Vehicular control device

Abstract

To provide a vehicular control device that corrects a current value detected by a current sensor that detects at least either discharging currents or charging currents of a battery that supplies drive power supply to an instrument of a vehicle, which can correct the detected current value accurately.SOLUTION: An EFI-ECU 6 comprises a calculating part 6b that calculates a difference between a reference consumption current value preset as a current value that the ECU 6 consumes from a battery 2 and a current value detected by a current sensor 3 during operation of the EFI-ECU 6, and a correcting part 6c that corrects the current value detected by the current sensor 3, on the basis of the difference. The calculating part 6b calculates the difference when a power supply of a vehicle 1 is in an OFF state and in a stable state which is suitable for calculating the difference. The correcting part 6c corrects the current value detected by the current sensor 3 using a correction amount, where the correction amount is determined from an average value of differences calculated five times by the calculating part 6b.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a vehicle control device that corrects a current value detected by a current sensor that detects at least one of a discharging current and a charging current of a battery that supplies driving power to devices in the vehicle. [Background technology]

[0002] Generally, various devices related to the operation of a vehicle are driven by power supply from a battery. Since the capacity of the battery decreases due to the operation of various devices, when the capacity of the battery decreases to a predetermined value, a generator such as an alternator is driven to charge the battery. The remaining capacity of the battery is detected, for example, by using a current sensor connected to the battery. In this case, the discharge current is detected by the current sensor, and the total discharge amount for that period is calculated by integrating the discharge amount. Also, the charging current is detected by the current sensor, and the total charge amount for that period is calculated by integrating the charge amount. Then, the remaining capacity is obtained by adding and subtracting the total charge amount and the total discharge amount from the capacity of the battery before calculation. In such a configuration, the detection accuracy of the remaining capacity of the battery depends on the detection accuracy of the current sensor. Therefore, in the past, a technology has been proposed to improve the detection accuracy by correcting the value of a current sensor that detects the charge and discharge of the battery (Patent Document 1).

[0003] The current value detected by the above current sensor is easily affected by fluctuations in ambient temperature, and the temperature fluctuations are detected as detection errors. In addition, detection errors due to temperature fluctuations differ depending on the individual current sensor. In the battery remaining capacity measuring device described in Patent Document 1, when starting up a device powered by a battery, a power source for driving the device is applied to the current sensor before the battery is turned on. Here, the current value output from the current sensor when the power source is applied is taken as an actual offset value, and the current value of the current sensor at that time is corrected to zero. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 06-207973 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the technology described in Patent Document 1 mentioned above, when the power source for driving the device is applied to the current sensor to obtain the actual offset value, if electrical disturbances such as noise are superimposed on the transmission path, the actual offset value may deviate significantly from the original value.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a technology that can accurately correct a detected current value in a vehicle control device that corrects a current value detected by a current sensor that detects at least one of the discharge current and charge current of a battery that supplies driving power to vehicle equipment. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the vehicle control device of the present invention is a vehicle control device that corrects the detected current value of a current sensor that detects at least one of the discharge current and charging current of a battery that supplies power to the vehicle, and is equipped with a calculation unit that calculates the difference between a reference consumption current value that is preset as a current value consumed from the battery when the vehicle control device is operating and the current value detected by the current sensor when the vehicle control device is operating, and a correction unit that corrects the current value detected by the current sensor based on the difference, and the vehicle control device is operable even when the vehicle power supply is in an OFF state, the calculation unit calculates the difference when a predetermined condition is met that is set in advance as a condition when the vehicle power supply is in an OFF state and the vehicle is in a stable state suitable for calculating the difference, and the correction unit calculates the average value of the differences calculated by the calculation unit N times (N is a natural number greater than or equal to 2) and corrects the current value detected by the current sensor with the average value after calculating the average value. Effect of the Invention

