JP2016126822A - Solid-state polymer type fuel battery power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-state polymer type fuel battery power generation system that can suppress deterioration of a cell even when a request power amount from a load rapidly increases in a short time.SOLUTION: In a solid polymer type fuel battery power generation system 100, plural sub stacks 111, 112 are connected so that a flow passage of gas 1, 2 forms a series loop, thereby configuring a stack 110, gas bombs 130, 160 are connected to gas reception entrances of the sub stacks 111, 112 respectively, and power generation operation is performed while the sub stacks 111, 112 for first supplying gas 1, 2 from the gas bombs 130, 160 to the stack 110 are successively changed over with time lapse so that the sub stacks 111, 112 located at the most downstream side in the flow direction of the gas 1, 2 is located at the most upstream side in the flow direction of the gas 1, 2. The solid polymer type fuel battery power generation system 100 has a current variation speed suppressing device 170 for suppressing the current variation speed of the stack 110 to 50A/μs or less.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a polymer electrolyte fuel cell power generation system.

  A polymer electrolyte fuel cell power generation system includes a fuel electrode having gas permeability and a cell sandwiching a solid polymer electrolyte having proton conductivity at an oxidization electrode, and a fuel gas flow channel for flowing a fuel gas such as hydrogen gas. A stack in which a plurality of oxidant gas flow grooves, which are formed on one side and circulate an oxidant gas such as oxygen gas, and separators formed on the other side are stacked, and the fuel gas flow of the separator of the stack Fuel gas supply means for supplying fuel gas to the groove, and oxidizing gas supply means for supplying oxidizing gas to the oxidizing gas flow groove of the separator of the stack are provided.

  In such a polymer electrolyte fuel cell power generation system, the fuel gas is supplied from the fuel gas supply means to the fuel gas flow groove of the separator of the stack, and the oxidizing gas flow of the separator of the stack is supplied from the oxidizing gas supply means. When an oxidizing gas is supplied to the groove, in the cell of the stack, the fuel gas and the oxidizing gas react electrochemically to generate electric power and water is generated.

  If the water produced | generated with this electrochemical reaction will stay in the said flow groove of the said separator, it will inhibit the electrochemical reaction of the said gas in the said cell. For this reason, in the fuel cell power generation system, by supplying the gas more than the amount necessary for the electrochemical reaction to the flow channel of the separator of the stack, the water generated by the electrochemical reaction is supplied. The excess gas that has not been consumed in the electrochemical reaction flows out of the flow channel of the separator and is discharged to the outside of the stack for gas-liquid separation, and the recovered gas is blown into the stack with a blower or the like. It is supplied again to be recycled.

  By the way, in the polymer electrolyte fuel cell power generation system as described above, in order to improve the power efficiency of the entire system, a plurality of sub-channels are formed so that the fuel gas flow path and the oxidizing gas flow path are in a series loop shape. The stacks are connected to form a stack, and the fuel gas supply means is connected to the fuel gas inlet of each substack, and the oxidizing gas supply means is connected to the oxidizing gas inlet of each substack. While sequentially switching the sub stacks that supply gas first from the gas supply means to the stack so that the sub stack located on the most downstream side in the flow direction is positioned on the most upstream side in the flow direction of the gas. By performing the power generation operation, an amount of the gas necessary for the electrochemical reaction is supplied from the gas supply means to the stack. Only in so as to be discharged water in the sub-stack, and to be omitted blower or the like, so-called blower-less type has been proposed (see Patent Document 1 and 2).

JP 2008-147178 A JP 2008-147179 A JP-A-7-057553

  In the polymer electrolyte fuel cell power generation system as described above, when the amount of power required from the load increases rapidly in a short time, the gas near the cell inside the sub stack becomes steeply insufficient, There has been a problem that the cell electrode is likely to be deteriorated.

