KR102651906B1 - Fuel cell control device and method with negative voltage detection function - Google Patents

Abstract

A fuel cell control device having a negative voltage detection function according to a preferred embodiment of the present invention includes a voltage sensing unit including a plurality of voltage sensing circuits that sense the voltage of each of a plurality of fuel cell stacks, the plurality of fuel cell stacks. A negative voltage sensing unit having a plurality of negative voltage sensing circuits for sensing each negative voltage, and when a negative voltage is generated in at least one of the plurality of fuel cell stacks 200, negative voltage sensing from the negative voltage sensing unit. It includes a determination unit that receives information and determines a negative voltage generation stack using the negative voltage sensing information, and a control unit that controls fuel supply to the plurality of fuel cell stacks in consideration of the determination result of the determination unit.

Description

Fuel cell control device with negative voltage detection function {FUEL CELL CONTROL DEVICE AND METHOD WITH NEGATIVE VOLTAGE DETECTION FUNCTION}

The present invention relates to a fuel cell control device with a negative voltage detection function.

In general, a fuel cell vehicle consists of a fuel cell stack consisting of a plurality of fuel cells stacked for use as a power source, a fuel supply system that supplies fuel such as hydrogen to the fuel cell stack, and oxygen, an oxidizing agent necessary for electrochemical reactions. It includes an air supply system that supplies water, and a water and heat management system that controls the temperature of the fuel cell stack.

The fuel supply system depressurizes the compressed hydrogen inside the hydrogen tank and supplies it to the anode (anode) of the stack, and the air supply system operates an air blower to supply sucked external air to the air electrode (cathode) of the stack.

When hydrogen is supplied to the fuel electrode of the stack and oxygen is supplied to the air electrode, hydrogen ions are separated at the fuel electrode through a catalytic reaction. The separated hydrogen ions are transferred to the anode, which is the air electrode, through the electrolyte membrane, and at the anode, the hydrogen ions separated from the fuel electrode, electrons, and oxygen undergo an electrochemical reaction together, through which electrical energy can be obtained.

Specifically, electrochemical oxidation of hydrogen occurs at the anode, and electrochemical reduction of oxygen occurs at the air electrode. Electricity and heat are generated due to the movement of electrons generated at this time, and water vapor or heat is generated through the chemical reaction of hydrogen and oxygen combining. Water is created.

An exhaust device is provided to discharge by-products such as water vapor, water and heat, and unreacted hydrogen and oxygen generated during the electrical energy generation process of the fuel cell stack, and gases such as water vapor, hydrogen and oxygen are released into the atmosphere through the exhaust passage. is discharged into the stomach.

Components such as an air blower, hydrogen recirculation blower, and water pump to drive the fuel cell are connected to the main bus terminal to facilitate starting the fuel cell. The main bus terminal includes various relays to facilitate power cutoff and connection. , a diode can be connected to prevent reverse current from flowing into the fuel cell.

The dry air supplied through the air blower is humidified through a humidifier and then supplied to the cathode (air electrode) of the fuel cell stack. The exhaust gas from the cathode is humidified by the water component generated internally and is delivered to the humidifier to create air It can be used to humidify dry air to be supplied to the cathode by a blower.

Meanwhile, the condition and performance of the fuel cell stack are determined by reacting sensitively to operating conditions, such as outside air temperature, coolant temperature, and current usage. If the vehicle continues to operate under poor driving conditions, the performance of the fuel cell stack will deteriorate in the short term, making it unable to meet the driver's required output. In addition, when a negative voltage is generated in a fuel cell stack under certain circumstances, wear or damage to the stack occurs, which affects the durability of the stack and shortens its lifespan.

Accordingly, a method is required to protect the fuel cell stack from negative voltage and increase the safety of fuel cell vehicles and the lifespan of the fuel cell stack.

Conventionally, to protect the fuel cell stack, a sensing IC (Integrated Circuit) senses the voltage of each fuel cell stack, and communication is performed between sensing ICs that are connected to each other in a daisy chain method. Afterwards, the MCU ((Micro Controller Unit)) receives the voltage measurement data of the fuel cell stack through an isolated communication IC, and uses the received voltage measurement data to control the hydrogen and air compression valves of the fuel cell vehicle, thereby reducing the sound of the fuel cell stack. It prevents wear and tear due to voltage generation.

This conventional technology has a problem in that it takes a long time to control the MCU after the actual negative voltage is generated due to the daisy chain communication structure.