[0008] According to this configuration, the current value detected by the current sensor is corrected by the average value of N differences, which is less susceptible to disturbances such as noise compared to a case where correction is performed by calculating the difference once. Therefore, the current value detected by the current sensor can be corrected with high accuracy. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic configuration diagram of a vehicle control device according to an embodiment of the present invention; [Diagram 2] 4 is a diagram showing a condition that triggers the EFI-ECU in FIG. 1 to calculate a difference between a reference current consumption value and an actual current consumption value. FIG. [Diagram 3] FIG. 11 is a diagram for explaining a method for determining a correction amount. [Figure 4] 4 is a flowchart showing an example of a current sensor correction amount determination process performed by the EFI-ECU of FIG. 1. [Diagram 5] 4 is a flowchart showing an example of an abnormality determination process performed by the EFI-ECU of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A battery charge / discharge system including a vehicle control device according to one embodiment of the present invention will be described with reference to Figures 1 to 5. Figure 1 is a schematic diagram of a battery charge / discharge system including a vehicle control device according to one embodiment of the present invention, Figure 2 is a diagram showing conditions that trigger the EFI-ECU of Figure 1 to calculate a difference between a reference current consumption value and an actual current consumption value, Figure 3 is a flowchart showing an example of a current sensor correction amount determination process executed by the EFI-ECU of Figure 1, and Figure 5 is a flowchart showing an example of an abnormality determination process executed by the EFI-ECU of Figure 1.

[0011] (Electrical configuration of the battery charge / discharge system) The battery charge / discharge system of this embodiment corrects the current value detected by the current sensor and then controls the charging means to control the charging / discharging of the battery, and is configured as shown in Fig. 1. That is, the battery charge / discharge system of this embodiment includes a battery 2 mounted on a vehicle 1, a current sensor 3 that detects the current value of the battery 2, a voltage sensor 4 that detects the voltage value of the battery 2, a charging means 5 that generates electricity for charging the battery 2, an EFI-ECU 6 that controls the operation of the charging means 5 and corrects the current value detected by the current sensor 3, a battery fluid temperature detection means 7, and an outside air temperature sensor 8.

[0012] The battery 2 (corresponding to the "battery" in the present invention) is, for example, a lead-acid battery, a lithium-ion battery, or an all-solid-state battery, and supplies driving power to various devices arranged in the vehicle 1, including the EFI-ECU 6 and the connection parts 10.

[0013] The current sensor 3 (corresponding to the "current sensor" of the present invention) is connected, for example, to the negative terminal of the battery 2, and distinguishes between the charging current flowing into the negative terminal of the battery 2 and the discharging current flowing out from the negative terminal of the battery 2. The discharging current value and the charging current value detected by the current sensor 3 are output to the EFI-ECU 6. Note that the discharging current and the charging current may be detected by separate current sensors.

[0014] The voltage sensor 4 is connected to the terminals of the battery 2 to detect a voltage value generated by the battery 2. The voltage value detected by the voltage sensor 4 is output to the EFI-ECU 6.

[0015] The charging means 5 is, for example, an alternator, which generates electricity for charging the battery 2. The charging means 5 operates based on a control signal from the EFI-ECU 6. Note that the charging means 5 is not limited to an alternator, and may be, for example, a dynamo or the like, as long as it generates electricity for charging the battery.

[0016] The battery fluid temperature detection means 7 is a means for detecting the temperature of the battery fluid. The battery fluid temperature detected by the battery fluid temperature detection means 7 is output to the EFI-ECU 6. The battery fluid temperature detection means 7 may be a temperature sensor that directly detects the fluid temperature of the battery 2, or may be a means that indirectly obtains the temperature of the battery fluid by, for example, estimating it based on the temperature of the engine coolant.

[0017] The outside air temperature sensor 8 detects the outside air temperature around the vehicle 1. The outside air temperature detected by the outside air temperature sensor 8 is output to the EFI-ECU 6.

[0018] The EFI-ECU 6 (corresponding to the "vehicle control device" of the present invention) controls the operation of the charging means 5 and calculates the remaining capacity of the battery 2 by correcting the current value of the battery 2 detected by the current sensor 3. The EFI-ECU 6 is a microcomputer equipped with a CPU that performs various calculations based on various control programs, a memory that stores various control programs and various data required for control, and the like. The EFI-ECU 6 is equipped with a charging control unit 6a that controls the remaining capacity of the battery 2 by controlling the operation of the charging means 5, a calculation unit 6b and a correction unit 6c that correct the detected current value of the current sensor 3, an abnormality management unit 6d that determines an abnormality in the battery 2, and a storage unit 6e that stores various data and the like. Here, the charging control unit 6a, the calculation unit 6b, the correction unit 6c, and the abnormality management unit 6d are each configured by a CPU, and the storage unit 6e is configured by a memory such as a ROM or a RAM. The EFI-ECU 6 is configured to be operable by receiving power from the battery 2 not only when the power of the vehicle 1 is ON (IG switch 9 is ON) but also when the power of the vehicle 1 is OFF (IG switch 9 is OFF). Below, the charging control of the battery 2 by the charging control unit 6a will be described, followed by the correction of the detected current value of the current sensor 3 by the calculation unit 6b and the correction unit 6c. Following the explanation of the correction of the detected current value of the current sensor 3, the abnormality determination of the battery 2 by the abnormality management unit 6d will be described.