  In view of the above, an object of the present invention is to provide a polymer electrolyte fuel cell power generation system capable of suppressing deterioration of a cell even when a required power amount from a load rapidly increases in a short time. And

  In order to solve the above-described problem, the polymer electrolyte fuel cell power generation system according to the first invention includes a plurality of sub-stacks so that the flow path of the fuel gas and the flow path of the oxidizing gas are in a series loop shape. The fuel gas supply means is connected to the fuel gas inlet of each of the sub-stacks, and the oxidizing gas supply means is connected to the oxidizing gas inlet of each of the sub-stacks. The sub-stack that first supplies the fuel gas from the fuel gas supply means to the stack so that the sub-stack located on the most downstream side in the flow direction of the fuel gas is positioned on the most upstream side in the flow direction of the fuel gas. And the sub stack located on the most downstream side in the flowing direction of the oxidizing gas is positioned on the most upstream side in the flowing direction of the oxidizing gas. In the polymer electrolyte fuel cell power generation system that performs power generation operation while sequentially switching the sub-stack that first supplies the oxidizing gas to the stack from the oxidizing gas supply means, the load connected to the stack And a current change rate suppression device that suppresses the current change rate of the stack to 50 A / μs or less.

  The polymer electrolyte fuel cell power generation system according to a second aspect of the present invention is the first aspect of the invention, wherein the secondary battery connected to the load so as to be in parallel with the stack, and the current change rate suppression From the supply power amount measuring means for measuring the amount of power supplied to the load from the apparatus, the required power amount measuring means for measuring the required power amount of the load, the supplied power amount measuring means, and the required power amount measuring means And a control means for controlling the switch so as to supply the required power amount to the load based on the above information.

  A polymer electrolyte fuel cell power generation system according to a third aspect of the present invention is the second aspect of the invention, comprising a secondary battery power amount measuring means for measuring the power amount of the secondary battery, wherein the control means includes the The switch is controlled so as to supply power from the stack to the secondary battery based on information from the secondary battery power amount measuring means.

  According to the polymer electrolyte fuel cell power generation system of the present invention, the current change rate suppression device suppresses the current change rate of the stack to 50 A / μA or less, so that the required power amount from the load is rapidly increased in a short time. Even if it increases, it is possible to prevent a shortage of gas in the vicinity of the cell in the sub stack, and to suppress the deterioration of the cell.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of the gas distribution system of main embodiment of the polymer electrolyte fuel cell power generation system which concerns on this invention, A is a schematic block diagram of the distribution system of fuel gas, B is schematic structure of the distribution system of oxidizing gas FIG. It is a schematic block diagram of the electric power supply system of main embodiment of the polymer electrolyte fuel cell power generation system which concerns on this invention. FIG. 2 is an operation explanatory diagram of a fuel gas distribution system of the polymer electrolyte fuel cell power generation system of FIG. 1. FIG. 2 is an operation explanatory diagram of an oxidizing gas distribution system of the solid bitter fuel cell power generation system of FIG. 1.

  Embodiments of a polymer electrolyte fuel cell power generation system according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments described with reference to the drawings.

<Main embodiment>
A main embodiment of a polymer electrolyte fuel cell power generation system according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, a fuel cell having a gas permeability and an oxidation electrode sandwiched between a polymer electrolyte body having proton conductivity and a hydrogen gas 1 having a concentration of 99% or more, which is a fuel gas, circulates. A plurality of gas flow grooves that are formed by alternately laminating a plurality of oxidizing gas flow grooves that are formed on one surface and have an oxygen gas 2 having a concentration of 99% or more, which is an oxidizing gas, are formed on the other surface. The first and second sub-stacks 111 and 112 in this embodiment are connected so that the fuel gas flow path is in a series loop shape (see FIG. 1A), and the oxidizing gas flow path is in series. The stack 110 is configured by being connected in a loop shape (see FIG. 1B).

  As shown in FIG. 1A, a hydrogen gas cylinder 130 as a fuel gas supply means is connected to each fuel gas inlet of each of the sub-stacks 111 and 112 via electromagnetic two-way valves 101 and 102, respectively. ing. Between the fuel gas outlet of the first sub-stack 111 and the fuel gas inlet of the second sub-stack 112, there is a drain trap 121 which is a gas-liquid separation means for fuel gas and two electromagnetic types A mold valve 103 is interposed. Between the fuel gas outlet of the second sub-stack 112 and the fuel gas inlet of the first sub-stack 111, there is a drain trap 122 which is a gas-liquid separation means for fuel gas and two electromagnetic types A mold valve 104 is interposed.

