Evaluation device, evaluation method, and program for chemical reaction cell

Abstract

[Problem] To provide an evaluation device, an evaluation method, and a program for a chemical reaction cell that enable more accurate and precise quantitative evaluation of the performance of a cell stack itself in a furnace by reducing unevenness in the temperature distribution of the cell stack during performance evaluation. [Solution] The present invention is provided with: a furnace 2 that covers a specimen T, which is a chemical reaction cell; first heaters 3 that are provided on inner wall sections 21 of the furnace 2; a base plate 4 that is provided on a bottom surface 23 of the furnace 2 and that supports the specimen T; a second heater 5 that is provided in the base plate 4; and a control unit 6 that controls the individual outputs of the first heaters 3 and the second heater 5.

Description

Evaluation apparatus, evaluation method, and program for chemical reaction cells

[0001] This invention relates to an apparatus, method, and program for evaluating chemical reaction cells.

[0002] The performance of hydrogen-related cell stacks, such as solid oxide fuel cell cell stacks or solid oxide electrolytic cell stacks (SOFC / SOEC), is greatly affected by the degree of temperature distribution unevenness. Therefore, when evaluating the performance of a cell stack, uniformly controlling the surface temperature of the operating hydrogen-related cell stack is extremely important for accurately quantitatively evaluating the cell stack's inherent performance.

[0003] For example, Patent Document 1 discloses a method for achieving uniformity of the cell plane temperature in a solid oxide fuel cell stack (SOFC) by providing a heat pipe in the separator located between the cell stacks. Patent Document 2 also discloses a technique for preventing a decrease in the furnace temperature when evaluating performance by supplying a heated oxidizer to the test specimen (intermediate temperature solid oxide fuel cell) inside the furnace.

[0004] However, when evaluating the performance of SOFC / SOEC specimens, for example, a base plate, which is a block used to fix the specimen, is provided at the bottom of the furnace. It is unavoidable that the heat from the specimen will dissipate through this base plate. Therefore, even if the cell stack is heated using heat pipes or oxidizers as described above, it was difficult to eliminate uneven temperature distribution.

[0005] To address this problem, an evaluation method has been proposed that excludes only the nearest cell directly in contact with the base plate from evaluation, thereby eliminating the influence of uneven temperature distribution. However, excluding some cells in this way is undesirable because it reduces the number of effective samples. Furthermore, even if not to the same extent as the cells in contact with the base plate, nearby cells also experience some heat dissipation through the base plate. Therefore, simply excluding the cells in contact with the base plate makes it difficult to eliminate the influence of uneven temperature distribution.

[0006] Japanese Patent Application Laid-Open No. 9-270263 Patent No. 5284289

[0007] Therefore, in view of the above-mentioned circumstances, the present invention aims to provide an evaluation device for chemical reaction cells that can reduce the unevenness of the temperature distribution of the cell stack inside the furnace during performance evaluation and more accurately and precisely quantitatively evaluate the inherent performance of the cell stack.

[0008] In view of the current situation, the inventors conducted thorough research and found that by providing a heater on the base plate, which was the cause of heat dissipation in the cell stack, the temperature of the cell stack can be efficiently controlled through the cells that are in direct contact with the heater, thereby reducing unevenness in the temperature distribution of the cell stack. This led to the completion of the present invention.

[0009] In other words, the present invention encompasses the following inventions: (1) An evaluation apparatus for a chemical reaction cell which is a test specimen, comprising: a furnace covering the test specimen; a first heater provided on the inner wall of the furnace; a base plate provided on the bottom surface of the furnace to support the test specimen; a second heater provided on the base plate; and a control unit that controls the outputs of the first heater and the second heater, respectively.

[0010] (2) An evaluation apparatus for a chemical reaction cell according to (1), wherein the test specimen is a solid oxide fuel cell stack or a solid oxide electrolytic cell stack (SOFC / SOEC).

[0011] (3) The chemical reaction cell evaluation apparatus according to (1) or (2), wherein the control unit includes a temperature change control unit for raising or lowering the temperature of the test specimen in the furnace, and a temperature uniformization control unit for uniformizing the surface temperature of the test specimen in the furnace.

[0012] (4) The chemical reaction cell evaluation apparatus according to (3), wherein the temperature change control unit feeds back the temperature of the region in the test specimen where the temperature change per unit time during heating or cooling is smallest, as the temperature control target.

[0013] (5) An evaluation apparatus for a chemical reaction cell according to any one of (1) to (4), further comprising a base plate contact surface thermometer for measuring the temperature of the cell surface on the surface of the specimen that is in contact with the base plate, and a target thermometer for measuring the temperature of the cell surface on the surface of the specimen that is located on the opposite side from the cell surface in contact with the base plate, wherein the control unit controls the outputs of the first heater and the second heater so that the temperature of the base plate contact surface thermometer approaches the temperature of the target thermometer.

[0014] (6) An evaluation apparatus for a chemical reaction cell according to any one of (1) to (5), wherein the control circuit of the control unit is equipped with a thyristor.

