Power control device for fuel cell vehicle, power control method and power system for fuel cell vehicle comprising this power control device

Abstract

An embodiment of a power control device for a fuel cell vehicle includes a first relay connected to a fuel cell stack, a second relay selectively connected to an external charger, a converter connected to the first relay and the second relay, the converter being configured to convert a first electric power supplied thereto via the first relay into a first demand electric power, convert a second electric power supplied thereto via the second relay into a second demand electric power, and supply the first demand electric power or the second demand electric power to a power consumption device, and a controller configured to control the first relay, the second relay, and the converter.

Description

TECHNICAL FIELDThe present invention relates to power control for a fuel cell vehicle, a power control method, and a power system for a fuel cell vehicle including the power control device.BACKGROUNDHydrogen fuel cell vehicles currently mass-produced use a hydrogen fuel cell and a high voltage battery as a power source. In such a hydrogen fuel cell vehicle, power generated by the hydrogen fuel cell is boosted by a fuel cell DC-DC converter disposed between the hydrogen fuel cell and the high voltage battery, and the boosted power is then supplied to an engine system or used for charging the high voltage battery.Excessive use of the high voltage battery may result in a failure in driving operation of the electric vehicle (EV) or an initial ignition of the fuel cell using the high voltage battery, and as a result, a failure in vehicle operation may occur.In order to prevent a failure of the vehicle operation that may occur due to shortage of power in the high voltage battery, it is necessary to stably maintain a state of charge (SOC) of the high voltage battery by additionally charging the high voltage battery.Therefore, much research is required for stably maintaining the SOC of a high voltage battery for a fuel cell vehicle.The above-described background art is technical information available to the inventors of the embodiments of the present invention to develop embodiments of the present invention or obtained during the development of the embodiments of the present invention, and need not necessarily be regarded as the prior art disclosed to the public before filing the application.ILLUSTRATIONThe present invention relates to a power controller for a fuel cell vehicle, a power control method thereof, and a power system for a fuel cell vehicle including the power control device. Specific embodiments relate to a power control device for a fuel cell vehicle capable of charging a high voltage battery using a fuel cell stack and an external charger, a power control method thereof, and a power system for a fuel cell vehicle including the power control device.Therefore, embodiments of the present invention have been made in view of the problems of the related art, and an embodiment of the present invention provides a power control device for a fuel cell vehicle capable of charging a high voltage battery using a fuel cell stack, a power control method thereof, and a power system for a fuel cell vehicle including the power control device.Another embodiment of the present invention provides a power control device for a fuel cell vehicle capable of charging a high voltage battery using an external charger (for example, a quick charger), a power control method thereof, and a power system for a fuel cell vehicle including the power control device.Another embodiment of the present invention provides a power control device for a fuel cell vehicle capable of charging a high voltage battery using a fuel cell stack and an external charger, a power control method thereof, and a power system for a fuel cell vehicle including the power control device.Another embodiment of the present invention provides a power control device for a fuel cell vehicle capable of charging a high voltage battery using a fuel cell stack and an external charger without adding a separate power converter, a power control method thereof, and a power system for a fuel cell vehicle including the power control device.Embodiments of the present invention are not limited to the above-described embodiments, and other embodiments of the present invention not yet described will be more fully understood by those skilled in the art from the following detailed description.According to an embodiment of the present invention, the above and other features can be achieved by providing a power control device for a fuel cell vehicle capable of charging a high voltage battery using a fuel cell stack and an external charger, a power control method thereof, and a power system for a fuel cell vehicle having the power control device.In an embodiment of the present invention, there is provided a power control device for a fuel cell vehicle, including a first relay connected to a fuel cell stack, a second relay selectively connected to an external charger, a converter connected to the first relay and the second relay, and a controller configured to control the first relay, the second relay, and the converter.According to an embodiment, the converter may convert a first electric power supplied thereto via the first relay into a first demand electric power, a second electric power supplied thereto via the second relay into a second demand electric power, and then supply the first demand electric power and the second demand electric current to a power consumption device.According to an embodiment, the second relay may turn off when the first relay turns on and the second relay may turn on when the first relay turns off, thereby causing the first electric power and the second electric power not to be simultaneously input to the converter.According to an embodiment, the controller may turn on the first relay, turn off the second relay, and