JP2009037888A - Catalyst combustion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalyst combustion device capable of shortening the warm-up time of a fuel cell. <P>SOLUTION: The catalyst combustion device is equipped with a suction hole to which mixed gas of hydrogen and air is supplied, and a catalyst 216, which is installed at a downstream side of this suction hole and in which catalytic combustion of the mixed gas is carried out, and the fuel cell mounted on a fuel cell vehicle is warmed up by combustion heat in the catalyst 216. Moreover, the catalyst combustion device is equipped with a glow plug 214 which is installed on the downstream side of the suction hole, and which heats the catalyst 216, by burning the mixed gas, and a control part 28 to preheat the catalyst 216 by controlling the glow plug 214, when catalytic combustion of the mixed gas is catalyst-combusted by the catalyst 216. The control part 28 is equipped with an ignition determining part 283 for determining the completion of ignition of the catalyst 216, and an ignition device control part 282 to heat the catalyst 216 by controlling the glow plug 214, until the ignition of the catalyst is determined as being completed by the ignition determining part 283. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a catalytic combustion apparatus. Specifically, the present invention relates to a catalytic combustion apparatus for warming up a fuel cell mounted on a fuel cell vehicle.

  In recent years, fuel cell systems have attracted attention as a new power source for automobiles. The fuel cell system includes, for example, a fuel cell that generates power by chemically reacting a reaction gas, a reaction gas supply device that supplies the reaction gas to the fuel cell via a reaction gas flow path, and a control that controls the reaction gas supply device. An apparatus.

  The fuel cell has, for example, a stack structure in which several tens to several hundreds of cells are stacked. Here, each cell is configured by sandwiching a membrane electrode structure (MEA) between a pair of separators. The membrane electrode structure includes two electrodes, an anode electrode (anode) and a cathode electrode (cathode), and these electrodes. And a solid polymer electrolyte membrane sandwiched between the two.

  When hydrogen gas as a reaction gas is supplied to the anode electrode of the fuel cell and air containing oxygen as a reaction gas is supplied to the cathode electrode, power is generated by an electrochemical reaction. Since only harmless water is generated at the time of power generation, fuel cells are attracting attention from the viewpoint of environmental impact and utilization efficiency.

By the way, in a low-temperature environment such as below freezing point, the progress of the electrochemical reaction of the fuel cell is delayed and the power generation amount is reduced. For this reason, a fuel cell warm-up device that warms the fuel cell to a temperature preferable for power generation has been proposed (see Patent Document 1). In this warm-up device for a fuel cell, a catalytic combustion device for combusting a mixed gas of air and hydrogen gas is provided on a circulation channel of a heat transfer fluid that can exchange heat with the fuel cell. The heat transfer fluid is heated by heat exchange, and the fuel cell can be heated by circulating the heat transfer fluid.
JP-A-2005-251431

  However, when hydrogen gas is combusted in the catalytic combustion apparatus as described above, water vapor is generated by catalytic combustion, and this water vapor may adhere to the surface of the catalyst. In addition, the water condensed in the heat exchanger when the warming-up device is stopped becomes water vapor when the warming-up device is started, and this water vapor may adhere to the surface of the catalyst.

  Furthermore, when the piping through which the gas discharged from the catalytic combustion device flows and the piping through which the gas discharged from the fuel cell are connected, water vapor generated by the reaction in the fuel cell is passed through the piping through the catalyst. It may adhere to the surface.

  As described above, when the warm-up device is started in a state where water or water vapor is attached to the surface of the catalyst, even if the mixed gas is supplied to the catalytic combustion device, the combustion reaction is inhibited by water or water vapor. For this reason, the combustion reaction in the catalyst may become unstable, or it may take time until the combustion reaction starts, and it may take time to warm up the fuel cell to a predetermined temperature.

  An object of the present invention is to provide a catalytic combustion apparatus that can shorten the warm-up time of a fuel cell.

