JP6936758B2 - Deterioration diagnosis method for fuel cell power generation equipment - Google Patents

Description

The present invention relates to a method for diagnosing deterioration of fuel cell power generation equipment, and more particularly to a technique for more accurately diagnosing deterioration of equipment of fuel cell equipment.

In recent years, improvements in fuel cell power generation facilities have progressed, and it has become possible to supply electric power and supply hot water for home use. A fuel cell power generation facility is a power generation device that can continuously extract power by supplying some replenishable negative electrode active material and oxygen in the air, which is the positive electrode active material, in a normal temperature or high temperature environment and causing a chemical reaction. be. For example, low temperature type solid polymer type (PEFC), phosphoric acid type (PAFC), alkaline type (AFC), high temperature type molten carbonate type (MCFC), solid oxide type (SOFC), and other substances that become electrolytes. Although the type differs depending on the type, the fuel cell power generation facility generates power by using the fuel gas and the oxidizing agent gas supplied by using these electrolytes.

However, the output voltage of the fuel cell power generation facility tends to decrease because the equipment provided in the fuel cell power generation facility including the electric field quality deteriorates over time or by continuing the operation. Therefore, it is necessary to periodically stop the operation of the fuel cell power generation facility and check the deterioration state of each component. This is because if the operation is continued without inspection, there is a risk of damaging the fuel cell power generation facility in some cases. However, such a decrease in output voltage and the fact that periodic inspection of equipment is required hinders efficient power generation by fuel cell power generation equipment, and various technologies are being studied to cope with this.

Patent Document 1 discloses a technique relating to a fuel cell power generation facility, a control program, and a control method. The first mode in which the fuel cell power generation facility controls the flow rate of the fuel gas and the oxidant gas according to the external load, and at least in a state where the flow rate of the fuel gas is controlled to be substantially constant, the current to be drawn is substantially constant. A second mode for measuring the output voltage at the time of setting is selectively configured, and the current to be drawn out in a state where the control unit is controlled by the gas flow rate control means so that the flow rate of the fuel gas is at least substantially constant. Provided is an output voltage measuring means for measuring the output voltage when the value is substantially constant. Then, the storage means for storing the past output voltage measured by the output voltage measuring means, the current output voltage measured by the output voltage measuring means, and the past output voltage stored in the storage means are compared. Then, a deterioration diagnosis means for diagnosing the deterioration state of the fuel cell power generation facility based on the comparison result is provided, and when the second mode is selected, the deterioration state of the fuel cell power generation facility is checked during operation of the fuel cell power generation facility. Diagnose.

Japanese Patent No. 5099991

However, the technology described in Patent Document 1 deteriorates by storing the measurement result of the voltage of the fuel cell power generation equipment itself in the storage device provided in the main body of the fuel cell power generation equipment, as compared with its own past data. It is a prerequisite to make a diagnosis. Then, in order to perform the deterioration diagnosis, it is necessary to operate for a certain period of time in the second mode in which the flow rate of the fuel gas is controlled to be substantially constant and collect data. In this case, it is considered that it means that the deterioration can be judged only during the operation of the fuel cell power generation facility.

Further, in the second mode in which the deterioration diagnosis is performed, it is considered that it means that efficient power generation cannot be performed during that time. This is because the power generation output must be fixed to be substantially constant and operated for a certain period of time. Another problem is that the operation in the second mode needs to be performed regularly and data must be collected. This is because the operation in the second mode is considered to have lower power generation efficiency than the operation in the first mode, and as a result, the convenience to the user is considered to be impaired.

Further, in the self-deterioration diagnosis using the second mode, it is necessary to use the threshold value calculated from the design standard in consideration of the individual difference of the fuel cell power generation facility for the deterioration diagnosis. Therefore, there is a problem that the reference value has to be lowered. Such problems are considered to impair convenience for users.

Therefore, an object of the present invention is to provide a fuel cell power generation facility capable of more accurately diagnosing deterioration of equipment in order to solve such a problem.