  As shown in FIG. 1B, an oxygen gas cylinder 160 as an oxidizing gas supply means is connected to each oxidizing gas inlet of each of the sub-stacks 111 and 112 via electromagnetic two-way valves 141 and 142, respectively. ing. Between the oxidizing gas outlet of the first sub-stack 111 and the oxidizing gas inlet of the second sub-stack 112, there is a drain trap 151 which is a gas-liquid separation means for oxidizing gas and two electromagnetic types. A mold valve 143 is interposed. Between the oxidizing gas outlet of the second sub-stack 112 and the oxidizing gas inlet of the first sub-stack 111, there are a drain trap 152 which is a gas-liquid separation means for oxidizing gas and two electromagnetic types. A mold valve 144 is interposed.

  As shown in FIG. 2, the negative electrode plate for electric extraction of the first sub-stack 111 and the positive electrode plate for electric extraction of the second sub-stack 112 are electrically connected. The positive electrode plate for electric extraction of the first sub-stack 111 and the negative electrode plate for electric extraction of the second sub-stack 112 are electrically connected to a load L.

  A current change rate suppression device 170 that suppresses the current change rate of the substacks 111 and 112 to 50 A / μs or less is connected between the positive electrode plate for electrical extraction of the first substack 111 and the load L. Has been. Between the current change rate suppressing device 170 and the load L, the positive electrode side of the secondary battery 180 is connected via a switch 181. Between the negative electrode plate for electrical extraction of the second sub-stack 112 and the load L, the negative electrode side of the secondary battery 180 is connected via the switch 181. That is, the secondary battery 180 is connected to the load via the switch 181 so as to be in parallel with the stack 110.

  Connected between the current change rate suppressing device 170 and the switch 181 is a voltmeter 191 which is a supply power amount measuring means for measuring the supplied power amount from the current change rate suppressing device 170 to the load L. ing. Connected between the switch 181 and the load L is a voltmeter 192 which is required power amount measuring means for measuring the required power amount of the load L. Between the positive electrode side of the secondary battery 180 and the switch 181, a voltmeter 193, which is a secondary battery power amount measuring means for measuring the power amount of the secondary battery 180, is connected.

  The voltmeters 191 to 193 are electrically connected to an input unit of a control device 190 which is a control means. The output unit of the control device 190 is electrically connected to the switch 191, and the control device 190 can control the operation of the switch 191 based on information from the voltmeters 191 to 193. (The details will be described later.)

  Further, as shown in FIG. 1, the output unit of the control device 190 is also electrically connected to the valves 101 to 106 and 141 to 146, and the control device 190 is connected to a built-in timer (not shown). On the basis of the information (operation time), the opening and closing of the valves 101 to 104 and 141 to 144 can be controlled (details will be described later).

  In the present embodiment, the valves 101 and 102 and the like constitute the fuel gas most upstream position switching means, the valves 103 and 104 and the like constitute the fuel gas most downstream position switching means, and the valves 141 and 142 The most upstream position switching means for oxidizing gas is configured by the above, and the most downstream position switching means for oxidizing gas is configured by the valves 143, 144 and the like.

  In such a polymer electrolyte fuel cell power generation system 100 (blowerless type) according to this embodiment, the control device 190 opens and closes the valve valves 101 to 104 and 141 to 144 in the same manner as in Patent Document 2. Is switched from the gas cylinders 130 and 160 to the stack 110 so that the sub stacks 111 and 112 located on the most downstream side in the flow direction of the gases 1 and 2 are positioned on the most upstream side in the flow direction. The sub stacks 111 and 112 to which the gases 1 and 2 are first supplied are sequentially switched over time corresponding to the operation elapsed time (see FIGS. 3 and 4).

