JP4790781B2 - Fuel cell vehicle - Google Patents

Description

  The present invention includes a fuel cell and a power storage device that stores power, etc. from the fuel cell, and is used as a power supply source for starting the fuel cell, and the amount of power stored in the power storage device in winter The present invention relates to a fuel cell vehicle that increases the fuel consumption.

  For example, a polymer electrolyte fuel cell is an electrolyte / electrode in which an anode side electrode and a cathode side electrode are arranged opposite to each other on both sides of an electrolyte (electrolyte membrane) made of a polymer ion exchange membrane (cation exchange membrane). A power generation cell in which the structure is sandwiched between separators is provided. This type of fuel cell is normally used as a fuel cell stack by stacking a predetermined number of power generation cells.

  In this power generation cell, a fuel gas supplied to the anode electrode, for example, a gas mainly containing hydrogen (hereinafter also referred to as a hydrogen-containing gas) is ionized with hydrogen on an electrode catalyst, and is cathoded through an electrolyte. Move to the side electrode side. Electrons generated during that time are taken out to an external circuit and used as direct current electric energy. The cathode side electrode is supplied with an oxidant gas, for example, a gas mainly containing oxygen or air (hereinafter also referred to as an oxygen-containing gas). Electrons and oxygen react to produce water.

  In the power generation cell, a reaction gas channel for flowing a reaction gas is provided in the plane of the separator so as to face each electrode, and the power generation cell is cooled between separators constituting adjacent power generation cells. A cooling medium flow path for flowing the cooling medium is provided. The reactive gas is an oxidant gas and a fuel gas, and the reactive gas flow path is an oxidant gas flow path for flowing the oxidant gas facing the cathode side electrode, and a fuel gas facing the anode side electrode. And a fuel gas flow path for flowing gas.

  By the way, there has been proposed a fuel cell vehicle (hybrid power vehicle) that drives a motor for driving a vehicle using a fuel cell system that uses both a fuel cell and a high voltage battery as a power source. In this fuel cell vehicle, the vehicle (fuel cell) is activated using the electric power of the battery and the vehicle travel and auxiliary power are assisted, or so-called EV (Electric Vehicle) travel is performed only with the battery power.

  Such a fuel cell vehicle is configured to store necessary power in a battery when the vehicle is stopped in order to reliably restart the vehicle (Patent Documents 1 and 2).

  In Patent Document 1, the minimum outside air temperature is predicted from the positioning data of the vehicle position by GPS radio waves and the date data, and the required power of the battery is predicted based on the prediction result.

  In Patent Document 2, the battery temperature at restart is predicted based on the outside air temperature, and the required power of the battery is predicted based on the predicted battery temperature.

JP 2004-146075 A JP 2007-31309 A

  However, in the technologies according to Patent Documents 1 and 2, the battery temperature at the time of restart is obtained by prediction, and the battery charge amount at the time of stop cannot be determined accurately.

  In addition, in the technique according to Patent Document 1, since a positioning data receiver such as GPS is an indispensable constituent requirement, the outside air temperature cannot be predicted in an environment where radio waves cannot be received, such as in a garage.

  Furthermore, in the technology according to Patent Document 2, the outside air temperature is detected by the temperature sensor when the vehicle is started. However, when the vehicle is started, the outside air temperature detected by the temperature sensor changes abruptly. The accuracy of the detected temperature (outside air temperature) to be detected is lowered.

  The present invention has been made in consideration of such problems, and it is possible to accurately determine the outside air temperature for determining the amount of charge that secures the required power of the power storage device at the time of stopping without predicting the outside air temperature. An object of the present invention is to provide a fuel cell vehicle that can be detected well and enables accurate winter season determination.

  A fuel cell vehicle according to the present invention includes a fuel cell that generates electricity by a reaction between hydrogen gas and oxidant gas, a power storage device that stores electric power from the fuel cell, a temperature sensor mounted on the vehicle, and a vehicle start-up. A fuel cell vehicle comprising: a startup required power increase unit that increases the required power of the vehicle in winter; and a stop charge amount determination unit that determines a charge amount of the power storage device when the vehicle is stopped so as to ensure the required power And determining whether the temperature detected by the temperature sensor is equal to or lower than a predetermined temperature after the vehicle stops, and determining the winter season when the temperature is equal to or lower than the predetermined temperature; and the detection by the temperature sensor after the vehicle stops The determination by the winter determination unit is prohibited until the temperature is estimated to follow the outside air temperature, and when it is estimated that the temperature follows the outside air temperature, the determination by the winter determination unit is performed. And having a winter determination prohibition and canceling unit for canceling the prohibition of the.

  According to the present invention, the winter determination prohibition / cancellation unit determines whether the temperature detected by the temperature sensor follows the outside air temperature after the vehicle stops, until the winter determination unit determines (the temperature detected by the temperature sensor after the vehicle stops). When the temperature detected by the temperature sensor is estimated to follow the outside air temperature, the determination by the winter determination unit is canceled.

  In the present invention, since the outside air temperature is obtained from the measured value of the temperature sensor without predicting the outside air temperature, the outside air temperature for determining the amount of charge for securing the required power of the power storage device at the time of stopping is accurately determined. Can be detected.

  In the winter determination prohibition / cancellation unit, the condition that the temperature detected by the temperature sensor follows the outside air temperature after the vehicle stops is that the temperature sensor is set at regular intervals after a predetermined time has elapsed since the vehicle stopped. When the temperature is detected by the above, when the temperature change amount in the predetermined time becomes smaller than a predetermined value, or when the detected temperature after the predetermined time elapses is higher than the detected temperature before the predetermined time, the temperature It is estimated that the temperature detected by the sensor follows the outside air temperature.

  According to the present invention, it is possible to accurately detect the outside air temperature for determining the amount of charge for securing the necessary power of the power storage device at the time of stopping without predicting the outside air temperature, and to perform accurate winter judgment. .

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a fuel cell vehicle 12 to which an embodiment of the present invention is applied.

  This fuel cell vehicle 12 basically includes a hybrid power source including a fuel cell 14 and a power storage device (battery) 16 serving as an energy storage for assisting the power generation output of the fuel cell 14, and the hybrid power source. A traveling drive motor 18 is supplied with current (electric power) from a power source supplied through an inverter (not shown). As the battery 16, for example, a lithium ion secondary battery, a nickel metal hydride secondary battery, or a capacitor can be used.