[0019] (Battery charging control) The charging control unit 6a controls the operation / non-operation of the charging means 5 to control charging of the battery 2. In this embodiment, when the remaining capacity of the battery 2 becomes a predetermined value or less (for example, SOC≦90%), the charging means 5 is operated to charge the battery 2. When the remaining capacity of the battery 2 becomes a specific value (for example, SOC=100%) due to the operation of the charging means 5, the charging means 5 is stopped (deactivated) to stop charging the battery 2. Specifically, when the SOC becomes 90% or less, the charging control unit 6a transmits a control signal for operation to the charging means 5, and when the charging means 5 receives the signal, the charging means 5 operates and a charging current is supplied to the battery 2. When the SOC becomes, for example, 100%, the charging control unit 6a transmits a control signal for stopping the charging means 5, and when the charging means 5 receives the signal, the charging means 5 stops. The remaining capacity is the ratio of the remaining charge of the battery 2 at that time to the battery charge capacity at full charge (so-called SOC (State Of Charge)).

[0020] The charging control unit 6a manages the SOC, which indicates the remaining capacity of the battery 2, based on the amount of charge supplied from the charging means 5 and the amount of discharged from the battery 2 as follows.

[0021] First, regarding the charge amount, the charge control unit 6a acquires the current value (charge current value) of the charge current flowing into the battery 2 based on the detection signal of the current sensor 3. Then, by integrating the charge current value detected for a predetermined period, the amount of electricity (charge amount) required for charging during that period is calculated. The predetermined period is the update cycle of the SOC.

[0022] On the other hand, regarding the discharge amount, the charge control unit 6a acquires the current value (discharge current value) of the discharge current flowing out from the battery 2 based on the detection signal of the current sensor 3. Then, by integrating the discharge current value detected during a predetermined period (SOC update period), the charge control unit 6a calculates the amount of electricity (discharge amount) required for discharging during that period.

[0023] Then, the charging control unit 6a calculates the current remaining capacity of the battery 2 by adding the charge amount in the update period to the most recent remaining capacity of the battery 2 before the update and subtracting the discharge amount in the update period. The charging control unit 6a then calculates the SOC by dividing the calculated remaining capacity by the battery charge capacity at the time of full charge. The charging control unit 6a stores the calculated remaining capacity and SOC in a predetermined storage area of ​​the storage unit 6e. The predetermined storage area is updated at a predetermined update period.

[0024] According to such a method of calculating the SOC, the detection accuracy of the current sensor 3 affects the calculation accuracy of the discharge amount, charge amount, and SOC. In particular, if the calculated SOC is a value higher than the actual value due to the detection accuracy of the current sensor, the charging means will not operate even though it should. In this case, the insufficient capacity of the battery 2 may cause a malfunction in the vehicle equipment that supplies power.

[0025] To address this problem, it is possible to calculate the SOC while taking into account the detection error of the current sensor. For example, if the calculated SOC has an error of +2% due to the detection error of the current sensor 3, it is determined whether or not to operate the charging means 5 based on a value (SOC correction value) obtained by subtracting 2% from the calculated SOC. However, since there are individual differences in the error of current sensors, if a uniform SOC correction value is used for correction, it is necessary to use the current sensor with the largest error as the reference. In particular, it is necessary to use the current sensor with the largest error on the positive side of the actual value as the reference. The reasons for this are as follows.

[0026] That is, if the battery SOC is calculated to be higher than the actual SOC due to an error in the current sensor, the charging means will not operate even though the actual SOC is the value at which the charging means should operate. In this case, there is a possibility that a malfunction may occur in the equipment driven by the battery, which is problematic. Therefore, if the SOC correction value is made uniform for each vehicle, it will be adjusted to the maximum error on the positive side of the SOC among the errors of each current sensor. In that case, there will be many vehicles in which the charging means operates even though the SOC is at a value at which the charging means should not operate, resulting in poor fuel efficiency (electricity efficiency).