In order to achieve the above object, the fuel cell power generation facility according to one aspect of the present invention has the following features.

(1) A fuel cell stack that generates electric power by the reaction of a fuel gas and an oxidant gas, a fuel gas supply means for supplying the fuel gas, an oxidant gas supply means for supplying the oxidant gas, and the fuel. A gas flow control means for controlling the gas supply means and the oxidant gas supply means, an output voltage measuring means for measuring the voltage of the generated electric power, and a storage means for constantly storing operation data including the value of the voltage. A plurality of the operation data fetched by the information fetching means are taken out from the fuel cell power generation facility provided with the information fetching means for fetching the information from the storage means, and a plurality of the operating data are taken out to the external computing device. The operation data obtained from the fuel cell power generation facility is collected, and a region in which the rated output operation is performed for a predetermined time is extracted from the operation data, compared in relation to the elapsed time and the output voltage, and the center thereof. It is characterized in that a threshold value is determined at a position deviating from a predetermined degree of deviation from the value, the fuel cell power generation facility corresponding to data below the threshold value is specified, and a deterioration state is diagnosed.

According to the embodiment described in (1) above, the operation data of a plurality of fuel cell power generation facilities is used to calculate a threshold value from the median value to diagnose the deterioration state of the fuel cell power generation facility, so that more accurate deterioration diagnosis can be performed. It will be possible. Compared to the case where the deterioration diagnosis is performed for the fuel cell power generation facility alone, this is because the information on another fuel cell power generation facility that is on the market and is in operation is taken into consideration, and the median value is used to obtain the threshold value. Because it can be done.

Operation data is taken out from the fuel cell power generation facility, operation data from multiple fuel cell power generation facilities is collected, the area where the rated output operation is performed is cut out from the operation data, and these operation data are used as an external computer. It is totaled in. Using this data, after plotting on a graph showing the relationship between the elapsed time and the output voltage, the median value is obtained to determine the threshold value, and the fuel cell power generation facility corresponding to the data exceeding the threshold value is specified. For this reason, equipment that is out of the standard of other fuel cell power generation equipment that is on the market and is in operation can be detected early by deterioration diagnosis, and it is possible to prevent troubles such as stopping the operation function in advance. ..

(2) In the method for diagnosing deterioration of fuel cell power generation equipment according to (1), the information extraction means is a wireless communication means provided in the fuel cell power generation equipment, and the operation data is transmitted to an external terminal by the wireless communication means. Taken out and input to the computing device from the external terminal,
Is preferable.

According to the aspect described in (2) above, the operation data of each fuel cell power generation facility can be aggregated by communicating with the external terminal from the wireless communication means, so that the data can be collected more easily. For example, when reading the amount of gas used, fuel cell power generation equipment installed at home is in an environment where it is relatively easy to collect operation data. Therefore, by combining the wireless communication means with the fuel cell power generation facility, data can be collected more easily and the accuracy of the data can be improved.

(3) In the method for diagnosing deterioration of fuel cell power generation equipment according to (1), the information extraction means is a wired communication means that connects to a wired communication network and communicates with the computing device. It is preferable that the information is input to the computing device.

According to the embodiment described in (3) above, data is collected using a wired communication network such as the Internet, so that it is possible to save the trouble of collecting data. Since technologies such as smart meters that connect to the Internet to collect data have been developed, it is possible to share information more efficiently by collecting data using such a network connection.

It is a block diagram of the fuel cell power generation facility of this embodiment. It is a graph which shows the relationship between the output voltage (V) and the elapsed time (h) of this embodiment.

First, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a block diagram of the system including the fuel cell power generation facility 100 according to the present embodiment. The fuel cell power generation facility 100 includes a desulfurization device 101, a reformer 102, a fuel cell stack 103, an exhaust gas heat exchanger 104, an ion exchange resin 105, an inverter 106, a control device 107, and a communication device 108. Has. In addition to this, there is a case where hot water is taken out from the exhaust gas heat exchanger 104 and used as exhaust heat in cooperation with a hot water storage tank (not shown), but the description thereof will be omitted in the present embodiment.