  A catalytic combustion apparatus (for example, a catalytic combustion apparatus 20 described later) of the present invention includes a mixed gas supply section (for example, a suction hole 212 described later) to which a mixed gas of hydrogen and air is supplied, and a downstream of the mixed gas supply section. And a catalyst combustion section (for example, a catalyst 216 described later) that catalytically burns the mixed gas, and a fuel cell (for example, described later) mounted on a fuel cell vehicle with the combustion heat in the catalyst combustion section A catalytic combustion apparatus for warming up the fuel cell 10), provided at a downstream side of the mixed gas supply section, and an ignition apparatus (for example, a glow plug described later) that heats the catalytic combustion section by burning the mixed gas 214) and a control unit (for example, a control unit 28 described later) that controls the ignition device and preheats the catalytic combustion unit when the mixed gas is catalytically combusted in the catalytic combustion unit, The control unit The ignition device until an ignition determination unit (for example, an ignition determination unit 283 described later) that determines completion of ignition of the catalyst combustion unit and the ignition determination unit determine that the ignition of the catalyst combustion unit is completed. And an ignition device control unit (for example, an ignition device control unit 282 described later) for heating the catalytic combustion unit.

  According to this invention, an ignition device that burns the mixed gas and heats the catalytic combustion portion is provided downstream of the mixed gas supply portion, and further, a control portion that controls the ignition device and preheats the catalytic combustion portion is provided. It was. Thereby, for example, even when water or water vapor is attached to the surface of the catalyst combustion part or the catalyst combustion part is frozen, the catalyst combustion part is preheated by the ignition device, Can be quickly heated to a temperature at which the mixed gas can be combusted. Therefore, the time required for warming up the fuel cell of the fuel cell vehicle can be shortened.

  Further, an ignition determination unit that determines completion of ignition of the catalyst combustion unit, and an ignition that controls the ignition device and heats the catalyst combustion unit until it is determined by the ignition determination unit that ignition of the catalyst combustion unit is completed. And an apparatus control unit. As a result, it is possible to keep the use time of the ignition device to the minimum necessary, prevent consumption of unnecessary electric power in the ignition device, and promptly start catalytic combustion by the catalytic combustion unit.

  In this case, it is preferable that the control unit further includes a catalyst preheating determination unit (for example, a catalyst preheating determination unit 281 described later) that determines whether or not the catalyst combustion unit is preheated by the ignition device.

  According to the present invention, when it is not necessary to preheat the catalytic combustion portion by the ignition device, the ignition device is driven and unnecessary power is consumed, or it takes more time than necessary to preheat the catalytic combustion portion. Can be prevented.

  In this case, the catalyst preheating determination unit is based on a stop period (for example, a power generation stop period to be described later) from when the power generation by the fuel cell is stopped until it is started, and a temperature of the catalyst combustion unit immediately before the start. It is preferable to estimate an active state of the catalytic combustion unit and determine whether or not to preheat the catalytic combustion unit by the ignition device according to the estimated state.

  According to the present invention, the active state of the catalytic combustion unit is estimated based on the power generation stop period of the fuel cell and the temperature of the catalytic combustion unit immediately before startup, and the preheating of the catalytic combustion unit by the ignition device according to the active state Whether or not is necessary is determined. In this way, by determining the use of the ignition device based on the active state of the catalyst combustion unit, unnecessary power is consumed in the ignition device, or it takes more time than necessary to preheat the catalyst combustion unit. Can be prevented.

  In this case, the ignition device is a glow plug, and the control unit determines whether or not the temperature of the glow plug has reached the ignition temperature of the mixed gas (for example, an ignition temperature determination described later). 284) and when the catalytic combustion unit is heated by the ignition device, after the ignition temperature determination unit determines that the temperature of the glow plug has reached the ignition temperature of the mixed gas, It is preferable to further include a supply control unit (for example, a supply control unit 285 described later) that supplies the plug.

  According to the present invention, when preheating of the catalytic combustion unit is started by the glow plug, the ignition temperature determination unit determines whether or not the temperature of the glow plug has reached the ignition temperature of the mixed gas, and reaches the ignition temperature. After the determination is made, the mixed gas is supplied to the glow plug. Thus, when the temperature of the glow plug reaches the ignition temperature of the mixed gas, by starting the supply of the mixed gas, for example, compared with the case where the supply start timing of the mixed gas is controlled by a timer, the catalytic combustion The part can be preheated quickly. Therefore, the time required for warming up the fuel cell of the fuel cell vehicle can be shortened.

  Here, by using the glow plug as the ignition device, the temperature of the glow plug can be estimated from the resistance value based on, for example, the temperature resistance characteristic of the glow plug. Thereby, the temperature of the glow plug can be estimated without installing a temperature sensor. Further, by using a glow plug as the ignition device, it is possible to reduce the influence of noise and suppress power consumption as compared with the case where a spark plug or a heat transfer heater is used as the ignition device.