  Thereby, in the polymer electrolyte fuel cell power generation system 100 according to the present embodiment, the gas 1 and 2 can be circulated and reused by using a blower or the like, as in the patent documents 1 and 2. The power generation operation can be performed while discharging the water 3 staying in the substacks 111 and 112 from the substacks 111 and 112.

  When such a power generation operation is performed, if the required power amount from the load L increases rapidly in a short time and the current change rate of the stack 110 is likely to exceed 50 A / μs, the current change The speed suppression device 170 suppresses the current change speed of the stack 110 to 50 A / μs or less.

  Thereby, it is possible to prevent the gas 1 and 2 from being steeply short in the vicinity of the cell inside the sub stacks 111 and 112, and to suppress deterioration of the electrode of the cell.

  Thus, as a result of the current change rate suppressing device 170 suppressing the current change rate of the stack 110 to 50 A / μs or less, the required power amount from the load L cannot be supplied from the stack 110, that is, the voltmeter When the value of 192 becomes larger than the value of the voltmeter 191, the control device 190 controls the switch 181 to turn on the switch 181 based on information from the voltmeters 191 and 192. By doing so, the secondary battery 180 and the load L are connected. Accordingly, the secondary battery 180 supplies power so as to compensate the load L for the amount of power that is insufficient from the amount of power supplied from the stack 110 to the load L.

  When the stack 110 can supply the required power amount to the load L, that is, when the value of the voltmeter 191 becomes equal to the value of the voltmeter 192, the control device 190 Based on the information from the total 191, 192, the switch 181 is controlled to be “OFF”, thereby disconnecting the connection between the secondary battery 180 and the load L.

  In this way, the secondary battery 180 supplies insufficient power to the load L, and the amount of charge of the secondary battery 180 becomes a specified value or less, that is, the voltage of the secondary battery 180. Is less than a specified value, the control device 190 controls the switch 181 to turn on the switch 181 based on the information from the voltmeter 193, thereby The stack 110 is connected. Accordingly, the secondary battery 180 is charged from the stack 110.

  Then, when the amount of charge of the secondary battery 180 reaches a reference value, that is, when the voltage of the secondary battery 180 reaches the reference value, the control device 190, based on the information from the voltmeter 193, the By controlling the switch 181 so that the switch 181 is turned off, the connection between the secondary battery 180 and the stack 110 is disconnected.

  Hereinafter, by repeating the above-described operation, the polymer electrolyte fuel cell power generation system 100 can continue the power generation operation while suppressing deterioration of the electrodes of the cells in the substacks 111 and 112.

  Therefore, according to the polymer electrolyte fuel cell power generation system 100 according to the present embodiment, even if the required power amount from the load L increases rapidly in a short time, it is possible to suppress cell deterioration.

  In addition, since the amount of power that is insufficient from the amount of power supplied from the stack 110 to the load L is compensated for from the secondary battery 180 to the load L, the required power amount from the load L is short. Even if the deterioration of the cell is suppressed when it suddenly increases, the required power amount can be supplied to the load L.

  In addition, when the secondary battery 180 becomes insufficiently charged, the secondary battery 180 is charged from the stack 110, so that the insufficient charging of the secondary battery 180 can be solved while continuing to supply power to the load L.

  Here, the current change rate suppression device 170 suppresses the current change rate of the stack 110 (the sub-stacks 111 and 112) to 50 A / μs or less, but suppresses the current change rate to 15 A / μs or less. It is preferable to suppress the current change rate, and it is particularly preferable to suppress the current change rate to 10 A / μs or less.

  This is because when the stack 110 (the sub-stacks 111 and 112) is operated at a pressure in the gas flow path of 300 kPaG (400 kPa) or more when the current change rate is suppressed to 50 A / μs or less, the voltage drops. When the ratio (decrease ratio of the voltage value after 1000 current changes with respect to the initial voltage value) is suppressed to 3% or less and the current change rate is suppressed to 15 A / μs or less, a gas flow path of at least 100 kPaG (200 kPa) or more When operating at internal pressure, when the voltage drop rate is suppressed to 3% or less and the current change rate is suppressed to 10 A / μs or less, the operation is performed at a pressure in the gas flow path of at least 0 kPaG (100 kPa) or more. This is because the voltage drop rate is further suppressed to 1% or less.