The fuel cell power generation facility 100 is connected to the network 10 and can communicate with the outside using the communication device 108, and another fuel cell power generation facility 200, the fuel cell power generation facility 300, and the like are connected to the network 10. , Is connected to the server 20. It is assumed that the fuel cell power generation facility 200 and the fuel cell power generation facility 300 connected to the network 10 have the same configuration as the fuel cell power generation facility 100.

The fuel cell power generation facility 100 is connected to a first line L1 for supplying air taken in as an oxidant gas and a second line L2 for supplying city gas as a fuel gas. The city gas is supplied to the fuel cell stack 103 via the desulfurizer 101 and the reformer 102, and the fuel cell stack 103 generates DC power by using the oxidizing agent gas and the fuel gas. The generated DC power is converted into AC power by the inverter 106 and supplied to an external load. The heat generated in the fuel cell stack 103 is exhausted after the heat is taken out by the exhaust gas heat exchanger 104, while the water taken out here is returned to the reformer 102 via the ion exchange resin 105. ..

It is the control device 107 that controls these and collects data during operation. The control device 107 stores the output voltage value and time data as operation data. The data of the output voltage value is constantly collected, and the data is periodically transmitted from the communication device 108 to the server 20 via the network 10. It is desirable that the connection to the network 10 is a wired line represented by an optical communication line or the like. For example, the communication device 108 has a function of performing wireless communication, and the meter reader of the gas meter has a dedicated external terminal. It may also be in the form of collecting data. In this case, a procedure is conceivable in which the external terminal and the fuel cell power generation facility 100 perform wireless communication, collect data, and then upload the data to the server 20.

Similarly, operation data is also collected from the fuel cell power generation facility 200 and the fuel cell power generation facility 300, and the data is aggregated on the server 20. FIG. 2 graphically shows the relationship between the output voltage (V) and the elapsed time (h). From the data obtained from a plurality of devices such as the fuel cell power generation facilities 100, 200, and 300, the region in which the rated output is operated for a predetermined time is extracted and used as comparative data. For example, the average value data of the output voltage is calculated by selecting a region in which the rated output operation is continuously performed for 10 minutes. Then, the points as shown in FIG. 2 are plotted. Since the output voltage tends to decrease with the passage of time, the graph shows a downward slope as a whole as shown in FIG.

Here, the median value med is calculated, and the threshold value is set to, for example, around 95% of the deviation degree, and the threshold value TL1 is set. The threshold value TL1 is a straight line parallel to the median med, and the three data included in the region A shown in FIG. 2 below are judged as signs of a decrease in power generation output. Such determined data is used to identify the corresponding fuel cell power generation facility 100. Then, the specified fuel cell power generation facility 100 is determined to have some abnormality, and the user is notified that "the tendency of the output power is seen, so please perform maintenance", or the technology. Personnel are dispatched to perform maintenance on the fuel cell power generation facility 100.

Since the deterioration diagnosis method of the fuel cell power generation facility 100 of the present embodiment has the above configuration, it exhibits the actions and effects described below.

First, as an effect, it is possible to perform deterioration diagnosis with higher accuracy. This is because the deterioration diagnosis method of the fuel cell power generation facility 100 of the present embodiment has the following configuration. That is, the fuel cell stack 103 that generates electric power by the reaction of the fuel gas and the oxidant gas, the fuel gas supply means for supplying the fuel gas (including the desulfurizer 101 and the reformer 102, and the second line L2). An oxidant gas supply means (including the first line L1) for supplying the oxidant gas, a control device 107 corresponding to a gas flow rate control means for controlling the fuel gas supply means and the oxidant gas supply means, and generated electric power. A fuel cell power generation facility including an output voltage measuring means for measuring the voltage of the fuel, a storage means for constantly storing operation data including a voltage value, and a communication device 108 corresponding to an information taking out means for extracting information from the storage means. A plurality of operation data taken out by the communication device 108 is taken out from the 100, and the operation data obtained from the plurality of fuel cell power generation facilities 100, 200, and 300 is collected in the server 20 corresponding to the externally provided computing device. Then, from the operation data, a region in which the rated output is operated for a predetermined time is extracted, compared in relation to the elapsed time and the output voltage, and the threshold value TL1 is set at a position deviating from the predetermined deviation degree from the median value med. It is characterized in that it is determined, the fuel cell power generation facility corresponding to the data of the threshold value TL1 or less is specified, and the deterioration state is diagnosed.