Republic of Korea Patent Publication No. 2016-0059830

Accordingly, the present invention was developed in consideration of the above-mentioned circumstances. By additionally constructing a circuit that detects the negative voltage of the fuel cell stack while maintaining the daisy chain communication structure between sensing ICs, the MCU that responds to the negative voltage generation of the fuel cell stack is provided. The purpose is to provide a fuel cell control device equipped with a negative voltage detection function that can shorten the control time.

A fuel cell control device with a negative voltage detection function according to a preferred embodiment of the present invention for achieving the above object includes a voltage sensing unit having a plurality of voltage sensing circuits that sense the voltage of each of a plurality of fuel cell stacks; a negative voltage sensing unit including a plurality of negative voltage sensing circuits that sense the negative voltage of each of the plurality of fuel cell stacks; When a negative voltage is generated in at least one of the plurality of fuel cell stacks, a determination unit that receives negative voltage sensing information from the negative voltage sensing unit and determines a negative voltage generating stack using the negative voltage sensing information; and a control unit that controls fuel supply to the plurality of fuel cell stacks in consideration of the determination result of the determination unit.

The plurality of voltage sensing circuits may be connected to each other in a daisy chain manner.

Each of the plurality of negative voltage sensing circuits may include a negative voltage detection unit that senses the negative voltage of each of the plurality of fuel cell stacks, and a signal transmission unit that transmits the negative voltage sensing information of the negative voltage detection unit to the determination unit. there is.

The negative voltage detection unit includes a first inductor (L1), a second inductor (L2), a first capacitor (C1), a second capacitor (C2), and a ground connected to the positive voltage terminal of each of the plurality of fuel cell stacks. It includes a resistor (R_G), a first resistor (R_CL1) connected to the first inductor (L1), and a second resistor (R_CL2) connected to the second inductor (L2), and the first capacitor ( A Zener diode (ZD) connected to C1), and a MOSFET element whose gate terminal is connected to the ground resistance (R_G), the drain terminal is connected to the second resistor (R_CL2), and the source terminal is connected to the Zener diode (ZD). (MOSFET), wherein the first resistor (R_CL1), the second capacitor (C2), the Zener diode (ZD), and the MOSFET device (MOSFET) may be connected to a photo coupler (PC). .

The signal transfer unit includes a positive voltage source (VDD) connected to the photocoupler (PC), a pulldown resistor (R_PD) connected between the photocoupler (PC) and the ground, and a third capacitor connected in parallel to the pulldown resistor (R_PD). (C3), and may include an output terminal (FC_ND) connected to the determination unit 130.

The plurality of negative voltage sensing circuits may be connected in parallel to each other to sense the negative voltage of each of the plurality of fuel cell stacks.

The determination unit may include a plurality of signal dividing units that divide the negative voltage detection signals of each of the plurality of negative voltage sensing circuits, and a signal amplifying unit that amplifies the negative voltage detection signals divided by the plurality of signal dividing units. You can.

The determination unit may convert the level of the signal amplified by the signal amplifier into bits and determine a negative voltage generation stack using the converted bits.

According to the fuel cell control device and its control method having a negative voltage detection function according to a preferred embodiment of the present invention, a circuit for detecting the negative voltage of the fuel cell stack is additionally configured while maintaining the daisy chain communication structure between sensing ICs. By doing so, the control time of the MCU that responds to negative voltage generation in the fuel cell stack can be shortened.

In addition, by preventing damage to the fuel cell stack, the safety of the fuel cell vehicle, durability, and lifespan of the fuel cell stack are increased.

In addition, even in the event of a failure of the sensing IC or communication path, it is possible to determine which fuel cell stack generates negative voltage.

