JP4821120B2 - Fuel cell system and operation method thereof - Google Patents

Description

The present invention relates to a fuel cell system and an operation method thereof .

  Patent Document 1 discloses a fuel cell system to which a conventional polymer electrolyte fuel cell (PEFC) is applied.

  A fuel cell applied to this fuel cell system generates power by supplying fuel gas and air. In this fuel cell, a solid polymer membrane that is an electrolyte membrane made of an ion exchange resin is sandwiched between a fuel electrode (also referred to as an anode electrode or a hydrogen electrode) and an air electrode (also referred to as a cathode electrode or an oxygen electrode). It has a fuel chamber for supplying fuel gas to the fuel electrode

In such a configuration of the fuel cell system, when the power generation startup of the fuel cell, and the air was replaced by the fuel chamber unevenly distributed in the fuel chamber when stopping the fuel gas supply has been started to fuel chamber, the surface of the fuel electrode There may be a situation in which the reaction distribution becomes uneven. When such a situation occurs, a local abnormal power generation state occurs in the fuel chamber, and the fuel cell deteriorates.

  For this reason, this fuel cell system has a power generation starting means capable of preventing the deterioration of the fuel cell at the time of power generation startup. The power generation starting means can replace the air in the fuel chamber by pressurized supply of fuel gas when the fuel cell starts power generation. Specifically, the power generation starting means supplies a fuel gas having a higher supply pressure than that during normal power generation to the fuel chamber after opening a discharge passage communicating with the fuel chamber when starting power generation of the fuel cell. The air in the fuel chamber can be rapidly discharged through the discharge passage while being replaced with the fuel gas. Thus, this fuel cell system can prevent deterioration of the fuel cell at the time of starting power generation.

  Also, in this fuel cell system, when the fuel cell power generation is stopped, the chemical reaction between the fuel gas and air continues in the fuel chamber to prevent deterioration of the fuel cell. The fuel gas introduced into the room and filling the fuel room is replaced with air. However, in this case as well, when the power generation is started, there is a possibility that the fuel gas and air are unevenly distributed in the fuel chamber and the reaction distribution becomes uneven on the surface of the fuel electrode. Even when such a situation occurs, a local abnormal power generation state occurs in the fuel chamber, and the fuel cell deteriorates.

  For this reason, Patent Document 2 discloses a fuel cell system having a power generation stopping means capable of preventing the deterioration of the fuel cell described above when power generation is stopped. Since the configuration other than the power generation stopping means is substantially the same as that of Patent Document 1, description thereof is omitted.

  In this fuel cell system, the power generation stop means is configured to forcibly discharge the fuel gas in the fuel chamber when the fuel cell power generation is stopped to reduce the pressure, and then introduce and replace the outside air. Specifically, the power generation stop means first shuts off the fuel gas supply path and opens the discharge path communicating with the fuel chamber when power generation of the fuel cell is stopped. Next, the fuel gas in the fuel chamber is sucked with a pump or the like and is forcibly discharged from the discharge path to be in a decompressed state. After that, by supplying external air into the fuel chamber from the outside air passage communicating with the fuel chamber, the fuel chamber can be replaced with air without the fuel gas and air being unevenly distributed in the fuel chamber. Thus, this fuel cell system can prevent deterioration of the fuel cell when power generation is started and stopped.

On the other hand, Patent Document 3, a fuel cell system including a Capacity data as storage means provided in parallel with the fuel cell is disclosed.

  This fuel cell system is mounted on, for example, an automobile, and a fuel cell and a capacitor are connected in parallel to an external load device which is an auxiliary machine such as a drive motor and fuel supply means.

  The control system is capable of switching control so that one or both of the fuel cell and the capacitor supply power to the external load device. Further, the control system can be controlled to charge the capacitor by the electric power of the fuel cell or by the regenerative energy of the external load device.

  The fuel cell system of Patent Document 2 having such a configuration can supply power to the external load device while switching between the fuel cell and the capacitor in accordance with the traveling state of the automobile.

  Specifically, for example, when the accelerator is depressed during steady operation of the vehicle, the capacitor dominantly supplies power at the initial stage of acceleration, and the fuel cell dominantly supplies power at the end of acceleration. Return to steady state. Thus, a smooth acceleration response can be realized.

  Also, since the fuel cell cannot supply power at the start of the automobile, the capacitor supplies power to drive power generation starting means such as solenoid valves and auxiliaries, and the fuel cell starts power generation with a predetermined power generation start operation. Let Furthermore, when the vehicle is stopped, the fuel cell is disconnected from the external load device, and then the capacitor supplies power to drive power generation stop means such as a solenoid valve and auxiliary machinery, and the fuel cell is stopped in a predetermined power generation stoppage. To stop power generation. When the automobile is decelerated, the regenerative energy of the drive motor is supplied to the capacitor to charge the capacitor.

  Thus, this fuel cell system achieves smooth driving of the automobile and also improves energy efficiency.

  In this fuel cell system, the control system measures the voltage between both terminals of the capacitor and the voltage between both terminals when the fuel cell is opened. For this reason, in this fuel cell system, when the difference between the voltage between both terminals of the capacitor and the voltage between both terminals when the fuel cell is opened exceeds the threshold value, the switching between the fuel cell and the capacitor is chopped. In addition, an excessive current is prevented from flowing from the fuel cell to the capacitor.

JP 2004-139984 A JP 2003-109630 A JP 2003-197229 A

  However, in the fuel cell system including the power generation starting unit and the power generation stopping unit as in Patent Documents 1 and 2 and the power storage unit as in Patent Document 3, the stored power of the power storage unit is excessively consumed. In addition, a situation may occur in which the amount of power stored in the power storage means is significantly reduced.