[0027] Therefore, in this embodiment, the problem of setting the SOC correction value uniform is solved by configuring the correction amount to be calculated for each individual current sensor. Also, the correction amount is set to an average value of multiple (five in this embodiment) differences described below, making the correction amount less susceptible to disturbances such as noise. Then, the charging control unit 6a calculates the SOC based on the current values ​​(corrected discharge current value, corrected charge current value) corrected by a correction unit 6c described below, and determines whether or not to send a control signal for operation to the charging means 5 based on the calculated SOC.

[0028] Next, the correction of the current value (discharging current value, charging current value) detected by the current sensor 3, which is performed by the calculation unit 6b and the correction unit 6c, will be described with reference to FIGS.

[0029] (Current value correction) In this embodiment, the correction amount of the current sensor 3 is determined once before the vehicle 1 is delivered, and after delivery, the correction amount is updated to a new correction amount at a predetermined opportunity.

[0030] (Current value correction before delivery) The calculation unit 6b (corresponding to the "calculation unit" of the present invention) calculates the difference between the reference current consumption value and the current value detected by the current sensor 3 in the test mode when the vehicle 1 is set in the test mode (the test mode state before the delivery of the vehicle 1). Here, the test mode state is a state in which only the EFI-ECU 6 is activated among various devices powered by the battery 2 of the vehicle 1. The reference current consumption value (corresponding to the "reference current consumption value" of the present invention) is a current consumption value required for the operation of the EFI-ECU 6, and is a value determined by design depending on the components of the EFI-ECU 6, the layout of the wiring pattern, and the like. The reference current consumption value is stored, for example, in a ROM constituting the storage unit 6e.

[0031] As described above, the EFI-ECU 6 operates by receiving power supply from the battery 2. Therefore, in the test mode state in which only the EFI-ECU 6 operates, the current value detected by the current sensor 3 should be the current value required for the operation of the EFI-ECU 6, i.e., the reference current consumption value. However, if the current sensor 3 has a detection error, the current value detected in the test mode indicates a value different from the reference current consumption value, and this difference can be regarded as the detection error. Therefore, the calculation unit 6b calculates the detection error of the current sensor 3 by calculating the above-mentioned difference.

[0032] The correction unit 6c (corresponding to the "correction unit" of the present invention) determines the difference calculated by the calculation unit 6b as the correction amount when correcting the error of the current value detected by the current sensor 3 thereafter, and stores the correction amount in a predetermined storage area (correction amount storage area 6e5) of the RAM constituting the storage unit 6e. After the correction amount is stored in the correction amount storage area 6e5, the correction unit 6c corrects the detection signal (discharge current value, charge current value) transmitted from the current sensor 3 with the correction amount stored in the correction amount storage area 6e5. The charging control unit 6a calculates the SOC based on the current value (discharge current value after correction, charge current value after correction) corrected by the correction unit 6c. For example, if the current value detected by the current sensor 3 is I1 [A] and the reference consumption current value is I2 [A], the difference is (I1-I2) [A], and if the value detected by the current sensor 3 thereafter is I3 [A], the SOC is calculated based on I3-(I1-I2) [A].

[0033] (Current value correction after delivery) When the IG switch 9 is OFF, i.e., when the power supply of the vehicle 1 is OFF, the calculation unit 6b calculates the difference (the difference between the reference consumption current value and the current value detected by the current sensor 3) when all of the conditions (a) to (f) shown in FIG. 2 (corresponding to the "predetermined conditions" of the present invention) are satisfied. In this embodiment, the calculation unit 6b also determines whether or not the conditions (a) to (f) are satisfied. Each of the conditions (a) to (f) is a condition under which it can be determined that the battery 2 is in a stable state suitable for detecting the current value. Each condition will be described below.

[0034] (a) Voltage [V] of battery 2 when IG switch (ignition switch) 9 is set to OFF > specified value [V] The condition (a) is a condition for determining whether the battery 2 is in a normal state. For example, if the voltage of the battery 2 when the IG switch 9 is OFF is equal to or lower than a predetermined value, it is possible that the battery 2 is degraded. In such a case, it is assumed that the current sensor 3 cannot detect an accurate current value, or the detected value varies greatly. Therefore, in this embodiment, the condition for calculating the difference is that the voltage of the battery 2 is equal to or higher than a predetermined value. The predetermined value [V] is stored in a predetermined storage area of ​​the ROM constituting the storage unit 6e.

