JP2007059369A - Electric power detecting method of fuel cell and its application - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric power detecting method of a fuel cell in which a voltage, a current and a power factor of the fuel cell can be obtained before the fuel cell enters a regular operation. <P>SOLUTION: In a transit process where a variation rate of a transit voltage is calculated and a voltage declines from an initial voltage to a regular voltage after a fuel cell is started and supplies a load power, voltage values of a first reference time and a second reference time are grasped, and a variation rate of a voltage according to time is calculated, and based on its co-relation with the variation rate of the transit voltage and on a co-relation between the variation rate of the transit voltage and an output voltage of the fuel cell under a predetermined operation temperature and the output current of the fuel cell, a regular voltage value and a regular current value when a fuel cell enters a regular operation can be obtained. Furthermore, from the regular voltage value and the regular current value at a regular operation, the power factor is calculated to judge whether an output power of the fuel cell satisfies a rated output. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a kind of fuel cell power detection method and its application, in particular, the time and voltage characteristic curve of the fuel cell, the voltage and the operating temperature of the fuel cell, the output voltage of the fuel cell, and the fuel cell It relates to the fact that the electrical properties and operating temperature of the fuel cell can be obtained through the correspondence relationship between the output currents.

  A conventional fuel cell includes a battery core that outputs an electric power by causing an electrochemical reaction using a hydrogen-rich fuel (for example, methanol) and an oxygen fuel, and the operating state (for example, voltage / voltage) of the battery core. Current output) is achieved through the setting of the operating conditions of the fuel cell core, and the electric power generated by the fuel cell is output via the current collecting grid. Normally, it is necessary to monitor and control the power output status of this type of fuel cell by the control means. However, when the fuel cell is connected to a load at the time of constant current output, the voltage gradually decreases, and about several tens of times. FIG. 3 shows that the voltage can enter a steady constant voltage state after a second has elapsed. However, when a steady voltage / current value is detected through a circuit, it is necessary to pass a very long reaction time, which is considerably disadvantageous for the necessity of control, and real-time monitoring control cannot be performed. .

  In addition, the electric power output between the fuel cell and the secondary battery is adjusted by combining an electric energy output device such as a rechargeable lithium battery secondary battery in an electronic system that normally uses a fuel cell. Therefore, the power factor of the output of the fuel cell must be monitored and controlled in real time.

  In view of the fact that conventional fuel cells cannot react quickly to the output power from the fuel cell, the inventor of the present invention strives to improve a kind of battery power detection method. And the power factor can be monitored and controlled in real time.

  The main object of the present invention is to provide a kind of fuel cell power detection method, so that the voltage, current, and power factor output from the fuel cell can be obtained before the fuel cell enters a steady state. .

  Another object of the present invention is to provide a kind of fuel cell power detection method, and through the output characteristics of the fuel cell, the voltage, current output from the fuel cell during the transient process of the fuel cell, The power factor and its operating temperature can be obtained.

  It is a further object of the present invention to provide a kind of fuel cell power detection method, which is applied in a system combined with a secondary battery, and simultaneously monitors and controls the power output of the fuel cell in real time. The power output of the secondary battery can be adjusted to reach the output power required for the load.

  In order to achieve the above-mentioned object of the present invention, the present invention is a kind of fuel cell power detection method and its application. This fuel cell power detection method includes a fuel cell voltage / current discrimination means, and Provide electrical connection to the main control circuit, which is a circuit equipped with storage means, calculate the rate of change of transient voltage, start the fuel cell and supply load power, then the voltage is steady from the initial voltage In the transient process that falls to the voltage, the voltage values of the first reference time and the second reference time are captured, and the voltage / current change rate is used by the voltage / current discrimination means via the main control circuit. The main control circuit checks the correspondence relationship between the transient voltage change rate and the transient voltage change rate stored in the storage means, the output voltage of the fuel cell under a specific operating temperature, and the output of the fuel cell. Through the current correspondence, the fuel cell Obtain a steady voltage value and a steady current value when entering a normal state, and check whether the output power of the fuel cell satisfies the rated output, and obtain a steady voltage value and a steady current value obtained in the above step. The power factor is calculated via the main control circuit, and the step of determining whether or not the output power of the fuel cell satisfies the rated output is provided.