control the converter to convert the first electric power to the first demand electric power.According to an embodiment, the controller may turn off the first relay, turn on the second relay, and control the converter to convert the second electric power to the second demand electric power.According to an embodiment, the converter may supply the first demand electric power to a high voltage battery and a motor system.According to an embodiment, the converter may supply the second demand electric power to a high voltage battery.According to an embodiment, the controller may turn off the first relay and turn on the second relay when it is determined that a current state is a vehicle ignition-off state and a current mode is a rapid charging mode based on vehicle-related information input to the controller from the outside.According to an embodiment, the controller may turn on the first relay and turn off the second relay when it is determined that a current state is a vehicle-ignition-on state based on vehicle-related information input to the controller from the outside and a current mode is a fuel cell electric vehicle (FCEV) mode.According to an embodiment, the controller may control the converter to be not driven when it is determined that a current state is a vehicle ignition on state based on vehicle related information input from the outside and a current mode is not a fuel cell electric vehicle (FCEV) mode.In another embodiment of the present invention, there is provided a power control method for a fuel cell vehicle, including converting a first electric power supplied to the converter via a first relay connected to a fuel cell stack into a first demand electric power by a converter, converting a second electric power supplied to the converter via a second relay selectively connected to an external charger into a second demand electric power by the converter, and supplying the first demand electric power or the second demand electric power by the converter to a power consumption device.According to an embodiment, converting the first electric power to the first demand electric power may include turning on the first relay by the controller, turning off the second relay by the controller, and controlling the converter to convert the first electric power to the first demand electric power by the controller.According to an embodiment, converting the second electric power to the second demand electric power may include turning off the first relay by the controller, turning on the second relay by the controller, and controlling the converter to convert the second electric power to the second demand electric power by the controller.According to an embodiment, the supplying may include supplying the first demand electric power to a high voltage battery and a motor system.According to an embodiment, the supplying may include supplying the second demand electric power to a high voltage battery.According to an embodiment, the power control method may further include determining, by the controller, the controller for the first relay, the second relay, and the converter based on vehicle-related information input to the controller from the outside.According to an embodiment, the determining may include turning on the first relay and turning off the second relay when it is determined that a current state is a vehicle ignition on state and a current mode is a fuel cell electric vehicle (FCEV) mode.According to an embodiment, the determining may include turning off the first relay and turning on the second relay when it is determined that a current state is a vehicle ignition-off state and a current mode is a fast charging mode.According to one embodiment, the determining may include controlling the converter to be non-driven when it is determined that a current state is a vehicle ignition on state and a current mode is not a fuel cell electric vehicle (FCEV) mode.In another embodiment of the present invention, there is provided a power control system for a fuel cell vehicle, including a power control device including a first relay, a second relay, a converter connected to one end of the first and second relays, and a controller, a fuel cell stack connected to another end of the first relay, an external charger selectively connected to another end of the second relay, and a high voltage battery configured to receive electric power from the converter.According to an embodiment, the converter may convert a first electric power supplied thereto via the first relay into a first demand electric power, convert a second electric power supplied thereto via the second relay into a second demand electric power, and then supply the first demand electric power and the second demand electric power to a power consumption device.Detailed information according to various embodiments of the present invention except for solutions to the problems described above is included in the following description and the accompanying drawings.The problems to be solved and the solutions to the above described problems are not to be understood as essential features of the claims. Accordingly, the scope of the claims is not limited by the terms described in the content of the present application.BRIEF DESCRIPTION OF THE DRAWINGSThe above and other objects, features and other advantages of embodiments of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings: FIG. 1 is a diagram showing the configuration of a power system for a fuel cell vehicle according to an embodiment of the present invention; FIG. 2 is a diagram showing a detailed configuration of a converter of a power control device for a fuel cell vehicle according to an embodiment of the present invention; FIG. 3 is a diagram showing a detailed configuration of a controller of the power control device for the fuel cell vehicle according to an embodiment of the present invention; FIG. 4 is a diagram illustrating the states of the first and second relays according to the control of a control signal