  The current output of the fuel cell 14 is connected to one end side of a VCU (Voltage Control Unit) 20 and the motor 18 through the wiring 101. Connected to the wiring 102 on the other end side of the VCU 20 are a battery 16, an air conditioner (referred to as an air conditioner) 22, an air compressor (referred to as an air compressor) 24, a cooling water pump 26, a DT cooling water pump 28, and the like. Has been.

  The VCU 20 is, for example, a bidirectional DC / DC converter, which converts the power of the battery 16 into a voltage and supplies it to the motor 18, and converts the power of the fuel cell 14 and / or the regenerative power of the motor 18 into a voltage. 16 is supplied for charging and supplied to the air compressor 24 and the like.

  That is, the VCU 20 performs voltage conversion between a high voltage (voltage of the fuel cell 14) appearing on the wiring 101 and a low voltage (voltage of the battery 16) appearing on the wiring 102, and is connected between both ends of the VCU 20. Controls the input and output of power between electrical loads.

  The electric power of the fuel cell 14 and the battery 16 is called a drive system device {DT (Drive Train) system device. } And 30 are supplied to the DT cooling water pump 28 and the cooling water pump 26 that cools the fuel cell 14.

  In this embodiment, the DT system device 30 includes a motor 18, a VCU 20, an air conditioner 22, and an air compressor 24.

  These DT devices 30 are cooled through the cooling liquid by a DT radiator 34 and a DT cooling water pump 28 communicating with the cooling water flow path 32.

  The fuel cell 14 is cooled through the cooling liquid by an FC (Fuel Cell) radiator 38 and a cooling water pump 26 communicating with the cooling water flow path 36.

  The DT radiator 34 and the FC radiator 38 exchange heat through a wind 39 (referred to as vehicle speed wind) by outside air having a wind speed corresponding to the vehicle speed.

  The fuel cell 14 has a stack structure in which a plurality of fuel cell units configured by holding a solid polymer electrolyte membrane between an anode electrode and a cathode electrode are stacked and integrated. Each fuel cell includes an electrolyte membrane (solid polymer electrolyte membrane) and a metal separator that holds the electrode structure. An oxidant gas channel (also referred to as a reaction gas channel) is provided on the surface of one separator facing the cathode electrode of the electrolyte membrane / electrode structure. A fuel gas passage (also referred to as a reaction gas passage) is formed on the surface of the other separator facing the anode electrode of the electrolyte membrane / electrode structure.

A fuel gas, for example, hydrogen (H ₂ ) is supplied to the fuel gas passage of the fuel cell 14 from the fuel supply system 46 through the fuel gas supply passage 44. In the fuel supply system 46, on / off of the shut-off valve is controlled by the control unit 100.

  The gas containing unused hydrogen gas discharged from the fuel gas passage of the fuel cell 14 is returned to the fuel gas supply passage 44 through the fuel gas circulation passage 48. The fuel gas supply channel 44 is provided with an ejector (not shown), and the gas from the fuel gas circulation channel 48 is returned to the fuel gas channel of the fuel cell 14 by the negative pressure generated by the ejector.

  Compressed air is supplied to the oxidant gas flow path of the fuel cell 14 from the air compressor 24 through the oxidant gas supply flow path 50, and the compressed air passes through the oxidant gas flow path of the fuel cell 14 and communicates therewith. The oxidant gas discharge channel 52 is discharged to the outside air.

  The fuel cell vehicle 12 has various temperature sensors for controlling electric loads such as the DT system device 30 including the motor 18 and the air compressor 24, and electrical loads such as the DT cooling water pump 28 and the cooling water pump 26. Is provided.

  An intake gas temperature sensor 201 for detecting the intake air temperature Ts is provided in the oxidant gas introduction flow channel 56 for introducing air that is outside air into the air compressor 24.

  The motor 18 is provided with a motor temperature sensor 202 that monitors the motor temperature Tm.

  The cooling water flow path 32 is provided with a DT water temperature sensor 203 that detects the DT water temperature Tr.

  The battery 16 is provided with a battery temperature sensor 204 that detects the battery temperature Tb.

  An FC water temperature sensor 205 that detects the FC water temperature Tw is provided in the cooling water flow path 36 of the fuel cell 14.

  The fuel gas circulation channel 48 of the fuel cell 14 is provided with an anode temperature sensor 206 that detects the fuel gas temperature Ta of the fuel cell 14, and a cathode outlet temperature sensor that detects the oxidant gas temperature Tc of the fuel cell 14. 207 is provided in the oxidant gas discharge channel 52.

  Further, an air conditioner temperature sensor 208 is provided for detecting the temperature of the vehicle speed wind 39 as an air conditioner temperature Tv for controlling the air conditioner 22.

  Motor temperature Tm monitored by the motor temperature sensor 202, DT system water temperature Tr detected by the DT system water temperature sensor 203, battery temperature Tb detected by the battery temperature sensor 204, FC system water temperature detected by the FC system water temperature sensor 205 Tw, fuel gas temperature Ta detected by the anode temperature sensor 206, oxidant gas temperature Tc detected by the cathode outlet temperature sensor 207, and air conditioner temperature Tv detected by the air conditioner temperature sensor 208 are controlled by the control unit 100. Detected.

  Although the fuel cell vehicle 12 in FIG. 1 does not have a dedicated high-accuracy temperature sensor for detecting the outside air temperature, the present invention can be implemented even if a dedicated high-accuracy temperature sensor for detecting the outside air temperature is provided. Can do.

  The control unit 100 outputs an activation signal for starting the fuel cell vehicle 12 (fuel cell 14), and also outputs an ignition switch (IGSW) 60 (activation) for outputting a stop signal for stopping the fuel cell vehicle 12 (fuel cell 14). Switch) is connected.

  The control unit 100 controls the overall operation of the fuel cell vehicle 12, including opening and closing various valves of the fuel cell vehicle 12, control of the DT system device 30, charge / discharge control of the battery 16, and the like.

  The control unit 100 is configured by a computer (ECU: Electronic Control Unit) including a CPU, a memory (ROM, RAM), a timer, an A / D converter, a D / A converter, and the like, and is stored in the memory based on various inputs. It operates as a functional means (functional unit) that realizes various functions by executing a program.