  For example, in spite of the malfunction of the fuel cell and the shift to the abnormal stop operation, there is a problem such as a delay in the transmission / reception of the abnormal stop signal between the control command system of the vehicle and the control means of the fuel cell system. When this occurs, there is a risk that the vehicle will continue to run only with the stored power of the power storage means. As a result, a situation may occur in which the stored power of the power storage means is excessively consumed while the automobile is traveling, and the amount of stored power is significantly reduced.

  In addition, during normal power generation of the fuel cell, even when the high load state to the fuel cell continues and the power output cannot be maintained by the fuel cell itself, the automobile is provided in parallel with the fuel cell for the control of the parallel circuit. There is a risk of continuing traveling depending on the stored power of the power storage means. As a result, the same situation as described above may occur.

  Furthermore, even when a problem such as defective charging occurs in the power storage means, only the stored power of the power storage means is consumed, and the same situation as described above may occur.

  In this way, if the stored power of the power storage means is excessively consumed and the amount of power storage is greatly reduced when the fuel cell power generation is started or stopped, the power generation means or the power generation start means is stopped. The power supply to the means is interrupted or becomes insufficient, and the electromagnetic valves and auxiliary machines constituting the power generation starting means or the power generation stopping means cannot be driven normally. As a result, the fuel cell system cannot complete the remaining processes of the power generation start operation and the power generation stop operation, and the fuel cell is deteriorated for the above-described reason, thereby reducing the durability of the fuel cell. Will end up.

  In this regard, the fuel cell system disclosed in Patent Document 3 only detects the voltage between the two terminals of the power storage means, thereby merely preventing an excessive current from flowing from the fuel cell to the power storage means. It is impossible to prevent the deterioration of the fuel cell due to the shortage of the amount of electricity stored in the electricity storage means.

  The present invention has been made in view of the above-described conventional situation, and an object to be solved is to provide a fuel cell system that is unlikely to cause a decrease in durability of the fuel cell due to deterioration of the fuel cell.

The fuel cell system according to the present invention, the solid polymer film is sandwiched between a fuel electrode and an air electrode, and the said fuel gas and air is supplied with a fuel chamber for supplying the fuel gas to the fuel electrode A fuel cell that generates electricity,
Power storage means capable of storing power generated by the fuel cell or power supplied from an external load device;
Power generation starting means that is driven by the electric power stored in the power storage means and starts power generation of the fuel cell by a predetermined power generation start operation;
A power generation stop means that is driven by the power stored in the power storage means and stops the power generation of the fuel cell by a predetermined power generation stop operation;
Emits fuel determined to alarm signal the power storage amount storage amount required when及beauty power generation stop operation is not in the accumulating means is an abnormality in the absence in the accumulating means occurs necessary for power generation startup operation of the battery Control means ,
The power generation starting means replaces the air in the fuel chamber with the pressurized supply of the fuel gas at the time of power generation start of the fuel cell,
The power generation stop means, when the power generation stop of the fuel cell, after the reduced pressure state is forcibly discharged fuel chamber of the fuel gas, characterized in der Rukoto those that substitute by introducing outside air .

  Specifically, the control unit measures the amount of power stored in the power storage unit based on, for example, a voltage value or a current value between both terminals of the power storage unit. Further, the control means has a power generation activation time determination routine and / or a normal power generation time determination routine. The power generation start time determination routine determines that an abnormality has occurred when the power storage means does not have the power storage amount required for the power generation start operation of the fuel cell, and the normal power generation start determination routine stores the power storage amount required for the power generation stop operation. When it is not in the means, it is determined that an abnormality has occurred. And a control means issues a warning signal, when it determines with it being abnormal. Hereinafter, the determination procedure will be described in detail.

  The power generation start-up determination routine first compares “measured power storage amount of power storage means” (w) with “power storage required for power generation start operation of fuel cell” (Ws1) at the time of power generation start of the fuel cell. When the power storage means (Ws1) required for the power generation start operation of the fuel cell is not in the power storage means (w <Ws1), it is determined that there is an abnormality. Thereby, the control means issues an alarm signal. As a result, the fuel cell system can recognize the abnormality and shift to necessary processing such as abnormal stop. For this reason, even if the power storage means does not have the amount of power required for the power generation start operation of the fuel cell, the power storage means runs out of power when the fuel cell starts power generation, and the predetermined power generation start operation cannot be completed. The situation can be avoided.

  On the other hand, if w ≧ Ws1, the power generation activation determination routine determines that the power storage means is not insufficient. As a result, the fuel cell system sequentially executes operations at the time of power generation startup of the fuel cell. For this reason, when the fuel cell is started to generate power, the amount of power stored in the power storage means is lost, and a situation in which a predetermined power generation start operation cannot be completed does not occur.

  In addition, the normal power generation determination routine includes “measured power storage amount of power storage means” (w) and “fuel cell power generation stoppage” continuously or periodically at relatively short intervals during normal power generation of the fuel cell. The power storage amount necessary for operation ”(Wc1) is compared, and if the power storage means does not have the power storage amount (Wc1) required for the power generation start operation of the fuel cell (w <Wc1), it is determined that there is an abnormality. Thereby, the control means issues an alarm signal. As a result, the fuel cell system can recognize the abnormality and shift to necessary processing such as abnormal stop. For this reason, even if the power storage means does not have the amount of electricity necessary for the power generation stop operation of the fuel cell, the power storage amount of the power storage means disappears when the power generation of the fuel cell is stopped, and the predetermined power generation start operation cannot be completed. The situation can be avoided.

  On the other hand, if w ≧ Wc1, the normal power generation determination routine determines that the power storage means is not short of power storage. As a result, the fuel cell system continues the operation of the fuel cell during normal power generation as it is. For this reason, even if the fuel cell has to stop power generation due to some troubles under this situation, when the fuel cell power generation stops, all the stored power of the power storage means is consumed and the amount of power storage is lost. It does not occur.