1 is a block diagram of a fuel cell control device with a negative voltage detection function according to a preferred embodiment of the present invention.
FIG. 2 is a detailed block diagram of the fuel cell control device equipped with the negative voltage detection function of FIG. 1.
Figure 3 is a diagram showing an example of a communication failure situation of a fuel cell control device equipped with a negative voltage detection function according to a preferred embodiment of the present invention.
Figure 4 is a block diagram showing the detailed configuration of a negative voltage sensing unit according to a preferred embodiment of the present invention.
FIG. 5 is a detailed circuit diagram of the first negative voltage sensing circuit of FIG. 4.
FIG. 6 is a detailed circuit diagram of a plurality of negative voltage sensing circuits of the negative voltage sensing unit of FIG. 4.
Figure 7 is a circuit diagram showing the determination unit of Figure 4 according to a preferred embodiment of the present invention.
Figure 8 is a circuit diagram showing an embodiment different from the determination unit of Figure 4.
FIG. 9 is a diagram showing an example of a negative voltage generation situation in each of a plurality of fuel cell stacks.
Figure 10 is a diagram showing an example of a negative voltage detection signal detected by a fuel cell control device equipped with a negative voltage detection function according to a preferred embodiment of the present invention.
FIG. 11 is a diagram showing voltage levels obtained by dividing the plurality of negative voltage detection signals of FIG. 10.
FIG. 12 is a diagram showing the results of signal amplification on a plurality of divided negative voltage detection signals of FIG. 11.
Figure 13 is a flowchart of a control method of a fuel cell control device with a negative voltage generation function according to a preferred embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. First, when adding reference signs to components in each drawing, it should be noted that the same components are given the same reference numerals as much as possible even if they are shown in different drawings. In addition, preferred embodiments of the present invention will be described below, but the technical idea of the present invention is not limited or restricted thereto, and of course, it can be modified and implemented in various ways by those skilled in the art.

1 is a block diagram of a fuel cell control device with a negative voltage detection function according to a preferred embodiment of the present invention. FIG. 2 is a detailed block diagram of the fuel cell control device equipped with the negative voltage detection function of FIG. 1.

Referring to Figures 1 and 2, the fuel cell control device 100 equipped with a negative voltage detection function according to a preferred embodiment of the present invention protects the fuel cell stack from wear or damage due to negative voltage generation and communication delay. In order to do this, by not only detecting the voltage of the fuel cell stack, but also providing a negative voltage sensing circuit that directly senses the negative voltage, it is possible to detect the point of occurrence of negative voltage faster than before, and prevent wear or burnout of the fuel cell stack. It is characterized by preventing.

The fuel cell control device 100 with a negative voltage detection function according to a preferred embodiment of the present invention includes a voltage sensing unit 110, a negative voltage sensing unit 120, a determination unit 130, and a control unit 140. , a power supply unit 150, and a communication unit 160.

The voltage sensing unit 110 is a device that senses the voltage of the fuel cell 200. Here, the fuel cell 200 may include a plurality of fuel cell stacks. The plurality of fuel cell stacks may include a first fuel cell stack 210, a second fuel cell stack 220, a third fuel cell stack 230, and a fourth fuel cell stack 240. The number of plurality of fuel cell stacks is not limited to this, and may be further increased or decreased as needed.

The voltage sensing unit 110 may be a voltage sensing IC (Integrated Circuit). The voltage sensing unit 110 may include a plurality of voltage sensing circuits. The plurality of voltage sensing circuits may include a first voltage sensing circuit 111, a second voltage sensing circuit 113, a third voltage sensing circuit 115, and a fourth voltage sensing circuit 117. The number of plurality of voltage sensing circuits is not limited to this, and may further increase or decrease depending on the number of stacks of the fuel cell 200.

The first voltage sensing circuit 111 may sense the voltage of the first fuel cell stack 210. The second voltage sensing circuit 113 may sense the voltage of the second fuel cell stack 220. The third voltage sensing circuit 115 and the voltage of the third fuel cell stack 230 can be sensed. The voltage of the fourth voltage sensing circuit 117 and the fourth fuel cell stack 240 can be sensed.

The first voltage sensing circuit 111, the second voltage sensing circuit 113, the third voltage sensing circuit 115, and the fourth voltage sensing circuit 117 may be insulated and connected to each other in a daisy chain manner. . That is, the voltage sensing information of the first voltage sensing circuit 111 sequentially passes through the second voltage sensing circuit 113, the third voltage sensing circuit 115, and the fourth voltage sensing circuit 117 to the communication unit 160. , and may be transmitted to the control unit 140.

In addition, the voltage sensing information of the second voltage sensing circuit 113 passes sequentially through the third voltage sensing circuit 115 and the fourth voltage sensing circuit 117 to be transmitted to the communication unit 160 and the control unit 140. You can.

Additionally, the voltage sensing information of the third voltage sensing circuit 111 may be transmitted to the communication unit 160 and the control unit 140 through the fourth voltage sensing circuit 117.