  Furthermore, the present invention is applicable to multi-energy output by combining the fuel cell with other electric energy output devices.

  In addition, the main control circuit of the present invention can include a temperature detection mechanism, which captures the initial voltage under no load of the fuel cell and also stores the fuel cell stored in the storage means. The operating temperature of the fuel cell can be obtained through the correspondence between the initial voltage under no load and the operating temperature of the fuel cell.

  In order to make an engineer familiar with the item understand the purpose, characteristics, and effects of the present invention, the following detailed description will be given with reference to the following specific examples and the accompanying diagrams. To do as follows.

  FIG. 1 is a related sketch diagram applied to a device including a fuel cell power detection method and a load circuit according to the present invention. Referring to FIG. 1, in the present invention, the fuel cell (1) is electrically connected to the main control circuit (2), and the main control circuit (2) is electrically connected to the load (3). The operation of the fuel cell (1) is operated via the main control circuit (2), and the electric power of the voltage converted by the fuel cell (1) is supplied to the use of the load (3). The fuel cell (1) is a kind of energy converter that generates electric power by causing an electrochemical reaction through a hydrogen-rich fuel, an oxygen fuel, and a catalytic material, and the fuel cell. The electric power generated by (1) is output to the main control circuit (2). The main control circuit (2) is a circuit comprising a voltage / current discriminating means and an accumulating means, and the voltage / current discriminating means calculates the rate of change of voltage with time, The accumulating means accumulates the correspondence relationship between the transition rate of the transient voltage, the fuel cell output voltage, and the current output from the fuel cell, and this correspondence relationship can exist directly in the form of a numerical table or a relational expression.

  The fuel cell (1) is a fuel cell manufactured using a manufacturing process of a printed circuit board.

  In addition, in the system using the fuel cell power detection method according to the present invention, the main control circuit (2) can be further provided with a temperature detection mechanism (21), and the temperature detection mechanism ( 21) can be a temperature detector such as a thermocouple, or any other device capable of detecting any temperature, whereby the temperature of the fuel cell (1) can be detected and this temperature can be detected. The operating temperature of the fuel cell (1) can be provided by feeding back the value to the main control circuit (2). Under this circumstance, the accumulating means accumulates the correspondence relationship between the change rate of the transient voltage and the operating temperature of the fuel cell, the output voltage of the fuel cell, and the output current of the fuel cell.

  FIG. 2 is an operation chart diagram of a system to which the fuel cell power detection method according to the present invention is applied. FIG. 3 is a sketch of the time-voltage relationship until the start-up operation of the fuel cell used in the present invention is stabilized. FIG. 4 is a sketch of the correspondence relationship between the change rate of the transient voltage and the operating temperature of the fuel cell, the output voltage of the fuel cell, and the output current of the fuel cell of the fuel cell power detection method according to the present invention. Referring to FIG. 2, the operation steps of the system to which the fuel cell power detection method according to the present invention is applied include Step 101, Step 102, Step 103, and Step 104. Based on the system that applies the fuel cell power detection method of the present invention, the operation step includes detecting the operating temperature of the fuel cell, starting operation of the fuel cell (1), and The temperature detection mechanism (21) feeds back the temperature state of the fuel cell (1) to the main control circuit (2), and step 102 calculates the rate of change of the transient voltage, as shown in FIG. The main control circuit (2) calculates the rate of change of the voltage with time via the voltage / current discrimination means, the initial voltage of the fuel cell (1) is V0, and this voltage V0 is unloaded. Corresponding to the characteristics at the specific operating temperature of the fuel cell, after the fuel cell (1) starts at time t0 and supplies the load (3) power, the voltage V0 can be gradually attenuated and the current Becomes a stable IS value (however, this current value at this time is not yet known), so that the first reference time t1 And the corresponding reference voltage values V1 and V2 at the second reference time t2, and the rate of change of the transient voltage via the main control circuit (2) can be calculated. The main control circuit (2) shows the correspondence between the change rate of the transient voltage and the operating temperature of the fuel cell, the output voltage of the fuel cell, and the output current of the fuel cell as shown in FIG. In addition, it is possible to obtain the voltage VS value and the current IS value when the fuel cell enters a steady state by corresponding the change rate of the operating temperature and the transient voltage obtained in the above step within the relationship. In step 104, it is inspected whether the output power of the fuel cell satisfies the rated output, and the power factor is calculated by the main control circuit (2) via the steady-state voltage VS and current IS obtained in the previous step. By calculating, the output power of the fuel cell (1) Whether the Tashi can be judged.