output circuit in an embodiment of the present invention; and FIG. 5 is a flowchart for explaining a power control method for a fuel cell vehicle according to an embodiment of the present invention.DETAILED DESCRIPTION OF EMBODIMENTSThe advantages, features, and methods for achieving the same of embodiments of the present invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to a plurality of the embodiments described below, and may be implemented in various forms. The embodiments of the present invention are provided merely to fully disclose embodiments of the present invention and fully inform a person having ordinary skill in the art to which the present invention pertains of the scope of the present invention. Accordingly, the embodiments of the present invention are defined by the scope of the claims.The shapes, sizes, ratios, angles, numbers, and the like illustrated in the drawings for illustrating the embodiments of the present invention are illustrative only and are not limited to the content illustrated in the drawings. Wherever possible, the same reference numbers will be used in the drawings to refer to the same or like parts. In the following description, detailed descriptions of technologies or configurations related to embodiments of the present invention may be omitted so as not to unnecessarily obscure the subject matter of the embodiments of the present invention. In the description, when terms such as "including", "having", and "comprising" are used, an additional component may be present unless "only" is used. A component described in the singular also includes components in the plural part unless expressly stated otherwise.It should be interpreted that the components included in the embodiments of the present invention include a range of errors, although there is no additional concrete description in this respect.In describing a plurality of embodiments of the present invention, when describing a temporal relationship, for example, when using terms for a temporal relationship of events such as "after", "subsequently", "next", and "before", there may also be a case that the events are not continuous unless "immediately" or "immediately" is used.Meanwhile, although terms having an ordinal number such as first or second may be used to describe a plurality of constituent elements, the constituent elements are not limited to the terms, and the terms are used only for the purpose of distinguishing one constituent element from other constituent elements. Accordingly, a first component described below may be referred to as a second component.It should be understood that although the terms first, second, A, B, (a), (b), etc. may be used herein to describe various elements of embodiments of the present invention, these terms are only used to distinguish one element from another element, and need, order, sequence of corresponding elements, numbers, etc. are not limited by these terms. It will be understood that when an element is referred to as being "connected to", "coupled to", or "accessible to" another element, an element may be "connected to", "coupled to", or "accessible to" another element via another element, although an element may be directly connected to another element or directly accessible to another element.The term "at least one" is to be understood to include all combinations of one or more of the listed items. For example, the meaning of "at least one of a first, a second, and a third element" refers to the combination of all elements suggested by two or more of the first, the second, and the third element, and the first, the second, or the third element.The following embodiments may be partially or wholly coupled or combined with each other, and may be technically connected and implemented in various ways. The embodiments may be realized independently of each other or in a co-dependent relationship.Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Moreover, the scales of the constituent elements illustrated in the drawings may deviate from the actual scales for convenience of description. That is, the scales of the constituent elements shown in the drawings need not coincide with the scales shown in the drawings.Hereinafter, a power control device for a fuel cell vehicle according to an embodiment of the present invention, a power control method thereof, and a power system for a fuel cell vehicle including the power control device will be described with reference to the accompanying drawings.FIG. 1 is a diagram illustrating a configuration of a power system 1 for a fuel cell vehicle according to an embodiment of the present invention.Referring to FIG. 1, the power system 1 according to the present invention may include a fuel cell stack 100, a high voltage battery 200, an external charger 300, a power control device 400, and a motor system 500.According to an embodiment, the fuel cell stack 100 (or a first energy storage device or a first energy supplier) may provide and output a first electric power (or first electric energy) by a chemical reaction between oxygen and hydrogen.The first electric power of the fuel cell stack 100 may be supplied to the engine system 500 or the high voltage battery 200 via the power control device 400.In other words, the first electric power of the fuel cell stack 100 may be used to drive a motor 510 or charge the high voltage battery 200.For example, a fuel cell of the fuel cell stack 100 may be, but is not limited to, a polymer electrolyte membrane fuel cell (PEMFC) or a proton exchange membrane fuel cell (PEMFC).According to an embodiment, the high voltage battery 200 (or a second energy storage device or a second energy supply device) may supply second electric power (or second electric energy, respectively).The high voltage battery 200 may be charged by the first electric power supplied from the power control device 400. Moreover, the high voltage battery 200 may receive a third electric power (or third electric power) output from the