[0015] (7) An evaluation apparatus for a chemical reaction cell according to any one of (1) to (6), wherein the second heater is a cartridge heater.

[0016] (8) An evaluation apparatus for a chemical reaction cell according to any one of (1) to (7), wherein the base plate has a fluid channel connected to the test specimen for operating the test specimen, and the second heater is installed so as to sandwich the fluid channel of the base plate.

[0017] (9) An evaluation apparatus for a chemical reaction cell according to any one of (1) to (8), wherein the furnace has a hood structure that can be raised and lowered, and the first heater is provided on the inner wall of the hood.

[0018] (10) An evaluation apparatus for a chemical reaction cell according to any one of (1) to (9), wherein the first heater is provided in each of the three zones into which the inner wall portion is divided: upper, middle, and lower.

[0019] (11) An evaluation apparatus for a chemical reaction cell according to any one of (1) to (10), wherein the furnace is provided with a gas inlet for circulating a cooling gas into the space inside the furnace, a gas outlet for circulating a cooling gas, and a fan for forced circulation.

[0020] (12) A method for evaluating a chemical reaction cell which is a test specimen, wherein a furnace is provided which covers the test specimen and which has a first heater on its inner wall and a base plate on its bottom surface for supporting the test specimen, a second heater is provided on the base plate, a control unit is provided which controls the output of the first heater and the second heater, and the control unit controls the first heater and the second heater to reduce unevenness in the surface temperature of the test specimen.

[0021] (13) A program for an evaluation apparatus for a chemical reaction cell comprising a furnace covering a test specimen, a first heater provided on the inner wall of the furnace, a base plate provided on the bottom surface of the furnace to support the test specimen, and a second heater provided on the base plate, wherein the program causes a computer to function as a control unit that controls the outputs of the first heater and the second heater.

[0022] According to the chemical reaction cell evaluation apparatus, evaluation method, and program of the present invention, as described above, it is possible to reduce the unevenness of the temperature distribution of the cell stack inside the furnace during performance evaluation and to quantitatively evaluate the inherent performance of the cell stack more accurately and precisely.

[0023] An explanatory diagram showing an evaluation device 1 according to an embodiment of the present invention. An explanatory diagram showing a base plate 4 supporting a test specimen T according to an embodiment of the present invention. An explanatory diagram showing the structure of the base plate 4 shown in Figure 2. An explanatory diagram showing a furnace 2 for cooling down the test specimen T according to an embodiment of the present invention. An explanatory diagram showing a furnace 2 for cooling down the test specimen T according to an embodiment of the present invention. A block diagram showing the circuit configuration of the control unit 6 according to an embodiment of the present invention. A block diagram showing the circuit configuration of the control unit 6 according to an embodiment of the present invention. A block diagram showing the circuit configuration of the temperature control control unit 63 according to an embodiment of the present invention. A block diagram showing the circuit configuration of the temperature control control unit 63 according to an embodiment of the present invention. An evaluation device 1 for a chemical reaction cell.

[0024] Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0025] As shown in Figure 1, the chemical reaction cell evaluation apparatus 1 according to the present invention (hereinafter referred to as "evaluation apparatus 1") comprises a furnace 2 that covers a test specimen T, which is a chemical reaction cell, such as a hydrogen-related cell stack; a first heater 3 provided on the inner wall portion 21 of the furnace 2; a base plate 4 provided on the bottom surface 23 of the furnace 2 to support the test specimen T; a second heater 5 provided on the base plate 4; and a control unit 6 that controls the outputs of the first heater 3 and the second heater 5.

[0026] With the evaluation device 1 configured in this way, the control unit 6 controls the first heater 3 installed in the furnace 2 to heat the test specimen T, and also controls the second heater 5 provided on the base plate 4 to heat the cells of the test specimen T in contact with the base plate 4 to the same extent as the other cells of the test specimen T. This reduces heat dissipation in the cells of the test specimen T that are in contact with the base plate 4. Since the entire test specimen T is heated to a similar temperature, the evaluation device 1 makes it less likely for unevenness to occur in the temperature distribution on the surface of the test specimen T, and allows for accurate and precise quantitative evaluation of the performance of the hydrogen-related cell stack, which is the test specimen T.

[0027] The hydrogen-related cell stack that is the test specimen T of the present invention is preferably a solid oxide fuel cell (SOFC) and a solid oxide fuel cell stack configured by connecting multiple SOFCs, a solid oxide electrolytic cell (SOEC) and a solid oxide electrolytic cell stack configured by connecting multiple SOECs, or a molten carbonate fuel cell (MCFC) and a molten carbonate fuel cell stack configured by connecting multiple MCFCs. In other words, any hydrogen-related cell or cell stack thereof that generates a chemical reaction at high temperature is acceptable.