  According to the present invention, for example, even when water or water vapor is attached to the surface of the catalytic combustion part or the catalytic combustion part is frozen, by preheating the catalytic combustion part with the ignition device, The catalytic combustion section can be quickly heated to a temperature at which the mixed gas can be combusted. Therefore, the time required for warming up the fuel cell of the fuel cell vehicle can be shortened. Further, an ignition determination unit that determines completion of ignition of the catalyst combustion unit, and an ignition that controls the ignition device and heats the catalyst combustion unit until it is determined by the ignition determination unit that ignition of the catalyst combustion unit is completed. By providing the device control unit, it is possible to keep the use time of the ignition device to the minimum necessary, prevent consumption of unnecessary electric power in the ignition device, and quickly start catalytic combustion by the catalytic combustion unit. .

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram of a fuel cell system 1 including a catalytic combustion apparatus 20 according to an embodiment of the present invention. The fuel cell system 1 supplies hydrogen gas and air to the fuel cell 10, the catalytic combustion device 20 that warms up the fuel cell 10, the cooling system 30 that cools the fuel cell 10, and the fuel cell 10 and the catalytic combustion device 20. Supply device 40. The fuel cell system 1 is mounted on a fuel cell vehicle (not shown).

  The fuel cell 10 generates electricity by an electrochemical reaction when hydrogen gas is supplied to the anode electrode (anode) side and air containing oxygen is supplied to the cathode electrode (cathode) side.

  A refrigerant as a heat medium circulates between the fuel cell 10, the catalytic combustion device 20, and the cooling system 30 via the refrigerant flow path 25. The cooling system 30 cools the fuel cell 10 by circulating the refrigerant through the refrigerant flow path 25 and exchanging heat with the refrigerant to remove heat from the refrigerant. The catalytic combustion apparatus 20 includes a catalyst heater 27 (see FIG. 2 described later) and a control unit 28 (see FIG. 3 described later) for controlling the catalyst heater 27, and a catalytic reaction with a mixed gas of hydrogen gas and air. The fuel cell 10 is warmed up by generating heat and applying heat to the refrigerant by heat exchange. The configuration of the catalytic combustion apparatus 20 will be described in detail later with reference to FIGS.

  The refrigerant flow path 25 includes a first refrigerant flow path 251 from the catalytic combustion apparatus 20 to the fuel cell 10, a second refrigerant flow path 252 from the fuel cell 10 to the cooling system 30, and a catalytic combustion apparatus from the cooling system 30. And a third refrigerant flow path 253 reaching 20. The second refrigerant flow path 252 is provided with an outlet temperature sensor 254 that detects the temperature of the refrigerant discharged from the fuel cell 10 and flowing through the second refrigerant flow path 252.

  The supply device 40 includes a compressor 41, a hydrogen tank 42 that supplies hydrogen gas, and an exhaust gas treatment device 47.

  The compressor 41 supplies air, and is connected to the cathode electrode side of the fuel cell 10 and the catalytic combustion apparatus 20 via an air supply path 43. That is, the air supply path 43 distributes and supplies the air supplied from the compressor 41 to the fuel cell 10 and the catalytic combustion apparatus 20. The air supply path 43 includes a first supply path 431 that extends from the compressor 41 to the fuel cell 10 and a second supply path 432 that branches from the first supply path 431 and reaches the catalytic combustion apparatus 20. .

  In the second supply path 432, hydrogen gas is supplied from a hydrogen supply device 453 described later in the vicinity of the catalytic combustion device 20. The hydrogen gas supplied from the hydrogen supply device 453 is mixed with the air flowing through the second supply path 432 by the mixer 435 and supplied to the catalytic combustion device 20. Further, on the upstream side of the hydrogen supply device 453 in the second supply path 432, a butterfly valve 433 that adjusts the flow rate of air flowing through the second supply path 432, and the flow rate of air flowing through the second supply path 432 And an airflow sensor 434 for detecting the airflow.

  A first air discharge path 441 and a second air discharge path 442 leading to the exhaust gas treatment apparatus 47 are connected to the cathode electrode side of the fuel cell 10 and the catalytic combustion apparatus 20, respectively. That is, the first air discharge path 441 and the second air discharge path 442 collectively discharge the air used in the fuel cell 10 and the catalytic combustion apparatus 20. A pressure control valve 443 is provided in the first air discharge path 441.

