JP4716446B2 - Cogeneration system and operation control method thereof - Google Patents

Description

  The present invention relates to a cogeneration system including, for example, a fuel cell and a gas engine, and an operation control method thereof.

  FIG. 6 shows the fuel cell 1 and, for example, a hot water storage tank (heat source device) 3 and an operation control panel 4 that can store the exhaust heat of the fuel cell 1 but can be further heated with a heater such as a burner. Is a cogeneration system including a floor heating panel 5 that uses the hot water of the hot water supply system 2, and a floor heating controller 6 that controls the floor heating panel 5. In this system, a gas meter 7 called a “microcomputer meter” is interposed in a fuel cell and a gas supply line P (a city gas supply system as a gaseous fuel) to the hot water storage tank (heat source machine) 3.

  Taking fuel cell cogeneration as an example, the fuel cell needs to raise the temperature of the reformer for hydrogen production at start-up and must be heated by electricity and / or a gas burner. That is, for example, in a home equipped with a fuel cell, power consumption increases to some extent when the fuel cell is activated. Similarly, in the case of engine cogeneration, power consumption increases to some extent at startup.

  As shown in the characteristic diagram showing the change in power consumption over time in FIG. 8, the increase in power consumption due to the startup energy power Es means that the household power load is in the vicinity of the contract power WL, for example, 40A contract. , 38A (= about 3.8 kW) is consumed, the power consumption corresponding to the starting power Es occurs, so the contract power is exceeded (the hatched area ΔE in FIG. 8), and the state is In order to continue for more than a certain time, the breaker of the distribution board ("current controller", service breaker or ampere breaker) will fall and eventually the fuel cell (or engine) will also be forced to stop.

In the prior art, a technique for reducing the amount of activation energy of a cogeneration system (for example, a fuel cell cogeneration system) has been proposed (see Patent Document 1).
However, there has not yet been proposed an operation control method for suppressing the phenomenon that the breaker of the domestic distribution board falls due to the startup energy.

JP 2004-39430 A

The present invention ensures that when starting a means for outputting heat and electricity with fuel such as a fuel cell or an engine , the power consumption (power demand) increases and the contract power is exceeded. It aims at providing the cogeneration system which can be prevented, and its operation control method.

  According to the present invention, in a cogeneration system to which electric power is supplied via a breaker of a distribution board, the power consumption in the power device (5) and the means (1) for outputting heat and electricity by the fuel are measured. Measuring means (70) and control means (4), the control means (4) is a time before a predetermined time of starting the heat and electricity output means (1), When the difference obtained by subtracting the power consumption measured by the measuring means (70) from the contract power stored in advance is within a threshold, the means (1) for outputting heat and electricity is not activated, and the contract power is When the difference obtained by subtracting the power consumption measured by the measuring means (70) exceeds a threshold value, the means (1) for outputting heat and electricity is activated.

  And according to this invention, in the operation control method of the cogeneration system in which electric power is supplied through the breaker of the distribution board, the means (1) for outputting heat and electricity by the fuel, and the electric power device (5) Measuring means (70) for measuring power consumption, determining whether it is a time before a predetermined time before starting the means (1) for outputting heat and electricity by the fuel (S11), When the predetermined time has passed, the power consumption of the means (1) for outputting heat and electricity by the fuel and the power equipment (5) is measured by the measuring means (70) (S12) and stored in advance. It is determined whether or not the difference obtained by subtracting the current power consumption measured from the contract power amount is within a threshold value (S13). If the difference is within the threshold value, the means (1) for outputting heat and electricity is not activated, Within that threshold It is adapted to start the means (1) for outputting a thermal and electrical Invite Kere.

In the present invention, power demand and hot water supply demand are measured in advance, demand is predicted based on the measurement results, and the starting time of the means for outputting heat and electricity with fuel (for example, city gas) is determined in advance. Is preferred. The determined activation time is the above-described “time when the means for outputting heat and electricity by the fuel is activated”.
The means (1) for outputting heat and electricity by the fuel is preferably operated by automatic control.

  According to the present invention having the above-described configuration and control method, when the control means (operation control board 4) starts up the means (1) for outputting heat and electricity from the fuel, When the sum of the power consumption at the time is equal to or greater than the usable power (for example, contract power, fuel cell startable limit), the means (1) for outputting heat and electricity is not started, When the sum of the required power and the power consumption at the time is less than the usable power, the control is configured to start up, so that means for outputting heat and electricity by the fuel (for example, fuel It is possible to prevent the breaker of the distribution board from falling over the contract power due to the increase in power consumption at the time of starting the battery 1).

  The above effect can be achieved easily and accurately by using demand learning data in the operation control board (control panel 4), for example, to determine that “the fuel cell should not be started for how many hours later”. I can do it.