[0028] Furnace 2 is a heating furnace that heats the covered test specimen T with a first heater 3 provided on the inner wall portion 21 and a second heater 5 provided on the base plate 4 located on the bottom surface 23 of furnace 2. The shape of furnace 2 is preferably a cubic box shape as shown in Figure 1, but it may also be a tubular cylindrical shape, as long as it can cover the test specimen T. Furnace 2 may be a box-type furnace that opens and closes with a single-leaf door, a double-leaf door, a suspended door, etc., a trolley furnace, or a lifting furnace, and it is preferable to have a hood structure as shown in Figure 1. It is acceptable as long as it is possible to install the base plate 4 inside the furnace.

[0029] If the furnace 2 has the hood structure described above, as shown in Figure 1, a housing 29 is provided on the outside of the furnace 2 to enclose it. The furnace 2 is raised and lowered by a lifting mechanism (not shown), and a well-known mechanism such as a hydraulic system, an electric lifter, or a screw jack is used as the lifting mechanism. Preferably, the furnace 2 with the hood structure itself is raised and lowered within the housing 29, or the bottom surface 23 on which the base plate 4 is provided may be raised and lowered within the housing 29, or the housing 29 may be raised and lowered separately from the furnace 2. Insulation materials such as fiberglass, ceramic fiber, or rock wool are used on the inner wall portion 21 of the furnace 2 and the inner wall of the housing 29 to prevent the high temperature inside the furnace 2 from leaking to the outside. In the following description, a cubic-shaped furnace 2 with a hood structure that is raised and lowered within the housing 29 will be described as an example.

[0030] The first heater 3 is provided on the inner wall 21 of the hood structure of the furnace 2. The first heater 3 heats the atmosphere inside the furnace 2 and raises the temperature of the test specimen T supported on the base plate 4 inside the same furnace 2. The first heater 3 can be made of silicon carbide (SiC) or molybdenum disilide (MoSi ２ A ceramic heater primarily composed of ) , a resistance wire heater using a ferritic iron-chromium-aluminum alloy (FeCrAl alloy), and a carbon heater such as a graphite heater are used, as long as they can heat the inside of furnace 2 to 600°C or higher.

[0031] Furthermore, it is preferable that multiple first heaters 3 are provided in the inner wall portion 21, with each heater located on the inner side of the furnace 2. In this case, it is preferable to divide the inner wall portion 21 into three zones: upper, middle, and lower, with each zone having a first heater 3. There are no limitations on how the upper, middle, and lower sections are divided; they can be appropriately determined according to specifications such as the size and material of the test specimen T. Also, the zones are not limited to three; they can be divided into two, four or more zones.

[0032] In Figure 1, the first heater 3 is only provided on two opposing inner wall portions 21, that is, on the left and right inner wall portions 21 that face each other via the specimen T. However, it may also be provided on the other two sides so that the first heater 3 is provided on all four inner wall portions 21.

[0033] The base plate 4 is, for example, a flat-plate type manifold and is installed on the bottom surface 23 of the furnace 2. Since the base plate 4 is actively temperature-controlled by the second heater described later, aluminum oxide is a good material, but it can also be a metal such as molybdenum or tungsten, or a ceramic such as silicon carbide, as long as electrical insulation can be ensured. It is preferable that it has heat resistance, high thermal conductivity, and electrical insulation.

[0034] The base plate 4 is provided with a mounting structure on the surface in contact with the specimen T, for example, a substantially cylindrical projection 41 as shown in Figures 2 and 3, for supporting the specimen T. In this case, the specimen T is provided with a recess 40 as a mounting structure corresponding to the projection 41. The base plate 4 is provided not only with the mounting structure but also with a fluid channel 42 for supplying fuel gas such as hydrogen or methane, or supply fluid such as oxygen, to operate the specimen T, and / or for discharging exhaust fluid, which is a product of the chemical reaction, such as water vapor or carbon dioxide. For example, when the projection 41 of the base plate 4 is connected to the recess 40 of the specimen T, one end of the fluid channel 42 provided on the projection 41 is connected to the inside of the specimen T. This allows the fluid channel 42 to supply the supply fluid and / or discharge the exhaust fluid.

[0035] When the test specimen T is a solid oxide fuel cell, different fluids are supplied to the fluid flow path 42 for the fuel electrode (anode) and the air electrode (cathode), and the products generated by the chemical reaction are discharged respectively. For example, when hydrogen (H ２ ) is supplied to the fuel electrode of the test specimen T and air in the atmosphere is supplied to the air electrode of the test specimen T, oxygen (O ２ ) in the air is converted into oxygen ions (O ２－ ) through the electrolyte of the test specimen T, and hydrogen, which is the fuel gas, reacts with the oxygen ions, and water vapor (H ２ O) is generated as a product. The fuel electrode of the test specimen T discharges the water vapor generated by the chemical reaction from the fluid flow path 42, and the air electrode of the test specimen T also discharges the excess oxygen that was not used in the chemical reaction from the fluid flow path 42.