  The exhaust gas processing device 47 processes air and hydrogen gas discharged from the fuel cell 10 and the catalytic combustion device 20. Specifically, a diluter that dilutes hydrogen gas discharged through a hydrogen discharge path (to be described later) with air discharged through the first air discharge path 441 and the second air discharge path 442, and the noise of the mixed gas. It is configured to include a silencer to reduce.

  The hydrogen tank 42 supplies hydrogen gas, and is connected to the anode electrode side of the fuel cell 10 and the catalytic combustion apparatus 20 via a hydrogen supply path 45. The hydrogen supply path 45 includes a first hydrogen supply path 451 extending from the hydrogen tank 42 to the fuel cell 10, and a second hydrogen supply path 452 branching from the first hydrogen supply path 451 and reaching the catalytic combustion apparatus 20. And having.

  The first hydrogen supply path 451 is provided with a first hydrogen cutoff valve 454, a first regulator 456, and an ejector 457. The first hydrogen cutoff valve 454 opens and closes the first hydrogen supply path 451. The first regulator 456 reduces the high-pressure hydrogen gas supplied from the hydrogen tank 42 to a predetermined pressure. The ejector 457 circulates the hydrogen gas by collecting the hydrogen gas discharged to the hydrogen discharge path 461 described later through the recirculation flow path 462 and supplying it again to the fuel cell 10.

  Further, a hydrogen discharge path 461 reaching the exhaust gas treatment device 47 is connected to the anode electrode side of the fuel cell 10. That is, the hydrogen discharge path 461 discharges the hydrogen gas used in the fuel cell 10. The hydrogen discharge path 461 is provided with a recirculation flow path 462 branched from the hydrogen discharge path 461, and the tip of the recirculation flow path 462 is connected to an ejector 457. In addition, a purge valve 463 that discharges the gas flowing through the recirculation flow path 462 is provided between the branch point of the hydrogen discharge path 461 and the recirculation flow path 462 and the exhaust gas treatment device 47.

  In the second hydrogen supply path 452, a second hydrogen cutoff valve 455, a second regulator 458, a pressure sensor 459, and a hydrogen supply device 453 are sequentially arranged from the hydrogen tank 42 side toward the catalytic combustion device 20. Is provided. The second hydrogen cutoff valve 455 opens and closes the second hydrogen supply path 452. The second regulator 458 reduces the high-pressure hydrogen gas supplied from the hydrogen tank 42 to a predetermined pressure. The pressure sensor 459 detects the pressure in the second hydrogen supply path 452. The hydrogen supply device 453 injects hydrogen gas into the second supply path 432 described above. As the hydrogen supply device 453, specifically, an injector, an ejector, or the like is used.

In the fuel cell system 1 as described above, the procedure for generating power by the fuel cell 10 is as follows.
That is, hydrogen gas is supplied from the hydrogen tank 42 to the anode side of the fuel cell 10 through the hydrogen supply path 45. Further, by driving the compressor 41, air is supplied to the cathode side of the fuel cell 10 via the air supply path 43.
The hydrogen gas and air supplied to the fuel cell 10 are supplied for power generation, and then flow from the fuel cell 10 into the hydrogen discharge path and the first air discharge path 441 together with residual water such as produced water on the anode side. These hydrogen gas and air are processed by the exhaust gas processing device 47 and discharged.

FIG. 2 is a cross-sectional view of the catalyst heater 27 provided in the catalytic combustion apparatus 20.
The catalyst heater 27 includes a combustor 210 and a heat exchanger 220 connected in series to the combustor 210 and disposed downstream.

  The combustor 210 includes a cylindrical combustor case 211, a catalyst 216 as a catalyst combustion unit provided inside the combustor case 211, a rectifying plate 215, and a glow plug 214 as an ignition device.

  The combustor case 211 is formed with a suction hole 212 as a mixed gas supply unit, and the above-described mixer 435 is connected to the suction hole 212, and a mixed gas of hydrogen gas and air mixed in the mixer 435. Is supplied to the suction hole 212. The mixed gas supplied to the suction hole 212 is introduced into the combustor case 211.

  The rectifying plate 215 is provided downstream of the suction hole 212 and rectifies the mixed gas and supplies it to the catalyst 216. The catalyst 216 is provided downstream of the rectifying plate 215, and generates heat by catalytic combustion of a mixed gas of hydrogen gas and air. The glow plug 214 is provided between the rectifying plate 215 and the catalyst 216, and heats the catalyst 216 by burning a mixed gas of hydrogen gas and air. The combustor 210 is provided with a catalyst temperature sensor 218 that detects the temperature of the catalyst 216.

