JP6819719B2 - Vehicle power supply - Google Patents

Description

The present invention relates to a vehicle power supply device for diagnosing an abnormality of a power supply mounted on a vehicle.

A hybrid electric vehicle (HEV) equipped with an engine and a motor, a plug-in hybrid electric vehicle (PHEV) having a rechargeable battery that can be charged by electric power from the outside of the vehicle, and an engine and a motor, and a fuel cell vehicle (PHEV) having a fuel cell. In the power supply device, harness, and other electrical components in the equipment mounted on the FCV), continuity abnormalities occur due to improper assembly or deterioration that occurs in the process of using the vehicle.

As an example of a vehicle power supply device that detects such a continuity abnormality, the one described in Patent Document 1 is known. In Patent Document 1, the power supply device for a vehicle is a traveling battery in which a plurality of batteries are connected in series, a forced discharge circuit that temporarily discharges the traveling battery, and a current in the discharged state of the forced discharge circuit. A current detection circuit to detect, a voltage detection circuit to detect the battery voltage in the discharged state of the forced discharge circuit, an impedance detection circuit to detect the series impedance from the detected voltage and the detected current, and a connection abnormality from the detected series impedance. It is provided with a determination circuit for determining. The forced discharge circuit is a series circuit of the discharge resistor and the discharge switch, and the discharge switch is turned on to discharge the traveling battery. The determination circuit compares the set impedance stored in the storage unit with the detected series impedance, and determines the connection abnormality in a state where the series impedance is larger than the set impedance. (See, for example, Patent Document 1)

Japanese Unexamined Patent Publication No. 2011-69720

However, in the above-described example of the vehicle power supply device, since it is necessary to switch to the forced discharge circuit when diagnosing a connection abnormality, it is not possible to switch to the forced discharge circuit at a timing such as during traveling. Therefore, the connection abnormality cannot be determined. Therefore, the number of diagnosis of connection abnormality cannot be sufficiently secured, and the diagnosis accuracy cannot be improved.

Therefore, the present invention provides a vehicle power supply device capable of diagnosing abnormalities of electric power system parts not only when the ignition switch is turned on but also while the vehicle is running in a vehicle having a plurality of power sources. The purpose.

The vehicle power supply device according to one aspect for solving the above problems is a vehicle power supply device having a first power source having a power generation function and a second power source having a power storage function, and is a first power source or a second power source. A determination unit that determines the power supply as a diagnosis target and a diagnosis unit that diagnoses an abnormality regarding continuity abnormality between the first power supply and the second power supply based on the result of the determination unit are provided, and the determination unit determines the second power supply as an abnormality. It has a first diagnosis mode in which the first power supply is abnormally diagnosed after diagnosis, and a second diagnosis mode in which the second power supply is abnormally diagnosed after the first power supply is abnormally diagnosed, and the determination unit charges the second power supply. When the capacity is less than the first threshold set so as not to fall below the lower limit of the controllable charge capacity of the second power supply, the first diagnostic mode is selected and the charge capacity of the second power supply is the first threshold value. In the above case, the second diagnosis mode is selected, and the diagnosis unit performs the abnormality diagnosis .

According to one aspect, by changing the diagnostic mode according to the charge capacity of the second power supply, the second power supply is supplied from the second power supply even if the required output from the driver is changed at the time of diagnosis of the first power supply. It is possible to prevent the output current from becoming insufficient. Therefore, it is possible to suitably perform the abnormality diagnosis even in the traveling state where the required output for the vehicle changes.

FIG. 1 is a schematic configuration diagram of a vehicle equipped with a vehicle power supply device according to an embodiment of the present invention. FIG. 2 is a block diagram of a vehicle controller according to an embodiment of the present invention. FIG. 3 is a flowchart illustrating the operation of the vehicle power supply device according to the embodiment of the present invention. FIG. 4 is a flowchart illustrating the operation of abnormality diagnosis in the power storage unit of the vehicle power supply device of FIG. Figure 5 is a timing chart illustrating the transition of the current I _N of the power storage power supply unit according to the abnormality diagnosis of the power storage power supply. FIG. 6 is a timing chart for explaining the transition of the required power output from the vehicle power supply device according to the abnormality diagnosis of the power storage power supply unit. Figure 7 is a timing chart illustrating the transition of the current I _M of the power supply unit according to the abnormality diagnosis of the power storage power supply. FIG. 8 is a flowchart illustrating the operation of abnormality diagnosis in the power generation power supply unit of the vehicle power supply device of FIG. Figure 9 is a timing chart illustrating the transition of the current I _M of the power supply unit according to the abnormality diagnosis of the power supply unit. FIG. 10 is a timing chart for explaining the transition of the required power output from the vehicle power supply device according to the abnormality diagnosis of the power generation power supply unit. Figure 11 is a timing chart illustrating the transition of the current I _N of the power storage power supply unit according to the abnormality diagnosis of the power supply unit.

The vehicle power supply device according to an embodiment of the present invention is a vehicle power supply device having a first power supply having a power generation function and a second power supply having a power storage function, and is a first power supply or a second power supply. The determination unit is provided with a determination unit for determining each of the items to be diagnosed, and a diagnosis unit for diagnosing an abnormality regarding continuity abnormality between the first power supply and the second power supply determined by the determination unit. It has a first diagnosis mode in which the first power supply is abnormally diagnosed after diagnosis, and a second diagnosis mode in which the second power supply is abnormally diagnosed after the first power supply is abnormally diagnosed, depending on the charge capacity of the second power supply. A vehicle power supply device can be provided in which the diagnosis unit performs an abnormality diagnosis by selecting the first diagnosis mode or the second diagnosis mode.