In one embodiment, among a plurality of voltage sensing circuits, a voltage sensing circuit located far from the control unit 140 on the communication path detects the negative voltage of the fuel cell stack, or a problem occurs in isolated communication with an adjacent voltage sensing circuit. In this case, a transmission delay or error in the detection signal of the corresponding voltage sensing circuit may occur. At this time, the control unit 140 cannot accurately determine when the negative voltage of the fuel cell stack is generated and the stack where the negative voltage is generated due to a transmission delay or error in the corresponding voltage sensing circuit, so there is a problem in controlling the fuel supply to the fuel cell 200. may occur.

The negative voltage sensing unit 120 is provided to solve the above problem and is a device that senses the negative voltage of each stack of the fuel cell 200. The negative voltage sensing unit 120 may be provided separately from the voltage sensing unit 110. The negative voltage sensing unit 120 may include a plurality of negative voltage sensing circuits that are electrically connected to each other. The plurality of negative voltage sensing circuits may include a first negative voltage sensing circuit 121, a second negative voltage sensing circuit 123, a third negative voltage sensing circuit 125, and a fourth negative voltage sensing circuit 127. You can. The number of negative voltage sensing circuits is not limited to this, and may further increase or decrease depending on the number of stacks of the fuel cell 200.

The first negative voltage sensing circuit 121 can sense the negative voltage of the first fuel cell stack 210. The second negative voltage sensing circuit 123 can sense the negative voltage of the second fuel cell stack 220. The third negative voltage sensing circuit 125 can sense the negative voltage of the third fuel cell stack 230. The fourth negative voltage sensing circuit 127 can sense the negative voltage of the first fuel cell stack 240.

The first negative voltage sensing circuit 121, the second negative voltage sensing circuit 123, the third negative voltage sensing circuit 125, and the fourth negative voltage sensing circuit 127 each determine the negative voltage of the fuel cell stack. When sensed, negative voltage sensing information can be transmitted to the determination unit 130.

The determination unit 130 may receive negative voltage sensing information from the negative voltage sensing unit 120. The determination unit 130 may use the negative voltage sensing information to determine when the negative voltage is generated and the negative voltage generation stack. The determination unit 130 may transmit determination information about the negative voltage generation point and the negative voltage generation stack to the control unit 140.

The control unit 140 may receive voltage sensing information from the voltage sensing unit 110. The control unit 140 may control fuel supply to the fuel cell 200 using voltage sensing information. Additionally, the control unit 140 may receive decision information from the determination unit 130. The control unit 140 can appropriately control fuel supply to the negative voltage generation stack using the determination information.

The power supply unit 150 may supply power for the functional operation of the voltage sensing unit 110 and the negative voltage sensing unit 120.

The communication unit 160 may be insulated and connected to a voltage sensing circuit at one end of the voltage sensing unit 100. The communication unit 160 may receive voltage information by communicating with a connected voltage sensing circuit. The communication unit 160 may transmit the received voltage information to the control unit 140.

Figure 3 is a diagram showing an example of a communication failure situation of a fuel cell control device equipped with a negative voltage detection function according to a preferred embodiment of the present invention.

Referring to FIG. 3, the fuel cell control device 100 equipped with a negative voltage detection function detects the fuel cell 200 from the negative voltage sensing unit 120 even if a communication failure occurs between the voltage sensing circuits of the voltage sensing unit 110. ) of negative voltage can be sensed, making it possible to process negative voltage sensing information without communication delay.

In one embodiment, a communication failure may occur between the second voltage sensing circuit 113 and the third voltage sensing circuit 115. At this time, the voltage information of the second fuel cell stack 220 sensed by the second voltage sensing circuit 113 is not transmitted to the control unit 140 due to a communication failure. The second negative voltage sensing circuit 123 can sense the negative voltage of the second fuel cell stack 220 regardless of a communication failure between the second voltage sensing circuit 113 and the third voltage sensing circuit 115. The second negative voltage sensing circuit 123 may transmit sensing information to the determination unit 130. The determination unit 130 may determine the generation and timing of the negative voltage of the second fuel cell stack 220 through the sensing information of the second negative voltage sensing circuit 123. The determination unit 130 may transmit determination information to the control unit 140.

The control unit 140 may check the negative voltage generation situation of the second fuel cell stack 220 through the judgment information of the determination unit 130 instead of the sensing information of the second voltage sensing circuit 113. Through this, the control unit 140 can control fuel supply to the negative voltage generation stack.

Figure 4 is a block diagram showing the detailed configuration of a negative voltage sensing unit according to a preferred embodiment of the present invention. Hereinafter, for ease of description of the invention, description of some of the components of the negative voltage sensing unit may be omitted.

