JP2010010029A - Fuel cell system and its control circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system with control means dispersed, having improved safety when a failure occurs in communicating the control means with each other, and an improved versatility in assigning an auxiliary machine to the control means. <P>SOLUTION: The fuel cell system comprises a main control means for controlling a series of operations of a fuel cell, represented by the start, power generation and stop of the fuel cell system, a sub control means for performing axiliary machine control determined by the control of the main control means, a fan and a pump for feeding air and water to be controlled by the control means including the main control means and the sub control means, and valves for changing over flow paths for gas, air and water. When a failure occurs in communicating the main control means and the sub control means with each other, the main control means and the sub control means independently perform stopping processing for the fuel cell. Thus, even when the failure occurs in communicating the control means with each other, the auxiliary machine connected to the sub control means can be controlled by the sub control means to stop the fuel cell. This improves the safety of the fuel cell when the communicating failure occurs. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a configuration of a fuel cell power generator.

  In recent years, new energy development for reducing carbon dioxide emissions has been actively conducted, and a fuel cell cogeneration system that is installed in each household and provides electric power and hot water is also in a practical stage.

  Household fuel cell systems that use city gas as a raw material consist of a hydrogen generator that extracts hydrogen from hydrocarbon-based source gas, a stack that generates electricity by reacting hydrogen and oxygen, and an inverter that converts the generated DC power into AC power Is composed of various auxiliary devices such as valves, pumps, heaters, fans and the like for controlling them, and a large number of temperature sensors and flow sensors are also mounted.

Since there are many components and these elements are large, the housing of the fuel cell device itself is naturally large. For this reason, for the purpose of reducing the number of wires and improving assemblability, for example, as shown in Patent Document 1, a method of distributing control devices like a main control device and a sub control device is known.
JP 2007-242330 A

  However, in the above-mentioned configuration, assuming that the control devices are coordinated by communication, if communication between the control devices becomes abnormal due to noise or disconnection of the communication line, the control device controls the auxiliary machine. The main controller shuts off the power supply. Therefore, if an auxiliary machine that is preferably operated for safety is connected to the sub-control means, an event that cannot be performed occurs when a communication abnormality occurs.

  In addition, if all the auxiliary equipment that needs to be operated when the fuel cell malfunctions are stopped, such as a ventilation fan that ventilates the air inside the machine or a cooling fan that cools the fuel cell system, assigns the auxiliary equipment and wiring. The degree of freedom is greatly impaired by the handling.

  In order to solve the conventional problems, a fuel cell stack that generates electricity by reacting hydrogen gas and oxidant gas, an inverter that converts electricity generated by the fuel cell stack into alternating current, the fuel cell stack, Sub-control means for controlling the inverter; in addition to control of the sub-control means, main control means for controlling system start-up, power generation and shutdown; valves for shutting off gas or water or switching the path; A pump and a fan for sending air and the like, and a sensor for measuring a temperature and a flow rate of gas, water, air, etc., and when the sub-control means detects the disconnection of communication with the main control means, Regardless of the auxiliary control instruction, the fan or pump is driven for the purpose of cooling or ventilation, the valve is controlled for the purpose of supplying or shutting off gas or water, and the main control means interrupts communication with the sub control means. Inspect Then, the valve located at the uppermost stream on the gas path is controlled to shut off the gas supply, the fan and pump are driven for cooling and ventilation, and the valve is controlled for the purpose of supplying and shutting off the gas and water. The sub-control means and the main control means control only the auxiliary devices connected to the respective control means and execute the fuel cell stop process alone.

  As a result, the fuel cell device of the present invention distributes the fuel cell control means to the main control means and the sub-control means, and when a communication abnormality occurs between these control means, the sub-control means instructs the auxiliary control command of the main control means. Therefore, even if an auxiliary device to be operated is assigned to the sub-control unit when the fuel cell is stopped, the fuel cell device can be safely stopped.

  Furthermore, since the degree of freedom increases in the arrangement of the auxiliary equipment and the assignment to the control means, the wiring length and the number of wirings can be reduced, and the product cost can be reduced.