  For this reason, in this fuel cell system, when power generation of the fuel cell is started or stopped, power supply from the power storage means to the power generation start means or the power generation stop means is interrupted or becomes insufficient. The situation in which the stopping means cannot be driven normally is prevented, and as a result, once the operation is shifted to the power generation start operation or the power generation stop operation, the processing can be completed.

  For this reason, this fuel cell system can suppress deterioration of the fuel cell due to the inability to complete a predetermined power generation start operation and power generation stop operation.

  Therefore, the fuel cell system of the present invention is unlikely to cause a decrease in durability of the fuel cell due to deterioration of the fuel cell.

  In addition, about said Ws1 and Wc1, it is preferable that the considerable margin is added considering the measurement error of the electrical storage amount of an electrical storage means, and the dispersion | variation by various driving | running conditions.

In this case, as described above, the power generation starting means further effectively prevents deterioration at the time of power generation start of the fuel cell, and the power generation stop means further reduces deterioration at the time of power generation stop of the fuel cell as described above. It is an effective prevention. Therefore, fuel cell systems, can be further enjoyed the effects of the present invention.

In fuel cell system, the control means, when having issued the alarm signal is intended to stop the fuel cell at a predetermined abnormal stop operation.

In this case, fuel cell system, it is possible to reliably abnormal stop of the fuel cell, it is possible to enhance the safety of the fuel cell system more.

The present invention may also be a method for operating a fuel cell system. The method of operating a fuel cell system of the present invention, the solid polymer film is sandwiched between a fuel electrode and an air electrode, and the said fuel gas and air with a fuel chamber for supplying the fuel gas to the fuel electrode A fuel cell that is supplied and generates electricity;
Power storage means capable of storing power generated by the fuel cell or power supplied from an external load device ;
Power generation starting means that is driven by the electric power stored in the power storage means and starts power generation of the fuel cell by a predetermined power generation start operation;
In an operation method of a fuel cell system, comprising: a power generation stop unit that is driven by electric power stored in the power storage unit and stops the power generation of the fuel cell by a predetermined power generation stop operation .
The power generation starting means replaces the air in the fuel chamber with the pressurized supply of the fuel gas at the time of power generation start of the fuel cell,
The power generation stop means, when power generation of the fuel cell is stopped, forcibly exhausts the fuel gas in the fuel chamber to a reduced pressure state, and then introduces and replaces outside air.
Emits fuel determined to alarm signal the power storage amount storage amount required when及beauty power generation stop operation is not in the accumulating means is an abnormality in the absence in the accumulating means occurs necessary for power generation startup operation of the battery It is characterized by that.

  A first embodiment of the present invention will be described below with reference to the drawings.

  A fuel cell system 100 of Example 1 shown in FIG. 1 is one in which the polymer electrolyte fuel cell 1 shown in FIG. 2 is applied.

  In the fuel cell 1, the laminate 10 is sandwiched between two end plates 20a and 20b via current collectors and insulating plates (not shown). As shown in FIG. 3, the stacked body 10 is formed by sequentially stacking MEA (Membrane Electrode Assembly) 11 while being sandwiched between separators 12. The MEA 11 includes an electrolyte membrane 11a made of an ion exchange resin, a fuel electrode 11b made of carbon integrally formed on one surface of the electrolyte membrane 11a, and an air electrode made of carbon integrally formed on the other surface of the electrolyte membrane 11a. 11c. All the fuel electrodes 11b are electrically connected to one current collector plate, and all the air electrodes 11c are electrically connected to the other current collector plate. As shown in FIG. Each terminal 1a, 1b protrudes from the fuel cell 1.

  As shown in FIG. 3, a fuel chamber 12a is formed on the fuel electrode 11b side of each separator 12, and hydrogen gas, which is a fuel gas, is supplied to the fuel electrode 11b by the fuel chamber 12a. On the other hand, an air chamber 12b is formed on the air electrode 11c side of each separator 12, and air containing oxygen is supplied to the air electrode 11c by the air chamber 12b. The fuel chamber 12a is opened in the horizontal direction, and the air chamber 12b is opened in the vertical direction, which is a direction orthogonal to the fuel chamber 12a. In addition, only the fuel chamber 12a or the air chamber 12b is formed in the separator 12 of the both ends of the laminated body 10. FIG. Thus, each MEA 11 and the pair of separators 12 constitute individual fuel cell 10a. As shown in FIG. 2, all the fuel chambers 12a of each cell 10a communicate with a supply port 21a formed in one end plate 20a and a discharge port 21b formed in the other end plate 20b.

  As shown in FIG. 1, the fuel cell 1 is assembled with other components to constitute a fuel cell system 100.

  The following various components are connected to the supply port 21a and the discharge port 21b provided in the fuel chamber 12a of the fuel cell 1 to supply hydrogen gas into the fuel chamber 12a or from the fuel chamber 12a. It is possible to discharge hydrogen gas or replace the inside of the fuel chamber 12a with outside air.

  There is a hydrogen tank 50 on the most upstream side of the supply port 21a, and the hydrogen tank 50 is provided with pipes 51a, 51b, 51c arranged in parallel so as to join at the connection point A. The pipes 51a, 51b, 51c are respectively connected to the hydrogen source solenoid valves 60a, 60b, 60c, the primary pressure sensors 71a, 71b, 71c, and the hydrogen primary pressure regulators 61a, 61b, 61c from the hydrogen tank 50 side. Have.

  A pipe 52a is provided from the connection point A through the connection point B to the connection point C, and a pipe 52b is provided from the connection point B to the connection point C in parallel with the pipe 52a. The pipe 52 a has a secondary pressure sensor 72 upstream from the connection point B, and a hydrogen secondary pressure regulator 62 a downstream from the connection point B. The pipe 52b has a hydrogen starting electromagnetic valve 62b.

