JP2013206773A - Fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in the operation control of a fuel cell system that when the fuel cell system cannot start power generation at a scheduled power generation start time because the temperature of the hot water storage tank is high and power generation is disabled, such as when the tank is filled, activation of the fuel cell system is delayed and the duration of power generation is shortened, and that when the length of power generation time is less than an expected time, resource saving, environment burden and economy of power generation become worse than when the fuel cell is not activated.SOLUTION: To solve the conventional problem, the present invention sets a shortest power generation time which is a minimum value of power generation time with which resource saving or environmental or economical merits can be secured, as compared with the case where the fuel cell is not activated. When a duration until a stop time becomes shorter than the shortest power generation time, the fuel cell system is not activated or the stop time is extended so that the shortest power generation time can be fulfilled.

Description

  The present invention relates to a fuel cell system that generates electric power and heat.

  In a fuel cell system equipped with a fuel cell or gas engine, in order to effectively use the heat generated by the fuel cell, the heat collected by supplying cooling water is stored in the tank as hot water, and the hot water is used for hot water supply, etc. What to do is known. However, there is an upper limit to the amount of heat stored in the tank, and when the amount of heat stored in the tank reaches the upper limit, the heat generated in the fuel cell cannot be recovered and the power generation efficiency decreases. For this reason, the future power demand and heat demand are predicted based on the past operation results, and a plurality of fuel cell operation plans are created based on the prediction result and the state and heat storage amount of the fuel cell at that time. One of the selected operation plans is selected according to predetermined criteria such as energy consumption, cost, and CO2 emission, and the presence or absence of power generation of the fuel cell is controlled based on the selected operation plan. However, no matter what operation plan is created, the actual power and heat consumption may deviate from the power and heat demand forecast that is the basis of the applied operation plan. . In order to solve this problem, for example, in Patent Document 1, when the actual load is deviated from the forecast due to reasons such as power generation restrictions and the planned operation is stopped, the means for prohibiting the restart by deviating from the planned time zone Is stated.

JP 2011-003483 A

  However, if the temperature of the hot water storage tank is high and power generation is prohibited, for example, when the fuel cell system is in the full storage state, power generation cannot be started even when the fuel cell system reaches the power generation start time. Become. When the power generation time length is equal to or less than a certain time, there is a problem that when power is generated, resource saving, environmental performance, or economic efficiency is worse than when the fuel cell is not started. Here, “full storage” means that the water in the hot water storage tank is sufficiently heated and cannot store heat any more, that is, the temperature in the hot water storage tank is equal to or higher than a first allowable temperature (for example, 70 ° C.). .

  In order to solve the conventional problems, the present invention provides a fuel cell system including a fuel cell that generates power using a fuel gas containing hydrogen and an oxidant gas, and at least the fuel cell system is activated. A storage unit that stores an operation plan in which a start time to perform and a stop time to stop and a shortest power generation time that is the shortest time during which the fuel cell system generates power, and power generation of the fuel cell system are prohibited When the power generation prohibition state is detected, control is performed so that the fuel cell system is not started even when the start time is reached, and the fuel cell system is started after the power generation prohibition state is no longer detected. And a control unit. In particular, the control unit is unable to start the fuel cell system at the start time due to detection of the power generation prohibition state, and even if the power generation prohibition state is not detected thereafter, the power generation prohibition state When the time from the time when the engine is no longer detected until the stop time becomes shorter than the shortest power generation time, the fuel cell system is controlled not to be activated.

  In the present invention, when the power generation prohibition state is detected, the fuel cell system cannot be started at the start time, and then the power generation prohibition state is not detected even if the power generation prohibition state is not detected. When the time from the stop time to the stop time becomes shorter than the shortest power generation time, the fuel cell system is not started, or the stop time is extended so as to keep the shortest power generation time, thereby saving resources or It is possible to drive without deteriorating environmental performance or economy.

The block diagram which shows the structure of the system in Embodiment 1 of this invention. The figure which shows an example when the electric power generation limitation in Embodiment 1 of this invention does not occur The figure which shows an example in which the electric power generation limitation in Embodiment 1 of this invention occurred before the starting time of the operation plan, was canceled before the shortest electric power generation time, and the fuel cell started The figure which shows an example in which the electric power generation limitation in Embodiment 1 of this invention occurred before the starting time of the driving plan, was canceled after the shortest electric power generation time, and the fuel cell did not start. The flowchart which shows the process of the control part in Embodiment 1 of this invention. The figure which shows an example which the electric power generation limitation in Embodiment 1 of this invention occurred before the starting time of the driving | operation plan, was cancelled | released after the shortest electric power generation time, and the fuel cell started and extended and stopped time was generated. The flowchart which shows the process in FIG. 6 of the control part in Embodiment 1 of this invention.