  1st invention controls the fuel cell stack which reacts hydrogen gas and oxidant gas, and generates electric power, the inverter which converts the electric power generated with the fuel cell stack into alternating current, the fuel cell stack, and the inverter In addition to the control of the sub-control means, and the main control means for controlling the start, power generation, and stop of the system in addition to the control of the sub-control means, when communication between the main control means and the sub-control means is established, The sub-control means performs auxiliary equipment control as instructed by the main control means, and also transmits a sensor or switch input result to the main control means, and a communication abnormality occurs between the main control means and the sub-control means. The sub-control means controls the fans and pumps connected to the sub-control means for the purpose of cooling the fuel cell device and ventilating the air inside the machine, and controls the valves for the purpose of shutting off the gas and air and releasing the pressure. Means are raw materials In order to stop the gas supply, the most upstream valve in the gas path is closed and the fan and pump connected to the main control means are controlled for the purpose of cooling the fuel cell device and ventilating the air inside the machine. This is a fuel cell device.

  According to the above configuration and operation, in the fuel cell device in which the control means are distributed like the main control means and the sub-control means, for example, communication abnormality is caused by noise, disconnection of the communication line, poor contact of the connector, failure of the communication LSI, etc. When it occurs, the main control means controls the closing of the most upstream valve in the gas path, so that the outflow of new gas can be prevented, and the sub control means carries out the control for stopping the fuel cell by the sub control means alone. Therefore, when a communication abnormality occurs between the main control means and the sub-control means, the fan for ventilation is driven to prevent flammable gas from staying in the fuel cell apparatus, and the fuel cell apparatus and its components The effect that cooling becomes possible is brought about.

  There may be a plurality of sub-control means for the main control means.

  According to a second invention, in the first invention, the main control means has power shut-off means capable of shutting off power supply to the auxiliary equipment connected to the sub-control means, and the main control means is connected to the sub-control means. When a communication abnormality occurs, the power supply to the auxiliary machine is shut off by the power shut-off means after a lapse of a certain time or the temperature of a predetermined part in the fuel cell device has dropped below a certain temperature. This is a fuel cell system.

  According to the configuration and operation described above, even if a communication abnormality between the main control unit and the sub control unit is caused by the runaway of the sub control unit, the main control unit is connected to the control unit that is connected to the control unit in which the communication abnormality has occurred after a certain period of time. By shutting off the power supply to the machine, it is possible to prevent the malfunction of the auxiliary machine for a long time due to the runaway of the secondary control means.

  The third invention is an effective example in the case where several components related to system control are integrated as one control circuit among the components constituting the system in the first invention. is there.

  The fourth invention is an effective example in the case where several components related to system control are integrated as one control circuit among the components constituting the system in the second invention. is there.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment is an example and does not limit the present invention.

(Embodiment 1)
FIG. 1 shows an example of a configuration diagram of a whole system of a fuel cell device according to the present invention. A fuel cell device 1 that supplies electric power and a hot water storage device 13 that collects and stores exhaust heat generated in the fuel cell device 1. The configuration is shown.

  The fuel cell device 1 is a fuel that generates electric power by reacting hydrogen generated from a city gas as a raw material with hydrogen generating means 2, hydrogen generated by the hydrogen generating means 2 and oxygen in the air fed by an air pump 4. The battery stack 3, the inverter 8 for converting the generated power from direct current to alternating current, the exhaust heat recovery means 10 for recovering the exhaust heat generated during power generation, and the hot water storage communication means 9 for communicating with the hot water storage device 13 are provided. In order to control them, the main control means 5 and the sub control means 7 are connected via the communication line 6.

  The hot water storage device 13 communicates with the fuel cell device 1, a communication line 11, an exhaust heat recovery water path 12 for obtaining exhaust heat recovery water from the exhaust heat recovery means 10, and hot water storage means 16 for storing the exhaust heat recovery water. In order to control them, it has hot water storage control means 14 and is connected to the fuel cell device 1.

  FIG. 2 is a more detailed view of the fuel cell device 1, and the main control means 5 controls the gas control valve 20, the valve 21, the fan 22, and the air pump 4 installed at the uppermost stream of the raw material gas. The sub-control means 7 controls the valve 21, the fan 22, the air pump 4 and the inverter 8, and the auxiliary machine operation determined by the main control means 5 is transmitted to the sub-control means 7 via the communication line 6. In addition, the temperature, pressure, and flow rate input by the sensor 23 connected to the sub control means 7 are transmitted to the main control means 5 via the communication line 6. The sensor 23 connected to the main control means 5 is directly controlled by the main control means 5.