external charger 300 via the power control device 400, and may be charged with the third electric power.The second electric power supplied from the high voltage battery 200 may be supplied to the fuel cell stack 100 by the power control device 400 and used as such for igniting (or driving) the fuel cell stack 100.According to an embodiment, the external charger 300 (or a third power storage device or a third power supply device) is a power supply source installed outside the fuel cell vehicle without being installed in the fuel cell vehicle. The external charger 300 may be, for example, a quick charger (or a high-speed charger).When the external charger 300 is connected to the power control device 400, the external charger 300 may be included in the power system 1 for the fuel cell vehicle according to an embodiment of the present invention, and as such, supply the third electric power (or the third electric power) to the power control device 400 side.The third electric power supplied from the external charger 300 may be supplied to the high voltage battery 200 via the power control device 400. In other words, the third electric power supplied from the external charger 300 may be used for charging the high voltage battery 200.According to an embodiment, the power control device 400 may perform the electric power processing in the fuel cell vehicle.If necessary, the power control device 400 may suitably convert the electric power (or electric power) supplied thereto from the outside. The power control device 400 may distribute introduced electric power and then transmit the distributed electric power to other configurations in the fuel cell vehicle.According to an embodiment, the power control device 400 may receive the first electric power supplied from the fuel cell stack 100 and supply the received first electric power to the high voltage battery 200 to charge the high voltage battery 200, or the power control device 400 may supply the received first electric power to the motor system 500 to drive the motor system 500.According to an embodiment, the power control device 400 may receive the second electric power supplied from the high voltage battery 200 and supply the received second electric power to the fuel cell stack 100 to operate the fuel cell stack 100.According to an embodiment, the power control device 400 may receive the third electric power supplied from the external charger 300 and supply the received third electric power to the high voltage battery 200 to charge the high voltage battery 200.For example, the power control device 400 may be connected to the fuel cell stack 100 via a first terminal CT 1 (or a fuel cell terminal) and to the external charger 300 via a second terminal CT 2 (or a charger terminal).According to an embodiment, the power control device 400 may include a first relay (Relay_ 1) R_ 1, a second relay (Relay_ 2) R_ 2, a converter 410, and a controller 420.The first relay R_ 1 may be disposed on a first input side of the converter 410 and between the fuel cell stack 100 and the converter 410. For example, the first relay R_ 1 may be disposed between the converter 410 and the first terminal CT 1. Accordingly, one end of the first relay R_ 1 may be connected to the converter 410, and the other end of the first relay R_ 1 may be connected to the fuel cell stack 100 while being connected to the first terminal CT 1.The first relay R_ 1 may be turned on or off under the control of the controller 420, and may selectively connect the fuel cell stack 100 and the converter 410 to each other in response to a first control signal CS 1 of the controller 420.The second relay R_ 2 may be disposed on a second input side of the converter 410 and between the external charger 300 and the converter 410. For example, the second relay R_ 2 may be disposed between the converter 410 and the second terminal CT 2. Accordingly, one end of the second relay R_ 2 may be connected to the converter 410, and the other end of the second relay R_ 2 may be selectively connected to the external charger 300 while being connected to the second terminal CT 2.The second relay R_ 2 may be turned on or off under the control of the controller 420, and may selectively connect the external charger 300 and the converter 410 to each other in response to a second control signal CS 2 of the controller 420.The converter 410 may operate in response to a third control signal CS 3, and thus convert the electric power supplied thereto into demand electric power, and then output the demand electric power.According to an embodiment, the converter 410 may be a fuel cell direct current (FDC) converter (or a high voltage boost direct current (DC-DC) converter).In response to control of the controller 420, the converter 410 may convert the first electrical power introduced at a first input thereof to a first demand electrical power and then output the first demand electrical power. The first demand electric power may be supplied to the high voltage battery 200 or the motor system 500 via a third terminal CT 3.In this case, the converter 410 may receive the first electric power from the fuel cell stack 100 via the first relay R_ 1. The first required electric power may be electric power for driving the motor 510.In response to control of the controller 420, the converter 410 may convert the second electric power supplied from the high voltage battery 200 into a second required electric power, and then output the second required electric power. The second demand electric power may be supplied to the fuel cell stack 100.In this case, the second required electric power may be electric power required for driving the fuel cell stack 100.In response to control of the controller 420, the converter 410 may convert the third electrical power introduced at a second input thereof to a third demand electrical power and then output the third demand electrical power. The third required power may be supplied to the high voltage battery 200.In this