Hereinafter, a vehicle power supply device according to an embodiment of the present invention will be described with reference to the drawings. 1 to 11 are views for explaining a vehicle power supply device according to an embodiment of the present invention.

As shown in the schematic configuration diagram of FIG. 1, the vehicle 100 is an electric vehicle that travels by using the driving force of the motor M. The vehicle 100 includes a vehicle power supply device 1 that supplies electric power to the motor M, and an inverter 2 that converts the direct current generated by the vehicle power supply device 1 into an alternating current and then supplies electric power to the motor M. Consists of.

The vehicle power supply device 1 includes a power generation power supply unit PSU1 having a power generation function, a power storage power supply unit PSU2 having a power storage function, and a DC / DC converter unit DCU that converts a voltage output from the power generation power supply unit PSU1. It is composed.

The power generation power supply unit PSU1 is a fuel cell, and is configured as a fuel cell stack by combining a plurality of fuel cell FCs. The cooling method of the fuel cell may be either a water-cooled type or an air-cooled type, and the anode gas of the fuel cell may be either hydrogen or methane. Further, the power generation power supply unit PSU1 is not limited to the fuel cell, and may be a power generation power source that drives a generator by using the power of an internal combustion engine to generate power.

The power generation power supply unit PSU1 has a voltage sensor VS1 for at least one fuel ionization cell FC in FIG. As an example of FIG. 1, the voltage sensor VS1 is arranged in each fuel cell FC, but the voltage sensor VS1 may be arranged in a set of a plurality of fuel cell FCs. Further, the power generation power supply unit PSU1 has a voltage sensor VS2 that detects a voltage between the positive electrode and the negative electrode of the fuel cell stack. Further, the relay RL1 and the current sensor AS1 are connected to the positive electrode of the fuel cell stack. A relay RL2 is connected to the negative electrode to form a power generation power supply unit PSU1.

The power storage unit PSU2 is a storage battery capable of storing electric power or the like generated by the power generation power supply unit PSU1, and is configured by combining a plurality of battery cells BC. This storage battery can be a lithium ion secondary battery, a nickel hydrogen storage battery, or the like. However, any type of electrolyte in the storage battery of the present invention may be used.

The power storage unit PSU2 has at least one voltage sensor VS5 installed for each storage battery cell BC. Further, the relay RL3 and the current sensor AS4 are connected to the positive electrode of the storage battery. A service plug SP is connected to the negative electrode to form a power storage unit PSU2. In FIG. 1, the voltage sensor VS5 is arranged in each storage battery cell BC as an example, but the voltage sensor VS5 may be arranged in a set of a plurality of storage battery cells BC.

The DC / DC converter unit DCU includes a DC / DC converter DCC, a voltage sensor VS3 that detects the voltage difference between the positive voltage of the DC / DC converter DCC on the power generation power supply unit PSU1 side and the negative voltage of the DC / DC converter DCC, and a storage power supply. A voltage sensor VS4 that detects the voltage difference between the positive electrode of the DC / DC converter DCC on the unit PSU2 side and the negative voltage of the DC / DC converter DCC is connected. Further, in the DC / DC converter unit DCU, the current sensor AS2 is connected to the positive electrode side where the output from the power generation power supply unit PSU1 is input. Further, in the DC / DC converter unit DCU, the current sensor AS3 is connected to the positive electrode side for inputting the output from the storage power supply unit PSU2.

The terminal N1 of the power generation power supply unit PSU1 and the terminal N3 of the DC / DC converter unit DCU are connected, and the terminal N2 of the power generation power supply unit PSU1 and the terminal N4 of the DC / DC converter unit DCU are connected. The terminal N7 of the power storage unit PSU2 and the terminal N5 of the DC / DC converter unit DCU are connected, and the terminal N8 of the power storage unit PSU2 and the terminal N6 of the DC / DC converter unit DCU are connected.

The vehicle controller 3 (hereinafter, also referred to as VCU) provided in the vehicle 100 has a function of controlling the amount of power generated by the power generation power supply unit PSU1 and the amount of charge or discharge of the power storage unit PSU2. Further, the VCU 3 controls the output voltage and the output current with respect to the DC / DC converter unit DCU. Further, the VCU 3 controls the voltage and frequency output from the inverter 2.

As shown in the block diagram of FIG. 2, the vehicle controller 3 has a diagnosis unit 31, a determination unit 32, and a drive control unit 33.

The diagnosis unit 31 executes an abnormality diagnosis of the power generation power supply unit PSU1 or the storage power supply unit PSU2 based on the order determined by the determination unit 32. When executing the abnormality diagnosis of the power generation power supply unit PSU1, the diagnosis unit 31 calculates the internal resistance value for the fuel cell FC, the relays RL1 and RL2, and executes the abnormality diagnosis based on the internal resistance value. When executing the abnormality diagnosis of the power storage unit PSU2, the internal resistance value is calculated for the storage battery cell BC and the relay RL3 and the abnormality diagnosis is executed in the same manner as when the abnormality diagnosis of the power generation power supply unit PSU1 is executed.

The determination unit 32 has a first diagnosis mode in which the power storage unit PSU1 is abnormally diagnosed after the power storage unit PSU2 is abnormally diagnosed based on the charge capacity of the power storage unit PSU2, and a storage power supply after the power generation power supply unit PSU1 is abnormally diagnosed. Select the second diagnostic mode for abnormally diagnosing the unit PSU2.