[0036] When the test specimen T is a solid oxide electrolysis cell, for example, when water vapor is supplied to the fuel electrode of the test specimen T and air is supplied to the air electrode of the test specimen T, a reduction reaction proceeds at the fuel electrode of the test specimen T, and hydrogen is generated as a product. The fuel electrode of the test specimen T discharges the hydrogen generated by the reduction reaction from the fluid flow path 42, and the air electrode of the test specimen T also discharges the excess oxygen that was not used in the reduction reaction from the fluid flow path 42.

[0037] Although air in the atmosphere is taken as an example of the fluid supplied to the above solid oxide fuel cell, a fluid containing oxygen at a high concentration or a fluid of pure oxygen may also be used, or synthesis gas (H ２ + CO), or hydrocarbon fuel gas such as methane (CH ４ ) or propane (C ３ H ８ ). Also, although water vapor is taken as an example of the fluid supplied to the above solid oxide electrolysis cell, carbon dioxide (CO ２ ) or synthesis gas (H ２ O + CO ２ ) may also be used.

[0038] The second heater 5 is provided on the base plate 4 and heats the base plate 4. As the second heater 5, a cartridge heater using a ceramic sheath or a metal sheath is preferable, and a ceramic heater having high heat resistance such as silicon carbide or aluminum oxide may be used, and various known heaters can be used.

[0039] When the second heater 5 is a cartridge heater, the base plate 4 which is a manifold is provided with installation holes 43 for providing the second heater 5 as shown in FIGS. 2 and 3 according to the quantity of the second heater 5. When the surface of the base plate 4 in contact with the specimen T is taken as the upper surface, the installation holes 43 extend from one side surface of the base plate 4 to the other side surface in parallel with the surface in contact with the specimen T. At that time, the installation holes 43 are preferably provided so as to sandwich the fluid flow path 42. By providing the installation holes 43 in this way, the second heater 5 can be installed so as to sandwich the fluid flow path 42 provided in the base plate 4. The second heater 5 provided at a position sandwiching the fluid flow path 42 can not only heat the base plate 4 for each region, but also heat the fluid flowing through the fluid flow path 42 individually. Although the second heater 5 has been described using a plurality of cartridge heaters, the second heater 5 may be a single heater meandering and extending parallel to the surface in contact with the specimen T. Also in that case, it is preferably installed so as to sandwich the fluid flow path 42.

[0040] A thermometer 7 for measuring the surface temperature of the specimen T is provided on the surface of the specimen T. As shown in FIG. 1, a plurality of thermometers 7 can be provided on each surface, and it is preferable to provide them on all six surfaces of the specimen T, and they may be provided at the sides or vertices formed by the specimen T. As the thermometer 7, for example, a thermistor or a thermocouple is preferable, and any temperature sensor that can measure the surface temperature of the specimen T in a high-temperature environment may be used.

[0041] The evaluation device 1 is further provided with a temperature reduction mechanism 8 for reducing the temperature (surface temperature) of the test specimen T heated by the first heater 3 and the second heater 5. As the temperature reduction mechanism 8, for example, as shown in FIG. 4, a gas inflow portion 81 provided in the ceiling portion of the furnace 2 for allowing the gas G to flow into the space inside the furnace 2, a first gas discharge portion 82 provided in the lower portion of the furnace 2 for discharging the gas G inside the furnace 2 to the outside of the furnace 2, and a second gas discharge portion 83 provided on the bottom surface of the housing 29 for discharging the gas G discharged from the first gas discharge portion 82 to the outside of the housing 29 are provided.

[0042] The gas inflow portion 81 allows the gas G for reducing the temperature of the test specimen T to flow into the furnace 2 by an inflow means 811 such as a fan. The gas G to be introduced can be selected according to the characteristics of the test specimen T. For example, gases that efficiently transfer heat and are less affected by chemical reactions such as oxidation and reduction, such as air in the atmosphere, nitrogen gas, and argon gas, are preferable. The first gas discharge portion 82 only needs to be able to discharge the gas G inside the furnace 2 to the outside of the furnace 2. As shown in FIG. 4, a gap 821 formed by raising the furnace 2 by a lifting means is used as the first gas discharge portion 82. The first gas discharge portion 82 may be a discharge hole provided in advance in the lower portion of the furnace 2, and a discharge means such as a fan may be provided in the discharge hole. The second gas discharge portion 83 discharges the gas G discharged from the first gas discharge portion 82 to the outside of the housing 29 by a discharge means 831 such as a fan. The second gas discharge portion 83 only needs to be able to discharge the gas G discharged from the first gas discharge portion 82 to the outside of the housing 29, and may be a discharge hole without a discharge means 831.

[0043] Further, a fluid flow path 42 for supplying a supply fluid to the inside of the test specimen T and / or discharging a discharge fluid generated in the test specimen T may be used as the temperature reduction mechanism 8. In this case, as shown in FIG. 5, a temperature reduction fluid PG such as an inert gas such as nitrogen gas, argon gas, or helium gas flows into the inside of the test specimen T through the fluid flow path 42. The fluid flow path 42 can be used not only for supplying the supply fluid and discharging the discharge fluid by a switching means or the like, but also for allowing the temperature reduction fluid PG to flow into the test specimen T. Further, a flow path for allowing the temperature reduction fluid PG to flow into the test specimen T may be provided separately without using the fluid flow path 42.