  1st invention is a fuel cell system provided with the fuel cell which generates electric power using fuel gas and oxidant gas containing hydrogen, Comprising: At least the starting time which the said fuel cell system starts, and the stop time which stops A storage unit that stores an operation plan in which the fuel cell system generates power and a shortest power generation time that is the shortest time for generating power, and a power generation prohibition state in which power generation of the fuel cell system is prohibited is detected. A control unit that does not start the fuel cell system even when the start time is reached, and controls the fuel cell system to start after the power generation prohibition state is no longer detected. . The control unit detects the power generation prohibition state even if the fuel cell system cannot be started at the start time due to the detection of the power generation prohibition state and thereafter the power generation prohibition state is not detected. The fuel cell system is configured to control the fuel cell system not to be activated when the time from when it stops to the stop time becomes shorter than the shortest power generation time.

  According to the first invention, when the time until the stop time is shorter than the shortest power generation time, the power generation efficiency is not generated, so that the operation with poor power generation efficiency can be avoided.

  A second invention includes a fuel cell for supplying electric power and heat, a heat accumulator for accumulating heat supplied by the thermoelectric supply device, a heat amount detector for detecting a heat load consumed by a user from the amount of heat of the heat accumulator, A remote control for setting a power generation start time or both a power generation start time and a power generation stop time by a user, and a control unit for controlling the fuel cell are provided. The control unit is configured to determine an optimal power generation start time and stop time of the fuel cell based on an electric power load and a heat load that are energy loads consumed by the user, and the power generation stop time from a current time. If the time until is longer than the shortest power generation time, the shortest power generation time determination means for granting power generation, the storage unit for storing the power load and heat load, the power generation start time and the stop time, a clock function and a calendar And when the fuel cell system cannot be started at the start time by detecting the power generation prohibition state, and when the power generation prohibition state is not detected thereafter, it is started and the shortest power generation time is It is a fuel cell system that controls to generate more power than the length.

  According to the second invention, when the time to the stop time is shorter than the shortest power generation time, the operation with poor power generation efficiency can be avoided by extending the stop time.

  According to a third aspect of the invention, particularly in the first or second aspect of the invention, further comprising: a heat accumulator that stores heat generated by power generation of the fuel cell; and a heat amount detector that detects the amount of heat stored in the heat accumulator. In the fuel cell system provided, the power generation prohibition state is a full state in which the amount of heat detected by the heat amount detector is equal to or greater than a predetermined first amount of heat.

  Here, the heat quantity detector may be a temperature sensor provided in the regenerator, or a temperature sensor that measures the temperature of the cooling water. In addition, a method of inspecting the amount of livestock heat by examining the amount of power generation may be used.

  In a fourth aspect of the invention, in particular, in the first to third aspects of the invention, the power generation prohibition state is obtained when the user continues power generation until the stop time of the fuel cell operation plan without using the heat accumulator. When the amount of heat detected by the detector is predicted to be equal to or greater than a predetermined first amount of heat, it is determined that the fuel cell is in the power generation prohibited state.

  According to the fourth invention, power generation can be continued without becoming full until the stop time of the operation plan regardless of whether the user uses hot water.

  According to a fifth aspect of the invention, particularly in the first to fourth aspects of the invention, the fuel cell performs a rated operation with a constant power generation amount, and the control unit is configured to perform the shortest operation according to an energy loss required for operation of the device. The power generation time was set.

  According to the fifth invention, when the energy loss required for the operation of the device is small, the shortest power generation time can be set to be short, so that even if the scheduled power generation time is short, resource saving or environmental or economic merit is secured. Thus, the fuel cell can be operated.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a configuration diagram of a fuel cell system 100 according to the present invention. The configuration of the present invention will be described below with reference to FIG.

  In FIG. 1, a fuel cell system 100 includes a fuel cell 101 that supplies electric power and heat, a heat accumulator 102 that accumulates heat supplied by a thermoelectric supply device, and a heat load consumed by a user from the amount of heat in the heat accumulator 102. And a remote controller 104 for setting a power generation start time or both a power generation start time and a power generation stop time, and a control unit 105 for controlling the fuel cell. In particular, the control unit 105 determines the optimal power generation start time and stop time of the fuel cell based on the power load and heat load that are energy loads consumed by the user, and the power generation stop from the current time. If the time until the time is longer than the shortest power generation time, the shortest power generation time determination means 107 that gives power generation permission, the power load and the heat load, the storage unit 108 that stores the power generation start time and the stop time, and a clock function It has a calendar function. The control unit 105 detects that the power generation prohibition state has failed to start the fuel cell system at the start time, and when the power generation prohibition state is not detected after that, the shortest power generation time determination unit determines that the power generation permission is permitted. It is controlled to start only during