  In this embodiment, the control unit 100 functions as a startup required power increase unit 110, a stop charge amount determination unit 112, a winter season determination unit 114, a winter season determination prohibition / cancellation unit 116, and the like, as well as a scavenging control unit, an RTC ( It functions as a real time clock (CC) control unit, a remaining battery level (charge amount or SOC: State Of Charge) monitoring unit, a SOC threshold change unit (SOC threshold change unit), and the like.

  In practice, the SOC is detected by a battery control unit (not shown) incorporated in the battery 16 with reference to the input / output current, output voltage, temperature, and the like of the battery 16 and notified to the control unit 100. Although the control line is not shown, the control unit 100, as will be described later, passes the VCU 20 passing current {regenerative current from the motor 18, power generation current from the fuel cell 14, battery current from the battery 16 to the motor 18. (Drive current)} is sent to the VCU 20. The control unit 100 also functions as an energy management control unit for the entire fuel cell vehicle 12, including energy management for the battery 16.

  The operation of the fuel cell vehicle 12 basically configured as described above will be described next.

  The fuel cell vehicle 12 includes an intake air temperature sensor 201 and a motor temperature, which are the temperature sensors having the best followability with respect to the outside air temperature Tea, among the in-vehicle temperature sensors 201 to 208 during the soak when the fuel cell vehicle 12 is stopped. The intake air temperature Ts, the motor temperature Tm, and the DT system water temperature Tr, which are detected temperatures Tx of the sensor 202 and the DT system water temperature sensor 203, are monitored, and from the detected temperature Tx (Tx = Ts, Tm, or Tr) in winter (for example, 0 [° C] is a season in which there is a high possibility that the outside air temperature is likely to be below), and when it is determined that it is winter, the charge amount of the battery 16 is increased during operation of the fuel cell vehicle 12, and the SOC is regularly used. It is configured to shift the area higher.

  The temperature sensors 201 to 208 are sensors provided in the vehicle to control the electric load during driving, and all are highly accurate (fourth creation).

  Therefore, before the details of the operation are described, first, the external air temperature followability of the in-vehicle temperature sensors 201 to 208 is examined (experiment / confirmation), and the examination results will be described with reference to FIG.

  Secondly, the determination of the SOC and required power for starting the vehicle by the stop-time charge determination unit 112 when the winter determination unit 114 determines the winter season will be described with reference to FIGS. 3, 4, and 5. .

  First, the examination result about the temperature sensor with favorable outside air temperature followability will be described.

  FIG. 2 shows the fuel cell vehicle 12 (fuel cell) for three days and a half from the time point t1 to the time point t8 and from the time point t11 to the time point t16 (time points t9 and t10 are not drawn) under the outside air temperature Tea indicated by a one-dot chain line. 14 shows changes in the detected temperatures of the in-vehicle temperature sensors 201 to 208 when the operation state 14) is appropriately started and stopped.

  It can be seen from FIG. 2 that the temperature sensors 201 to 208 are basically classified into three groups.

  In the first group, the temperature hardly rises following the outside air temperature Tea, and the temperature rises immediately upon start-up (t1, t3, t5, t11, t13, t15), but at the time of soak (time t6 to t11, time Fuel gas that outputs a detected temperature Tpp exhibiting (power plant) internal temperature (P / P internal temperature) characteristics (temperature characteristics in which the follow-up temperature at the time of soak is not good) of the fuel cell 14 that is difficult to cool after t16) The temperature sensor group includes an anode temperature sensor 206 that detects the temperature Ta and a cathode outlet temperature sensor 207 that detects the oxidant gas temperature Tc.

  The second group outputs a detected temperature Ty that exhibits a temperature characteristic with good followability with respect to the outside air temperature Tea at the time of soaking (following the outside air temperature Tea after time t8 and after time t18). This is a temperature sensor group including a battery temperature sensor 204 to detect and an FC water temperature sensor 205 to detect an FC water temperature Tw.

  In the third group, when the fuel cell vehicle 12 (fuel cell 14) is started, the temperature rises immediately in response to the start, and the followability with respect to the outside air temperature Tea is the highest at the time of soak (time t6 to t11, time t16 to). An intake air temperature sensor 201 for detecting the intake air temperature Ts and a motor temperature sensor for detecting the motor temperature Tm, which output a detection temperature Tx exhibiting a good temperature characteristic (following the outside air temperature Tea after time t7 and after time t17). 202 is a temperature sensor group including 202 and a DT water temperature sensor 203 that detects a DT water temperature Tr.

  Based on the measurement results of FIG. 2, a temperature sensor (a temperature sensor with good external temperature tracking) that accurately determines whether or not it is the winter season during the soak when the fuel cell vehicle 12 is stopped is the outside air temperature during the soak. An intake air temperature sensor 201 for detecting an intake air temperature Ts belonging to a third group that outputs a detected temperature Tx exhibiting a temperature characteristic with the best followability with respect to Tea; a motor temperature sensor 202 for detecting a motor temperature Tm; It can be seen that the DT water temperature sensor 203 detects the DT water temperature Tr (fifth creation, sixth creation).

  The above is description of the examination result about the temperature sensor with favorable external temperature followability.

  Next, the required power for starting the vehicle by the startup required power increasing unit 110 when the winter determining unit 114 determines that it is winter will be described with reference to FIGS. 3, 4, and 5.

  FIG. 3 shows a general concept of changing the SOC threshold by the stop-time charge amount determination unit 112 when the winter determination unit 114 determines the winter season. When the winter season determination unit 114 determines the winter season, the stop-time charge amount determination unit 112 switches the SOC from the SOC during the summer (including spring and autumn other than the winter) to a higher value during the winter season.

  Specifically, the SOC threshold value for prohibiting idle stop is changed from the threshold value SOC1 to a larger threshold value SOC3. Similarly, the target SOC (or threshold value of the charge amount at the time of stoppage) is changed from SOC2 to SOC4.

  When the winter determination unit 114 determines that the winter season, the startup required power increase unit 110 increases the charge amount of the battery 16 during the operation of the fuel cell vehicle 12 (fuel cell 14) so as to be the SOC3 and SOC4. To do. In this case, the control unit 100 monitors the voltage and charge / discharge amount of the battery 16 so that the output current of the fuel cell 14 during operation of the fuel cell vehicle 12 (fuel cell 14) for charging the battery 16 increases. To control.