Referring to FIG. 4, a block diagram of the detailed configuration of the first negative voltage sensing circuit 121, the second negative voltage sensing circuit 123, and the third negative voltage sensing circuit 125 can be seen.

The first negative voltage sensing circuit 121 includes a first negative voltage detection unit 121a that senses the negative voltage of the first fuel cell stack 210, and a determination unit that determines the sensing information of the first negative voltage detection unit 121a. It may include a first signal transmission unit 121b transmitting to 130.

The second negative voltage sensing circuit 123 determines the second negative voltage sensing unit 123a, which senses the negative voltage of the second fuel cell stack 220, and the sensing information of the second negative voltage sensing unit 123a. It may include a second signal transmission unit 123b that transmits the signal to the unit 130.

The third negative voltage sensing circuit 125 determines the third negative voltage sensing unit 125a, which senses the negative voltage of the third fuel cell stack 230, and the sensing information of the third negative voltage sensing unit 125a. It may include a third signal transmission unit 125b that transmits the signal to the unit 130.

The determination unit 130 includes a first signal dividing unit 131a that receives the sensing information of the first negative voltage sensing circuit 121, and a second signal dividing unit that receives the sensing information of the second negative voltage sensing circuit 123. unit 131b, a third signal dividing unit 131c that receives sensing information from the third negative voltage sensing circuit 125, and a first signal dividing unit 131a, a second signal dividing unit 131b, and a third signal dividing unit 131b. The signal dividing unit 131c may include a signal amplifying unit 133 that amplifies the signal strength for each sensing information and transmits it to the control unit 140.

FIG. 5 is a detailed circuit diagram of the first negative voltage sensing circuit of FIG. 4.

Referring to FIG. 5, the first negative voltage detection unit 121a includes a first inductor (L1), a second inductor (L2), and a first inductor (L1) connected to the positive voltage terminal of the fuel cell stack (200). It may include a capacitor (C1), a second capacitor (C2), and a ground resistance (R_G).

Additionally, the first negative voltage detection unit 121a may include a first resistor (R_CL1) connected to the first inductor (L1) and a second resistor (R_CL2) connected to the second inductor (L2). .

In addition, the first negative voltage detection unit 121a includes a zener diode (ZD) connected to the first capacitor (C1), a gate terminal connected to the ground resistor (R_G), and a drain terminal connected to the second resistor (R_CL2). It is connected and may include a MOSFET element whose source terminal is connected to a Zener diode (ZD).

Additionally, the first resistor (R_CL1), the second capacitor (C2), the Zener diode (ZD), and the MOSFET device may be connected to a photo coupler (PC). The photocoupler (PC) may transmit the voltage sensing information of the first negative voltage detection unit 121a to the first signal transfer unit 121b.

The first signal transfer unit 121b includes a positive voltage source (VDD) connected to the photocoupler (PC), a pulldown resistor (R_PD) connected between the photocoupler (PC) and the ground, and a second signal connected in parallel to the pulldown resistor (R_PD). 3 It may include a capacitor (C3) and an output terminal (FC_ND) connected to the determination unit. The first signal transmission unit 121b may transmit the voltage sensing information of the first negative voltage detection unit 121a to the determination unit 130.

The second negative voltage sensing circuit 123 and the third negative voltage sensing circuit 125 are configured almost identically to the first negative voltage sensing circuit 121, and can be confirmed through FIG. 6.

FIG. 6 is a detailed circuit diagram of a plurality of negative voltage sensing circuits of the negative voltage sensing unit of FIG. 4.

Referring to FIG. 6, it can be seen that the first negative voltage sensing circuit 121, the second negative voltage sensing circuit 123, and the third negative voltage sensing circuit 125 are connected to each other in parallel. Since the components of the second negative voltage sensing circuit 123 and the third negative voltage sensing circuit 125 are almost the same as those of the first negative voltage sensing circuit 121, they are replaced with the description of FIG. 5.

Each of the first negative voltage sensing circuit 121, the second negative voltage sensing circuit 123, and the third negative voltage sensing circuit 125 generates a high level negative voltage when a negative voltage in the fuel cell stack is generated. A detection signal may be transmitted to the determination unit 130. The detailed circuit configuration of the determination unit 130 will be described later with reference to FIGS. 7 and 8.

Figure 7 is a circuit diagram showing the determination unit of Figure 4 according to a preferred embodiment of the present invention.