  The heat accumulator is equipped with a burner, which may freeze due to a decrease in the outside air temperature and prevent freezing (hereinafter referred to as freezing prevention), or the sanitary condition of the solvent in the heat accumulator may be deteriorated. When performing (hereinafter referred to as reheating), the burner is ignited in order to prevent misjudgment that the gas meter is leaking gas because the gas consumption of the fuel cell is small (hereinafter referred to as avoiding shutting off the gas meter).

  The control unit is equipped with a clock function and a calendar function, and since it cannot detect the power generation prohibition state, it cannot start the fuel cell system at the start time. In a fuel cell system that controls the fuel cell system not to start or to extend the stop time so that the shortest power generation time can be observed when the time from when it is no longer detected until the stop time becomes shorter than the shortest power generation time. is there.

  As a means for the operation plan creation unit to calculate the power generation start time and the stop time of the fuel cell based on the user's power load and heat load, a method of referring to a reference pattern and power as in Patent Documents 2 to 5 There is a method of predicting the load of the day from the load or heat load and making a plan based on the prediction.

  The shortest power generation time is the minimum value of the power generation time that can secure the merit of resource saving, environmental performance, and economic efficiency as compared with the case where the fuel cell is not started. The shortest power generation time is determined by the energy loss of equipment required for operation. Here, resource saving refers to, for example, energy reduction. Environmentality is, for example, the amount of CO2 reduction. The economy is, for example, a gas fee.

  The power generation prohibition state is information on each state of full storage state, freezing prevention, reheating, avoidance of gas meter shutoff, and extreme heat response.

  As a result, when the power generation time length is equal to or less than a predetermined time, it is possible to perform an operation with less resource saving, environmental performance, or economic efficiency than when the fuel cell is not started.

  FIG. 1 which is a configuration diagram of an example when a power generation prohibition state in the fuel cell system 100 is not detected, FIG. 2 which shows an example when power generation restriction does not occur, and FIG. 5 which is a flowchart showing processing of a control unit, Will be described with reference to FIG.

  The operation plan means 106 plans to generate power from 12:00 to 20:00 at a certain time, for example, once a day at 0:00, with the user's power load and heat load stored in the storage unit 108 as the operation plan. Indicates the output case. The processing of the control unit is executed at regular time intervals, for example, every 5 seconds.

  In FIG. 2, when the current time is 11:59, when the process of the control unit is called (S100), it is determined whether the current time is between the power generation start time and the power generation stop time (S101). When it is determined that the current time 11:59 is before the power generation start time 12:00 (N in S101), a stop instruction is issued (S105), and the process ends (S106). When the current time is 12:00 in FIG. 2, when the process of the control unit is called (S100), the current time 12:00 is determined to be between the power generation start time 12:00 and the power generation stop time 20:00. (Y in S101), it is further determined whether or not there is a power generation limitation (S102). When the power generation limit is not set (Y in S102), the start time of the shortest power generation time is calculated as 18:00 from the power generation stop time 20:00 and the shortest power generation time 2 hours (S103). It is determined that the current time 12:00 is before the start time 18:00 of the shortest power generation time (S104), a power generation instruction is issued (S105), and the process ends (S107). In FIG. 2, when the current time is 20:01, when the process of the control unit is called (S100), it is determined that the current time 20:01 is later than the power generation end time 20:01 (S101), and a stop instruction is issued ( S106) and the process ends (S107).

Next, FIG. 1 is a configuration diagram of an example in which the fuel cell system cannot be activated at the activation time due to detection of the power generation prohibition state in the fuel cell system 100 and thereafter the power generation prohibition state is not detected. Referring to FIG. 3 showing an example in which the power generation restriction occurs before the start time of the operation plan, is released before the shortest power generation time, and the fuel cell is started, and FIG. 5 is a flowchart showing the processing of the control unit. explain.

  The operation plan means 106 plans to generate power from 12:00 to 20:00 at a certain time, for example, once a day at 0:00, with the user's power load and heat load stored in the storage unit 108 as the operation plan. Indicates the output case. The processing of the control unit is executed at regular time intervals, for example, every 5 seconds.