The drive control unit 33 calculates a required output based on the amount of depression and operation of the accelerator pedal (not shown) of the driver boarding the vehicle 100, and outputs the power supply device 1 for the vehicle so as to satisfy the required output. And the rotation speed of the motor M are controlled.

The voltage output from the five voltage sensors VS1, VS2, VS3, VS4, and VS5 is input to the input port of the vehicle controller 3. Further, the currents output from the four current sensors AS1, AS2, AS3, and AS4 are input to the input port of the vehicle controller 3. Further, the outputs of various sensors such as the stroke of the accelerator pedal (not shown) and the stroke of the brake pedal (not shown) are input.

A request output to the power generation power supply unit PSU1 and a request output to the DC / DC converter unit DCU are output from the output port of the vehicle controller 3. Further, a display unit 34 and a voice output unit 35 for notifying the driver of vehicle information are connected to the output port of the vehicle controller 3.

That is, in the vehicle power supply device 1, the drive control unit 33 of the vehicle controller 3 calculates the required output based on the operation amount input from the accelerator pedal or the brake pedal (not shown). Further, the drive control unit 33 determines the outputs of the power generation power supply unit PSU1 and the storage power supply unit PSU2 so as to satisfy the required output of the motor M, and controls the power generation power supply unit PSU1 and the storage power supply unit PSU2.

(Selection of diagnostic mode)
Next, in the vehicle power supply device 1 according to the present embodiment, the abnormality diagnosis executed by the vehicle controller 3 will be described with reference to the flowchart of FIG.

In step S1, the determination unit 32 determines whether the charge capacity SOC of the power storage unit PSU2 is less than the first threshold value. Here, when the charge capacity SOC of the power storage unit PSU2 is less than the first threshold value (YES), the first diagnosis mode for abnormally diagnosing the power generation power supply unit PSU1 after abnormally diagnosing the power storage unit PSU2 is selected (step). S11). When the charge capacity SOC of the power storage unit PSU2 is equal to or higher than the first threshold value (NO), a second diagnosis mode for abnormally diagnosing the power storage unit PSU2 after abnormally diagnosing the power generation power supply unit PSU1 is selected (step S21). ..

In step S1, when the charge capacity SOC of the power storage unit PSU 2 is less than the first threshold value (YES), the determination unit 32 proceeds to step S11, and based on the determination of the determination unit 32 in step S1, the first diagnostic mode. Select.

In step S12, the diagnosis unit 31 executes the abnormality diagnosis of the power storage unit PSU2 based on the selection of the first diagnosis mode in step S11. Here, the abnormality diagnosis of the power storage unit PSU2 of the vehicle power supply device 1 is executed based on the flowchart of FIG. Details of the abnormality diagnosis of the power storage unit PSU2 will be described later.

In step S13, it is determined whether or not the abnormality diagnosis of the power storage unit PSU2 executed in step S12 is completed. If the abnormality diagnosis is not completed (NO), step S13 is repeated. If the abnormality diagnosis is completed (YES), the process proceeds to step S14.

If it is determined in step S13 that the abnormality diagnosis of the power storage unit PSU2 has been completed, steps S14 and S16 are performed based on the charge capacity SOC of the power storage unit PSU2 at the end of the abnormality diagnosis of the power storage unit PSU2. Make a judgment.

In step S14, it is determined whether the charge capacity SOC of the power storage unit PSU2 is equal to or greater than the first threshold value. If the charge capacity SOC of the power storage unit PSU2 is less than the first threshold value (NO), the process proceeds to step S15. If the charge capacity SOC of the power storage unit PSU2 is equal to or greater than the first threshold value (YES), the process proceeds to step S16.

In step S15, in step S14, when the charge capacity SOC of the power storage unit PSU2 is less than the first threshold value (NO), the drive control unit 33 corrects the output current from the power generation power supply unit PSU1 to increase. That is, in order to increase the charge capacity SOC of the power storage unit PSU2, the output ratio of the power generation power supply unit PSU1 to the required output is increased.

In step S16, it is determined whether the charge capacity SOC of the power storage unit PSU2 is larger than the second threshold value. If the charge capacity SOC of the power storage unit PSU2 is larger than the second threshold value (NO), the process proceeds to step S17. If the charge capacity SOC of the power storage unit PSU2 is equal to or less than the second threshold value (YES), the process proceeds to step S18.

In step S17, in step S16, when the charge capacity SOC of the power storage unit PSU2 is larger than the second threshold value (NO), the drive control unit 33 corrects the output current from the power generation power supply unit PSU1 to decrease. That is, in order to reduce the charge capacity SOC of the power storage unit PSU2, the output ratio of the power generation power supply unit PSU1 to the required output is reduced.

When step S15 or step S17 is completed, the process returns to step S14, the determinations of steps S14 and S16 are repeated, and steps S15 and S17 for adjusting the charge capacity SOC of the power storage unit PSU2 are executed.

If the charge capacity SOC of the power storage unit PSU2 is not within an appropriate range at the time of abnormality diagnosis of the power generation power supply unit PSU1, the power storage power supply unit PSU2 may be overcharged or overdischarged. That is, during the abnormality diagnosis in which the output current of the power generation power supply unit PSU1 is limited, the required output to the vehicle power supply device 1 is greatly increased, so that the power taken out from the power storage power supply unit PSU2 is increased, so that the power storage power supply unit PSU2 Is over-discharged. Further, during the abnormality diagnosis in which the output current of the power generation power supply unit PSU1 is limited, the required output to the vehicle power supply device 1 is greatly reduced, so that the amount of charge to the power storage power supply unit PSU2 is increased, so that the power storage power supply unit is increased. PSU2 is overcharged. In order to prevent such overcharging or overdischarging, steps S15 and S17 are carried out so that the charge capacity SOC of the power storage unit PSU2 from the power generation power supply unit PSU1 becomes a suitable state. Therefore, it is possible to preferably prevent the power storage unit PSU2 from being overcharged or overdischarged.