case, the converter 410 may receive the third electric power output from the external charger 300 via the second relay R_ 2. The third required electric power may be electric power for charging the high voltage battery 200.The controller 420 may control the overall operation of the power control device 400 and control the first relay R_ 1, the second relay R_ 2, and the converter 410, thereby enabling the converter 410 to supply required electric power to a power consumption device.For example, the controller 420 may control the first relay R_ 1, the second relay R_ 2, and the converter 410 based on information on the on / off state of the vehicle ignition and vehicle mode information input thereto from the outside.According to an embodiment, the controller 420 may output a fourth control signal CS 4 for controlling the operation of an inverter 520 of the motor system 500.According to an embodiment, the motor system 500 may drive a motor by means of electric power supplied from the power control device 400.The motor system 500 may include, for example, a motor 510 and the inverter 520 that converts the electric power supplied from the power control device 400 into the electric power required for driving the motor 510, thereby driving the motor 510.According to an embodiment, the inverter 520 may convert a voltage input thereto from the power control device 400 into a three-phase AC voltage via a semiconductor switching element based on a fourth control signal CS 4 applied from the controller 420, thereby driving the motor 510.According to the above-described embodiment of the present invention, it may be possible to charge the high-voltage battery 200 not only by the fuel cell stack 100, but also to charge the high-voltage battery 200 by the external charger 300.In addition, driving (or igniting) the fuel cell stack 100, charging of the high-voltage battery 200 by the fuel cell stack 100, charging of the high-voltage battery 200 by the external charger 300, and supplying power to the engine system 500 may be achieved by a power control device 400.FIG. 2 is a diagram showing a detailed configuration of the converter 410 of the power control device 400 for the fuel cell vehicle according to an embodiment of the present invention. FIG. 3 is a diagram showing a detailed configuration of the controller 420 of the power control device 400 for the fuel cell vehicle according to an embodiment of the present invention.Next, the power control device 400 for the fuel cell vehicle according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3.According to an embodiment of the present invention, the converter 410 may include, but is not limited to, a power conversion module 411, a current sensor unit 412, a coil unit 413, a first capacitor C 1, and a second capacitor C 2.According to an embodiment of the present invention, the controller 420 may include, but is not limited to, a control signal output circuit 421, a current detection circuit 422 and a voltage detection circuit 423.The power conversion module 411 may include a plurality of switching elements SW 1 to SW 6 configured to switch according to a third control signal CS 3 output from the control signal output circuit 421.The third control signal CS 3 may include, for example, a plurality of pulse width modulation (PWM) PWM 1 to PWM 6 signals for controlling the plurality of switching elements SW 1 to SW 6.For example, each of the plurality of switching elements SW 1 to SW 6 included in the power conversion module 411 may be an insulated gate bipolar transistor (IGBT) or a silicon carbide field effect transistor (SiC FET).The power conversion module 411 may convert the electric power supplied thereto into required electric power according to the control signal CS 3 of the control signal output circuit 421, and then output the required electric power.The first capacitor C 1 may be connected in parallel to the fuel cell stack 100 and the power conversion module 411 between the fuel cell stack 100 and the power conversion module 411. For example, the first capacitor C 1 may be connected in parallel with the first relay R_ 1 and the power conversion module 411 between the first relay R_ 1 and the power conversion module 411.One end of the first capacitor C 1 may be connected between the first relay R_ 1 and the power conversion module 411, and the other end of the first capacitor C 1 may be connected to the ground.The first capacitor C 1 may filter out a ripple component of a DC voltage input to the power conversion module 411, and thus may prevent a ripple component from being input to the power conversion module 411.Moreover, the first capacitor C 1 can filter out a ripple component of a DC voltage supplied to the fuel cell stack 100 after being output from the power conversion module 411, thereby preventing the ripple component from being introduced into the fuel cell stack 100.The second capacitor C 2 may be connected in parallel to the power conversion module 411 and the high voltage battery 200 between the power conversion module 411 and the high voltage battery 200.One end of the second capacitor C 2 may be connected between the power conversion module 411 and the high voltage battery 200, and the other end of the second capacitor C 2 may be connected to the ground.The second capacitor C 2 may filter out a ripple component of a DC voltage supplied to the high voltage battery 200 after being output from the power conversion module 411, and thus may prevent the ripple component from being supplied to the high voltage battery 200.The current sensor unit 412 may be disposed on the fuel cell stack 100 side of the power conversion module 411 to measure the direct currents Idc 1 to Idc 3 supplied to the power conversion module 411. The current sensor unit 412 may be disposed between the first relay R_ 1 and the power conversion module 411, for example.The coil unit 413 may be disposed on the fuel cell stack 100 side of the power conversion module 411. The coil unit 413 