  If the increase in the amount of charge during operation is insufficient, the SOC of the battery 16 is detected when the ignition switch 60 is turned off, and the fuel cell 14 is generated until the detected SOC becomes SOC4, and then stopped. Let

  FIG. 4 shows a general concept of changing the SOC threshold value for prohibiting discharge by the stop-time charge amount determination unit 112 when the winter determination unit 114 determines the winter season. The vertical axis represents the battery upper limit output [kW]. When the winter season determination unit 114 determines that it is winter season, the charge amount determination unit 112 at the time of stopping changes the SOC threshold value for prohibiting discharge from the threshold value SOC5 to a larger threshold value SOC6. That is, control is performed so that the battery upper limit output [kW] can be output with a larger threshold SOC6 or more.

  The startup required power increase unit 110 increases the amount of charge of the battery 16 during operation of the fuel cell 14 and / or when the fuel cell 14 is stopped, as described above, so that the large threshold SOC6 is obtained.

  3 and 4, use prohibition areas are provided on the lower limit side of SOC (from SOC 0 [%] to a predetermined value [%]) and the upper limit side (from predetermined value [%] to SOC 100 [%]). This is to prevent deterioration of the battery 16.

  In FIG. 3, winter determination is performed by the winter determination unit 114, and the charge amount determination unit 112 during stop determines the target SOC, that is, the SOC that is the charge amount of the battery 16 when the vehicle is stopped (when the ignition switch 60 is off). When the SOC2 is increased from the SOC2 to the SOC4, the stop-time charge amount determination unit 112 preferably sets the battery charge amount upper limit value to a normal (spring, summer, autumn) charge amount upper limit value (referred to as summer charge amount upper limit value) SOCs. (For example, 65 [%]) is simultaneously increased to a winter charge amount upper limit SOCw (for example, 70 [%]) having a higher charge amount (eighth creation). Even when the SOC is increased to the winter charge amount upper limit SOCw when the winter season is determined, the battery temperature Tbat is lowered in the winter season, so that the deterioration of the battery 16 is not promoted. As a result, drivability during winter driving can be increased.

  In general, the battery 16, such as a lithium ion battery, deteriorates when left at a high temperature, for example, 40 [° C] or higher and a high SOC, for example, 70 [%] or higher. It is known that the reduction of the rated capacity is promoted. Specific values of the high temperature and high SOC that cause deterioration of the battery 16 can be individually determined in advance for each battery used or each type of battery used.

  FIG. 5 shows a general concept of the required power output [kW] (hereinafter also simply referred to as required output) to the fuel cell 14 by the stop-time charge amount determination unit 112 when the winter season determination unit 114 determines the winter season. ing.

  When the winter determination unit 114 determines that it is winter, the stop-time charge amount determination unit 112 replaces the power request output P1 for the fuel cell 14 when the vehicle stops in summer with the power request output P2 for winter, The power request output P2 for the fuel cell 14 is changed to the power request output P4 in winter.

  The startup required power increasing unit 110 increases the amount of charge of the battery 16 as described above so that the large required outputs P2 and P4 are obtained.

  The above description is about the SOC and required power for starting the vehicle by the stop-time charge amount determination unit 112 when the winter determination unit 114 determines the winter season.

  Next, details of the operation of the fuel cell vehicle 12 relating to the winter season determination will be described with reference to the flowchart of FIG. 6 and the time chart of FIG. In the time chart of FIG. 7, the operating state and the temperature transition are shown again in FIG. 2 for convenience of understanding.

  In step S1, the control unit 100 monitors whether or not the ignition switch 60 is turned on. When it is determined that the ignition switch 60 is turned on, in step S2, the winter season determination unit 114 sets the winter season determination flag Fw (Fw = 1). Represents winter season).

  When the winter season determination flag Fw is not set in step S2 (Fw = 0), in step S3, the winter season determination unit 114 determines that the intake air temperature sensor is a temperature sensor exhibiting the best temperature characteristics at the time of soak outside air temperature tracking. 201, motor temperature sensor 202, and DT system water temperature sensor 203 detect the intake air temperature Ts, motor temperature Tm, and DT system water temperature Tr, respectively, and detect any of the detected intake air temperature Ts, motor temperature Tm, and DT system water temperature Tr. It is determined whether or not the temperature Tx is 0 [° C.] or less (Tx ≦ 0 [° C.]).

  In consideration of the detection margin and sensor error, it is actually determined whether or not the temperature is equal to or lower than the temperature (Tx ≦ 0 + α [° C.]) which is + α [° C.] to 0 [° C.].

  If any temperature exceeds 0 [° C.], it is not determined as winter, in other words, it is determined as summer other than winter (including spring and autumn, also referred to as normal season in comparison with winter). The stop-time charge amount determination unit 112 determines the SOC and the required output described above in the summer state shown in FIGS.

  In step S <b> 4, the startup required power increasing unit 110 operates the fuel cell 14 with normal control so as to obtain the SOC and the required output, and charges the battery 16.

  If the intake air temperature Ts, the motor temperature Tm, or the DT water temperature Tr is 0 [° C.] or less in the determination in step S3 (step S3: YES), the winter season determination unit 114 is determined in step S5. Determines the winter season and sets the winter season determination flag Fw (Fw ← 1). The processing in step S5 corresponds to the behavior at time t1 shown in FIG.

  In this case, in step S5, the stop-time charge amount determination unit 112 determines the SOC and the required output from the summer state to the winter state as described with reference to FIGS.

  Next, in step S6, the startup required power increasing unit 110 switches the system of the fuel cell 14 to winter control so as to ensure the above S0C and required output.

  In step S7, the control unit 100 determines whether or not the ignition switch 60 is turned off.

  If the ignition switch 60 is on, the process of step S2: NO → S3: NO → S4 or step S2: YES → S6 is repeated. In this case, if the winter determination of step S3 is satisfied even once, since the winter determination flag Fw is set in step S5 (Fw ← 1), thereafter, step S2 is always satisfied, and the determination process of step S3 is performed. The operation is bypassed and the operation is switched to the winter control in step S6.