  When the communication with the sub-control unit 7 is normally performed, the main control unit 5 communicates with the sub-control unit 7 in order to instruct an auxiliary machine output or to obtain an input value from the sensor. The main control means 5 controls a series of operations typified by starting, generating and stopping the fuel cell device 1, and instructs the auxiliary control output to the sub-control means 7 so that the control means cooperate with each other in the fuel cell. The apparatus 1 is operated.

  Note that the main control means 5 and the sub control means 7 can monitor communication and detect a communication interruption caused by a communication abnormality. Communication interruptions between the main control means 5 and the sub-control means 7 are considered to be communication abnormality due to noise, disconnection of the communication line 6, contact failure of the connector connecting the communication line 6, and occurrence of abnormality in the LSI that controls communication. It is done.

  As shown in the processing diagram of the main control means 5 shown in FIG. 3A, the main control means 5 monitors the communication with the sub-control means 7 in step 100, and when communication interruption due to communication abnormality occurs, In step 102, the main control means 5 controls closing of the gas control valve 20 connected to itself, and controls the valve 21, the fan 22, and the air pump 4 to safely stop the fuel cell device.

  If no communication interruption has occurred, a series of operations represented by starting, generating, and stopping the fuel cell device 1 are controlled in cooperation with the sub-control means 7 in step 101.

  Hereinafter, the control in which the main control unit 5 or the sub control unit 7 stops the fuel cell device 1 only by using an auxiliary machine connected to the target control unit without communication is referred to as a single stop process.

  The single stop process is exemplified by controlling a valve to release gas when the pressure rises inside the hydrogen generating means 2, for example, controlling a fan or a pump to cool the fuel cell device 1 or ventilate the air in the apparatus. it can.

  The main control means 5 considers that the stop process of the fuel cell device 1 has been completed after a single time has elapsed in step 103 and after a predetermined time has elapsed or the temperature at a predetermined location has dropped to a constant temperature. The single stop process is completed.

  Note that the main control means 5 monitors the return of communication with the sub-control means 7 in step 100 even when the single stop is being executed, and when communication with the sub-control means 7 returns, the main control means 5 cooperates with the sub-control means 7 by communication. Then, the fuel cell device 1 may be stopped.

  As shown in the processing diagram of the sub-control means 7 shown in FIG. 3B, the sub-control means 7 constantly monitors the communication with the main control means 5 in step 104, and communication is interrupted due to a communication abnormality. In step 105, the valve 21, fan 22, air pump 4, and inverter 8 connected to the sub-control means 5 are controlled to stop the fuel cell device safely.

  When communication interruption has not occurred, auxiliary equipment control instructed by communication from the main control means 5 is performed in step 105, and the fuel cell apparatus 1 is controlled in cooperation with the main control means.

  For example, it can be exemplified that a valve is controlled to release gas when the pressure rises inside the hydrogen generating means 2, and a fan or pump is controlled to cool the fuel cell device 1 or ventilate the air in the apparatus. The sub-control means 7 performs the single stop process in Step 107 and, after a lapse of a certain time or after the temperature at a predetermined location has decreased to a constant temperature, it is considered that the stop process of the fuel cell device 1 has been completed. The single stop process is completed.

  The sub-control means 7 monitors the return of communication with the main control means 5 in step 104 even when the single stop is being executed, and when communication with the main control means 5 is restored, the auxiliary control means 5 transmitted from the main control means 5 is monitored. Control may be performed according to the machine control command.

  Thus, there is no need to concentrate and connect valves, fans, and pumps that are preferably operated in the stopping process from the viewpoint of safety of the fuel cell and prevention of deterioration, and the sub-control means 7 does not need to be connected to the main control means 5 in a concentrated manner. Since it can be connected, the degree of freedom of wiring layout for auxiliary equipment arrangement and auxiliary equipment control is increased.

(Embodiment 2)
In the second embodiment, in addition to the first embodiment, a configuration in which the main control means 5 can cut off the power supply to the auxiliary machine is added. Other configurations and operations are the same as those in the first embodiment. .

  In the following description, differences from the first embodiment will be mainly described, and other configurations and operations are the same as those of the first embodiment.

  FIG. 4 shows that the main control means 5 is connected to the sub-control means 7 from the power supply means 31 in order to prevent malfunction of the auxiliary equipment connected to the sub-control means 7 due to the communication interruption due to the runaway of the sub-control means 7. It is an example comprised from the power-supply-cutoff means 32 which can interrupt | block the power supply to a machine.