  In FIG. 3, the power generation restriction occurs at 11:58 and is released at 16:00. The minimum power generation time is 2 hours. When the current time is 11:59, when the process of the control unit is called (S100), it is determined that the current time 11:59 is before the power generation start time 12:00 (S101), a stop instruction is issued (S105), The process ends (S106). In FIG. 3, when the current time is 12:00, when the process of the control unit is called (S100), it is determined that the current time 12:00 falls between the power generation start time 12:00 and the power generation stop time 20:00 ( In step S101, it is determined that the power generation limit is further imposed (S102), a stop instruction is issued (S105), and the process ends (S106). When the current time is 16:00, the process of the control unit is called after the power generation restriction is released (S100), the current time 16:00 is between the power generation start time 12:00 and the power generation stop time 20:00. It is determined that the power generation is entered (S101), it is further determined that there is no power generation restriction (S102), and the start time of the shortest power generation time is calculated as 18:00 from the power generation stop time 20:00 and the shortest power generation time 2 hours (S103). ). It is determined that the current time 16:00 is before the start time 18:00 of the shortest power generation time (S104), a power generation instruction is issued (S105), and the process ends (S107).

  Next, even if the fuel cell system cannot be started at the start time due to the detection of the power generation prohibition state in the fuel cell system 100, and the power generation prohibition state is not detected thereafter, the shortest power generation time determination means generates power. FIG. 1 which is a block diagram of an example of a process that is activated only while permission is issued, and an example in which power generation restriction occurs before the start time of the operation plan, is released after the shortest power generation time, and the fuel cell does not start. A description will be given with reference to FIG. 4 and FIG. 5 which is a flowchart showing processing of the control unit.

  The operation plan means 106 plans to generate power from 12:00 to 20:00 at a certain time, for example, once a day at 0:00, with the user's power load and heat load stored in the storage unit 108 as the operation plan. Indicates the output case. The processing of the control unit is executed at regular time intervals, for example, every 5 seconds.

  In FIG. 4, the power generation restriction occurs at 11:58 and is released at 18:03. The minimum power generation time is 2 hours. When the current time is 11:59, when the process of the control unit is called (S100), it is determined that the current time 11:59 is before the power generation start time 12:00 (S101), a stop instruction is issued (S106), The process ends (S107). In FIG. 4, when the current time is 12:00, when the process of the control unit is called (S100), it is determined that the current time 12:00 falls between the power generation start time 12:00 and the power generation stop time 20:00 ( In step S101, it is determined that the power generation limit is set (S102), a stop instruction is issued (S106), and the process ends (S107). When the current time is 18:03, the process of the control unit is called after the power generation restriction is released (S100), the current time 18:03 is between the power generation start time 12:00 and the power generation stop time 20:00. It is determined that the power generation is entered (S101), it is further determined that there is no power generation restriction (S102), and the start time of the shortest power generation time is calculated as 18:00 from the power generation stop time 20:00 and the shortest power generation time 2 hours (S103). ). It is determined that the current time 18:03 is later than the start time 18:00 of the shortest power generation time (S104), a stop instruction is issued (S106), and the process ends (S107).

  By performing the processing as described above, when the time until the stop time is shorter than the shortest power generation time, power generation is not performed, so that an operation with poor power generation efficiency can be avoided.

Next, even if the fuel cell system cannot be started at the start time due to the detection of the power generation prohibition state in the fuel cell system 100, and the power generation prohibition state is not detected thereafter, the shortest power generation time determination means generates power. FIG. 1 is a block diagram of an example of a process that starts only while permitting, and the power generation restriction occurs before the start time of the operation plan, is released after the shortest power generation time, and the stop time of the fuel cell becomes the shortest power generation time. A description will be given with reference to FIG. 6 showing an example of starting by extending so as to maintain, and FIG. 7 being a flowchart showing processing of the control unit.

  The operation plan means 106 plans to generate power from 12:00 to 20:00 at a certain time, for example, once a day at 0:00, with the user's power load and heat load stored in the storage unit 108 as the operation plan. Indicates the output case. The processing of the control unit is executed at regular time intervals, for example, every 5 seconds.