Referring to FIG. 7, a circuit diagram of the determination unit 130 according to a preferred embodiment of the present invention can be seen.

The first signal dividing unit 131a is configured to divide the first negative voltage detection signal (Sig1) of the first negative voltage sensing circuit 121, and is connected to the output terminal of the first negative voltage sensing circuit 121. It may include a partial pressure resistance (R1).

The second signal dividing unit 131b is configured to divide the second negative voltage detection signal Sig2 of the second negative voltage sensing circuit 123, and is connected to the output terminal of the second negative voltage sensing circuit 123. It may include two voltage divider resistors (R2) and a third divider resistor (R3) connected between the second divider resistor (R2) and the ground.

The third signal dividing unit 131c is configured to divide the third negative voltage detection signal Sig2 of the third negative voltage sensing circuit 125, and the fourth signal dividing unit 131c is connected to the output terminal of the third negative voltage sensing circuit 125. It may include a voltage divider resistor (R4) and a fifth divider resistor (R5) connected between the fourth divider resistor (R4) and the ground.

The signal amplifying unit 133 may be configured to amplify the signal strengths of each of the first signal dividing unit 131a, the second signal dividing unit 131b, and the third signal dividing unit 131c. The signal amplifying unit 133 has a first input terminal (IN+) to which the first signal dividing unit 131a, the second signal dividing unit 131b, and the third signal dividing unit 131c are respectively connected, and a ground terminal is connected to the signal amplifying unit 133. It may include a second input terminal (IN-), a power input terminal (VCC) through which a positive voltage is input, a ground input terminal (VEE) through which a ground voltage is input, and an output terminal (OUT) through which an amplified signal is output.

Meanwhile, a sixth resistor (R6) may be connected between the ground and the second input terminal (IN-). Additionally, a seventh resistor R7 may be connected between the second input terminal (IN-) and the output terminal (OUT) of the signal amplifier 133. Additionally, a capacitor C33 may be connected to the output terminal (OUT) of the signal amplifier 133.

Figure 8 is a circuit diagram showing an embodiment different from the determination unit of Figure 4.

Referring to FIG. 8, the determination unit 130 according to another embodiment of the present invention detects the first negative voltage detection signal (Sig1), the second negative voltage detection signal (Sig2), and the third negative voltage without separate signal amplification. It may be configured to individually transmit the signal Sig3 to the control unit 140. Here, the determination unit 130 includes a capacitor (C_ESD), a pull-up resistor (R_PU) connected to the positive voltage source (VDD), a pull-down resistor (R_PD) connected to the ground, and a capacitor (C_ESD), a pull-up resistor (R_PU), and a pull-down resistor (R_PU). It may include a resistor (R_S) with one end connected to the resistor (R_PD) and the other end connected to the output terminal (FC_ND_MCU).

FIG. 9 is a diagram showing an example of a negative voltage generation situation in each of a plurality of fuel cell stacks.

FIG. 9 (a) is a diagram showing an example of a negative voltage generation situation in the first fuel cell stack 210. FIG. 9 (b) is a diagram showing an example of a negative voltage generation situation in the second fuel cell stack 220. FIG. 9 (c) is a diagram showing an example of a negative voltage generation situation in the third fuel cell stack 230.

9(a) to 9(b), the negative voltage of each of the plurality of fuel cell stacks is sensed by the negative voltage sensing unit 120, which may appear as shown in FIG. 10.

Figure 10 is a diagram showing an example of a negative voltage detection signal detected by a fuel cell control device equipped with a negative voltage detection function according to a preferred embodiment of the present invention.

Figure 10(a) shows an example of the negative voltage of the first fuel cell stack 210 sensed by the first negative voltage sensing circuit 121.

Figure 10(b) shows an example of the negative voltage of the second fuel cell stack 220 sensed by the second negative voltage sensing circuit 123.

Figure 10(c) shows an example of the negative voltage of the third fuel cell stack 230 sensed by the third negative voltage sensing circuit 125.

The first negative voltage sensing circuit 121, the second negative voltage sensing circuit 123, and the third negative voltage sensing circuit 125 each determine negative voltage sensing information of each of the plurality of fuel cell stacks through the determination unit 130. It can be sent to .

FIG. 11 is a diagram showing voltage levels obtained by dividing the plurality of negative voltage detection signals of FIG. 10.

FIG. 11 (a) is a diagram showing an example of the voltage level of the first negative voltage detection signal Sig1 divided by the first signal dividing unit 131a of the determination unit 130.