  As shown in the processing diagram of the main control means 5 shown in FIG. 5, when the main control means 5 detects a communication interruption with the sub-control means 7 at step 100, it executes the single stop process at step 102 and single stop at step 103. If the process is performed and a predetermined time has elapsed or if the temperature at a predetermined location has decreased to a certain temperature, it is considered that the stop process of the fuel cell device 1 has been completed, the single stop process is terminated, and step 110 is performed. Then, power supply to the auxiliary machine connected to the sub-control means 7 is shut off by the power shut-off means 32.

  With this configuration, even when communication is interrupted due to runaway of the sub-control means 7, it is possible to eliminate the malfunction of the auxiliary equipment connected to the sub-control means 7.

  When the main control means 5 runs away, the runaway detection means 30 detects the runaway due to the interruption of the watchdog pulse generated by the main control means 5 and is supplied from the power supply means 31 to the auxiliary machine by the power shut-off means 32. A configuration for cutting off the power supply is known.

  The fuel cell device and the control circuit of the present invention can improve the safety and the degree of freedom of wiring layout when the fuel cell device is distributedly controlled.

The block diagram which shows the whole structure of the fuel cell system which concerns on one embodiment of this invention The figure which shows the inside of the fuel cell apparatus which concerns on Embodiment 1. FIG. (A) Processing diagram of main control means according to embodiment 1, (b) Processing diagram of sub-control means according to embodiment 1. The figure which shows the inside of the fuel cell apparatus which concerns on Embodiment 2. FIG. Processing diagram of main control means according to embodiment 2

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel cell apparatus 2 Hydrogen production | generation means 3 Fuel cell stack 4 Air pump 5 Main control means 6 Communication line 7 Sub-control means 8 Inverter 9 Hot water storage communication means 10 Waste heat recovery means 11 Communication line 12 Waste heat recovery water path 13 Hot water storage apparatus DESCRIPTION OF SYMBOLS 14 Hot water storage control means 15 Fuel cell communication means 16 Hot water storage means 17 Gas | air or air or water path | route 20 Gas control valve 21 Valve 22 Fan 23 Sensor 30 Runaway detection means 31 Power supply means 32 Power supply interruption means

Claims (4)

A fuel cell stack for generating electricity by reacting hydrogen gas and oxidant gas;
An inverter that converts electricity generated by the fuel cell stack into alternating current;
Sub-control means for controlling the fuel cell stack and the inverter;
In addition to the control of the sub-control means, the system is composed of main control means for controlling system start-up, power generation, and stop,
When the main control unit detects an abnormality in communication with the sub control unit,
It is characterized by carrying out single stop processing,
When the sub-control unit detects an abnormality in communication with the main control unit,
A fuel cell system that performs a single stop process. A fuel cell stack for generating electricity by reacting hydrogen gas and oxidant gas;
An inverter that converts electricity generated by the fuel cell stack into alternating current;
Sub-control means for controlling the fuel cell stack and the inverter;
In addition to the control of the sub-control means, main control means for controlling system start-up, power generation, stop, and
The main control means is composed of power shut-off means for shutting off power supply to the auxiliary machine connected to the sub-control means,
When communication abnormality occurs between the main control unit and the sub control unit,
The fuel cell system, wherein the main control means stops power supply to the auxiliary machine controlled by the sub-control means after a certain time after the occurrence of the communication abnormality. A fuel cell stack for generating electricity by reacting hydrogen gas and oxidant gas;
An inverter that converts electricity generated by the fuel cell stack into alternating current;
Sub-control means for controlling the fuel cell stack and the inverter;
In addition to the control of the sub-control means, the system is composed of main control means for controlling system start-up, power generation, and stop,
When the main control unit detects an abnormality in communication with the sub control unit,
It is characterized by carrying out single stop processing,
When the sub-control unit detects an abnormality in communication with the main control unit,
A control circuit for a fuel cell system, which performs a single stop process. A fuel cell stack for generating electricity by reacting hydrogen gas and oxidant gas;
An inverter that converts electricity generated by the fuel cell stack into alternating current;
Sub-control means for controlling the fuel cell stack and the inverter;
In addition to the control of the sub-control means, main control means for controlling system start-up, power generation, stop, and
The main control means is composed of power shut-off means for shutting off power supply to the auxiliary machine connected to the sub-control means,
When communication abnormality occurs between the main control unit and the sub control unit,
The control circuit of a fuel cell system, wherein the main control means stops power supply to an auxiliary machine controlled by the sub-control means after a certain time after the occurrence of the communication abnormality.

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