  In step S7, when it is detected that the ignition switch 60 is turned off, the control unit 100 backs up the winter season determination result (winter season determination flag Fw) in the memory in step S8.

  Next, during the soak of step S9 (mainly, after time t6 in FIG. 7 or after time t16), in step S10, the control unit 100 determines whether the soak time after starting and stopping has exceeded the predetermined time Tth. Determine if.

  This predetermined time Tth includes the intake air temperature sensor 201, the motor temperature sensor 202, and the DT system water temperature sensor 203, which are temperature sensors exhibiting the best temperature characteristics at the time of soak outside air temperature tracking, the motor temperature Tm, and the DT. Since it is known that the detected temperature Tx of the system water temperature Tw follows the outside air temperature Tea in about 4 hours (time t6 to t7 or time t16 to t17) after the operation stop time t6 (t16), the predetermined time Tth is Tth = 5 [h: time], which is slightly longer than this time, is set.

  In step S10, at the time points trtc1 and trtc2 at which the predetermined time Tth has elapsed, the winter season determination unit 114 in step S11, the intake air temperature sensor 201, which is a temperature sensor that exhibits the best temperature characteristics at the time of soak outside air temperature tracking, the motor temperature It is determined whether the detected temperature Tx of the intake air temperature Ts, the motor temperature Tm, or the DT water temperature Tr detected by the sensor 202 and the DT water temperature sensor 203 is lower than 0 [° C.] (Tx ≦ 0 [° C.]).

  If it is determined in step S11 that the temperature is equal to or lower than 0 [° C.] (see time point trtc1), the winter season is determined in step S12, and the winter season determination flag Fw is set (Fw ← 1). As in the example shown in the time chart of FIG. 7, when the winter season determination flag Fw has already been set, the winter season determination is continued.

  If it is determined in step S11 that the temperature is higher than 0 [° C], for example, at time trtc2 in the example shown in the time chart of FIG. The flag Fw is reset (Fw ← 0). That is, the winter season determination prohibition / cancellation unit 116 cancels the winter season determination.

  In step S14, the control unit 100 backs up the determination result in the memory.

  If it is determined in step S12 that the winter season is once determined, the confirmation of the winter season determination flag Fw in step S2 is always established at the time when the ignition switch 60 is turned on next time (step S1: YES). In S6, since the SOC and the required output are switched to the winter control while the fuel cell 14 is in operation, the battery 16 can be charged with a necessary charge amount.

  As a result, after a predetermined time after the operation stop in winter, for example, after 5 hours (in FIG. 7, time trtc1 and time trtc2), the air compressor 24 is operated by the electric power of the battery 16 whose amount of charge has been increased. By allowing dry compressed air to flow through the fuel gas flow path and the oxidant gas flow path of the battery 14, so-called scavenging treatment is performed, moisture in the fuel cell 14 is discharged, and freezing prevention and startup performance of the fuel cell 14 are improved. be able to.

  As described above, the fuel cell vehicle 12 according to the above-described embodiment stores the fuel cell 14 that generates power by the reaction of hydrogen gas and oxidant gas, stores the generated power from the fuel cell 14, and regenerative power from the motor 18. Battery 16 as a power storage device for storing the electric power, temperature sensors 201 to 203 mounted on the vehicle, necessary power for starting the vehicle {reactive gas (oxidant gas and hydrogen) flow path in the fuel cell 14 at the time of stoppage The scavenging power for draining water by the air compressor 24, the scavenging power for a predetermined time after elapse of a predetermined time after soaking, the starting power at the next startup, and the like. } At the time of start-up to increase the required power at the time of starting 110, and the amount of charge at the time of stopping to determine the SOC that is the amount of charge of the battery 16 when the vehicle is stopped (when the ignition switch 60 is off) so as to ensure the required power And a determination unit 112.

  The fuel cell vehicle 12 further determines whether or not the temperature Tx detected by the temperature sensors 201 to 203 is equal to or lower than 0 [° C.] which is a predetermined temperature after the vehicle stops, and determines that the winter season when the temperature is equal to or lower than the predetermined temperature. The determination by the winter determination unit 114 and the determination by the winter determination unit 114 is prohibited until the temperature Tx detected by the temperature sensors 201 to 203 is estimated to follow the outside air temperature Tea after the vehicle stops (for example, 5 [h]). And a winter determination prohibiting / releasing unit 116 that cancels the prohibition of the determination by the winter determining unit 114 when it is estimated to follow the outside air temperature Tea (first creation).

  According to this embodiment, as in the prior art, the outside air temperature Tea is not predicted, and the specific temperature sensor (intake air temperature sensor 201, motor temperature sensor 202 or DT) that easily follows the outside air temperature Tea is used. Since it is obtained by the actual measurement value (detected temperature Tx) of the system water temperature sensor 203) (because it is identified), the amount of charge that secures the SOC and the required output of the battery 16 at the time of stopping without predicting the outside air temperature The outside air temperature Tea for determining the temperature can be detected with high accuracy, and accurate winter season determination can be performed.

  In this case, since the outside air temperature prediction using communication means using radio waves such as GPS is not used, it is accurately stopped even in an environment where the temperature is different from the weather information, such as in a garage or underground parking lot. The amount of charge of the battery 16 at the time can be determined.

  By controlling as described above, in this embodiment of FIG. 8B compared to the prior art of FIG. 8A, the frequency of the SOC in a single operation of the fuel cell vehicle 12 is higher in winter than in summer. Is higher. That is, the charge amount of the battery 16 increases.

  Note that the intake air temperature sensor 201, the motor temperature sensor 202, or the DT water temperature sensor 203, which are these temperature sensors, are used to control the air compressor 24, the motor 18, or the air conditioner 22 that are electric loads in the vehicle, respectively. The temperature sensor is capable of following the outside air temperature Tea at the time of soaking after the vehicle stops.

  And in embodiment mentioned above, although these temperature sensors 201-203 are combined as a temperature sensor which detects outside temperature Tea, this invention is not restricted to this, The temperature sensor which detects outside temperature Tea exclusively It can also be implemented using. The dedicated outside air temperature sensor is easy to follow the outside air temperature, for example, is mounted and arranged under the front hood (bonnet) of the vehicle.