  The heat exchanger 220 includes a cylindrical heat exchanger case 221, a heat exchange channel 226 disposed along the inner wall of the heat exchanger case 221, and a staying part 225 surrounded by the heat exchange channel 226. And have.

  The heat exchange channel 226 is connected to the above-described third refrigerant channel 253 via the refrigerant inflow portion 227 and is connected to the above-described first refrigerant channel 251 via the refrigerant outflow portion 228. As a result, the refrigerant flows through the heat exchange channel 226. The gas discharged from the combustor 210 stays in the staying part 225. The staying portion 225 is provided with an exhaust hole 222 through which the staying gas is discharged. The second air discharge path 442 is connected to the exhaust hole 222.

  The gas heated by the catalytic combustion in the catalyst 216 is discharged from the combustor 210 to the heat exchanger 220. The gas discharged to the heat exchanger 220 stays in the staying part 225, and exchanges heat with the refrigerant circulating in the heat exchange channel 226 surrounding the staying part 225.

FIG. 3 is a block diagram of the control unit 28 provided in the catalytic combustion apparatus 20.
The control unit 28 includes a catalyst preheating determination unit 281, an ignition device control unit 282, an ignition determination unit 283, an ignition temperature determination unit 284, and a supply control unit 285, and the catalyst 216 performs catalytic combustion of the mixed gas. When the mixed gas is catalytically combusted by the catalyst 216, the glow plug 214 can be controlled to preheat the catalyst 216.

  The catalyst preheating determination unit 281 determines whether or not the catalyst 216 is preheated by the glow plug 214. The catalyst preheating determination unit 281 includes a timer (not shown) that measures a stop period from when power generation by the fuel cell 10 is stopped to when it is started. The catalyst preheating determination unit 281 estimates the active state of the catalyst 216 based on the stop period measured by the timer and the temperature of the catalyst 216 just before the activation detected by the catalyst temperature sensor 218, and this estimated Whether or not to preheat the catalyst 216 by the glow plug 214 is determined according to the state.

  The ignition device control unit 282 controls the energization amount of the glow plug 214 to heat the glow plug to a predetermined temperature. For example, when the catalyst 216 is preheated by the glow plug 214, the ignition device control unit 282 energizes the glow plug 214 until the ignition determination unit 283 determines that the ignition of the catalyst 216 is completed. 216 is heated.

  The ignition determination unit 283 determines completion of ignition of the catalyst 216 based on the temperature of the catalyst 216 detected by the catalyst temperature sensor 218. More specifically, the ignition determination unit 283 determines whether or not the ignition of the catalyst 216 has been completed by determining whether or not the temperature of the catalyst 216 has reached a predetermined ignition determination temperature. The ignition determination temperature is, for example, 50 ° C., but is not limited thereto.

  The ignition temperature determination unit 284 determines whether or not the temperature of the glow plug 214 has reached a predetermined ignition temperature of the mixed gas when the glow plug 214 preheats the catalyst 216. Specifically, the ignition temperature determination unit 284 detects the resistance value of the glow plug 214, and calculates the temperature of the glow plug 214 from the detected resistance value based on the temperature resistance characteristic of the glow plug 214.

  The supply control unit 285 controls the opening degree of the butterfly valve 433 and the hydrogen gas supply amount of the hydrogen supply device 453, and controls the flow rate of the mixed gas supplied to the catalyst heater 27 and the concentration of hydrogen gas in the mixed gas. adjust. When the supply control unit 285 heats the catalyst 216 by the glow plug 214, after the ignition temperature determination unit 284 determines that the temperature of the glow plug 214 has reached the ignition temperature of the mixed gas, 214.

The operation of the catalytic combustion apparatus 20 will be described with reference to the flowchart of FIG.
FIG. 4 is a flowchart showing a procedure of warm-up operation processing of the fuel cell 10 by the catalytic combustion device 20. This warm-up operation process is started, for example, in response to the ignition being turned on.

  In ST1, a power generation stop period of the fuel cell is detected, and the process proceeds to ST2. In ST2, the temperature of the catalyst of the catalyst heater is detected, and the process proceeds to ST3. In ST3, based on the detected power generation stop period and the catalyst temperature, the map shown in FIG. 5 is searched to determine the active state of the catalyst, and it is determined whether or not the catalyst needs to be preheated using a glow plug. To do. If this determination is YES, the process moves to ST4, and if it is NO, the process moves to ST9.