  A pipe 53 is provided from the connection point C to the connection point D. The pipe 53 has a hydrogen supply electromagnetic valve 63 and a tertiary pressure sensor 73 downstream thereof. The tertiary pressure sensor 73 can detect the pressure between the hydrogen supply electromagnetic valve 63 and the supply port 21a.

  A pipe 54 is provided from the connection point D to the supply port 21a. The pipe 54 has a relief valve 64 that is opened when the pressure in the pipe 54 rises excessively and releases the gas in the pipe 54 to the atmosphere.

  A pipe 56 is provided from the discharge port 21b to the connection point E. The pipe 56 has a drain tank 87 in which a level gauge 87a is built, and has a hydrogen pump 81 downstream thereof.

  A pipe 57 is provided from a drain tank 87 in the middle of the pipe 56 to a duct 91 described later via a connection point F. The pipe 57 has a hydrogen starting exhaust electromagnetic valve 67 upstream of the connection point F.

  A pipe 58 is provided from the connection point E to the connection point F on the downstream side of the hydrogen pump 81. The pipe 58 has a hydrogen stop exhaust electromagnetic valve 68.

  A pipe 59 is provided from the connection point E to the connection point D via the connection point G. The pipe 59 has a hydrogen circulation electromagnetic valve 69 between the connection point E and the connection point G.

  The connection point G is provided with a pipe 55 whose other end is open. The pipe 55 includes an outside air introduction electromagnetic valve 65 and a filter 55b attached to the open end.

  The pipes 51a, 51b, 51c, 52a, 52b, 53, and 54 are supply paths. And piping 51a, 51b, 51c, 52a, 52b, hydrogen source solenoid valves 60a, 60b, 60c, primary pressure sensors 71a, 71b, 71c, hydrogen primary pressure regulator 61a, which are part of the supply path, 61b, 61c, the secondary pressure sensor 72, the hydrogen secondary pressure regulator 62a, and the hydrogen starting electromagnetic valve 62b are the fuel supply pressure adjusting means 51 that adjusts the supply pressure of the hydrogen gas.

  The fuel supply pressure adjusting means 51 changes the supply pressure of the hydrogen gas to the set pressure of the hydrogen primary pressure regulators 61a, 61b, 61c or the set pressure of the hydrogen secondary pressure regulator 62a by switching between opening and closing of the hydrogen starting electromagnetic valve 62b. It is possible to switch to. In particular, the fuel supply pressure adjusting means 51 is configured to make the supply pressure of hydrogen gas at the time of starting power generation of the fuel cell 1 higher than the supply pressure at the time of normal power generation of the fuel cell 1, so that the hydrogen primary pressure regulator 61a. 61b, 61c is set to 0.3 MPa, for example, and is set higher than 0.1 MPa, which is the set pressure of the hydrogen secondary pressure regulator 62a.

  The fuel supply pressure adjusting means 51, the remaining pipes 53 and 54 of the supply path, the hydrogen supply electromagnetic valve 63, and the tertiary pressure sensor 73 are adjusted to a predetermined supply pressure from the hydrogen tank 50 to the supply port 21a. A fuel supply means for supplying the hydrogen gas is configured.

  Further, the pipes 56 and 57 are discharge paths, and the pipes 56 and 58 are sub discharge paths. Fuel for discharging exhaust hydrogen gas from the discharge port 21b through the discharge path by the pipes 56 and 57 as the discharge path, the drain tank 87 in which the level gauge 87a is built, and the hydrogen starting exhaust electromagnetic valve 67. A discharge means is configured, and a pipe 56, 58 as a sub discharge path, a hydrogen pump 81, and a hydrogen stop exhaust electromagnetic valve 68 are used to discharge the exhaust hydrogen gas from the discharge port 21b via the sub discharge path. A fuel discharge means is configured.

  Furthermore, the pipes 56, 59, and 54 are circulation paths that connect the discharge port 21b and the supply port 21a. The piping 56, 59, 54 as the circulation path, the hydrogen pump 81, and the hydrogen circulation electromagnetic valve 69 constitute fuel circulation means for supplying exhaust hydrogen gas to the supply port 21a.

  Further, the pipes 55, 59, 54 are outside air paths. The piping 55, 59, 54 as the outside air path, the filter 55b, and the outside air introduction electromagnetic valve 65 constitute outside air replacement means for supplying outside air to the supply port 21a and replacing the inside of the fuel chamber 12a with air. Yes.

  Further, an air manifold 42 for taking in air is provided above the fuel cell 1. An air intake fan 41 having a filter 41a is connected to the air manifold 42 so that air can be supplied into the air chamber 12b. The air manifold 42 is provided with a water injection nozzle 99. The water injection nozzle 99 is connected to a water tank 97 in which a level gauge 97 a is built by a pipe 98. The pipe 98 includes a filter 98 a and a water direct injection pump 83.

  Further, below the fuel cell 1, an air discharge path 90 having a temperature sensor 90a, a condenser 92, a condenser fan 93, and a duct 91 for guiding the discharged air from the air discharge path 90 to the condenser 92, Is provided so that air can be discharged from the air chamber 12b. The condenser 92 is capable of separating air and water. The condenser 92 includes a pipe 94 for discharging the separated air to the atmosphere, a filter 94a, and a temperature sensor 94b. A pipe 96 for transferring the water to the water tank 97, and a water recovery pump 82.

  The fuel supply means, the fuel supply pressure adjustment means 51, the fuel discharge means, the auxiliary fuel discharge means, the fuel circulation means, and the outside air replacement means are electrically connected to the control system 45 and can be controlled. The air suction fan 41, the level gauge 97a, the water direct injection pump 83, the temperature sensor 90a, the condenser fan 93, and other components are also electrically connected to the control system 45 and can be controlled.

  Here, the power generation starting means for starting the power generation by the predetermined power generation starting operation is a fuel supply means, a fuel discharge means, a fuel circulation means, a sub fuel discharge means, and a fuel supply pressure adjusting means. This power generation starting means is driven by the electric power stored in the power storage means described later.