  In addition, referring to FIG. 3, the initial voltage V0 under no load of the fuel cell corresponds to the characteristic at the specific operating temperature of the fuel cell, whereby the initial voltage V0 under the no load via the main control circuit (2). The voltage V0 can be detected, and the storage means stores the correspondence between the initial voltage under the no load of the fuel cell and the operating temperature of the fuel cell, or the output voltage of the fuel cell, and the output current of the fuel cell. Thus, the operating temperature of the fuel cell can be obtained in a further step. Therefore, the operating temperature of the fuel cell in the step can be obtained by detecting the initial voltage V0 under no load of the fuel cell, or the fuel cell in the correspondence relationship in which the initial voltage V0 is directly stored by the storage means. Can be used as an operating temperature.

  FIG. 5 is a related sketch applied to the circuit device of the second embodiment provided with the fuel cell power detection method and load according to the present invention. Referring to FIG. 5, based on the above-described embodiment of the present invention, the fuel cell power detection method of the present invention can be used in a system including the second battery (4), and the main control is performed. The circuit (2) can be further advanced to include a logic unit (22), a memory device (23), and a DC transformer (24). The second battery (4) is a primary battery or a secondary battery that can convert chemical energy stored as another power generator into electrical energy, and generates and outputs power. For example, the second battery (4) can be a primary battery of an alkaline battery or a secondary battery of a lithium battery. Further, the logical operation unit (22) in the main control circuit (2) is a circuit having voltage / current discrimination means, and also operates the fuel cell (1) and the second battery (4). The memory device (23) is an integrated circuit providing storage means, storing the various information, and the DC transformer (24) (DC converter) is a buck logic means, Alternatively, it is provided with boost logic means, and by combining the voltage required for the load (3), the power output from the fuel cell (1) or the second battery (4) Convert to size and form.

  FIG. 6 is an operation chart of a second embodiment of the system to which the fuel cell power detection method according to the present invention is applied. Referring to FIG. 6, the operation steps of the application system of the fuel cell power detection method according to the present invention include step 201, step 202, step 203, step 204, and step 205. Based on the second embodiment of the system to which the fuel cell power detection method according to the present invention is applied, the operation step includes the step 201 for detecting the operation temperature of the fuel cell and the operation of the fuel cell (1). And the temperature detection mechanism (21) feeds back the temperature state of the fuel cell (1) to the main control circuit (2), and step 202 calculates the rate of change of the transient voltage, 3, the main control circuit (2) calculates the rate of change of the voltage with time through the voltage / current discrimination means, and the initial voltage of the fuel cell (1) is V0. Corresponding to the characteristics at the specific operating temperature of the fuel cell under no load and voltage V0, after the fuel cell (1) starts at time t0 and supplies load (3) power, the voltage V0 gradually decays And the current is stable IS value (however, this current value is not yet known) The voltage values V1 and V2 corresponding to the reference time t1 and the second reference time t2, respectively, can be captured, and the rate of change of the transient voltage via the main control circuit (2) can be calculated; The correspondence relationship between the transition rate of the transient voltage is inspected, and the main control circuit (2) has the transition rate of the transient voltage and the operating temperature of the fuel cell, the output voltage of the fuel cell, and the output current of the fuel cell as shown in FIG. In addition, the voltage VS value and the current IS value when the fuel cell enters a steady state are obtained by matching the operating temperature obtained in the above step and the change rate of the transient voltage within the relationship. In step 204, whether or not the output power of the fuel cell can be sufficiently supplied to the load is checked, and the main control circuit (2) uses the steady-state voltage VS and current IS obtained in the previous step. By calculating the power factor output by the fuel cell (1), the load To determine whether it meets the requirements. Step 205 adjusts the output power of the fuel cell, and whether the main control circuit (2) satisfies the demand of the load (3) via the power factor of the output of the fuel cell (1) obtained in the above step When the power factor output from the fuel cell (1) reaches the power factor of the maximum output of the fuel cell, if the power factor required by the load (3) still cannot be satisfied, the main control circuit The logic operator (22) in (2) can select the parallel power supply state of the second battery (4) and the fuel cell (1), and at the same time provides power output and via the DC transformer (24). Electric power output from the fuel cell (1) and the second battery (4) is converted into a stable voltage and supplied to the load (3).