FIG. 5 is a diagram showing a control map relating to the active state of the catalyst.
The active state of the catalyst is determined based on a predetermined threshold value ts related to the power generation stop period t and a predetermined threshold value Ts related to the catalyst temperature T. As shown in FIG. 5, it is determined that preheating of the catalyst using the glow plug is not necessary only when the power generation stop period is short-term (t ≦ ts) and the catalyst temperature is high (T> Ts). Is determined to require preheating of the catalyst using a glow plug.

  In ST4, the glow plug is energized, heating of the glow plug is started, and the process proceeds to ST5. In ST5, it is determined whether or not the temperature of the glow plug has reached a predetermined ignition temperature of the mixed gas. If this determination is YES, the process moves to ST6, and if it is NO, the process moves to ST5. In ST6, the flow rate and concentration of the mixed gas are adjusted based on the control map shown in FIG. 6, and the supply of the mixed gas is started.

FIG. 6 is a diagram showing a control map related to the mixed gas flow rate and the mixed gas concentration.
When the glow plug is not used, the flow rate of the mixed gas is set to a preset normal flow rate, and the concentration of the mixed gas is set to a preset normal concentration. When a glow plug is used, the flow rate of the mixed gas is set to a low flow rate lower than the normal flow rate, and the concentration of the mixed gas is set to a high concentration higher than the normal concentration.

  In ST7, it is determined whether or not the temperature of the catalyst is equal to or higher than a predetermined ignition determination temperature. If this determination is YES, the process moves to ST8, and if it is NO, the process moves to ST7. In ST8, energization of the glow plug is terminated, and the process proceeds to ST11.

  In ST9, the flow rate and concentration of the mixed gas are adjusted based on the control map shown in FIG. 6, and the supply of the mixed gas is started. In ST10, it is determined whether or not the temperature of the catalyst is equal to or higher than a predetermined ignition determination temperature. If this determination is YES, the process moves to ST11, and if it is NO, the process moves to ST10.

  In ST11, when it is determined that the temperature of the catalyst is equal to or higher than the predetermined set temperature, the flow rate and concentration of the mixed gas are readjusted, and the process proceeds to ST12. In ST12, it is determined whether or not the temperature of the fuel cell is equal to or higher than a predetermined value. Specifically, it is determined whether or not the refrigerant temperature detected by the outlet temperature sensor 254 (see FIG. 1) is equal to or higher than a predetermined value. If this determination is YES, the process proceeds to ST13, and if NO, the process proceeds to ST12. In ST13, the supply of the mixed gas is terminated, and the warm-up operation process is terminated.

  FIG. 7 is a time chart of the warm-up operation process by the catalytic combustion apparatus 20. Specifically, FIG. 7 is a time chart showing an example of warm-up operation processing when the catalyst is preheated by a glow plug.

  At time t0, the ignition is turned on and the warm-up operation process is started. The outlet water temperature of the fuel cell 10 at this time t0, that is, the temperature detected by the outlet temperature sensor 254 is a first predetermined temperature, and this first predetermined temperature is, for example, about −40 ° C. to −20 ° C. .

  At time t1, energization of the glow plug 214 is started (ST4 in FIG. 4), and at time t2, it is determined that the temperature of the glow plug 214 has reached the ignition temperature (ST5 in FIG. 4), and the hydrogen supply device 453. Thus, the hydrogen gas is supplied to the air, and the supply of the mixed gas is started (ST6 in FIG. 4).

  At time t3, it is determined that the catalyst temperature has reached the ignition determination temperature (ST7 in FIG. 4), energization of the glow plug is completed (ST8 in FIG. 4), and the preheating of the catalyst 216 is completed. Here, according to the completion of preheating of the catalyst 216, the flow rate and concentration of the mixed gas are readjusted (ST11 in FIG. 4). Specifically, the rotational speed of the compressor 41 is increased to increase the air flow rate, and the hydrogen gas supply amount by the hydrogen supply device 453 is increased to increase the hydrogen gas flow rate, whereby the catalyst 216 is increased. Starts catalytic combustion at. Then, the catalyst temperature rises rapidly.

At time t4, the catalyst temperature reaches the steady operation temperature, and the outlet water temperature of the fuel cell 10 starts to rise. The steady operation temperature is assumed to be about 700 ° C., for example.
At time t5, it is determined that the outlet water temperature of the fuel cell 10 has reached the second predetermined temperature (ST12 in FIG. 4), the hydrogen supply device 453 is turned off, and the supply of the mixed gas is terminated (ST13 in FIG. 4). ), The fuel cell warm-up process is terminated. The second predetermined temperature is, for example, about 0 ° C. to 20 ° C.