  Further, the power generation stop means for stopping the power generation of the fuel cell 1 by a predetermined power generation stop operation is a fuel supply means, a fuel discharge means, a fuel circulation means, an outside air replacement means, a sub fuel discharge means, and a fuel supply pressure adjustment means. This power generation stopping means is driven by the electric power stored in the power storage means described later.

  In addition, the control system 45 includes control means that will be described in detail later with reference to FIGS. The control means has a power generation start time determination routine shown in FIG. 7 and a normal power generation time determination routine shown in FIG. The control means determines that an abnormality has occurred in the power generation start-up determination routine when the amount of power required for the power generation start operation of the fuel cell 1 is not in the power storage means described later. In the normal power generation determination routine, the fuel cell 1 It is determined that an abnormality has occurred when the amount of electricity necessary for the power generation stop operation is not in the electricity storage means described later. The control means issues an alarm signal when it is determined to be abnormal, and stops the fuel cell 1 with a predetermined abnormal stop operation.

  The fuel cell system 100 is mounted on an automobile and includes a capacitor 2 as a power storage means provided in parallel with the fuel cell 1 as shown in FIG.

  The fuel cell 1 and the capacitor 2 are connected to the external load device 7 in parallel. The external load device 7 is an auxiliary device (not shown) that controls auxiliary motors such as a drive motor and fuel supply means (not shown) and a drive motor.

  A relay 3, a diode 4 and an IPM (Intelligent Power Module) 5 constituting a part of the control system 45 are connected in series to a terminal 1 a on the fuel electrode 11 a side of the fuel cell 1. On the other hand, a voltmeter 6 is connected to the capacitor 2 in parallel.

The relay 3 connects the fuel cell 1 to the external load device 1 or disconnects it from the external load device 1 , the diode 4 blocks current from the capacitor 2, and the IPM 5 The electric power supply between the capacitor 2 and the capacitor 2 is adjusted according to the situation.

  The voltmeter 6 constitutes a part of the control means, and measures the voltage between both terminals 2 a and 2 b of the capacitor 2. Here, the charged amount (w) of the capacitor 2 is proportional to the voltage between both terminals 2 a and 2 b of the capacitor 2. For this reason, the control means determines the “voltage value between both terminals 2a, 2b of the capacitor 2” (v) measured by the voltmeter 6 and “necessary for the power generation start operation of the fuel cell 1” by the power generation start time determination routine. When the capacitor 2 does not have the charged amount (Ws1) necessary for the power generation start operation of the fuel cell 1 by a simple method of comparing the threshold value (voltage value Vs1) corresponding to the charged amount (Ws1) (w <Ws1). ) Can be determined as abnormal. Further, the control means performs the “voltage value between the two terminals 2a and 2b of the capacitor 2” (v) measured by the voltmeter 6 and the “power storage necessary for the power generation stop operation of the fuel cell 1” by the normal power generation determination routine. By a simple method of comparing the threshold value corresponding to the amount (Ws1) ”(voltage value Vc1), when the capacitor 2 does not have the stored amount (Wc1) necessary for the power generation start operation of the fuel cell (w <Wc1) It can be determined as abnormal.

  Here, the “threshold value corresponding to the power storage amount (Ws1) necessary for the power generation start operation of the fuel cell” (Vs1) is the power storage required to complete the program at the time of power generation start of the fuel cell 1 shown in FIG. A voltage value corresponding to (quantity).

  Further, the “threshold value corresponding to the storage amount (Wc1) necessary for the power generation stop operation of the fuel cell” (Vc1) is the storage amount necessary for completing the program at the time of power generation stop of the fuel cell 1 shown in FIG. Is a voltage value corresponding to.

  In addition, about these Vs1 and Vc1, the considerable margin is added in consideration of the measurement error of the voltmeter 6, and the dispersion | variation by various driving | running conditions.

  An outline of the operation of the fuel cell system 100 configured as described above will be described. In this fuel cell system 100, during normal power generation of the fuel cell 1, air is taken in by the air suction fan 41 and the air manifold 42, and air is supplied into the air chamber 12b as shown in FIG. Then, hydrogen gas is supplied from the hydrogen tank 50 to the fuel chamber 12a through the supply port 21a by the fuel supply means. Thereby, an electrochemical reaction can be caused between the air electrode 11c and the fuel electrode 11b, and an electromotive force can be obtained.

  During this time, as shown in FIG. 1, exhaust hydrogen gas is resupplied from the discharge port 21 b to the supply port 21 a by the pipes 56, 59, 54, the hydrogen pump 81, and the hydrogen circulation electromagnetic valve 69, 57, 58, a drain tank 87 with a built-in level gauge 87a, a hydrogen start exhaust solenoid valve 67, and a hydrogen stop exhaust solenoid valve 68, exhaust hydrogen gas and generated water are intermittently discharged from the discharge port 21b of the fuel chamber 12a. In addition to being continuously transferred to the condenser 92 through the duct 91, the electrochemical reaction is continuously generated, and it is possible to suppress a decrease in performance due to excessive retention of water in the fuel chamber 12a. Yes.