1 is a block diagram showing the overall configuration of an embodiment of the present invention. The characteristic view explaining the time-dependent change of electric power consumption regarding 1 embodiment of this invention. The control flowchart which shows the control method in one Embodiment of this invention. The block diagram which shows the whole structure of another embodiment of this invention. The control flowchart which shows the control method in another embodiment of this invention. The block diagram which shows the whole structure of the cogeneration system in a prior art. The characteristic view explaining the time-dependent change of the gas consumption of the cogeneration system in a prior art. The characteristic view explaining the time-dependent change of the power consumption of the cogeneration system in a prior art.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
In the following embodiment, a case will be described in which a fuel cell is employed as a device that outputs heat and electricity, and city gas that is gaseous fuel is used as fuel.

An embodiment will be described with reference to FIGS.
In FIG. 1, a cogeneration system generally indicated by B is a fuel cell (means for outputting heat and electricity by fuel) 1, a gas water heater (fuel consuming device) 3 that is a heat source device, and an operation control board. A hot water supply device 2 comprising a control panel 4, a floor heating panel 5 to which hot water heat is supplied from the gas water heater 3, and ON / OFF and temperature adjustment of the floor heating panel 5 connected to the gas water heater 3. It comprises a floor heating controller 6 to be performed and gas supply pipes P1 to P3 for supplying gas to the fuel cell 1 and the heat source unit 3.

  The control panel 4 receives a domestic power demand value and a power generation amount from the fuel cell 1 via, for example, a communication line. Then, a power generation command value and a start / stop command to the fuel cell 1 are sent out. Further, the control panel 4 is connected to a substrate (not shown) in the heat source device (hot water heater) 3 in the hot water supply device, and similarly configured to be able to acquire information such as the amount of heat used for floor heating in the hot water heater 3 through a communication line. Has been. Further, information and setting of the floor heating controller 6 connected to the water heater 3 can be made via communication.

  A gas meter 7 is interposed in the gas supply pipe P1, and a branch point J is provided downstream of the gas meter 7. At the branch point J, one of the supply pipes P2 connected to the fuel cell 1, The other is branched to P3 connected to the heat source machine. The gas meter 7 is configured as a type having both a function as a gas meter for the fuel cell 1 and a function as a gas meter for the heat source device (hot water heater) 3. Of course, a gas meter for the fuel cell 1 and a gas meter for the heat source unit (hot water heater) 3 may be provided separately.

  The floor heating panel 5 is connected by a hot water supply line Th so that the hot water heater 3 and the hot water can circulate.

  The control panel 4 is connected to the fuel cell 1 and the heat source unit 3 through control signal lines L1 and L2, respectively.

  Although not clearly shown, the fuel cell 1 and / or the heat source unit 3 incorporates a gas consumption measuring device. Alternatively, the amount of heat used can be counted by a thermistor or a flow meter and integrated with the gas consumption.

  A measuring instrument 70 dedicated to power consumption measurement is attached to the control panel 4 which is an operation control board.

  In one embodiment of FIGS. 1 to 3, the control panel 4 constantly measures and grasps the power consumption in the home via communication from the fuel cell 1 with respect to the increase in the power consumption during startup. Then, control is performed so that the fuel cell is not started until the power consumption is less than the power consumption that can start the fuel cell without dropping the breaker so that the fuel cell can be started without dropping the breaker of the switchboard. It is a form.

In the characteristic diagram showing the change over time of the power consumption in FIG. 2, even if the power consumption (characteristic line: solid line La) becomes equal to or less than the set threshold value W _α immediately before the fuel cell activation time, as indicated by a broken line Wα. Again, there is a case where the power consumption increases (broken line Lb).

Before the fuel cell startup time, even if a temporary power consumption equal to or less than the set threshold value W _alpha, again, whether phenomenon power consumption is increased (the phenomenon indicated by a broken line Lb) occurs, the power It can be grasped from the demand forecast result. Therefore, a time zone _Tα is determined based on the power demand prediction so that a situation in which the power demand becomes larger than the set threshold does not occur during the time required for activation (for example, 1 hour). And, such until the time zone T _α, it is controlled so as not to start the fuel cell 1.
In other words, the situation in which the power demand becomes larger than the set threshold during the time required for starting (1 hour) does not start the fuel cell 1 in the time zone predicted from the demand prediction. Is controlling.

  A control method of the cogeneration system as described above will be described with reference to FIG.

  First, in step S11, the control panel 4 determines whether or not the scheduled operation time of the fuel cell 1 is approaching. If the scheduled operation time is not approaching (NO in step S11), the loop of step S11 is repeated. On the other hand, if the scheduled driving time is approached (YES in step S11), the process proceeds to step S12.