In step S18, when the charge capacity SOC of the power storage unit PSU2 is in the range of the predetermined first threshold value or more and the second threshold value or less in steps S14 and S16, the diagnostic unit 31 diagnoses the abnormality of the power generation power supply unit PSU1. To execute. Here, the abnormality diagnosis of the power generation power supply unit PSU1 of the vehicle power supply device 1 is executed based on the flowchart of FIG. Details of the abnormality diagnosis of the power generation power supply unit PSU1 will be described later.

In step S19, it is determined whether or not the abnormality diagnosis of the power generation power supply unit PSU1 executed in step S18 has been completed. If the abnormality diagnosis is not completed (NO), step S19 is repeated. When the abnormality diagnosis of the power generation power supply unit PSU1 is completed (YES), the first diagnosis mode is terminated.

Next, the second diagnostic mode will be described. In step S1, when the charge capacity SOC of the power storage unit PSU1 is larger than the first threshold value, in step S21, the determination unit 32 selects the second diagnostic mode based on the determination in step S1.

In step S22, it is determined whether the charge capacity SOC of the power storage unit PSU2 is less than the third threshold value. When the charge capacity SOC of the power storage unit PSU2 is less than the third threshold value (YES), the process proceeds to step S24, and the abnormality diagnosis of the power generation power supply unit PSU1 is executed. When the charge capacity SOC of the power storage unit PSU2 is equal to or higher than the third threshold value (NO), the process proceeds to step S23.

In step S23, in step S22, when the charge capacity SOC of the power storage unit PSU2 is equal to or greater than the third threshold value (NO), the output current of the power generation power supply unit PSU1 is corrected to decrease. That is, in order to reduce the charge capacity SOC of the power storage unit PSU2, the output ratio of the power generation power supply unit PSU1 to the required output is reduced. Steps S22 and S23 are repeated until the charge capacity SOC of the power storage unit PSU2 becomes less than the third threshold value.

If the charge capacity SOC of the power storage unit PSU2 is not within an appropriate range when diagnosing an abnormality of the power generation power supply unit PSU1, the output current of the power generation power supply unit PSU1 is limited. The power storage unit PSU2 is overcharged or overdischarged during the abnormality diagnosis. There is a risk of becoming. That is, during the abnormality diagnosis in which the output current of the power generation power supply unit PSU1 is limited, the required output to the vehicle power supply device 1 is greatly increased, so that the power taken out from the power storage power supply unit PSU2 is increased, so that the power storage power supply unit PSU2 Is over-discharged. Further, during the abnormality diagnosis in which the output current of the power generation power supply unit PSU1 is limited, the required output to the vehicle power supply device 1 is greatly reduced, so that the charging current to the power storage power supply unit PSU2 is increased, so that the power storage power supply unit is increased. PSU2 is overcharged. By carrying out step S23 so that the charge capacity SOC of the power storage unit PSU2 is in a suitable state, it is possible to suitably prevent the power storage unit PSU2 from being overcharged or overdischarged.

In step S24, when the charge capacity SOC of the power storage unit PSU2 is less than a predetermined third threshold value (YES) in step S22, the diagnosis unit 31 executes an abnormality diagnosis of the power generation power supply unit PSU1. Here, the abnormality diagnosis of the power generation power supply unit PSU1 of the vehicle power supply device 1 is executed based on the flowchart of FIG. Details of the abnormality diagnosis of the power generation power supply unit PSU1 will be described later.

In step S25, it is determined whether or not the abnormality diagnosis of the power generation power supply unit PSU1 executed in step S24 is completed. If the abnormality diagnosis is not completed (NO), step S25 is repeated. If the abnormality diagnosis is completed (YES), the process proceeds to step S26.

In step S26, it is determined whether the charge capacity SOC of the power storage unit PSU2 is less than the fourth threshold value. When the charge capacity SOC of the power storage unit PSU2 is less than the fourth threshold value (YES), the process proceeds to step S28, and the abnormality diagnosis of the power storage unit PSU2 is executed. When the charge capacity SOC of the power storage unit PSU2 is equal to or greater than the fourth threshold value (NO), the process proceeds to step S27.

In step S27, in step S26, when the charge capacity SOC of the power storage unit PSU2 is equal to or greater than the fourth threshold value (NO), the drive control unit 33 corrects the output current of the power generation power supply unit PSU1 to decrease. That is, in order to reduce the charge capacity SOC of the power storage unit PSU2, the output ratio of the power generation power supply unit PSU1 to the required output is reduced. Steps S26 and S27 are repeated until the charge capacity SOC of the power storage unit PSU2 becomes less than the fourth threshold value.

If the charge capacity SOC of the power storage unit PSU2 is not within an appropriate range when diagnosing an abnormality of the power storage unit PSU2, the storage power supply PSU2 becomes overcharged during the abnormality diagnosis in which the charging current of the power storage unit is limited to a constant current. There is a fear. That is, during the abnormality diagnosis in which the charging current of the storage power supply unit PSU2 is limited, the charging current continuously flows to the storage power supply unit PSU2, so that the charge capacity SOC exceeds a suitable upper limit value in the control of the storage battery and is excessive. It will be charged. By executing step S27 so that the charge capacity SOC of the power storage unit PSU2 is such that the abnormality diagnosis of the power storage unit PSU2 can be suitably performed, it is possible to suitably prevent the power storage unit PSU2 from being overcharged. It is possible.