may be arranged in series between the first relay R_ 1 and the power conversion module 411, for example. The coil unit 413 may constitute a filter unit together with the first capacitor C 1, for example.The control signal output circuit 421 may control the first relay R_ 1, the second relay R_ 2, and the power conversion module 411 of the converter 410 based on information on the on / off state of the vehicle ignition and information on the vehicle mode input thereto from the outside.According to an embodiment, the control signal output circuit 421 may turn off the first relay R_ 1 while the second relay R_ 2 is turned on in a vehicle ignition IG OFF state and a fast charge mode.In addition, the control signal output circuit 421 may control the power conversion module 411 to convert the electric power supplied via the second relay R_ 2 into electric power for charging the high voltage battery.Accordingly, the electric power of the external charger 300 may be supplied to the high voltage battery 200 via the second relay R_ 2.According to an embodiment, the control signal output circuit 421 may turn on the first relay R_ 1 while turning off the second relay R_ 2 in a vehicle ignition IG ON state and a fuel cell electric vehicle mode (FCEV).In addition, the control signal output circuit 421 may convert the electric power of the high voltage battery 200 into electric power for ignition of the fuel cell stack 100 by the control of the power conversion module 411, and then supply the converted electric power to the fuel cell stack 100 for ignition of the fuel cell stack 100 (FDC buck mode).Thereafter, the control signal output circuit 421 may convert the electric power output from the fuel cell stack 100 into electric power for motor drive by controlling the power conversion module 411.Moreover, the control signal output circuit 421 may convert the electric power for motor drive into electric power for driving a three-phase motor by controlling the inverter 520 of the motor system 500.Accordingly, the electric power of the fuel cell stack 100 introduced via the first relay R_ 1 may be supplied to the engine system 500 (FCEV mode) and thus charge the high voltage battery 200 connected in parallel between the converter 410 and the engine system 500.According to one embodiment, the control signal output circuit 421 does not perform control for the converter 410 in the vehicle ignition IG ON state and not in the FCEV mode (i.e., an EV mode).For example, the control signal output circuit 421 may turn off both the first and second relays R_ 1 and R_ 2 and may not output the control signal CS 3 to the power conversion module 411.FIG. 4 is a diagram illustrating the states of the first and second relays R_ 1 and R_ 2 according to the control of the control signal output circuit 421 in an embodiment of the present invention.As shown in FIG. 4, the first and second relays R_ 1 and R_ 2 may be maintained in different states when the vehicle is operated in the FCEV mode or the high voltage battery charging mode. On the other hand, the first and second relays R_ 1 and R_ 2 may be maintained in a turned-off state when the vehicle is operated in the EV mode in which FDC traveling is not required.Since the second relay R_ 2 turns off when the first relay R_ 1 turns on and the second relay R_ 2 turns on when the first relay R_ 1 turns off, the electric power of the first relay R- 1 and the electric power of the second relay R_ 2 are not simultaneously input to the converter 410.The current detection circuit 422 may be connected to the current sensor unit 412 and thus obtain the direct currents Idc 1 to Idc 3 measured by the current sensor unit 412.The voltage detection circuit 423 may measure both ends of the first capacitor C 1 and thus obtain a DC voltage Vdc 1 on the low voltage side.Moreover, the voltage detection circuit 423 can measure both ends of the second capacitor C 2 and thus obtain a DC voltage Vdc 2 on the high voltage side.FIG. 5 is a flowchart for explaining a power control method for a fuel cell vehicle according to an embodiment of the present invention.The sequential operations shown in FIG. 5 may be performed by the power control system 1 for the fuel cell vehicle described with reference to FIGS. 1 to 4.Hereinafter, the power control method of the fuel cell vehicle according to an embodiment of the present invention will be mainly described in connection with the operation of the power control device 400 for the fuel cell vehicle.First, the controller 420 may receive vehicle-related information from the outside (for example, from a hybrid controller) (S 500).In step S 500, the vehicle-related information may include information on the on / off state of the vehicle ignition and on the vehicle mode.The controller 420 may determine the control for the first relay R_ 1, the second relay R_ 2, and the converter 410 based on the vehicle-related information input from the outside.Thereafter, the controller 420 may determine whether or not the current state is a state of the vehicle ignition based on the information on the on / off state of the vehicle ignition (S 510).After it is determined in step S 510 that the current state is not the "vehicle ignition on" state (S 510-NO) or the current state is the "vehicle ignition off" state, the controller 420 may determine whether or not a current mode is a rapid charge mode based on the vehicle mode information (S 520).When it is determined in step S 520 that the current mode is not the fast charge mode (S 520-No), the control unit 420 may not perform and then ends a control operation.When it is determined in step S 520 that the current mode is the fast charging mode (S 520-Yes), the controller 420 may charge the high voltage battery 200 with electric power supplied from the external charger 300 connected to the second relay R_ 2 by controlling the first relay R_ 1, the second relay R_ 2, and the power conversion module 411 of the converter 410 (S 530).In step S 530, the