  In FIG. 6, the power generation restriction occurs at 11:58 and is released at 18:03. The minimum power generation time is 2 hours. When the current time is 11:59, when the process of the control unit is called (S200), it is determined that the current time 11:59 is before the power generation start time 12:00 (S201), a stop instruction is issued (S207), The process ends (S208). In FIG. 6, when the current time is 12:00, when the process of the control unit is called (S200), it is determined that the current time 12:00 falls between the power generation start time 12:00 and the power generation stop time 20:00 ( In step S201, it is further determined that the power generation limit is set (S202), a stop instruction is issued (S207), and the process ends (S208). If the current time is 18:03, the process of the control unit is called after the power generation restriction is released (S200), the current time 18:03 is between the power generation start time 12:00 and the power generation stop time 20:00. It is determined that the power generation is entered (S201), and it is further determined that the power generation limit is not set (S202), and the start time of the shortest power generation time is calculated as 18:00 from the power generation stop time 20:00 and the shortest power generation time 2 hours (S203). ). It is determined that the current time 18:03 is after the start time 18:00 of the shortest power generation time (S204), and the power generation stop time is set to 20:30 in consideration of the current time 18:03 and the shortest power generation time of 2 hours. Change (S205) and end (S208). When the process of the control unit is called after 5 seconds (S200), it is determined that the current time 18:03 falls between the power generation start time 18:00 and the power generation stop time 20:30 (S201), and further power generation restrictions have been issued. (S202), the start time of the shortest power generation time is calculated as 18:30 from the power generation stop time 20:30 and the shortest power generation time of 2 hours (S203), and the current time 18:03 is the start time of the shortest power generation time. It is determined that it is before 18:30 (S204), a power generation instruction is issued (S205), and the process is terminated (S208).

  When the time until the stop time output by the operation planning means is shorter than the shortest power generation time by processing as described above, the operation with poor power generation efficiency is extended by extending the stop time to a time considering the shortest power generation time. Can be avoided.

  In the present embodiment, the water in the hot water storage tank is sufficiently heated as the full storage information, that is, the temperature in the hot water storage tank is higher than the first allowable temperature. Even if it can be predicted that full storage will occur, power generation may be limited.

  As described above, since the fuel cell system according to the present invention does not generate power when the time until the stop time is shorter than the shortest power generation time, operation with poor power generation efficiency can be avoided. Can be applied to the system.

DESCRIPTION OF SYMBOLS 100 Fuel cell system 101 Fuel cell 102 Heat accumulator 103 Heat quantity detector 104 Remote control 105 Control part 106 Operation plan means 107 Shortest power generation time determination means 108 Storage part

Claims (5)

A fuel cell system including a fuel cell that generates power using a fuel gas containing hydrogen and an oxidant gas,
A storage unit that stores at least an operation plan in which a start time at which the fuel cell system is started and a stop time at which the fuel cell system is stopped and a shortest power generation time that is the shortest time in which the fuel cell system generates power; and
When the power generation prohibition state in which the power generation of the fuel cell system is prohibited is detected, the fuel cell system is not started at the start time, and the fuel cell is not detected after the power generation prohibition state is not detected. A control unit that controls to start the system;
With
The control unit cannot detect the power generation prohibition state even if it cannot detect the power generation prohibition state after the fuel cell system cannot be started at the start time by detecting the power generation prohibition state. When the time from the stop time to the stop time is shorter than the shortest power generation time, control is performed so as not to start the fuel cell system.
Fuel cell system. A fuel cell system including a fuel cell that generates power using a fuel gas containing hydrogen and an oxidant gas,
A storage unit that stores at least an operation plan in which a start time at which the fuel cell system is started and a stop time at which the fuel cell system is stopped and a shortest power generation time that is the shortest time in which the fuel cell system generates power; and
When the power generation prohibition state in which the power generation of the fuel cell system is prohibited is detected, the fuel cell system is not started at the start time, and the fuel cell is not detected after the power generation prohibition state is not detected. A control unit that controls to start the system;
With
The control unit cannot detect the power generation prohibition state even if it cannot detect the power generation prohibition state after the fuel cell system cannot be started at the start time by detecting the power generation prohibition state. When the time from the time to the stop time is shorter than the shortest power generation time, the fuel cell system is started, and control is performed so that power is generated for the minimum power generation time or more from the time when the fuel cell system is started.
Fuel cell system. A heat accumulator for storing heat generated by power generation of the fuel cell;
A calorie detector for detecting the amount of heat stored in the heat accumulator;
In a fuel cell system further comprising:
The power generation prohibition state is a state in which the amount of heat detected by the heat amount detector is equal to or greater than a predetermined first heat amount.
The fuel cell system according to claim 1 or 2. In the power generation prohibited state, when the user continues power generation until the stop time of the operation plan of the fuel cell without using the heat accumulator, the amount of heat detected by the heat amount detector is equal to or greater than a predetermined first amount of heat. When it is predicted that the fuel cell is in the power generation prohibited state,
The fuel cell system according to any one of claims 1 to 3. The fuel cell shall be rated at a constant power generation amount,
The said control part sets the said shortest electric power generation time which is the shortest time which can collect | recover the energy loss required to drive | operate an apparatus at the time of starting and a stop based on electric power generation. Fuel cell system.

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