In step S28, when the charge capacity SOC of the power storage unit PSU2 falls below a predetermined fourth threshold value (YES) in step S26, the diagnosis unit 31 executes an abnormality diagnosis of the power storage unit PSU2. Here, the abnormality diagnosis of the power storage unit PSU2 of the vehicle power supply device 1 is executed based on the flowchart of FIG. Details of the abnormality diagnosis of the power storage unit PSU2 will be described later.

In step S29, it is determined whether the abnormality diagnosis of the power storage unit PSU2 executed in step S28 is completed. If the abnormality diagnosis is not completed (NO), step S29 is repeated. When the abnormality diagnosis of the power storage unit PSU2 is completed (YES), the abnormality diagnosis in the second diagnosis mode is terminated.

(Abnormal diagnosis of power storage unit PSU2)
Next, the abnormality diagnosis of the power storage unit PSU2 executed by the diagnosis unit 31 in steps S12 and S28 of the flowchart of FIG. 3 will be described with reference to the flowchart of FIG.

In step S31, the diagnostic unit 31 instructs the drive control unit 33 to control the charging current I _N of the power storage power supply unit PSU2 to be diagnosed constant. The drive control unit 33 controls so that the current output by the power storage unit PSU2 becomes constant with the diagnostic current based on the instruction of the diagnostic unit 31.

In step S32, the drive control unit 33 detects an operation amount (also referred to as an accelerator opening degree) of an accelerator pedal (also referred to as an accelerator opening degree) (not shown). Further, in the case of a saddle-riding vehicle, a rider request may be made.

In step S33, the drive control unit 33 calculates the required output to the motor M based on the accelerator opening degree detected in step S32.

In step S34, the drive control unit 33 calculates the generated power output by the power generation power supply unit PSU1. That is, as the generated power of the power generation power supply unit PSU1, the required power P is determined in consideration of the required output calculated in step S33 and the diagnostic current of the storage power supply.

In step S35, the drive control unit 33 calculates and the current _{I M} to the output power generation power supply unit PSU1 based on the required power P obtained by the step S34, the instruction to the power supply unit PSU1.

In step S36, the internal resistance value of the power storage unit PSU2 is calculated. Here, the internal resistance value in the storage power supply unit PSU2 is calculated based on the plurality of voltage sensors VS5 each arranged in at least one battery cell BC and the voltage sensor VS4 connecting the positive electrode and the negative electrode of the storage battery. it can.

The internal resistance value is obtained by dividing the voltage drop by the current. The voltage drop is V5, which is the total value of the voltage on the battery cell BC side, that is, the voltage value detected by the voltage sensor VS5, and the voltage on the DC / DC converter unit DCU side of the component, that is, the voltage value V4 detected by the voltage sensor VS4. It is obtained by the difference with. Current is the output current I _M of the electric storage power as a diagnostic current. That is, the output current I _M of the electric storage power as a diagnostic current, a voltage value V4 to the voltage sensor VS4 detected, the sum is a V5 voltage value the voltage sensor VS5 detects, on the basis, based on the following equation The internal resistance value RC between the voltage sensor VS5 including the relay RL3 and the service plug SP and the voltage sensor VS4 is calculated.
RC = (V5 - V4) / I M ··· ( Equation 1)

Further, the voltage value used when calculating the internal resistance value may be the average value of the voltage values measured by the voltage sensor during a predetermined time. Therefore, it is possible to suitably calculate the internal resistance value of the power storage unit PSU2 even when the voltage value fluctuates during the abnormality diagnosis.

In step S37, it is determined whether a predetermined time has elapsed since the abnormality diagnosis of the power storage unit PSU2 started. If the predetermined time has elapsed (YES), the process proceeds to step S38. If the predetermined time has not elapsed (NO), the process proceeds to step S31 to continue the abnormality diagnosis. Further, in step S37, the completion of the abnormality diagnosis was confirmed based on the passage of time, but the process may proceed to step S38 based on the acquisition of the internal resistance value.

In step S38, it is determined whether or not the internal resistance value calculated in step 36 is increased by a predetermined value or more from the internal resistance value predetermined at the time of vehicle manufacturing. That is, it can be determined that an abnormality has occurred in the power storage unit PSU 2 when the internal resistance value at the time of manufacturing the vehicle is significantly increased. If the internal resistance value has increased by a predetermined value or more (YES), the process proceeds to step 39.

In step S39, when it is determined in step S38 that the internal resistance value has increased by a predetermined value or more (YES), an abnormality is caused to the driver from the display unit 34 such as an in-vehicle meter or the voice output unit 35 such as a speaker. Is notified, and the abnormality diagnosis of the power storage unit PSU2 is completed. The display unit 34 is not limited to an in-vehicle meter that can display the speed of the vehicle 100, and includes, for example, a display mounted on the vehicle 100 such as a navigation device and an indicator lamp indicating the state of the vehicle. Further, the voice output unit 35 includes a speaker provided in the vehicle-mounted meter and a speaker capable of outputting the voice output from the audio provided in the door. If the internal resistance value does not increase by more than a predetermined value (NO), the abnormality diagnosis of the power storage unit PSU2 is terminated.