FIG. 11 (b) is a diagram showing an example of the voltage level of the second negative voltage detection signal Sig2 divided by the second signal dividing unit 131b of the determination unit 130.

FIG. 11 (c) is a diagram showing an example of the voltage level of the third negative voltage detection signal Sig3 divided by the third signal dividing unit 131c of the determination unit 130.

The first signal dividing unit 131a, the second signal dividing unit 131b, and the third signal dividing unit 131c each include a first negative voltage detection signal (Sig1), a first negative voltage detection signal (Sig2), And the first negative voltage detection signal (Sig3) may be transmitted to the signal amplifier 133.

FIG. 12 is a diagram showing the results of signal amplification on a plurality of divided negative voltage detection signals of FIG. 11.

Referring to FIG. 12, the determination unit 130 can detect one bit representing a negative voltage generation stack by sensing the level of the amplified signal that appears when a plurality of negative voltage detection signals are amplified through an analog port. In one embodiment, when there are three fuel cell stacks, the first fuel cell stack 210 is set as the most significant bit, and the third fuel cell stack 230 is set as the lowest bit. And the second fuel cell stack 220 may be set as a bit between the first fuel cell stack 210 and the third fuel cell stack 230. As shown in Table 1 below, approximately 8 bits representing a negative voltage generation stack can be set.

Negative voltage generation stack First fuel cell stack (210) Second fuel cell stack (220) Third fuel cell stack (230) 0 0 0 0 0 One 0 One 0 0 One One One 0 0 One 0 One One One 0 One One One

Meanwhile, the bits representing the negative voltage generation stack are not limited to the above number. In other words, if more fuel cell stacks need to be sensed, this can be done by increasing the number of bits or increasing the same negative voltage sensing circuit in parallel.

Figure 13 is a flowchart of a control method of a fuel cell control device with a negative voltage generation function according to a preferred embodiment of the present invention.

Referring to FIG. 13, the control method of the fuel cell control device having a negative voltage generation function detects whether or not negative voltage is generated in each of the plurality of fuel cell stacks, and when the negative voltage generating stack is confirmed, the negative voltage generating stack It is characterized by controlling the fuel supply to.

Referring to FIG. 13, the control method of the fuel cell control device having a negative voltage generation function includes a negative voltage detection step (S1310), a confirmation step (S1320), a control step (S1330), and a negative voltage release determination step (S1340). , a normal determination step (S1350), and a failure determination step (S1360).

In the negative voltage detection step (S1310), the negative voltage sensing unit 120 may sense the negative voltage of each of the plurality of fuel cell stacks. The determination unit 130 may receive negative voltage sensing information from the negative voltage sensing unit 120. The determination unit 130 may determine that the plurality of fuel cell stacks are normal when the negative voltage is not sensed according to the negative voltage sensing information.

In the confirmation step (S1320), when the generation of negative voltage is confirmed according to the negative voltage sensing information, the determination unit 130 obtains an information bit representing the negative voltage generation stack by dividing and amplifying the voltage level of the negative voltage sensing information. You can. If the negative voltage generating stack is not confirmed through the information bit, the determination unit 130 may determine that the plurality of fuel cell stacks are normal. When the negative voltage generation stack is confirmed through the information bit, the determination unit 130 may transmit the determination information to the control unit 140.

In the control step (S1330), the control unit 140 receives determination information from the determination unit 130, and when a negative voltage generation stack is confirmed according to the determination information, the control unit 140 may control fuel supply to the negative voltage generation stack. . In particular, the control unit 140 can control a valve that supplies hydrogen and air to the negative voltage generation stack. This allows the supply of hydrogen and air to the negative voltage generation stack to be controlled.

In the negative voltage release determination step (S1340), the determination unit 130 rechecks the negative voltage sensing information received from the negative voltage sensing unit 120 after a predetermined time has passed after the fuel supply to the negative voltage generation stack is controlled. can do.

In the normal determination step (S1350), if the negative voltage generating stack is not confirmed according to the reconfirmed negative voltage sensing information, the determination unit 130 may determine that the plurality of fuel cell stacks are normal.

In the failure determination step (S1360), when the negative voltage generating stack is confirmed according to the reconfirmed negative voltage sensing information, the determination unit 130 may determine that the plurality of fuel cell stacks are malfunctioning. The control unit 140 may stop supplying fuel to the fuel cell stack according to the failure determination result of the determination unit 130 and notify the outside of the failure of the fuel cell stack so that quick follow-up measures can be taken.