  Further, the water in the water tank 97 is pumped by the water direct injection pump 83 and injected from the water injection nozzle 99 into the air manifold 42. Thereby, drying of the air electrode 11c is prevented and the fuel cell 1 is cooled. Further, the air containing water discharged from the air chamber 12 b of the fuel cell 1 is transferred from the air discharge path 90 to the condenser 92 through the duct 91. The air separated by the condenser 92 is discharged from the pipe 94 to the atmosphere, and the separated water is collected in the water tank 97 by the water collection pump 82. Similarly, the exhaust hydrogen gas and the generated water transferred to the condenser 92 via the duct 91 are separated into hydrogen and water, the hydrogen is discharged into the atmosphere together with the air, and the water is collected in the water tank 97. The

  Further, when the power generation of the fuel cell 1 is started, first, both the hydrogen start exhaust solenoid valve 67 and the hydrogen stop exhaust solenoid valve 68 are switched to open according to the program shown in FIG. Then, air is taken in by the air suction fan 41 and the air manifold 42, and air is supplied into the air chamber 12b. At the same time, the hydrogen supply electromagnetic valve 63 is switched to open, and the hydrogen tank 50 passes through the supply port 21a. Then, hydrogen gas is supplied into the fuel chamber 12a. At this time, by switching the hydrogen starting electromagnetic valve 62b of the fuel supply pressure adjusting means 51 to open, a high supply pressure of hydrogen gas can rapidly flow into the fuel chamber 12a. Then, after the hydrogen starting solenoid valve 62b, the hydrogen starting exhaust solenoid valve 67, and the hydrogen stop exhaust solenoid valve 68 are switched to shut off, the normal power generation state is checked through a normal pre-power generation check. For this reason, the fuel cell system 100 can rapidly implement replacement of the air replaced in the fuel chamber 12a with newly supplied hydrogen gas when power generation is stopped. For this reason, generation | occurrence | production of the state where air and hydrogen gas are unevenly distributed in the fuel chamber 12a can be suppressed notably. Thus, the fuel cell system 100 can suppress the problem that the fuel cell 1 is deteriorated at the time of power generation start-up. Further, the time required for replacing the gas in the fuel chamber 12a is shortened, and the time required for starting the power generation of the fuel cell 1 can be shortened.

  Further, when the power generation of the fuel cell 1 is stopped, the supply of hydrogen gas from the hydrogen tank 50 into the fuel chamber 12a is first stopped by switching the hydrogen supply electromagnetic valve 63 to shut off according to the program shown in FIG. Then, the hydrogen circulation solenoid valve 69 is switched to shut-off, the hydrogen stop exhaust solenoid valve 68 is switched to open, and then suctioned by the hydrogen pump 81, so that the fuel chamber 12 a passes through the duct 91, the condenser 92 and the pipe 94. The hydrogen gas is discharged into the atmosphere. At this time, the inside of the fuel chamber 12a is in a reduced pressure state. Thereafter, the outside air introduction electromagnetic valve 65 is switched to open, external air is supplied to the supply port 21a, and the inside of the fuel chamber 12a is replaced with air. Then, the hydrogen pump 81 is stopped, and the outside air introduction solenoid valve 65 and the hydrogen stop exhaust solenoid valve 68 are switched to cutoff. As a result, the fuel cell system 100 can quickly eliminate the state in which the hydrogen gas in the fuel chamber 12a and the air in the air chamber 12b exist with the electrolyte membrane 11 in between when the power generation of the fuel cell 1 is stopped. In addition, hydrogen gas and air are not unevenly distributed in the fuel chamber 12a, and the inside of the fuel chamber 12a can be replaced with air. Thus, the fuel cell system 100 can suppress the problem that the fuel cell 1 deteriorates when power generation is stopped.

  In the fuel cell system 100 that operates in this manner, the control means determines that an abnormality has occurred in the determination routine at the time of power generation startup when the capacitor 2 does not have the amount of electricity necessary for the power generation startup operation of the fuel cell 1. In the power generation determination routine, it is determined that an abnormality has occurred when the capacitor 2 does not have the amount of electricity necessary for the power generation stop operation of the fuel cell 1. When the control means determines that there is an abnormality, it issues an alarm signal and stops the fuel cell 1 by a predetermined abnormal stop operation.

  That is, at the time of power generation start-up of the fuel cell 1, the above-described power generation start-up determination routine of the control means is executed according to the program shown in FIG. 7 prior to the program of FIG. For example, when the ignition key is turned on, or when the power generation is started again after being temporarily stopped due to the driving situation, the program of FIG. 7 is executed by the computer built in the control system 45. Is done.

  When this power generation start-up determination routine is executed, in steps S101 to S113, “voltage value between both terminals 2a and 2b of capacitor 2” (v) and “amount of power necessary for power generation start operation of fuel cell 1”. The threshold value (Vs1) corresponding to (Ws1) is compared. In this program, m is the number of comparisons between v and Vs1, and n is the number of times determined continuously as v <Vs1. The reason for this is to eliminate noise, errors and the like of the voltmeter 6.

  As a result, when the number m of comparisons between v and Vs1 reaches the specified number, the power generation activation time determination routine ends the detection process, and determines that the capacitor 2 is not short of the charged amount. And the operation | movement at the time of the electric power generation start-up of the fuel cell 1 is sequentially performed according to the program shown in FIG. For this reason, when the power generation of the fuel cell 1 is started, there is no situation where all the stored power of the capacitor 2 is consumed and the amount of stored electricity is lost.

  On the other hand, when the number of times n determined continuously as v <Vs1 has reached the number of times of abnormality determination, the power generation start-up determination routine determines in step S115 that the capacitor 2 has insufficient power storage. In step S117, the control means issues an alarm signal that the capacitor 2 is insufficient in the amount of electricity stored. As a result, the fuel cell system 100 recognizes the abnormality, moves to step S119, and performs processing necessary for a stop operation such as an inability to start display. For this reason, even if the capacitor 2 is insufficient in the amount of electricity stored, it is possible to avoid a situation in which all of the stored power in the capacitor 2 is consumed and the amount of electricity stored is lost when the power generation of the fuel cell 1 is started.

  Further, at the time of normal power generation of the fuel cell 1, determination by the above-described normal power generation determination routine is performed continuously or periodically at a relatively short interval according to the program shown in FIG. This is for always preparing for unexpected situations such as an abnormal stop due to a malfunction of the fuel cell 1.

  The program in FIG. 8 differs from the program in FIG. 7 in the threshold value Vc1 in the determination in step S103b and the processing contents in steps S115b and S119b.