[0044] As shown in Figure 4, in furnace 2, forced convection FC of gas G is generated within furnace 2 by the cooling mechanism 8, which consists of a gas inlet 81, a first gas outlet 82, and a second gas outlet 83. This forced convection FC of gas G causes each surface of the test specimen T supported by the base plate 4 to dissipate heat. In terms of the magnitude of the temperature gradient during heat dissipation, for example, if the surface of the test specimen T in contact with the base plate 4 is the bottom surface, the temperature gradient is about the same for the bottom and top surfaces, while the temperature gradient on the sides is smaller than that of the bottom and top surfaces. This is because the top surface is more easily exposed to the forced convection FC of gas G than the sides, and the base plate 4 also acts as a heat exchanger on the bottom surface. Consequently, as the difference in temperature gradients generated on each surface of the test specimen T gradually increases, cracks and other damage are more likely to occur in the test specimen T. Therefore, the temperature deviation is calculated using the temperatures obtained from each thermometer 7 installed on the test specimen T, and the first heater 3 and the second heater 5 are controlled to reduce the temperature deviation. In addition, the output of the cooling mechanism 8 corresponding to parts of the test specimen T that are difficult to cool by forced convection CF, such as the sides, is adjusted so that it dissipates heat more than other parts. If forced convection FC alone is insufficient, as shown in Figure 5, the cooling fluid PG may be introduced into the test specimen T through the fluid flow path 42 to generate heat exchange with the test specimen T together with the base plate 4, thereby promoting heat dissipation from the test specimen T.

[0045] The control unit 6 controls the output of the first heater 3 and the second heater 5 in order to regulate the temperature (surface temperature) of the test specimen T. Based on temperature information from the thermometer 7, the control unit 6 not only controls the output of the first heater 3 provided on the inner wall 21 of the furnace 2 and the second heater 5 provided on the base plate 4, but also controls the raising and lowering and cooling mechanisms 8 of the furnace 2. For this reason, the control unit 6 includes a temperature change control unit 61 that raises or lowers the temperature of the test specimen T inside the furnace 2, and a temperature uniformization control unit 62 that equalizes the surface temperature of the test specimen T inside the furnace 2.

[0046] The temperature change control unit 61 controls at least one of the first heater 3 and the second heater 5 to raise the temperature (surface temperature) of the test specimen T. The temperature change control unit 61 also controls the cooling mechanism 8 to lower the temperature (surface temperature) of the test specimen T. The temperature change control unit 61 identifies the region with the smallest temperature change per unit time. The temperature change control unit 61 then uses the region with the smallest temperature change per unit time as the temperature control target and controls the heating by at least one of the first heater 3 and the second heater 5, and the cooling by the cooling mechanism 8. The temperature equalization control unit 62 calculates a temperature deviation based on temperature information from multiple thermometers 7 that measure the surface temperature of each region of the test specimen T, for example. This temperature deviation may be the standard deviation or the maximum temperature difference. Based on this temperature deviation, the temperature equalization control unit 62 provides feedback to the temperature change control unit 61 so that the temperature deviation of the surface temperature in each region of the test specimen T is reduced. Upon receiving feedback from the temperature uniformity control unit 62, the temperature change control unit 61 controls the output of the first heater 3 or second heater 5 corresponding to the temperature-controlled object so that the temperature-controlled object becomes hotter than other surface areas when raising the temperature of the test specimen T. Furthermore, when lowering the temperature of the test specimen T, the temperature change control unit 61 controls the flow rate of the cooling fluid PG flowing through the fluid channel 42, for example, within the cooling mechanism 8 corresponding to the temperature-controlled object, so that the temperature-controlled object becomes colder than other surface areas.

[0047] The circuit configuration of the control unit 6 will be explained using Figures 6 and 7 as examples. For example, if we consider an evaluation device 1 in which the surface temperature of region TP2, measured by the thermometer 7, is used as the reference value among the regions TP1, TP2, and TP3 on the surface of the test specimen T, the control unit 6 in the evaluation device 1 includes a first control circuit C1 and a second control circuit C2. The region TP2 used to obtain the reference value for the surface temperature is preferably the location with the lowest cooling efficiency, which in the example above corresponds to the side surface of the test specimen T.