Conventionally, the deterioration judgment has been diagnosed by using the design assumption threshold value TL2 as shown in FIG. This is set from a numerical value assuming variations in manufacturing at the time of designing the fuel cell power generation facility 100. However, it is designed even if the capacity is slightly different from the average operation data of other fuel cell power generation equipment 200 and fuel cell power generation equipment 300 (so-called market machine) of the same type on the market. At the assumed threshold value TL2, it may be determined that there is no problem. The same can be said for Patent Document 1, which is a method for comparing with own past data. This is because even if the equipment of the fuel cell power generation facility 100 tends to deteriorate slightly faster than other market machines, it is difficult to check if there is no significant performance deterioration.

However, it is disadvantageous for the user that it is judged that there is no problem even if the numerical value deviates from the operation results of many market machines. Therefore, as in the present embodiment, data from a large number of market machines (including fuel cell power generation facilities 100, 200, and 300) are collected, the median value is obtained, and the threshold value TL1 is set. The data included in the area A shown in 2 can also be judged to deteriorate quickly and maintenance can be recommended. Since the threshold value TL1 is determined by the set degree of deviation, it is also an advantage that the threshold value can be determined without being affected by the operating state and output state of the device.

Although the embodiment of the deterioration diagnosis method for the fuel cell power generation facility 100 according to the present invention has been described above, the present invention is not limited to this, and various changes can be made without departing from the spirit of the present invention.

10 Network 20 Server 100, 200, 300 Fuel cell power generation equipment 101 Desmelter 102 Reformer 103 Fuel cell stack 104 Exhaust heat exchanger 105 Ion exchange resin 106 Inverter 107 Controller 108 Communication device

Claims (3)

A fuel cell stack that generates electric power by the reaction of fuel gas and oxidant gas,
A fuel gas supply means for supplying the fuel gas, an oxidant gas supply means for supplying the oxidant gas, and the like.
A gas flow rate control means for controlling the fuel gas supply means and the oxidant gas supply means,
An output voltage measuring means for measuring the voltage of the generated electric power, and
A storage means for constantly storing operation data including the voltage value, and
From a fuel cell power generation facility provided with an information extraction means for extracting information from the storage means.
A plurality of the operation data taken out by the information taking-out means are taken out, and the operation data is taken out.
The operation data obtained from the plurality of fuel cell power generation facilities is collected in an externally provided computing device, and the operation data is collected.
From the operation data group including the operation data from other fuel cell power generation facilities, the area where the rated output operation is performed for a predetermined time is extracted, compared in relation to the elapsed time and the output voltage, and from the median value. Determine the threshold at a position outside the specified degree of deviation,
Identifying the fuel cell power generation facility corresponding to the data below the threshold value and diagnosing the deterioration state.
A method for diagnosing deterioration of fuel cell power generation equipment. In the method for diagnosing deterioration of fuel cell power generation equipment according to claim 1.
The information extraction means is a wireless communication means provided in the fuel cell power generation facility.
The operation data is taken out to an external terminal by the wireless communication means, and the operation data is taken out to an external terminal.
Input to the calculation device from the external terminal,
A method for diagnosing deterioration of fuel cell power generation equipment. In the method for diagnosing deterioration of fuel cell power generation equipment according to claim 1.
The information retrieval means is a wired communication means that connects to a wired communication network and communicates with the computing device.
Input to the computing device from the wired communication means,
A method for diagnosing deterioration of fuel cell power generation equipment.

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