controller 420 may turn off the first relay R_ 1 connected to the fuel cell stack 100 and turn on the second relay R_ 2 connected to the external charger 300.In addition, the controller 420 may control the power conversion module 411 of the converter 410 to convert the electric power supplied from the external charger 300 into electric power for charging the high-voltage battery 200.On the other hand, in the determination in step S 510, that the current state is the "vehicle ignition on" state (S 510-Yes), the controller 420 may determine whether or not the current mode is an FCEV mode based on the vehicle mode information (S 540).After it is determined in step S 540 that the current mode is the FCEV mode (S 540-Yes), the controller 420 may supply electric power, which is output from the fuel cell stack 100 connected to the first relay R_ 1, to the motor system 500 by controlling the first relay R_ 1, the second relay R_ 2, and the power conversion module 411 of the converter 410 (S 550).In step S 550, the controller 420 may turn on the first relay R_ 1 connected to the fuel cell stack 100 and turn off the second relay R_ 2.In addition, the controller 420 may control the power conversion module 411 of the converter 410 to convert the electric power of the high voltage battery 200 into electric power for ignition of the fuel cell stack 100, and then supply the converted electric power to the fuel cell stack 100 (S 551). Accordingly, the fuel cell stack 100 may perform the ignition based on the electric power for the ignition of the fuel cell stack.After the fuel cell stack 100 is ignited, the controller 420 may control the power conversion module 411 of the converter 410 to convert the electric power output from the fuel cell stack 100 into electric power for motor drive and then supply the converted electric power to the motor system 500 (S 552). Accordingly, the motor 510 may be driven based on the electric power for motor drive.In this case, the controller 420 may also control the inverter 520 of the motor system 500 in addition to the power conversion module 411 of the converter 410. According to the control by the controller 420, the inverter 520 may convert a voltage supplied thereto from the power conversion module 411 into a three-phase AC voltage to drive the motor 510.When it is determined in step S 540 that the current mode is not the FCEV mode (S 540-No), control may not perform control for the converter 410, and the converter 410 may not be driven (S 560).According to an embodiment of the present invention, it may be possible to provide a power control device for a fuel cell vehicle capable of charging a high voltage battery using a fuel cell stack, a power control method thereof, and a power system for a fuel cell vehicle including the power control device.According to another embodiment of the present invention, it may be possible to provide a power control apparatus for a fuel cell vehicle capable of charging a high voltage battery using an external charger (for example, a quick charger), a power control method thereof, and a power system for a fuel cell vehicle including the power control apparatus.According to another embodiment of the present invention, it may be possible to provide a power control device for a fuel cell vehicle capable of charging a high voltage battery using a fuel cell stack and an external charger, a power control method thereof, and a power system for a fuel cell vehicle including the power control device.According to another embodiment of the present invention, there can be provided an FDC capable of achieving all the tasks of driving a fuel cell stack (or igniting), charging a high-voltage battery via the fuel cell stack, charging a high-voltage battery via an external charger, and supplying electric power to an engine system.Since the FDC, which is a power conversion device having multiple functions (or operations), is provided, it may be possible to achieve the charging of the high-voltage battery by the fuel cell stack and the charging of the high-voltage battery by the external charger without the need to add a separate power converter unless it is an existing FDC.Accordingly, the charging of the high voltage battery by the fuel cell stack and the charging of the high voltage battery by the external charger can be achieved while reducing costs, compared to the case where dedicated power conversion devices are required to be provided for the driving of the fuel cell stack and the charging of the high voltage battery, respectively.Moreover, it may be possible to achieve improvement in durability of the fuel cell stack and improvement in fuel consumption of the fuel cell vehicle by cooperative control of the power control device for the fuel cell vehicle and a fuel cell control unit (FCU) according to each of the embodiments of the present invention.In a situation where an infrastructure associated with a quick charger is expanded, it is expected that the power control apparatus for the fuel cell vehicle according to each of the embodiments of the present invention can be very useful and effectively used in the field of the fuel cell vehicles.The effects achievable in embodiments of the present invention are not limited to the effects described above, and other effects of embodiments of the present invention not described yet will be better understood by a person skilled in the art from the appended claims.Although embodiments of the present invention will be described in detail with reference to the accompanying drawings, the embodiments of the present invention are not limited to the embodiments, and various changes may be made in the embodiments without departing from the principles and spirit of the invention. Therefore, the disclosed embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the embodiments of the invention is defined by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalence of the embodiments of the invention are intended to be embraced therein.

