.

First, the fuel cell stack 20 receives oxygen and hydrogen from the MBOP 10 to produce an electrochemical reaction to produce DC power.

Thereafter, the EBOP 30 converts the DC power produced by the fuel cell stack 20 into AC power that can be used in the load 300.

Thereafter, when the monitoring unit 40 detects a failure of the power system 200, the controller 40 switches to the independent operation mode, controls the switch 50, and receives the AC power supplied from the DC-AC converter 34 of the EBOP 30. Second power) is supplied to the surplus power consumption module 60.

Then, the surplus power consumption module 60 determines the first power required by the load 300 at a predetermined time interval, calculates surplus power by comparing the identified first power and the second power, and calculates the surplus power from the calculated surplus power. The predetermined power (compensation power) is transmitted to the battery management module 70, and the remaining power (power consumption) is consumed through the resistance load 68.

The battery management module 70 then charges the battery 72 using the compensation power received from the surplus power consumption module 60.

In addition, the surplus power consumption module 60 transmits the third power obtained by subtracting the surplus power from the second power to the instantaneous power compensation module 80 and notifies the fact to the instantaneous power compensation module 80.

In addition, when the second power is less than the first power, the surplus power consumption module 60 transmits the second power to the instantaneous power compensation module 80 and informs the fact to the instantaneous power compensation module 80.

Then, the instantaneous power compensation module 80 receives the third power from the surplus power consumption module 60 and supplies it to the load 300.

The instantaneous power compensation module 80 supplies the second power to the load 300 when the second power received from the surplus power consumption module 60 is equal to the first power.

When the second power is less than the first power, the instantaneous power compensation module 80 compensates for the second power to be the same as the first power in cooperation with the battery management module 70 and supplies the load 300 to the load 300.

In the present invention, the meaning of the same includes not only the case of exactly the same but also the case within a predetermined range.

Meanwhile, the method of the present invention as described above can be written in a computer program. And the code and code segments constituting the program can be easily deduced by a computer programmer in the field. In addition, the written program is stored in a computer-readable recording medium (information storage medium), and read and executed by a computer to implement the method of the present invention. The recording medium may include any type of computer readable recording medium.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. The present invention is not limited to the drawings.

10: MBOP 20: fuel cell stack
30: EBOP 40: monitoring unit
50: switch 60: surplus power consumption module
70: battery management module 80: instantaneous power compensation module

Claims (7)

In a power generation system using a fuel cell operating in an independent operation mode,
A fuel cell stack for producing direct current power;
Conversion means for converting the DC power produced by the fuel cell stack into AC power;
After calculating the surplus power by comparing the power required by the load (hereinafter referred to as the first power) with the AC power converted by the conversion means (hereinafter referred to as the second power), a predetermined power (hereinafter referred to as compensation power) is calculated from the surplus power. Is transferred to the battery management means and consumes the remaining power (hereinafter referred to as power consumption), and transfers the third power obtained by subtracting the surplus power from the second power to the instantaneous power compensation means, wherein the second power is the first power. Surplus power consumption means for transferring the second power to the instantaneous power compensation means when less than or equal to;
Battery management means for charging the battery using the compensation power received from the surplus power consumption means; And
The third power is supplied to the load. When the second power is received, the second power is supplied to the load when the second power is the same as the first power. The instantaneous power compensation means for supplying the load after compensating the second power in association with the battery management means;
Power generation system using a fuel cell comprising a.
The method of claim 1,
The surplus power consumption means,
When the second power is less than the first power, the power generation system using a fuel cell, characterized in that for transmitting the second power to the instantaneous power compensation means.
The method of claim 1,
The surplus power consumption means,
A first sensing unit measuring the first power;
A second sensing unit measuring the second power;
The surplus power is calculated by comparing the first power sensed by the first detector with the second power sensed by the second detector, and managing the compensation power when the second power exceeds the first power. Means for transmitting the power consumption to the resistive load and transferring the third power to the instantaneous power compensating means, and compensating the second power for the instantaneous power if the second power does not exceed the first power. A control unit for transmitting to the means; And
The resistance load for converting the power consumption received from the control unit into thermal energy
Power generation system using a fuel cell comprising a.
The method according to any one of claims 1 to 3,
The conversion means,
A DC-DC converter for converting a low voltage DC power produced by the fuel cell stack into a DC power of a predetermined level; And
DC-AC converter for converting the DC power converted by the DC-DC converter to a predetermined level into AC power
Power generation system using a fuel cell comprising a.
The method of claim 4, wherein
The battery management means,
A battery storing the compensation power supplied from the surplus power consumption means; And
A power supply unit for converting the DC power output from the battery into AC power to supply to the instantaneous power compensation means
Power generation system using a fuel cell comprising a.
The method of claim 5, wherein
Monitoring unit that switches to independent operation mode when detecting a failure of power system
Power generation system using a fuel cell further comprising.
The method according to claim 6,
The fuel cell stack,
A power generation system using a fuel cell, characterized in that to produce direct current power by electrochemical reaction between oxygen and hydrogen.

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