  In step S12, the current power consumption (power demand) is measured, and in the next step S13, it is determined whether or not the value obtained by subtracting the power consumption from the contract power is within a threshold value. Here, the contract power can be obtained from a kitchen remote controller (not shown), and the numerical value can be changed when the power contract is changed.

  If the value obtained by subtracting the power consumption from the contract power is within the threshold (YES in step S13), the fuel cell is not started (step S15), the process returns to step S12, and step S12 and subsequent steps are repeated again. On the other hand, if the threshold value is exceeded (NO in step S13), the fuel cell is activated (step S14) and the control is terminated.

Next, a first modification of one embodiment will be described with reference to FIGS.
The first modification of FIGS. 4 and 5 is an embodiment in which control is performed so that no more power can be used if the fuel cell is started.

As shown in FIG. 4, the cogeneration system denoted as C as a whole includes a fuel cell 1, various electric product groups 50, a control panel 40 that is a control board, and power that measures the power consumption of each home appliance. It is constituted by a total 75 and a memory 8 as storage means.
A control method of this embodiment (first modification) will be described with reference to FIG.

  First, in step S21, the control panel 40 determines whether or not the scheduled operation time of the fuel cell 1 is approaching. If the scheduled operation time is not approaching (NO in step S21), the loop of step S21 is repeated. On the other hand, if it is close to the scheduled driving time (YES in step S21), the process proceeds to step S22.

  In step S22, the current power consumption (power demand) is measured, and in the next step S23, it is determined whether or not the value obtained by subtracting the power consumption from the contract power is within a threshold value.

  If the value obtained by subtracting the power consumption from the contract power is within the threshold (YES in step S23), the fuel cell 1 is not started (step S24), the process returns to step S22, and step S22 and subsequent steps are repeated again. On the other hand, if the threshold value is exceeded (NO in step S23), the fuel cell 1 is activated (step S25), and time measurement is started by a time counter (timer) (not shown) (step S26).

  In the next step S27, the control panel 40 determines whether or not the required time has elapsed. If the required time has elapsed (YES in step S27), the process proceeds to step S28. On the other hand, if the required time has not elapsed (NO in step S27), the process proceeds to step S29.

  In step S28, after the prohibition of new power demand (power consumption) by the communication line or the like is canceled from the control unit 40 to the various electric products 50, the control is terminated.

  In step S29, after prohibiting new power demand (power consumption), the process returns to step S27, and step S27 and subsequent steps are repeated.

It should be noted that the illustrated embodiment is merely an example, and is not intended to limit the technical scope of the present invention.
For example, although the fuel cell cogeneration system is illustrated in the illustrated embodiment, the means for generating heat and electricity is not limited to the fuel cell, and an internal combustion engine such as a gas engine is used. It is possible.
Moreover, although the case where a fuel cell and floor heating are used simultaneously is illustrated and described for the case where the gas consumption is constant, the gas using device is not limited to the floor heating device.
Furthermore, the fuel is not limited to city gas, but may be gas fuel other than city gas, liquid fuel such as petroleum or kerosene, and solid fuel (for example, powdered coal).

DESCRIPTION OF SYMBOLS 1 ... Fuel cell 2 ... Hot water supply device 3 ... Heat source machine 4 ... Operation control board / control unit 5 ... Floor heating panel 6 ... Floor heating controller 7 ... Gas meter / microcomputer Meter 70 ... Measuring instrument A ... Cogeneration system P1-P3 ... Gas supply pipe J ... Branch point

Claims (2)

In a cogeneration system in which electric power is supplied via a breaker of a distribution board, it has means for outputting heat and electricity with fuel, measuring means for measuring power consumption in at least power equipment, and control means. The control means has a threshold value obtained by subtracting the power consumption measured by the measurement means from the contract power quantity stored in advance at a time before a predetermined time before starting the heat and electricity output means. If the difference is less than the threshold value, the heat and electricity are output when the difference between the contracted power amount and the power consumption measured by the measuring means is exceeded. A cogeneration system having a function of activating means. In an operation control method of a cogeneration system in which electric power is supplied via a breaker of a distribution board, the apparatus includes means for outputting heat and electricity with fuel, and measuring means for measuring power consumption in at least electric power equipment, It is determined whether or not it is a predetermined time before the time for starting the means for outputting heat and electricity by the fuel, and if it is a predetermined time before, the means for outputting heat and electricity by the fuel and the power equipment, Is measured by the measuring means, and it is determined whether or not a difference obtained by subtracting the current power consumption measured from the contracted power stored in advance is within a threshold value. The cogeneration system operating system is characterized in that the means for outputting electricity is not activated and the means for outputting heat and electricity is activated unless the means is within the threshold. Method.

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