  Note that after the winter season determination unit 114 determines that the winter season is once (steps S5 and S12), the determination result is canceled because the winter season determination prohibition / cancellation unit 116 stops the vehicle (step S7) and the temperature sensor 201. Detected by the temperature sensors 201 to 203 while the vehicle is running (running) by assuming that the detected temperature Tx by ˜203 is from the time when it is estimated that the detected temperature Tx follows the outside air temperature Tea to the time of restart (second creation). It is possible to prevent the winter determination from being canceled as the temperature Tx increases.

  Specifically, the determination of the winter season is canceled by the winter season determination unit 114 when the detected temperature Tx is estimated to follow the outside air temperature Tea (time trtc1, trtc2) and after the restart (time t11, etc.). Then, it is determined whether or not the detected temperature Tx by the temperature sensors 201 to 203 is equal to or lower than 0 [° C.] which is a predetermined temperature. When the detected temperature Tx is equal to or higher than 0 [° C.], the determination result determined as the winter season is canceled (No. 1). 3 creation).

  Further, the condition that the winter determination prohibition / cancellation unit 116 estimates that the temperature Tx detected by the temperature sensors 201 to 203 follows the outside air temperature Tea after the vehicle stops is that a predetermined soak time, for example, 5 [h] has elapsed since the vehicle stopped. When the temperature is detected by the temperature sensors 201 to 203 every certain time, for example, every 0.5 [h], the amount of temperature change between the previous detection and the current detection [currently detected temperature Txc and 0.5 [h] When the value {(Txb−Txc) /0.5} obtained by dividing the difference from the previous (previous) detected temperature Txb by the elapsed time 0.5 [h] is smaller than a predetermined value, or the temperature at the previous detection In addition, when the temperature at the time of detection this time is higher, it is estimated that the detected temperature Tx by the temperature sensors 201 to 203 follows the outside air temperature Tea (seventh creation).

  As described above, the intake air temperature sensor 201, the motor temperature sensor 202, and the DT water temperature sensor 203 are used as temperature sensors for winter determination. Since these temperature sensors have good followability to the outside air temperature Tea (because they are fast), they can make a winter season determination immediately after the stop (sixth creation).

  If any one of the plurality of temperature sensors falls below a predetermined temperature, for example, 0 [° C] or less, the winter determination unit 114 performs the winter determination earlier if it is determined that it is winter. Can do. If it is determined that the winter season occurs when any two of the temperatures become 0 [° C.] or lower, the winter season determination can be performed more reliably.

  As described above, according to the above-described embodiment, the temperature sensor provided in the vehicle is used to control the electric load during driving (fourth creation). It is possible to determine whether or not it is necessary to increase the amount of charge), and to determine the amount of charge that ensures the SOC and the required output of the battery 16 when stopped.

  Note that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted based on the contents described in this specification.

  For example, a fuel cell vehicle 12A according to another embodiment as shown in FIG. 9 is configured to include a periodic activation unit 118 in the control unit 100A. The periodic activation unit 118 is activated every predetermined time, for example, every 5 minutes from the time when the ignition switch 60 is turned off, for example every 5 minutes, and at every 5 minutes, the detected temperature Tx by the temperature sensors 201 to 203 performs the scavenging process. It is determined whether or not the temperature is close to the required freezing temperature, for example, a temperature lower than a threshold temperature of 5 [° C.].

  When the temperature is lower than the threshold temperature 5 [° C.], it is estimated that the oxidant gas channel in the fuel cell 14 and the droplet (water) remaining in the fuel gas channel may freeze. In order to discharge the droplets (water) from the fuel cell 14, the control unit 100A drives the air compressor 24 for a predetermined time, supplies compressed air from the air compressor 24 to the oxidant flow path, and fuel gas. A so-called scavenging process is performed in which water is supplied to the flow path and the moisture is discharged from the oxidant gas flow path and the fuel gas flow path by the compressed air.

  The linkage operation with the winter season determination process of the fuel cell vehicle 12A performing such a scavenging process will be further described with reference to the time chart of FIG. In this linkage operation, the regular activation unit 118 is also used as a timer for winter determination processing.

  After the ignition switch 60 is turned off and stopped at the time t21, until the time t22 when the temperature Tx detected by the temperature sensors 201 to 203 is estimated to follow the outside air temperature Tea, the winter determination process and the winter season are performed by the winter determination unit 114. Execution of processing by the determination prohibition / cancellation unit 116 (both processes are collectively referred to as winter determination processing, etc.) is prohibited.

  In addition, after the time point t22, during the period in which the detected temperature Tx is estimated to follow the outside air temperature Tea, until the time point t23 at which the scavenging process is started, the periodic activation unit 118 performs the winter season determination unit 114 or the predetermined time interval. The winter season determination prohibition / cancellation unit 116 is activated to execute winter season determination processing and the like.

  Further, the regular activation unit 118 is periodically activated from time t21 to time t23. Since it is determined that the temperature has fallen below the threshold temperature 5 [° C.] at the time of regular startup at time t23, the scavenging process is performed between time t23 and t24. During this time, the temperature detected by the temperature sensors 201 to 203 is performed. Since Tx increases, the winter season determination process is prohibited until time t25 when it is estimated that the detected temperature Tx follows the outside air temperature Tea.

  After the time point t25, the periodic activation unit 118 again periodically activates the winter determination unit 114 or the winter determination prohibition / cancellation unit 116 to execute winter determination processing and the like. At time t26, the ignition switch 60 is turned on.

  Since the scavenging process is executed between the time points t23 and t25, the periodic activation unit 118 is not periodically activated between the time points t23 and t25.

  The temperature sensor that measures the temperature every 5 minutes after the start and stop may be the same as or different from the temperature sensors 201 to 203 for winter determination.

  Further, when the temperature monitoring every 5 minutes triggered by the activation of the periodic activation unit 118 is defined as RTC monitoring using the RTC control unit of the control unit 100A, between the time t21 and t23 and between the time t25 and t26. Then, although RTC monitoring is performed, it is not necessary to perform RTC monitoring between time t23 and t25 (non-execution).

  FIG. 11 shows a fuel cell vehicle 12B according to still another embodiment, and this fuel cell vehicle 12B is configured as a control unit 100B further including a regenerative limiting power management unit 120.

  FIG. 12 is a block diagram illustrating a detailed configuration example of the regeneration limited power management unit 120 illustrated in FIG. 11.