  When this normal power generation determination routine is executed, in Steps S101 to S113, “Voltage value between both terminals 2a and 2b of capacitor 2” (v) and “Storage amount necessary for power generation stop operation of fuel cell 1” A threshold value (Vc1) corresponding to (Wc1) is compared.

  As a result, when the number m of comparisons between v and Vc1 reaches the specified number, the normal power generation determination routine ends the detection process and determines that the capacitor 2 is not short of the charged amount. As a result, the fuel cell system 100 continues the operation during normal power generation of the fuel cell 1 as it is. For this reason, even if the fuel cell 1 has to stop power generation due to some trouble under this situation, all the stored power of the capacitor 2 is consumed when the power generation of the fuel cell 1 is stopped, and the amount of power stored is lost. Things don't happen.

  On the other hand, when the number of times n determined continuously as v <Vc1 has reached the number of times of abnormality determination, the normal power generation determination routine determines in step S115b that the capacitor 2 is insufficient in power storage. Then, in step S117b, the control means issues an alarm signal that the capacitor 2 is short of the charged amount. As a result, the fuel cell system 100 recognizes the abnormality, moves to step S119b, and performs processing necessary for the stopping operation such as stopping the hydrogen supply. For this reason, even if the capacitor 2 is insufficient in the amount of electricity stored, it is possible to avoid a situation in which all the stored power in the capacitor 2 is consumed and the amount of electricity stored is lost when the power generation of the fuel cell 1 is stopped.

  For this reason, in the fuel cell system 100, when the power generation of the fuel cell 1 is started or stopped, the power supply from the capacitor 2 to the power generation starting means or the power generation stopping means is interrupted or becomes insufficient. Alternatively, it is possible to prevent a situation in which the power generation stopping means cannot be driven normally, and as a result, once the operation is shifted to the power generation start operation or the power generation stop operation, the processing can be completed.

  For this reason, the fuel cell system 100 can suppress the deterioration of the fuel cell 1 and the decrease in the durability of the fuel cell for the following reason.

  That is, if an alarm signal is issued at the time of power generation start-up of the fuel cell 1, the power supply from the capacitor 2 to the power generation start-up means is interrupted or becomes insufficient at the time of power generation start-up, and the operation at the time of power generation start-up is performed. It can be predicted that a situation will occur that stops in the middle. Therefore, if the power generation start operation is continued as it is, the air that can fill the fuel chamber 12a when the fuel cell 1 is in the power generation stop state cannot be replaced with hydrogen gas, and the hydrogen gas in the fuel chamber 12a cannot be replaced. It becomes clear that the fuel cell 1 deteriorates due to uneven distribution of air and air. For this reason, in order to prevent such deterioration of the fuel cell 1 in advance, the fuel cell system 100 can stop the operation at the start of power generation of the fuel cell 1 immediately after the start. And this fuel cell system 100 can also transfer to appropriate measures, such as a stop operation, immediately.

  Further, if an alarm signal is issued during normal power generation of the fuel cell 1, the power supply from the capacitor 2 to the power generation stop means is interrupted or insufficient when the fuel cell 1 is subsequently stopped. It can be predicted that there will be a situation in which the operation at the time of starting power generation stops halfway, for example, a situation in which the supply of hydrogen gas from the fuel supply means cannot be stopped. In this case, since hydrogen gas continues to be supplied thereafter, it is clear that the chemical reaction between the hydrogen gas and air continues in the fuel chamber 12a and the fuel cell 1 is deteriorated. Become. For this reason, in order to prevent such deterioration of the fuel cell 1 in advance, the fuel cell system 100 can immediately shift to appropriate measures such as a stop operation when an alarm is issued.

  Therefore, the fuel cell system 100 according to the first embodiment is unlikely to cause a decrease in durability of the fuel cell 1 based on the deterioration of the fuel cell 1.

  In particular, when replacing the air in the fuel chamber 12a with the pressurized supply of hydrogen gas when the power generation of the fuel cell 1 is started, the hydrogen start electromagnetic valve 67 shown in S15 of FIG. If this is not possible, the internal pressure in the fuel chamber 12a rises to a supply pressure higher than that during normal power generation, and damage may occur if the pressure resistance of the fuel chamber 12a is low. Such a situation can also be prevented for the reason described above.

  Further, when power generation of the fuel cell 1 is stopped, the hydrogen gas in the fuel chamber 12a is sucked by the hydrogen pump 81 and forcibly discharged to bring it into a reduced pressure state. If the hydrogen pump 81 shown in S24 of FIG. 6 cannot be operated due to an insufficient amount, the hydrogen gas in the fuel chamber 12a cannot be sufficiently replaced with air, and the fuel cell 1 deteriorates. However, the fuel cell system 100 can prevent such a situation for the above-described reason.

  For this reason, in the fuel cell system 100 of the first embodiment, the durability of the fuel cell 1 is not easily lowered due to the deterioration of the fuel cell 1.

  Further, in this fuel cell system 100, when the control unit issues an alarm signal, the control unit can immediately shift the fuel cell 1 to a predetermined abnormal stop operation so that the fuel cell 1 is surely in a power generation stop state. Therefore, the safety of the fuel cell system 100 can be further enhanced.

  In the above, the present invention has been described according to the first embodiment. However, the present invention is not limited to the first embodiment. For example, as a power storage unit, a lead secondary battery, a lithium ion secondary battery, or Needless to say, the present invention can be applied with appropriate modifications without departing from the spirit of the invention, such as using a nickel-hydrogen secondary battery.

  The present invention is applicable to a fuel cell system.