The above description is merely an illustrative explanation of the technical idea of the present invention, and various modifications, changes, and substitutions can be made by those skilled in the art without departing from the essential characteristics of the present invention. will be. Accordingly, the embodiments disclosed in the present invention and the attached drawings are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments and the attached drawings. .

Steps and/or operations according to the invention may occur simultaneously in different embodiments, in different orders, in parallel, for different epochs, etc., as would be understood by those skilled in the art. You can.

Depending on the embodiment, some or all of the steps and/or operations may include executing instructions, programs, interactive data structures, clients and/or servers stored on one or more non-transitory computer-readable media. At least a portion may be implemented or performed using one or more processors. The one or more non-transitory computer-readable media may illustratively be software, firmware, hardware, and/or any combination thereof. Additionally, the functionality of the “modules” discussed herein may be implemented in software, firmware, hardware, and/or any combination thereof.

100: fuel control device
110: Voltage sensing unit
111: first voltage sensing circuit
113: second voltage sensing circuit
115: Third voltage sensing circuit
117: Fourth voltage sensing circuit
120: Negative voltage sensing unit
121: First negative voltage sensing circuit
123: Second negative voltage sensing circuit
125: Third negative voltage sensing circuit
127: Fourth negative voltage sensing circuit
130: Judgment unit
140: control unit
150: Power supply unit
160: Department of Communications
200: Fuel cell stack
210: First fuel cell stack
220: Second fuel cell stack
230: Third fuel cell stack
240: Fourth fuel cell stack

Claims (8)

A voltage sensing unit including a plurality of voltage sensing circuits that sense the voltage of each of the plurality of fuel cell stacks;
a negative voltage sensing unit including a plurality of negative voltage sensing circuits that sense the negative voltage of each of the plurality of fuel cell stacks;
When a negative voltage is generated in at least one of the plurality of fuel cell stacks, a determination unit that receives negative voltage sensing information from the negative voltage sensing unit and determines a negative voltage generating stack using the negative voltage sensing information; and
a control unit that controls a fuel supply system that supplies fuel to the plurality of fuel cell stacks in consideration of the determination result of the determination unit;
Including,
Each of the plurality of negative voltage sensing circuits includes a negative voltage detection unit that senses the negative voltage of each of the plurality of fuel cell stacks,
The negative voltage detection unit,
A first inductor, a second inductor, a first capacitor, a second capacitor, a ground resistor connected to the positive voltage terminal of each of the plurality of fuel cell stacks, a first resistor connected to the first inductor, and a first resistor connected to the second inductor. a second resistor, a Zener diode connected to the first capacitor, and a MOSFET element whose gate terminal is connected to the ground resistor, a drain terminal connected to the second resistor, and a source terminal connected to the Zener diode. A fuel cell control device having a negative voltage detection function, characterized in that: According to claim 1,
A fuel cell control device with a negative voltage detection function, wherein the plurality of voltage sensing circuits are connected to each other in communication in a daisy chain manner. According to claim 1,
Each of the plurality of negative voltage sensing circuits,
A fuel cell control device having a negative voltage detection function, further comprising a signal transmission unit that transmits negative voltage sensing information from the negative voltage detection unit to the determination unit. According to claim 3,
A fuel cell control device having a negative voltage detection function, wherein the first resistor, the second capacitor, the Zener diode, and the MOSFET element are connected to a photocoupler. According to claim 4,
The signal transmission unit,
A negative voltage comprising a positive voltage source connected to the photocoupler, a pull-down resistor connected between the photocoupler and the ground, a third capacitor connected in parallel to the pull-down resistor, and an output terminal connected to the determination unit. A fuel cell control device with a detection function. According to claim 3,
The plurality of negative voltage sensing circuits,
A fuel cell control device having a negative voltage detection function, wherein the plurality of fuel cell stacks are connected in parallel to sense the negative voltage of each fuel cell stack. According to claim 3,
The judgment department,
Characterized by comprising a plurality of signal dividing units for dividing the negative voltage detection signals of each of the plurality of negative voltage sensing circuits, and a signal amplifying unit for amplifying the negative voltage detection signals divided by the plurality of signal dividing units. Fuel cell control device with negative voltage detection function. According to claim 7,
The judgment department,
A fuel cell control device having a negative voltage detection function, characterized in that converting the level of the signal amplified by the signal amplifier into bits and determining a negative voltage generation stack using the converted bits.

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