[0048] The first control circuit C1 includes a differentiator 101 that receives temperature information from a thermometer 7 indicating the surface temperature of region TP2, a controller 102 that performs PID control based on the input from the differentiator 101, a limiter 103 that limits the control signal from the controller 102, and an amplifier 104 that amplifies the control signal. The control signal is an adjustment signal that adjusts the output to the cooling sections F1 and F2, which correspond to the cooling mechanism 8, such as a supply section that supplies the cooling fluid PG as shown in Figure 6, and a discharge means such as a fan that forms forced convection FC in the furnace 2. When the adjustment signal is input to the cooling sections F1 and F2, the cooling rate is adjusted so that each region TP1, TP2, and TP3 on the surface of the test specimen T cools down with a gentle temperature gradient. Alternatively, if the temperature gradient of the test specimen T being cooled in the evaluation device 1 is not large, the first control circuit C1 may perform cooling control for the surface temperature of the test specimen T using only the cooling section F2, such as a discharge means such as a fan, as shown in Figure 7.

[0049] The second control circuit C2 includes a calculator 201 that calculates the temperature deviation of each region TP1, TP2, and TP3 with respect to the surface temperature of region TP2 based on temperature information indicating the surface temperatures of each region TP1, TP2, and TP3 measured by the thermometer 7; a controller 202 that performs PID control based on the temperature deviation calculated by the calculator 201; a limiter 203 that limits the control signal from the controller 202; and an amplifier 204 that amplifies the control signal. The control signal is, for example, an adjustment signal that adjusts the output to the heating sections H1, H2, and H3, which correspond to the first heater 3 provided on the inner wall 21 of the furnace 2 and the second heater 5 provided on the base plate 4, to reduce the temperature deviation from the reference value, as shown in Figures 6 and 7. When the adjustment signal is input to the heating sections H1, H2, and H3, the heat generation of the heating sections H1, H2, and H3 is adjusted so that the temperature distribution of each region TP1, TP2, and TP3 on the surface of the test specimen T becomes uniform.

[0050] Therefore, when the evaluation device 1 raises the surface temperature of the test specimen T, the control unit 6 uses the second control circuit C2 to control the temperature deviation between the heating units H1, H2, and H3 to be small. For example, if it is desired to raise the surface temperature of the test specimen T with a gentle temperature gradient, the control unit 6 may not only adjust the output to the heating units H1, H2, and H3 using the second control circuit C2, but may also use the cooling units F1 and F2 using the first control circuit C1. Furthermore, when the evaluation device 1 lowers the surface temperature of the test specimen T, which is at a high temperature, it uses the first control circuit C1 to control the cooling units F1 and F2 so that the surface temperature of the test specimen T becomes a gentle temperature gradient, and also uses the second control circuit C2 to control the temperature deviation between the heating units H1, H2, and H3 to be small.

[0051] Furthermore, as shown in Figures 1, 4 and 5, the thermometer 7 includes at least a base plate contact surface thermometer 71 and a target thermometer 72. The base plate contact surface thermometer 71 measures the temperature of the contact surface S1 on the surface of the specimen T that is in contact with the base plate 4. The target thermometer 72 measures the temperature of the opposite surface S2 on the surface of the specimen T that is located opposite to the contact surface S1 that is in contact with the base plate 4. The control unit 6 includes a temperature control unit 63 that uses the temperature of the opposite surface S2 measured by the target thermometer 72 as target temperature information for equalizing the surface temperature of the specimen T, and controls the output of the first heater 3 and the second heater 5 based on the target temperature information so that the temperature of the contact surface S1 approaches the temperature of the opposite surface S2. The temperature of the contact surface S1 of the test specimen T, which is in contact with the base plate 4 where heat dissipation is significant, is raised by the temperature control unit 63 to the same temperature as the other surface, for example, the opposite surface S2. This reduces the temperature deviation in the overall temperature distribution of the test specimen T, and the evaluation device 1 can perform a quantitative evaluation of the test specimen T with high accuracy.

[0052] The circuit configuration of the temperature control unit 63 will be explained using Figures 8 and 9 as examples. When the power supply is a DC power supply, the temperature control unit 63 includes a third control circuit C3 for controlling temperature, as shown in Figure 8. The third control circuit C3 includes a contact surface side converter 301 that converts the analog temperature signal of a first measurement point SP1 measured by a base plate contact surface thermometer 71 on the contact surface S1 of the test specimen T into digital temperature information, an opposite surface side converter 302 that converts the analog temperature signal of a second measurement point SP2 measured by a target thermometer 72 on the opposite surface S2 of the test specimen T into digital temperature information, a comparator 303 that compares the temperature information converted by the contact surface side converter 301 and the temperature information converted by the opposite surface side converter 302 and outputs a duty cycle signal, a signal generator 304 that generates an adjustment signal, such as a PWM signal, according to the duty cycle signal output by the comparator 303, and a rectifier element 305 which is a thyristor that adjusts the output of the DC power supply DC based on the adjustment signal.