1 is a schematic configuration diagram according to a fuel cell system of Example 1. FIG. 1 is an exploded perspective view of a fuel cell according to a fuel cell system of Example 1. FIG. 1 is a schematic cross-sectional view of a fuel cell stack according to a fuel cell system of Example 1. FIG. 1 is a schematic configuration diagram of an electric circuit of a fuel cell system according to a fuel cell system of Example 1. FIG. 4 is a flowchart of a processing program at the time of starting power generation of the fuel cell according to the fuel cell system of Example 1. 6 is a flowchart of a processing program when power generation of the fuel cell according to the fuel cell system of Example 1 is stopped. 6 is a flowchart of a power generation start-up determination routine in the fuel cell control means according to the fuel cell system of the first embodiment. 4 is a flowchart of a normal power generation determination routine in the fuel cell control means according to the fuel cell system of Embodiment 1;

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fuel cell 2 ... Power storage means (capacitor)
7 ... External load device 11a ... Solid polymer membrane (electrolyte membrane)
11b ... Fuel electrode 11c ... Air electrode 12a ... Fuel chamber 12b ... Air chamber 51, 53, 54, 63, 73, 51a, 51b, 51c, 52a, 52b, 53, 54, 56, 57, 56, 57, 67, 87, 87a, 56, 58, 56, 58, 68, 81, 54, 56, 59, 54, 56, 59, 69, 81, 54, 55, 59 ... Power generation starting means (fuel supply means, fuel discharge means, Fuel circulation means, auxiliary fuel discharge means and fuel supply pressure adjustment means)
51, 53, 54, 63, 73, 51a, 51b, 51c, 52a, 52b, 53, 54, 56, 57, 56, 57, 67, 87, 87a, 56, 58, 56, 58, 68, 81, 54, 56, 59, 54, 56, 59, 69, 81, 54, 55, 59, 54, 55, 59, 54, 55, 59, 55b, 65 ... power generation stop means (fuel supply means, fuel discharge means, Fuel circulation means, outside air replacement means, auxiliary fuel discharge means, and fuel supply pressure adjustment means)
51a, 51b, 51c, 52a, 52b, 53, 54 ... supply path 51, 53, 54, 63, 73 ... fuel supply means (51 ... fuel supply pressure adjusting means, 53, 54 ... piping, 63 ... hydrogen supply solenoid valve 73 ... tertiary pressure sensor)
56, 57 ... Discharge path 56, 57, 67, 87, 87a ... Fuel discharge means (67 ... Hydrogen activated exhaust solenoid valve, 87 ... Drain tank, 87a ... Level gauge)
56, 58 ... sub-discharge passage 56, 58, 68, 81 ... sub-fuel discharge means (68 ... hydrogen stop exhaust solenoid valve, 81 ... hydrogen pump)
54, 56, 59 ... circulation path 54, 56, 59, 69, 81 ... fuel circulation means (69 ... hydrogen circulation solenoid valve, 81 ... hydrogen pump)
54, 55, 59 ... outside air passage 54, 55, 59, 55b, 65 ... outside air replacement means (55b ... filter, 65 ... outside air introducing solenoid valve)
DESCRIPTION OF SYMBOLS 100 ... Fuel cell system S101, S103, S105, S107, S109, S111, S113, S115, S117, S119, S103b, S105b, S117b, S119b ... Control means (S101, S103, S105, S107, S109, S111, S113, (S115, S117, S119 ... Power generation startup determination routine, S101, S103b, S105, S107, S109, S111, S113, S115b, S117b, S119b ... Normal power generation determination routine)

Claims (4)

Solid polymer membrane is sandwiched between the fuel electrode and an air electrode, a fuel cell having a fuel chamber for supplying the fuel gas to the fuel electrode and the fuel gas and air to generate electric power is supplied,
Power storage means capable of storing power generated by the fuel cell or power supplied from an external load device;
Power generation starting means that is driven by the electric power stored in the power storage means and starts power generation of the fuel cell by a predetermined power generation start operation;
A power generation stop means that is driven by the power stored in the power storage means and stops the power generation of the fuel cell by a predetermined power generation stop operation;
Emits fuel determined to alarm signal the power storage amount storage amount required when及beauty power generation stop operation is not in the accumulating means is an abnormality in the absence in the accumulating means occurs necessary for power generation startup operation of the battery Control means ,
The power generation starting means replaces the air in the fuel chamber with the pressurized supply of the fuel gas at the time of power generation start of the fuel cell,
The power generation stop means, when the power generation stop of the fuel cell, after the reduced pressure state is forcibly discharged fuel chamber of the fuel gas, characterized in der Rukoto those that substitute by introducing outside air Fuel cell system. 2. The fuel cell system according to claim 1, wherein a supply passage for supplying the fuel gas to the fuel chamber has a relief valve that is opened to the atmosphere when the internal pressure rises excessively.   3. The fuel cell system according to claim 1, wherein the control unit is configured to stop the fuel cell with a predetermined abnormal stop operation when the alarm signal is issued. 4. Solid polymer membrane is sandwiched between the fuel electrode and an air electrode, a fuel cell having a fuel chamber for supplying the fuel gas to the fuel electrode and the fuel gas and air to generate electric power is supplied,
Power storage means capable of storing power generated by the fuel cell or power supplied from an external load device ;
Power generation starting means that is driven by the electric power stored in the power storage means and starts power generation of the fuel cell by a predetermined power generation start operation;
In an operation method of a fuel cell system, comprising: a power generation stop unit that is driven by electric power stored in the power storage unit and stops the power generation of the fuel cell by a predetermined power generation stop operation .
The power generation starting means replaces the air in the fuel chamber with the pressurized supply of the fuel gas at the time of power generation start of the fuel cell,
The power generation stop means, when power generation of the fuel cell is stopped, forcibly exhausts the fuel gas in the fuel chamber to a reduced pressure state, and then introduces and replaces outside air.
Emits fuel determined to alarm signal the power storage amount storage amount required when及beauty power generation stop operation is not in the accumulating means is an abnormality in the absence in the accumulating means occurs necessary for power generation startup operation of the battery A method for operating a fuel cell system.

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