Next, the timing chart of FIG. 5 showing changes in the output current I _N of the power storage power supply unit PSU2 during the abnormality diagnosis of the power storage power supply unit PSU2, in FIG. 6 showing the transition of the required power P output of the power supply system 1 the timing chart, the timing chart of FIG. 7 showing changes in the output current I _M of the power supply unit PSU1 be described.

Referring to the timing chart of FIG. 5 showing changes in the output of the power storage power supply unit PSU2, the vertical axis represents the current I _N input and output to power storage power supply unit PSU2, the abscissa indicates the time t. Current I _N 0 than the plus side (zero) indicates the discharge current from the power storage power supply unit PSU2, negative side indicates the charging current to the energy storage power supply unit PSU2.

Since electric power storage power supply unit PSU2 has a power supply to be abnormality diagnosis, the output current I _N is controlled to be constant.

With reference to the timing chart of FIG. 6 showing the transition of the output of the vehicle power supply device 1, the vertical axis represents the required power P output by the vehicle power supply device 1, and the horizontal axis represents the time t.

Here, the required electric power P output by the vehicle power supply device 1 changes so as to satisfy the required output from the driver.

Referring to the timing chart of FIG. 7 showing changes in the output of the generator power supply unit PSU1, the vertical axis represents the current I _M that is output from the power supply unit PSU1, the horizontal axis represents time t.

Here, the power generation power supply unit PSU1 outputs the sum of the diagnostic current used for the abnormality diagnosis of the power storage power supply unit PSU2 and the current satisfying the output requested by the driver. Therefore, it is possible to preferably execute the abnormality diagnosis of the PSU2 of the power storage unit even during traveling in which the output requested by the driver changes.

(Abnormal diagnosis of power generation power supply unit PSU1)
Next, the abnormality diagnosis of the power generation power supply unit PSU1 executed by the diagnosis unit 31 in steps S18 and S24 of the flowchart of FIG. 3 will be described with reference to the flowchart of FIG.

In step S41, the diagnostic unit 31 instructs the drive control unit 31 to control the output current I _M of the power supply unit PSU1 to be diagnosed constant. The drive control unit 33 controls the current output by the power generation power supply unit PSU1 so as to be constant with the diagnostic current based on the instruction of the diagnostic unit.

In step S42, the drive control unit 33 detects the accelerator opening degree.

In step S43, the drive control unit 33 calculates the required output to the motor M by the drive control unit 33 based on the accelerator opening degree detected in step S42.

In step S44, the output discharged from the power storage unit PSU2 is calculated. That is, the power discharged from the power storage unit PSU2 is determined to be the required power P in consideration of the required output calculated in step S43 and the diagnostic current discharged from the power generation power source.

In step S45, the drive control unit 33, a current _{I N} of energy storage power supply unit PSU2 outputs it is calculated. Here, the current _IN is controlled so as to satisfy the required power P calculated in step S44.

In step S46, the diagnostic unit 31 calculates the internal resistance value of the power generation power supply unit PSU1. Here, based on a plurality of current sensors VS1 each arranged in the fuel cell FC per unit and a voltage sensor VS2 connecting the positive electrode and the negative electrode of the fuel cell stack, the inside of the power generation power supply unit PSU1. The resistance value can be calculated.

That is, similarly to the internal resistance value RC, it is arranged between the voltage sensor VS1 and the voltage sensor VS2 based on the voltage value V1 detected by the voltage sensor VS1 and the voltage value V2 detected by the voltage sensor VS2. The resistance value RA including the relay RL1 arranged in the power generation power supply unit PSU1 and the relay RL2 is calculated based on the following equation.
RA = (V2-V1) / _IM ... (Equation 2)

Further, the diagnostic unit 31 is a power generation power supply unit arranged between the voltage sensor VS2 and the voltage sensor VS3 based on the voltage value V2 detected by the voltage sensor VS2 and the voltage value V3 detected by the voltage sensor VS3. The RB, which is the internal resistance value including the connection portion between the PSU 1 and the DC / DC converter unit DCU, is calculated based on the following equation.
RB = (V3-V2) / _IM ... (Equation 3)

Further, the voltage value used when calculating the internal resistance value may be the average value of the voltage values measured by the voltage sensor during a predetermined time. Therefore, it is possible to preferably calculate the internal resistance value of the power generation power supply unit PSU1 or the power storage power supply unit PSU2 even when the voltage value fluctuates due to factors such as running conditions during the abnormality diagnosis.

Next, the timing of Figure 10 showing a timing chart of FIG. 9 showing the transition of the output current I _M of the power supply unit PSU1 during the abnormality diagnosis of the power supply unit PSU1, the transition of the power P output from the vehicle power supply device 1 and charts, the timing chart of FIG. 11 showing changes in the output I _N of the power storage power supply unit PSU2 be described.

Referring to the timing chart of FIG. 9 showing changes in the output of the generator power supply unit PSU1, the vertical axis represents the current I _M which is output from the power generating power supply unit PSU1, the horizontal axis represents time t.

Since power supply unit PSU1 has a power supply to be abnormality diagnosis, the output current I _M is controlled to be constant.

With reference to the timing chart of FIG. 10 showing the transition of the output of the vehicle power supply device 1, the required power P output by the vehicle power supply device 1 changes so as to satisfy the required output from the driver.

Further, by adjusting the charge capacity SOC of the power storage unit PSU2 in advance, it is possible to set the diagnostic current output from the power generation power supply unit PSU1 to a more suitable state during the abnormality diagnosis of the power generation power supply unit PSU1. .. That is, by increasing the diagnostic current output from the power generation power supply unit PSU1, the amount of voltage drop increases, so that highly accurate diagnosis can be performed. Specifically, steps S14 to S17, or steps S22 and S23 described in the flowchart of FIG. 3 correspond to a step of adjusting the charge capacity SOC of the power storage unit PSU2 in advance.