According to this embodiment, there are the following effects.
(1) A glow plug 214 that burns the mixed gas and heats the catalyst 216 is provided on the downstream side of the suction hole 212, and a control unit 28 that preheats the catalyst 216 by controlling the glow plug 214 is provided. Thereby, for example, even when water or water vapor is attached to the surface of the catalyst 216 or the catalyst 216 is frozen, the catalyst 216 is mixed by preheating the catalyst 216 with the glow plug 214. The gas can be quickly heated to a combustible temperature. Therefore, the time required for warming up the fuel cell of the fuel cell vehicle can be shortened.

  Further, an ignition determination unit 283 that determines completion of ignition of the catalyst 216, and ignition that controls the glow plug 214 to heat the catalyst 216 until the ignition determination unit 283 determines that ignition of the catalyst 216 is completed. An apparatus control unit 282 is provided. As a result, it is possible to keep the use time of the glow plug 214 to the minimum necessary, prevent consumption of unnecessary electric power in the glow plug 214, and promptly start catalytic combustion by the catalyst 216.

FIG. 8 is a diagram showing the relationship between the temperature of the catalyst 216 and the passage of time.
In FIG. 8, the dotted line indicates the case where the catalyst 216 is preheated using the glow plug 214, and the broken line indicates the case where the catalyst 216 is preheated without using the glow plug 214. Here, the catalyst temperature T1 is a set temperature.

When the operation is started at time t0, when the glow plug 214 is used, the temperature of the catalyst 216 quickly rises and reaches the set temperature at time t1. On the other hand, when the glow plug 214 is not used, the temperature of the catalyst 216 does not rise easily, and reaches the set temperature at time t2 later than time t1.
In this way, the time when the catalyst 216 reaches the set temperature can be shortened by burning the mixed gas with the glow plug 214 and heating the catalyst 216 with the heat.

  (2) By providing the ignition device control unit 282, when the pre-heating of the catalyst 216 by the glow plug 214 is not necessary, the glow plug 214 is driven and unnecessary power is consumed or necessary for pre-heating the catalyst 216. It can prevent taking more time.

  (3) The active state of the catalyst 216 is estimated by the catalyst preheating determination unit 281 based on the power generation stop period of the fuel cell 10 and the temperature of the catalyst 216 immediately before starting, and the catalyst by the glow plug 214 according to this active state It is determined whether 216 preheating is required. As described above, by determining the use of the glow plug 214 based on the active state of the catalyst 216, unnecessary power is consumed in the glow plug 214, or it takes more time than necessary to preheat the catalyst 216. Can be prevented.

  (4) When the catalyst 216 is preheated by the glow plug 214, the ignition temperature determination unit 284 determines whether or not the temperature of the glow plug 214 has reached the ignition temperature of the mixed gas, and has reached the ignition temperature. After that, the mixed gas is supplied to the glow plug 214.

  Further, by using the glow plug 214, the temperature of the glow plug 214 can be estimated from the resistance value based on the temperature resistance characteristic of the glow plug 214, for example. Thereby, the temperature of the glow plug 214 can be estimated without installing a temperature sensor. In addition, by using the glow plug 214 as the ignition device, it is possible to reduce the influence of noise and suppress power consumption as compared with the case where a spark plug, a heat transfer heater, or the like is used as the ignition device.

FIG. 9 is a diagram showing the relationship between the catalyst temperature and the passage of time when the catalyst 216 is preheated by the glow plug 214.
In FIG. 9, the dotted line indicates the case where the ignition temperature of the glow plug 214 is determined by reading the resistance value of the glow plug 214 and the supply of the mixed gas is started, and the broken line indicates the supply of the mixed gas by timer control. Shows when started. Further, the catalyst temperature T1 is a set temperature.

  Operation starts at time t0 and energization of the glow plug 214 is started. When the ignition temperature is determined by reading the resistance value of the glow plug 214, when the glow plug 214 reaches the ignition temperature at the time t1, the supply of the mixed gas is immediately started, the preheating of the catalyst 216 is started, and the time t2 The catalyst temperature reaches the set temperature at.

  On the other hand, when the supply of the mixed gas is started by the timer control, the supply of the mixed gas is not started even when the glow plug 214 reaches the ignition temperature at time t1, and the mixed gas is not supplied after the set time has elapsed at time t3. Supply is started. Thereafter, preheating of the catalyst 216 is started, and the catalyst temperature reaches the set temperature at time t4.