  In the fuel cell vehicle 12B in the example of FIG. 11, the vehicle is traveling in a state determined by the winter determination unit 114 as winter (for example, in FIG. 7, the winter is determined at time trtc1 and the winter determination flag Fw = 1). When the temperature detected by the battery temperature sensor 204 that detects the battery temperature Tb of the battery 16 rises above a predetermined temperature, for example, a high temperature such as 40 [° C.] during the period (for example, time t13 to t14), the winter determination unit A winter determination temporary counterfeit portion 126 that temporarily counteracts the winter determination by 114 is provided (9th creation).

  The reason will be described. The battery 16 is promoted to deteriorate in a high temperature state and a high SOC state. Even in the winter season, if the regenerative power from the motor 18 increases during traveling and the SOC increases with charging, there is a possibility that a high temperature state and a high SOC state in which deterioration is promoted may occur. Therefore, in order to satisfy the endurance guarantee of the battery 16 and to ensure the lifetime, the winter determination temporary reaction part 126 temporarily causes the winter season to be continued so that the high temperature state and the high SOC state are not continued. The determination is countered and the winter determination flag Fw is temporarily reset (Fw ← 0).

  Accordingly, in order to avoid the occurrence of a high temperature state and a high SOC state, it is necessary to return the winter charge amount upper limit SOCw (for example, 70 [%]) to the normal charge amount upper limit SOCs (for example, 65 [%]). (See FIG. 3).

  However, when pulling back, the following attention is required. That is, as shown in the regeneration limit power Prl [W] vs. SOC [%] map (characteristics) in FIG. 13, winter regeneration of the winter regeneration limit power map 124 having the winter charge amount upper limit SOCw indicated by a one-dot chain line. The limit power Prlw (SOC) is a value from 0 to the SOCn value compared to the normal regeneration limit power Prls (SOC) of the normal regeneration limit power map 122 having the normal charge amount upper limit SOCs indicated by a solid line. Up to the same regeneration limit power upper limit value Prlmax, regenerative power can be regenerated to the battery 16 as charging power, but when the SOC value becomes larger than the SOCn value, the value of normal regeneration limit power Prls (SOC) Is smaller than the value of the winter regenerative limiting power Prlw (SOC), which is a {Prls (SOC) <Prlw (SOC)} relationship.

  Therefore, when the winter season determination flag Fw is reset, immediately when the winter regeneration limit power SOCw is pulled back to the normal regeneration limit power SOCs, the actual SOC value when SOC is pulled back is between SOCs <SOC <SOCw. , The regenerative electric power from the motor 18 cannot be charged into the battery 16, and so-called regenerative loss (a situation where the braking force generated by the action of the motor 18 as a generator is not applied) occurs. appear.

  Therefore, in order to prevent this regeneration failure, when the battery temperature Tb rises above a predetermined temperature during traveling, the winter determination flag Fw is temporarily set by the winter determination temporary reaction unit 126 to temporarily counter the winter determination. (Fw ← 0) and ← 0), in order to avoid drastic impossibility of regenerative electric power Prl from the driving motor 18 for the fuel cell vehicle 12B in consideration of drivability. The regenerative limited power management unit 120 returns the winter charge amount upper limit value SOCw of the battery 16 to the normal charge amount upper limit value SOCs from the temporary charge amount upper limit value SOCm (see FIG. 13) gradually lowered by, for example, rate limit processing. And (further tenth creation).

  In this way, a plurality of temporary regenerative limiting power maps 123 indicated by dotted lines having the temporary charge amount upper limit SOCm in FIG. 13 are provisionally used, and the regenerative limiting power for winter that is the characteristic of the one-dot chain line in FIG. If the map 124 is gradually made asymptotically from the map 124 to the normal regeneration limit power map 122, which is a characteristic of the solid line, the temporary regeneration limit power Prlm (SOC) does not become a zero value, and regeneration is applied.

  In practice, the normal regenerative limit power map 122, the temporary regenerative limit power map 123, and the winter regenerative limit power map 124 have different maps (characteristics) with the battery temperature Tb as a parameter. To do.

  The operation of the regeneration limited power management unit 120 controlled as described above will be described more specifically with reference to FIG. This operation is limited to traveling, but when the winter determination flag Fw is set (Fw = 1) during traveling, the common contact c of the switch 128 is connected to the contact y, and the battery temperature When Tb is equal to or lower than the predetermined temperature Tbmax, Tbmax ≧ Tb is not established, so one input of the AND circuit 138 becomes 0 value, and the AND of the AND circuit 138 of the winter decision temporary reaction part 126 is not established. Thus, the common contact c of the switch 130 is connected to the contact n side, and the regenerative limit power Prl {= Prlw (SOC)} is calculated by referring to the winter regenerative limit power map 124 and notified to the VCU 20. The VCU 20 charges the battery 16 by limiting the regenerative power from the motor 18 to the regenerative limited power Prl {= Prlw (SOC)}.

  When the winter season determination flag Fw is reset (Fw = 0), the common contact c of the switch 128 is connected to the contact n side, and the logical product of the AND circuit 138 is always not established. The common contact c is also connected to the contact n side, and the regenerative limit power Prl {= Prls (SOC)} is calculated with reference to the normal regenerative limit power map 122.

On the other hand, when the winter season determination flag Fw is set during driving (Fw = 1), the common contact c of the switch 128 is connected to the contact y, and the AND circuit when the battery temperature Tb becomes equal to or higher than the predetermined temperature Tbmax. One input of 138 becomes 1 value, the logical product of the AND circuit 138 of the winter decision temporary counter part 126 is established, and the common contact c of the switch 130 is connected to the contact y side. At this time, one input of the comparison unit 134 is supplied with the winter regeneration limit power previous value Prlw ⁻¹ in which the winter regeneration limit power Prlw (SOC) is delayed by one sampling delay unit (Z ⁻¹ ) 139. However, since this value is much larger than the normal regenerative limiting power Prls, the comparison result {Prlw (SOS) −Prls (SOC)> ΔPrl: ΔPrl is a predetermined value for avoiding so-called regeneration omission. } Is established, and the common contact c of the switch 132 is connected to the contact y. As a result, the regenerative limiting power Prlw (SOC) for winter is gradually reduced (rate-limited) for each sampling process by the gradually decreasing unit 136.