<Other embodiments>
In the above-described embodiment, the hydrogen gas cylinder 130 filled with hydrogen gas 1 having a concentration of 99% or more is applied as the fuel gas supply means, and oxygen filled with oxygen gas 2 having a concentration of 99% or more is used as the oxidizing gas supply means. Although the case where the gas cylinder 160 is applied has been described, as other embodiments, for example, as a fuel gas supply means, a hydrogen gas generator that generates a hydrogen gas 1 having a concentration of 99% or more, or a hydrogen gas 1 having a concentration of 99% or more. As an oxidizing gas supply means, an oxygen gas generator for generating oxygen gas 2 having a concentration of 99% or higher, or an oxygen gas for manufacturing oxygen gas 2 having a concentration of 99% or higher is used as an oxidizing gas supply means. It is also possible to apply a manufacturing apparatus or the like.

  Further, in each of the above-described embodiments, the case of the stack 110 in which the two sub-stacks 111 and 112 are connected so as to form a fuel gas flow path and an oxidizing gas flow path in a series loop shape has been described. The present invention is not limited to this, and other embodiments include, for example, a stack in which three or more sub-stacks are connected so that the fuel gas flow path and the oxidizing gas flow path are in a series loop shape. However, it can be applied in the same manner as in the above-described embodiment, and the same effect as in the above-described embodiment can be obtained.

  The polymer electrolyte fuel cell power generation system according to the present invention can prevent a shortage of gas near the cells inside the sub stack even if the required power amount from the load increases rapidly in a short time, Since cell deterioration can be suppressed, it can be used extremely beneficially in various industries.

DESCRIPTION OF SYMBOLS 1 Hydrogen gas 2 Oxygen gas 3 Water 100 Polymer electrolyte fuel cell power generation system 101-104, 141-144 Valve | bulb 110 Stack 111 1st stack 112 2nd stack 121,122,151,152 Drain trap 130 Hydrogen gas cylinder 160 Oxygen gas cylinder 170 Current change rate suppressing device 180 Secondary battery 181 Switch 190 Controller 191 to 193 Voltmeter

Claims (3)

A plurality of sub-stacks are connected to form a fuel gas flow path and an oxidizing gas flow path in a series loop, and a fuel gas supply means is connected to the fuel gas inlet of each sub-stack. In addition, the oxidizing gas supply means is connected to the oxidizing gas inlet of each of the sub-stacks so that the sub-stack located on the most downstream side in the fuel gas flow direction is positioned on the most upstream side in the fuel gas flow direction. The sub-stack that first supplies the fuel gas from the fuel gas supply means to the stack is sequentially switched over time, and the sub-stack located on the most downstream side in the flow direction of the oxidizing gas is passed through the flow of the oxidizing gas. The oxidizing gas supply means first supplies the oxidizing gas to the stack so as to be positioned on the most upstream side in the direction. While over time sequentially switched, in a solid polymer fuel cell power generation system which performs power generation operation,
A solid polymer fuel characterized by comprising a current change rate suppressing device connected between the load connected to the stack and the stack and suppressing the current change rate of the stack to 50 A / μs or less. Battery power generation system. In the polymer electrolyte fuel cell power generation system according to claim 1,
A secondary battery connected to the load so as to be in parallel with the stack;
Supply power amount measuring means for measuring the amount of power supplied to the load from the current change rate suppression device,
Required power amount measuring means for measuring the required power amount of the load;
And a control means for controlling the switch so as to supply the required power amount to the load based on information from the supplied power amount measuring means and the required power amount measuring means. Polymer fuel cell power generation system. The polymer electrolyte fuel cell power generation system according to claim 2,
A secondary battery energy measuring means for measuring the energy of the secondary battery;
The control means controls the switch so as to supply electric power from the stack to the secondary battery based on information from the secondary battery electric energy measuring means. Fuel cell power generation system.

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