  In addition, in the step, when the fuel cell (1) can supply the necessary power to the load (3) alone, the theoretical calculator (22) stops the power output of the second battery (4). The fuel cell (1) can be selected to supply power to the second battery (4) at the same time, thereby charging the second battery (4).

  Furthermore, the operation temperature of the fuel cell can be set to a specific value that is already known, and thus the step of detecting the operation temperature of the fuel cell can be omitted.

  Although specific embodiments of the present invention have been described above, the scope of the present invention is not limited and any person familiar with this technology is based on the spirit and scope of the present invention. Regarding various modifications and modifications, the modifications and modifications shall also belong to the claims of the present invention, and the protection scope of the present invention shall be based on those defined in the claims.

FIG. 3 is a related sketch applied to a device including a fuel cell power detection method and a load circuit according to the present invention. It is the operation chart figure of the system which applied the power detection method of the fuel cell which is the present invention. It is a sketch of the time-voltage relationship until the starting operation of the fuel cell used in the present invention is stabilized. It is a sketch of the correspondence of the change rate of the transient voltage of the fuel cell power detection method according to the present invention, the operating temperature of the fuel cell, the output voltage of the fuel cell, and the output current of the fuel cell. It is the related sketch figure applied to the circuit device of the 2nd Example provided with the electric power detection method and load of the fuel cell which is this invention. It is an operation chart figure of the 2nd example of the system to which the power detection method of the fuel cell which is the present invention is applied.

Explanation of symbols

(1) Fuel cell
(2) Main control circuit
(21) Temperature detection mechanism
(22) Logic operator
(23) Memory device
(24) DC transformer
(3) Load
(4) Second battery Step 101: Fuel cell operating temperature detection step 102: Transient voltage change rate calculation step 103: Transient voltage change rate correspondence check step 104: Fuel cell output power is rated output Inspect whether or not

Step 201: Detection of the operating temperature of the fuel cell Step 202: Calculation of the rate of change of the transient voltage Step 203: Inspection of the correspondence relationship of the rate of change of the transient voltage Step 204: Whether the output power of the fuel cell can be sufficiently supplied to the load Inspection step 205: Adjustment of the output power of the fuel cell

t0: Startup time
t1: First reference time
t2: Second reference time
V0: Initial voltage at t0
V1: Voltage at t1
V2: Voltage at t2
VS: Steady voltage
IS: Steady current

Claims (13)