[0053] As an alternative modification, when the power supply is an AC power supply, the temperature control unit 63 includes a fourth control circuit C4 for controlling temperature, as shown in Figure 9. The fourth control circuit C4 includes a contact surface side converter 401 that converts the analog temperature signal of a first measurement point SP1 measured by a base plate contact surface thermometer 71 on the contact surface S1 of the test specimen T into digital temperature information, an opposite surface side converter 402 that converts the analog temperature signal of a second measurement point SP2 measured by a target thermometer 72 on the opposite surface S2 of the test specimen T into digital temperature information, a comparator 403 that compares the temperature information converted by the contact surface side converter 401 and the temperature information converted by the opposite surface side converter 402 and outputs a duty cycle signal, a signal generator 404 that generates an adjustment signal, such as a PWM signal, according to the duty cycle signal output by the comparator 403, and a rectifier element 405 which is a triac that adjusts the output of the AC power supply based on the adjustment signal.

[0054] Furthermore, although not shown in the figures, as an example of another variation, the thermometer 7 of the evaluation device 1 includes a measuring instrument which is a radiation thermometer that captures infrared radiation emitted from the surface of the test specimen T to measure temperature, and a measuring drive mechanism. The measuring instrument is installed outside the furnace 2 and measures the surface temperature of the test specimen T placed inside the furnace 2 through a window (not shown) provided in the furnace 2. The measuring drive mechanism rotates the measuring instrument up and down (tilt) and left and right (pan) so that the surface of the test specimen T can be measured non-contact over a wide area. The measuring instrument is preferably a thermographic camera that can detect the temperature distribution on the surface of the test specimen T. In addition, the evaluation device 1 of this variation example includes a local heating means that locally heats areas with an uneven temperature distribution based on the surface temperature of the test specimen T measured by the thermometer 7 of this variation example. The local heating means consists of an infrared heater, a directional reflector that gives directionality to the infrared radiation generated from the infrared heater, and a heating drive mechanism that changes the position or orientation of the directional reflector. The infrared heater is preferably a halogen lamp, and the directional reflector is preferably a parabolic shape with a reflective material such as aluminum, which has high reflectivity. When the infrared radiation emitted by the infrared heater is isotropic, the directional reflector makes the infrared radiation semi-directional, and it is irradiated onto the test specimen T through the window. The infrared heater only needs to be able to heat a localized area of ​​the surface of the test specimen T installed in the furnace, and the infrared heater may be a quartz tube heater. The heating drive mechanism, controlled by the temperature change control unit 61, irradiates the surface of the test specimen T with infrared radiation from the directional reflector. At that time, the heating drive mechanism rotates up and down (tilt) and left and right (pan), similar to a measuring instrument, to change the position or irradiation direction of the directional reflector. In the evaluation device 1 of this example of change, the operation of the heating drive mechanism is controlled by the temperature change control unit 61, so that the thermometer 7 scans the surface of the test specimen T to measure the temperature distribution, and the local heating means can heat the surface of the test specimen T to a uniform temperature.

[0055] As shown in Figure 10, the evaluation apparatus 1 according to the present invention further comprises a fluid supply source 91, a fluid flow path 92, a fluid control mechanism 93, a power supply device 94, a fluid processing mechanism 95, and a control device 96. The fluid supply source 91 supplies fluids used in the furnace 2 and the test specimen T, such as a supply fluid to operate the test specimen T and a cooling fluid to lower the temperature of the test specimen T. The fluids are, but are not limited to, inert gases such as nitrogen gas, gases such as air and water vapor, liquids such as water, and gas-liquid mixtures obtained by mixing these. The fluid flow path 92 introduces the fluid supplied from the fluid supply source 91 to each mechanism and / or discharges the fluid that has been used in the test specimen T and the furnace 2. The fluid control mechanism 93 includes, for example, a mass flow controller or a flow control valve, and adjusts the fluid flowing to the test specimen T and / or the furnace 2 via the fluid flow path 92 to a predetermined flow rate. The power supply unit 94 supplies power for the furnace 2, the first heater 3, the second heater 5, the control unit 6, and the thermometer 7 to function. The fluid processing mechanism 95 processes the fluid used in the test specimen T and furnace 2 to a reusable state and recirculates it back to the test specimen T and furnace 2, and / or processes it so that it does not affect the environment and is safely discharged before being discharged outside the furnace. The control device 96 is an information processing device consisting of a storage unit such as RAM or ROM, an arithmetic processing unit such as a CPU, and a display unit such as a monitor screen. The storage unit stores programs for executing various information processing in the chemical reaction cell evaluation device 1 and data information acquired from each component of the evaluation device 1. The arithmetic processing unit executes various information processing in the evaluation device 1. The display unit displays the temperature distribution on the surface of the test specimen T, which is based on temperature information measured by the thermometer 7, and the status of the devices and mechanisms constituting the evaluation device 1, such as the temperature and flow rate of the fluid measured by the fluid control mechanism 93.

[0056] Although a hydrogen-related cell stack consisting of hydrogen-related cells was given as an example of a chemical reaction cell, catalysts are also included in chemical reaction cells. When a chemical reaction cell is a catalyst, the catalyst promotes the chemical reaction occurring in its surroundings; for example, a catalyst used for purifying automobile exhaust gases is an example of this.