  As described above, when the comparison result of the comparison unit 134 is finally established from the winter regenerative limit power map 124 related to the winter regenerative limit power Prlw (SOC) indicated by a one-dot chain line in FIG. Until the contact point c is switched to the contact point n side, the voltage gradually decreases in the temporary regeneration limit power map 123 related to the temporary regeneration limit power Prlm (SOC) indicated by the dotted line. When the common contact c of the switch 132 is switched to the contact n side, the switching to the normal regenerative limited power map 122 related to the normal regenerative limited power Prls (SOC) indicated by the solid line is completed.

  It should be noted that once the logical product of AND circuit 138 is established, it is preferable to provide hysteresis to predetermined temperature Tbmax so that chattering does not occur in switch 130.

1 is a schematic configuration diagram of a fuel cell vehicle according to an embodiment of the present invention. It is explanatory drawing of the detection temperature transition of a vehicle-mounted temperature sensor. It is explanatory drawing, such as target SOC of winter and summer. It is explanatory drawing of the battery upper limit output of a winter season and a summer season. It is explanatory drawing of the request | requirement output in winter and summer. It is a flowchart provided for operation | movement description of winter determination. It is a time chart used for operation | movement description of winter determination. FIG. 8A is a frequency distribution diagram of SOC in winter and summer according to the prior art, and FIG. 8B is a frequency distribution diagram of SOC in winter and summer according to this embodiment. It is a schematic block diagram of the fuel cell vehicle which concerns on other embodiment of this invention. 10 is a time chart used for explaining the operation of the example in FIG. 9. It is a schematic block diagram of the fuel cell vehicle which concerns on further another embodiment of this invention. It is a block diagram which shows the detailed structural example of a regeneration limitation electric power management part. It is explanatory drawing of a regeneration limiting electric power versus SOC map (characteristic).

Explanation of symbols

DESCRIPTION OF SYMBOLS 12, 12A, 12B ... Fuel cell vehicle 14 ... Fuel cell 16 ... Battery 18 ... Motor 100, 100A, 100B ... Control part 110 ... Required power increase part 112 at the time of starting 112 ... Charge determination part 114 at the time of stop ... Winter judgment part 116 ... Winter determination prohibition / cancellation unit 118 ... Periodic activation unit 120 ... Regenerative limit power management unit 126 ... Winter determination temporary counter part 201 ... Intake temperature sensor 202 ... Motor temperature sensor 203 ... DT system water temperature sensor 204 ... Battery temperature sensor 205 ... FC Water temperature sensor 206 ... Anode temperature sensor 207 ... Cathode outlet temperature sensor 208 ... Air temperature sensor

Claims (8)

A fuel cell that generates electricity by the reaction of hydrogen gas and oxidant gas;
A power storage device for storing power from the fuel cell;
A temperature sensor mounted on the vehicle;
A required power increase unit at start-up that increases the required power for vehicle start-up in winter,
A stop-time charge amount determining unit that determines a charge amount of the power storage device when the vehicle is stopped so as to secure the necessary power;
In a fuel cell vehicle comprising:
Determining whether or not the temperature detected by the temperature sensor is equal to or lower than a predetermined temperature after the vehicle stops, and determining the winter when the temperature is equal to or lower than the predetermined temperature;
Until it is estimated that the temperature detected by the temperature sensor follows the outside air temperature after the vehicle stops, the determination by the winter season determination unit is prohibited, and when it is estimated to follow the outside air temperature, the winter season determination unit The winter judgment prohibition / cancellation part that cancels the prohibition of discrimination,
A fuel cell vehicle comprising: The fuel cell vehicle according to claim 1, wherein
The winter determination unit once determines that the winter season and then cancels the determination result because the winter determination prohibition / cancellation unit detects that the temperature detected by the temperature sensor follows the outside air temperature after the vehicle stops. Then, the fuel cell vehicle is characterized in that it is between the time after estimation and the time of restart. The fuel cell vehicle according to claim 2, wherein
Between when the detected temperature is estimated to follow the outside air temperature and after the restart, the winter determination unit determines whether the temperature detected by the temperature sensor is equal to or lower than a predetermined temperature, and The fuel cell vehicle, wherein the determination result determined as the winter season is canceled when the temperature is equal to or higher than a temperature. The fuel cell vehicle according to any one of claims 1 to 3 ,
The winter judgment prohibition / cancellation part is
The condition for estimating that the temperature detected by the temperature sensor follows the outside air temperature after the vehicle stops is:
When a temperature is detected by the temperature sensor at regular intervals after a predetermined soak time has elapsed since the vehicle stopped,
When the temperature change amount in the certain time is smaller than a predetermined value, or when the detected temperature when the certain time has elapsed is higher than the detected temperature before the certain time, the detected temperature by the temperature sensor is A fuel cell vehicle characterized by being estimated to follow the outside air temperature. In the fuel cell vehicle according to any one of claims 1 to 4 ,
The stopping charge amount determining unit
When the winter season determination unit determines that the winter season, the fuel cell vehicle further sets the upper limit charge amount of the power storage device to a winter charge upper limit value higher than the normal charge amount upper limit value. The fuel cell vehicle according to claim 5 , wherein
When the temperature detected by the temperature sensor for detecting the temperature of the power storage device rises above a predetermined temperature during traveling in the state determined as winter by the winter determination unit, the determination of winter is temporarily countered. A fuel cell vehicle, further comprising a temporary decision part for winter determination. The fuel cell vehicle according to claim 6 , wherein
In order to prevent the regenerative power from the travel drive motor of the fuel cell vehicle from suddenly becoming unrecoverable when the winter determination is temporarily countered by the winter determination temporary counterfeit portion, A fuel cell vehicle, further comprising a regeneration limited power management unit that gradually returns the winter charge amount upper limit value of the power storage device to the normal charge amount upper limit value. The fuel cell vehicle according to any one of claims 1 to 7 ,
The temperature detected by the temperature sensor mounted on the vehicle is
A temperature detected by an intake air temperature sensor at an inlet of an air compressor that compresses outside air and supplies the fuel cell as the oxidant gas, a temperature detected by a motor temperature sensor that measures a temperature of a driving motor for the fuel cell vehicle, Or a temperature detected by a cooling water temperature sensor for measuring a temperature of cooling water of a radiator that cools the driving motor.

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