In a kind of fuel cell power detection method,
providing the fuel cell with electrical connection to a main control circuit, which is a circuit comprising a voltage / current discrimination means and a storage means;
b. After calculating the rate of change of the transient voltage, starting the fuel cell and supplying load power, the voltage value of the first reference time and the second reference time in the transient process where the voltage drops from the initial voltage to the steady voltage And using the voltage / current discriminating means via the main control circuit to calculate the rate of change of the voltage with time,
c. The correspondence between the change rate of the transient voltage is inspected, and the main control circuit checks the correspondence relationship between the change rate of the transient voltage accumulated by the storage means, the output voltage of the fuel cell under a specific operating temperature, and the output current of the fuel cell. To obtain a steady voltage value and a steady current value when the fuel cell enters steady state, and
d. Inspect whether the output power of the fuel cell satisfies the rated output, and through the steady-state steady-state voltage value and steady-state current value obtained in the previous step, the power factor is obtained via the main control circuit. A method for detecting the power of the fuel cell, comprising the step of calculating whether or not the output power of the fuel cell is rated output. In the fuel cell power detection method according to claim 1, the method further proceeds,
a temperature detection mechanism included in the main control circuit that detects the operating temperature of the fuel cell, and the temperature detection mechanism detects the temperature state of the fuel cell when starting the operation of the fuel cell; Feedback to the control circuit;
b. In the inspection of the correspondence relation of the change rate of the transient voltage, the main control circuit determines the change rate of the transient voltage accumulated by the storage means, the operating temperature of the fuel cell, the output voltage of the fuel cell, and the output current of the fuel cell. A method for detecting the power of a fuel cell, comprising the step of obtaining a steady voltage value and a steady current value when the fuel cell enters a steady state through the correspondence relationship. 3. The fuel cell power detection method according to claim 2, wherein the temperature detection mechanism is achieved through a temperature detector. 4. The fuel cell power detection method according to claim 3, wherein the temperature detector can select either a thermocouple temperature detector or another temperature detector. . 3. The fuel cell power detection method according to claim 2, wherein the temperature detection mechanism captures the initial voltage under no load of the fuel cell, and stores the initial voltage under no load of the fuel cell stored by the storage means. The operating temperature of the fuel cell can be obtained through the correspondence relationship between the operating temperatures of the fuel cell. 3. The fuel cell power detection method according to claim 2, wherein the temperature detection mechanism captures the initial voltage under no load of the fuel cell, and changes the rate of change of the transient voltage stored in the storage means and the operating temperature of the fuel cell. A fuel cell power detection method comprising substituting an initial voltage for an operating temperature of a fuel cell within a correspondence relationship between an output voltage of the fuel cell and an output current of the fuel cell. 2. The fuel cell power detection method according to claim 1, further comprising: providing a second battery by going one step further; and further proceeding to the main control circuit by a logical operation unit, a memory device, a DC transformer, and A logic arithmetic unit comprising a voltage / current discrimination means, an integrated circuit for controlling the operation of the fuel cell and the second battery, and the memory device providing a storage means; and the DC transformer Comprises either a step-down logic means or a step-up logic means, and converts the power output from the fuel cell and the second battery in combination with the voltage required for the load to the corresponding voltage level. Forming a fuel cell power detection method. 8. The fuel cell power detection method according to claim 7, wherein the second battery is selected from a primary battery and a secondary battery. In the fuel cell power detection method according to claim 7, the method further proceeds,
a. Calculation of the power factor output from the fuel cell in the main control circuit via the steady-state steady-state voltage and steady-state current obtained in the previous step, and
b. The power output from the fuel cell is adjusted by adjusting the output power of the fuel cell and determining whether the main control circuit satisfies the load demand through the power factor of the fuel cell output obtained in the above step. When the power factor reaches the maximum output power factor of the fuel cell, if the power factor required by the load still cannot be satisfied, the logic unit of the main control circuit selects the parallel power supply state of the second battery and the fuel cell. At the same time, the power output is provided and the power output from the fuel cell and the second battery is converted into a stable voltage via the DC transformer and supplied to the load. The power detection method for a fuel cell according to claim 9, wherein when the fuel cell can supply the necessary power to the load alone, the theoretical computing unit can select the stop of the power output of the second battery, and The fuel cell can choose to power the second battery at the same time, thereby charging the second battery. 2. The fuel cell power detection method according to claim 1, wherein the correspondence relationship between the change rate of the transient voltage accumulated by the accumulation means, the fuel cell output voltage, and the current output from the fuel cell is a direct numerical table or a relationship. A method for detecting the power of a fuel cell, characterized in that the method can exist in a formula manner. 2. The method of controlling a power factor generated from a fuel cell according to claim 1, wherein the fuel cell is a fuel cell manufactured using a manufacturing process of a printed circuit board. Power factor control method. 4. The method of controlling a power factor generated from a fuel cell according to claim 3, wherein the second battery is selected from a primary battery and a secondary battery. Power factor control method.

Images