[0057] Although embodiments of the present invention have been described above, the present invention is not limited in any way to these embodiments, and can be implemented in various forms without departing from the spirit of the invention.

[0058] 1 Evaluation device 2 Furnace 3 First heater 4 Base plate 5 Second heater 6 Control unit 7 Thermometer 8 Cooling mechanism 21 Inner wall 23 Bottom surface 29 Housing 40 Recess 41 Protrusion 42 Fluid flow path 43 Installation hole 61 Temperature change control unit 62 Temperature uniformization control unit 63 Temperature control control unit 71 Base plate contact surface thermometer 72 Target thermometer 81 Gas inlet 82 First gas outlet 83 Second gas outlet 101 Differentiator 102 Controller 103 Limiter 104 Amplifier 201 Calculator 202 Controller 203 Limiter 204 Amplifier 301 Contact surface side transducer 302 Opposite side transducer 303 Comparator 304 Signal generator 305 Rectifier element 401 Contact surface side transducer 402 Opposite surface side transducer 403 Comparator 404 Signal generator 405 Rectifier element 811 Inlet means 821 Gap 831 Discharge means 91 Fluid supply source 92 Fluid flow path 93 Fluid control mechanism 94 Power supply device 95 Fluid processing mechanism 96 Control device AC AC power supply C1 First control circuit C2 Second control circuit C3 Third control circuit C4 Fourth control circuit CF Forced convection DC DC power supply F1, F2 Cooling section FC Forced convection G Gas H1, H2, H3 Heating section PG Cooling fluid S1 Contact surface S2 Opposite surface SP1 First measurement point SP2 Second measurement point T Test specimen TP1, TP2, TP3 Region

Claims

1. An evaluation apparatus for a chemical reaction cell, comprising: a furnace covering the test specimen; a first heater provided on the inner wall of the furnace; a base plate provided on the bottom surface of the furnace to support the test specimen; a second heater provided on the base plate; and a control unit for controlling the outputs of the first heater and the second heater.

2. The chemical reaction cell evaluation apparatus according to claim 1, wherein the test specimen is a solid oxide fuel cell stack or a solid oxide electrolytic cell stack.

3. The chemical reaction cell evaluation apparatus according to claim 1 or 2, wherein the control unit includes a temperature change control unit for raising or lowering the temperature of the test specimen in the furnace, and a temperature uniformization control unit for uniformizing the surface temperature of the test specimen in the furnace.

4. The chemical reaction cell evaluation apparatus according to claim 3, wherein the temperature change control unit feeds back the temperature of the region in the test specimen where the temperature change per unit time during heating or cooling is smallest, as the temperature control target.

5. An evaluation apparatus for a chemical reaction cell according to any one of claims 1 to 4, further comprising: a base plate contact surface thermometer for measuring the temperature of the cell surface on the surface of the specimen that is in contact with the base plate; and a target thermometer for measuring the temperature of the cell surface on the surface of the specimen that is located on the opposite side of the cell surface in contact with the base plate, wherein the control unit controls the outputs of the first heater and the second heater so that the temperature of the base plate contact surface thermometer approaches the temperature of the target thermometer.

6. The chemical reaction cell evaluation apparatus according to any one of claims 1 to 5, wherein the control circuit of the control unit comprises a thyristor.

7. The chemical reaction cell evaluation apparatus according to any one of claims 1 to 6, wherein the second heater is a cartridge heater.

8. The chemical reaction cell evaluation apparatus according to any one of claims 1 to 7, wherein the base plate has a fluid channel connected to the test specimen for operating the test specimen, and the second heater is installed so as to sandwich the fluid channel of the base plate.

9. The chemical reaction cell evaluation apparatus according to any one of claims 1 to 8, wherein the furnace has a hood structure that can be raised and lowered, and the first heater is provided on the inner wall of the hood.

10. The chemical reaction cell evaluation apparatus according to any one of claims 1 to 9, wherein, as the first heater, an individual heater is provided in each of the three zones into which the inner wall portion is divided: upper, middle, and lower.

11. The chemical reaction cell evaluation apparatus according to any one of claims 1 to 10, wherein the furnace is provided with a gas inlet for circulating a cooling gas into the space inside the furnace, a gas outlet for circulating a cooling gas, and a fan for forced circulation.

12. A method for evaluating a chemical reaction cell that is a test specimen, comprising: a furnace having a first heater on its inner wall and a base plate supporting the test specimen on its bottom surface, the furnace covering the test specimen; a second heater on the base plate; a control unit for controlling the output of the first heater and the second heater; and the control unit controlling the first heater and the second heater to reduce unevenness in the surface temperature of the test specimen.

13. A program for an evaluation apparatus for a chemical reaction cell, comprising a furnace covering a test specimen, a first heater provided on the inner wall of the furnace, a base plate provided on the bottom surface of the furnace to support the test specimen, and a second heater provided on the base plate, wherein the program causes a computer to function as a control unit that controls the outputs of the first heater and the second heater.

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