Referring to the timing chart of FIG. 11 showing changes in the output of the power storage power supply unit PSU2, the vertical axis represents the current I _N input to or output from the energy storage power supply unit PSU2, the abscissa indicates the time t. Current I _N 0 than the plus side (zero) indicates the discharge current from the power storage power supply unit PSU2, negative side indicates the charging current to the energy storage power supply unit PSU2.

In other words, power storage power supply unit PSU2 determines a current I _N is output to meet the required output from the driver. That is, when the required output is small, the diagnostic current of the power generation power supply unit PSU1 is used for charging the power storage power supply unit PSU2. When the output requested by the driver is large, the power storage unit PSU2 discharges the current so as to be added to the diagnostic current of the power generation power supply unit PSU1. Therefore, it is possible to suitably perform the abnormality diagnosis of the power generation power supply unit PSU1 even during traveling in which the output requested by the driver changes.

In the present embodiment, in the abnormality diagnosis of the power generation power supply unit PSU1 and the storage power supply unit PSU2, the abnormality diagnosis by the combination of the two voltage sensors VS1 and VS2 and the combination of the other two voltage sensors VS4 and VS5 has been described in detail. It is also possible to perform an abnormality diagnosis regarding the connection portion between the power generation power supply unit PSU1 and the DC / DC converter unit DCU by combining the two voltage sensors VS2 and VS3.

As described above, the following table shows the target parts that can be diagnosed abnormally by combining voltage sensors.

Further, when the condition of the threshold value regarding the charge capacity SOC of the power storage unit PSU2 is described in detail at the time of executing the abnormality diagnosis in the present embodiment, the first threshold value, the second threshold value and the third threshold value are performing the abnormality diagnosis of the power generation power supply unit PSU1. It is a threshold value used for. First threshold, while controlling the output current I _M of the electric power generation source unit PSU1 constant required output from the driver is determined based on the state of charge SOC of the battery power supply unit PSU2 in the case of maintaining the maximum. That is, the first threshold value is the case where the amount of decrease in the charge capacity SOC of the power storage unit PSU2 is maximized, and is set so as not to fall below the lower limit of the controllable charge capacity SOC of the power storage unit PSU2. Therefore, it is possible to preferably suppress the deterioration of the performance of the power storage unit PSU2 and control the power storage unit PSU2.

The second threshold and the third threshold value, while controlling the output current I _M of the electric power generation source unit PSU1 constant, the required output from the driver to the state of charge SOC of the battery power supply unit PSU2 when maintained at 0 (zero) Determined based on. That is, the second threshold value and the third threshold value are the cases where the increase amount of the charge capacity SOC of the power storage unit PSU2 is maximized, and are set so as not to exceed the upper limit value of the controllable charge capacity SOC of the power storage unit PSU2. To. Therefore, it is possible to preferably suppress the deterioration of the performance of the power storage unit PSU2 and control the power storage unit PSU2.

The fourth threshold value is a threshold value used during the abnormality diagnosis of the power storage unit PSU2. The fourth threshold value is determined based on the state of charge SOC of the battery power supply unit PSU2 in the case of controlling the charging current I _N of the power storage power supply to the constant. That is, the fourth threshold value is a case where the charge capacity SOC of the power storage unit PSU2 increases with a predetermined increase amount, and is set so as not to exceed the upper limit value of the controllable charge capacity SOC of the power storage unit PSU2. .. Therefore, it is possible to preferably suppress the deterioration of the performance of the power storage unit PSU2 and control the power storage unit PSU2.

As described above, the setting of the threshold value used at the time of abnormality diagnosis has been described in detail. The following table summarizes the characteristics of each threshold value.

As described above, in the present embodiment, by changing the diagnosis mode according to the charge capacity SOC of the power storage unit PSU2, the change in the output requested by the driver during the abnormality diagnosis of the power generation power supply unit PSU1 can be dealt with. It is possible to prevent the power output from the power storage unit PSU2 from becoming insufficient. Therefore, it is possible to suitably carry out the abnormality diagnosis even in the traveling state where the required output with respect to the vehicle 100 changes. Further, when the abnormality diagnosis can be performed during traveling, the number of abnormality diagnoses in one driving cycle between one ignition on and one ignition off can be increased. That is, by increasing the number of abnormality diagnoses, it is possible to improve the diagnosis accuracy of the vehicle power supply device.

Further, in a saddle-riding vehicle or an electric wheelchair in which the output and capacity of the power generation power source and the storage power supply mounted on the vehicle 100 are not large, either the power generation power supply unit PSU1 or the storage power supply unit PSU2 is diagnosed according to the abnormality diagnosis of the power supply. When the output is limited, the area that can be traveled only by the output of the other power supply is very limited. Therefore, even if the power generation power supply or the power storage power supply is being diagnosed, the running area where the abnormality diagnosis can be performed is increased by changing the diagnosis mode according to the charge capacity SOC of the power storage power supply unit PSU2 so that the vehicle can run. It is possible.

Further, in the present embodiment, the first diagnostic mode and the second diagnostic mode are based on a predetermined diagnostic current output by the power generation power supply unit PSU1 or the storage power supply unit PSU2 regardless of the state of the charge capacity SOC of the power storage unit PSU2. It is possible to calculate the internal resistance value. By doing so, it is possible to perform an abnormality diagnosis while maintaining the output of a predetermined diagnostic current from the power source to be diagnosed during the abnormality diagnosis, so that the abnormality diagnosis can be performed even in a running state where the required output for the vehicle 100 changes. It is possible to carry out suitably.