  Thus, by starting the supply of the mixed gas when the temperature of the glow plug 214 reaches the ignition temperature of the mixed gas, the preheating of the catalyst 216 can be started more quickly than in the case of timer control. Therefore, the time required for warming up the fuel cell of the fuel cell vehicle can be shortened.

  It should be noted that the present invention is not limited to the above-described embodiment, but includes modifications and improvements as long as the object of the present invention can be achieved.

  In the above embodiment, the ignition determination unit 283 determines completion of ignition of the catalyst 216 based on the temperature of the catalyst 216, but the present invention is not limited to this. For example, completion of catalyst ignition may be determined by time. That is, it is possible to set in advance a time that the ignition of the catalyst is considered to be completed, and when this set time has elapsed, it may be determined that the ignition of the catalyst has been completed.

  In the above embodiment, the glow plug 214 is provided as the ignition device, but the present invention is not limited to this. For example, an electric heating catalyst (EHC) or a spark plug may be provided as the ignition device.

1 is a block diagram of a fuel cell system according to an embodiment of the present invention. It is sectional drawing of the catalyst heater of the catalytic combustion apparatus which concerns on the said embodiment. It is a block diagram of the control part of the catalytic combustion apparatus which concerns on the said embodiment. It is a flowchart which shows the procedure of the warm-up operation process of the fuel cell by the catalytic combustion apparatus which concerns on the said embodiment. It is a figure which shows the control map of the catalytic combustion apparatus which concerns on the said embodiment. It is a figure which shows the control map of the catalytic combustion apparatus which concerns on the said embodiment. It is a time chart of the warm-up operation process by the catalyst combustion apparatus which concerns on the said embodiment. The figure which shows the relationship between the temperature of the catalyst which concerns on the said embodiment, and time passage. It is a figure which shows the relationship between catalyst temperature and time passage when a catalyst is preheated with the glow plug which concerns on the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel cell system 10 Fuel cell 20 Catalytic combustion apparatus (catalytic combustion apparatus)
27 Catalyst heater 212 Suction hole (mixed gas supply part)
216 Catalyst (Catalytic combustion section)
214 Glow plug (ignition device)
28 Control unit (control unit)
281 Catalyst Preheating Determination Unit (Catalyst Preheating Determination Unit)
282 Ignition device control unit (ignition device control unit)
283 Ignition determination unit (ignition determination unit)
284 Ignition temperature judgment part (ignition temperature judgment part)
285 Supply control unit (supply control unit)

Claims (4)

A mixed gas supply unit to which a mixed gas of hydrogen and air is supplied;
A catalytic combustion section provided on the downstream side of the mixed gas supply section and catalytically burning the mixed gas, wherein the combustion heat in the catalytic combustion section is used to warm up the fuel cell mounted on the fuel cell vehicle. A device,
An ignition device that is provided on the downstream side of the mixed gas supply unit and that heats the catalytic combustion unit by burning the mixed gas;
When catalytically burning the mixed gas in the catalytic combustion unit, the control unit for controlling the ignition device to preheat the catalytic combustion unit,
The controller is
An ignition determination unit for determining completion of ignition of the catalyst combustion unit;
An ignition device control unit that controls the ignition device to heat the catalyst combustion unit until it is determined by the ignition determination unit that the ignition of the catalyst combustion unit is completed. apparatus. The controller is
The catalytic combustion apparatus according to claim 1, further comprising a catalyst preheating determination unit that determines whether or not the catalyst combustion unit is preheated by the ignition device.   The catalyst preheating determination unit estimates an active state of the catalyst combustion unit based on a stop period from when power generation by the fuel cell is stopped until it is started and a temperature of the catalyst combustion unit immediately before startup, and the estimation The catalytic combustion apparatus according to claim 2, wherein it is determined whether or not to preheat the catalytic combustion section by the ignition device in accordance with a state that has been achieved. The ignition device is a glow plug;
The controller is
An ignition temperature determination unit for determining whether or not the temperature of the glow plug has reached the ignition temperature of the mixed gas;
When heating the catalytic combustion unit by the ignition device, supply of supplying the mixed gas to the glow plug after the ignition temperature determining unit determines that the temperature of the glow plug has reached the ignition temperature of the mixed gas The catalytic combustion apparatus according to claim 1, further comprising a control unit.

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