Claims

A power control device for a fuel cell vehicle, the device comprising: a first relay connected to a fuel cell stack; a second relay selectively connected to an external charger; a converter connected to the first relay and the second relay, the converter configured to convert a first electric power supplied thereto via the first relay into a first required electric power, convert a second electric power supplied thereto via the second relay into a second required electric power, and supply the first required electric power or the second required electric power to a power consumption device; and a controller configured to control the first relay, the second relay, and the converter.The apparatus of claim 1, wherein the second relay is configured to turn off when the first relay turns on and the second relay is configured to turn on when the first relay turns off, such that the first electrical power and the second electrical power are not simultaneously introduced into the converter.The apparatus of claim 1, wherein the controller is configured to turn on the first relay, turn off the second relay, and control the converter to convert the first electric power to the first demand electric power.The apparatus of claim 1, wherein the controller is configured to turn off the first relay, turn on the second relay, and control the converter to convert the second electric power to the second demand electric power.The apparatus of claim 1, wherein the power consumption device comprises a high voltage battery and a motor system, and wherein the converter is configured to supply the first demand electric power to the high voltage battery and the motor system.The apparatus of claim 1, wherein the power consumption device comprises a high voltage battery, and wherein the converter is configured to supply the second demand electric power to the high voltage battery.The apparatus of claim 1, wherein the controller is configured to, based on a determination that a current state is a vehicle ignition-off state based on vehicle-related information input to the controller from the outside and a current mode is a rapid charging mode, turn off the first relay and turn on the second relay.The apparatus of claim 1, wherein the controller is configured to switch on the first relay and switch off the second relay based on a determination that a current state based on vehicle related information input from the outside to the controller is a vehicle ignition on state and a current mode is a fuel cell electric vehicle (FCEV) mode.The apparatus of claim 1, wherein the controller is configured to control the converter to be not driven based on a determination that a current state is a vehicle ignition on state based on vehicle related information input to the controller from the outside and a current mode is not a fuel cell electric vehicle (FCEV) mode.A power control method for a fuel cell vehicle, the method comprising: converting a first electric power introduced into a converter via a first relay connected to a fuel cell stack into a first demand electric power; converting a second electric power introduced into the converter via a second relay selectively connected to an external charger into a second demand electric power; and supplying the first demand electric power or the second demand electric power to a power consumption device.The method of claim 10, wherein the second relay turns off when the first relay turns on and the second relay turns on when the first relay turns off, such that the first electrical power and the second electrical power are not simultaneously introduced into the converter.The method of claim 10, wherein converting the first electrical power to the first demand electrical power comprises turning on the first relay, turning off the second relay, and controlling the converter to convert the first electrical power to the first demand electrical power.The method of claim 10, wherein converting the second electrical power to the second demand electrical power comprises turning off the first relay, turning on the second relay, and controlling the converter to convert the second electrical power to the second demand electrical power.The method of claim 10, wherein the power consumption device comprises a high voltage battery and a motor system, and wherein supplying the first demand electric power or the second demand electric power to the power consumption device comprises supplying the first demand electric power to the high voltage battery and the motor system.The method of claim 10, wherein the power consumption device comprises a high voltage battery, and wherein supplying the first demand electric power or the second demand electric power to the power consumption device comprises supplying the second demand electric power to the high voltage battery.The method of claim 10, further comprising determining control for the first relay, the second relay, and the converter based on vehicle-related information input to a controller from the outside.The method of claim 16, wherein determining the controller comprises turning on the first relay and turning off the second relay when it is determined that a current state is a vehicle ignition on state and a current mode is a fuel cell electric vehicle (FCEV) mode.The method of claim 16, wherein determining the controller comprises turning off the first relay and turning on the second relay when it is determined that a current state is an ignition-off state and a current mode is a fast charging mode.The method of claim 16, wherein determining the controller comprises controlling the converter to be non-driven when it is determined that a current state is a vehicle ignition on state and a current mode is not a fuel cell electric vehicle (FCEV) mode.A power control system for a fuel cell vehicle, the system comprising: a power control device comprising: a first relay; a second relay; a converter connected to a first end of each of the first and second relays, the converter configured to convert a first electric power supplied thereto via the first relay into a first demand electric power, convert a second electric power supplied thereto via the second relay into a second demand electric power, and supply the first demand electric power or the second demand electric power to a power consumption device, the power consumption device comprising a high voltage battery; and a controller configured to control the first relay, the second relay, and the converter; a fuel cell stack connected to a second end of the first relay; and an external charger selectively connected to a second end of the second relay.

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