Further, in the present embodiment, by changing the first diagnostic mode and the second diagnostic mode according to the state of the charge capacity SOC of the power storage unit PSU2, the outputs of the power generation power supply unit PSU1 and the power storage unit PSU2 are the diagnostic currents. It is possible to output the requested output from the driver even in the state limited to. By doing so, it is possible to suitably execute the abnormality diagnosis even in the traveling state where the required output for the vehicle 100 changes.

Further, in the present embodiment, it is possible to preferably prevent the power storage unit PSU2 from being overcharged or overdischarged due to charging or discharging associated with the abnormality diagnosis of the power generation power supply unit PSU1 or the power storage unit PSU2. By doing so, the state of the charge capacity SOC of the power storage unit PSU2 can be adjusted to a charge capacity suitable for the abnormality diagnosis of the power generation power supply unit PSU1, and the accuracy of the abnormality diagnosis of the power generation power supply unit PSU1 can be improved. is there.

Further, in the present embodiment, by carrying out the step of adjusting the charge capacity SOC of the power storage unit PSU2, overcharging or overdischarging of the power storage unit PSU2 can be prevented. This makes it possible for the power storage unit PSU2 to appropriately manage the charge capacity SOC during the abnormality diagnosis in accordance with the abnormality diagnosis of the power generation power supply unit PSU1 or the storage power supply unit PSU2. That is, it is possible to prevent the charge capacity SOC of the power storage unit PSU2 from exceeding the upper limit value in control or lower than the lower limit value in control during the abnormality diagnosis of the power generation power supply unit PSU1 and suppress the performance deterioration of the power storage power supply unit PSU2. And the power storage unit PSU2 can be preferably controlled.

Although embodiments of the present invention have been disclosed, it will be apparent to those skilled in the art that modifications may be made without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

1 Vehicle power supply device 31 Diagnosis unit 32 Decision unit 34 Display unit 35 Audio output unit 100 Vehicle PSU1 1st power supply (power generation power supply unit)
PSU2 2nd power supply (storage power supply unit)

Claims (6)

A vehicle power supply device having a first power source having a power generation function and a second power source having a power storage function.
A determination unit that separately determines the first power supply or the second power supply as a diagnosis target, and
A diagnostic unit that diagnoses abnormalities related to continuity abnormalities between the first power supply and the second power supply determined by the determination unit, and
With
The decision unit
A first diagnosis mode in which the first power supply is abnormally diagnosed after the second power supply is abnormally diagnosed.
A second diagnosis mode in which the first power supply is abnormally diagnosed and then the second power supply is abnormally diagnosed.
Have ,
The decision unit
When the charge capacity of the second power supply is less than the first threshold value set so as not to fall below the lower limit of the controllable charge capacity of the second power supply, the first diagnostic mode is selected and
When the charge capacity of the second power source is equal to or greater than the first threshold value, the second diagnostic mode is selected.
A vehicle power supply device characterized in that the diagnosis unit performs the abnormality diagnosis. The diagnostic unit measures the first power source or the second power source determined based on the diagnostic mode of the determination unit by charging or discharging the first power source or the second power source with a predetermined diagnostic current. The vehicle power supply device according to claim 1, wherein the abnormality diagnosis is performed based on the internal resistance value of the second power supply. The diagnostic unit
The charge capacity of the second power supply at the end of the abnormality diagnosis of the second power supply is the first threshold value before the first diagnosis mode is selected by the determination unit and the abnormality diagnosis of the first power supply is executed. If it is less than, the correction is made so as to increase the output current ratio of the first power supply to the required output required for the vehicle power supply device, and
Before the first diagnostic mode is selected by the determination unit and the abnormality diagnosis of the first power supply is executed, the charge capacity of the second power supply at the end of the diagnosis of the second power supply is the charge capacity of the second power supply. When the second threshold value is set so as not to exceed the upper limit value of the controllable charge capacity and is equal to or higher than the second threshold value larger than the first threshold value, the first power supply is used before the abnormality diagnosis is executed. 1. The vehicle power supply device according to claim 1 or 2 , wherein the correction is performed so as to reduce the output current ratio of the power supply. In the diagnostic unit, the second diagnostic mode is selected by the determination unit, and the charge capacity of the second power supply before the execution of the abnormality diagnosis of the first power supply is the upper limit of the controllable charge capacity of the second power supply. When it is equal to or higher than the third threshold value set so as not to exceed the value , the correction is performed so as to reduce the ratio of the output current of the first power supply to the required output required for the vehicle power supply device. The vehicle power supply device according to claim 1 or 2 . In the diagnostic unit, the second diagnostic mode is selected by the determination unit, and the charge capacity of the second power supply at the end of the diagnosis of the first power supply sets an upper limit value of the controllable charge capacity of the second power supply. The vehicle power supply device according to claim 4 , wherein the correction is performed so as to reduce the output current ratio of the first power supply to the required output when the threshold value is equal to or higher than the fourth threshold value set so as not to exceed the required output. .. A vehicle equipped with the vehicle power supply device according to any one of claims 1 to 5 , wherein the vehicle includes a display unit or an audio output unit, and the diagnostic unit outputs a diagnosis result to an occupant. A vehicle power supply device characterized by outputting to the display unit or the audio output unit so as to notify the vehicle.