[0035] (b) Battery fluid temperature A [℃] ≦ B [℃] The condition (b) is a condition for judging whether the battery 2 is in a state where it can perform normally. The performance of the battery 2 is affected by the temperature of the battery fluid. Therefore, a temperature range of the battery fluid is set in which the battery 2 can perform as desired. If the temperature is outside this range, it can be judged that the battery 2 cannot perform as desired. In this case, it is assumed that the current sensor 3 cannot detect an accurate current value, or the detected value varies greatly. Therefore, in this embodiment, the condition for calculating the difference is that the temperature of the battery fluid is within a predetermined temperature range. The temperature range of the battery fluid (A [°C], B [°C]) is stored in a predetermined storage area of ​​the ROM constituting the storage unit 6e.

[0036] (c) Outside temperature -C [℃] ≦ Battery fluid temperature ≦ Outside temperature +C [℃] The condition (c) is a condition for determining whether the battery 2 is in a stable state. During charging or discharging, a chemical reaction occurs in the battery fluid, and this reaction continues for a while even after the power supply of the vehicle 1 is turned off (the IG switch 9 is turned off). When the chemical reaction is occurring, reaction heat is generated, so the temperature of the battery fluid in this state indicates a value different from the outside air temperature. If a chemical reaction is occurring in the battery fluid, it is assumed that the current sensor 3 cannot detect an accurate current value, or the detected value varies widely. Therefore, in this embodiment, the condition for calculating the difference is that the temperature of the battery fluid is within a predetermined range with respect to the outside air temperature, that is, the chemical reaction is in a stable state in the battery fluid. The predetermined range (C [°C]) with respect to the outside air temperature is stored in a predetermined storage area of ​​the ROM constituting the storage unit 6e.

[0037] (d)G[h]≦IG-OFF time The condition (d) is set for the same purpose as the condition (c). That is, after the vehicle 1 is stopped (after the IG switch 9 is turned OFF), the chemical reaction in the battery fluid may not have subsided or other devices may be in operation for a while. In such a case, it is assumed that the current sensor 3 may not be able to detect an accurate current value or the detected value may vary widely. Therefore, in this embodiment, the condition for calculating the difference is that a predetermined time (G[h]: for example, 2[h]) or more has elapsed since the IG switch 9 was turned OFF. The predetermined time (G[h]) is stored in a predetermined storage area of ​​the ROM constituting the storage unit 6e.

[0038] (e) No history of battery failures The condition (e) is a condition for judging whether the battery 2 can exhibit normal performance. For example, if a failure was confirmed in the battery 2 in the past, it is doubtful whether the current value detected by the current sensor 3 indicates an accurate value. Therefore, in this embodiment, the condition for calculating the difference is that the battery 2 has no failure history. Note that a failure history of the battery 2 is recorded, for example, when the voltage drop of the battery 2 when the IG switch 9 is turned on exceeds a predetermined value. The failure history of the battery 2 is stored, for example, in a predetermined storage area of ​​the RAM constituting the storage unit 6e.

[0039] (f) EFI-ECU current consumption value (current value detected by current sensor 3) ≦ C [A] The condition (f) is a condition for determining whether or not devices other than the EFI-ECU 6 in the vehicle 1 are operating. As described above, the current consumption value (reference current consumption value) when only the EFI-ECU 6 is operating is known, so if the current value detected by the current sensor 3 is equal to or greater than the reference current consumption value when the IG switch 9 is in the OFF state, there is a possibility that a device other than the EFI-ECU 6 is operating. In this case, the current consumption value of the other device affects the difference, so that the detected current value of the current sensor 3 cannot be accurately corrected. Therefore, in this embodiment, the condition for calculating the difference is that the current value detected by the current sensor 3 is equal to or less than a predetermined value (D [A]). The predetermined value (D [A]) is, for example, a value slightly larger than the reference current consumption value, and is stored in a predetermined storage area of ​​the ROM constituting the storage unit 6e.

[0040] When the calculation unit 6b calculates the difference, it adds +1 to the value of a calculation number counter 6e1 (corresponding to the "calculation number counter" of the present invention) and resets an IG-OFF time timer 6e3 to 0. The calculation unit 6b also stores the calculated difference in a predetermined storage area (difference storage area 6e4) of a RAM constituting the storage unit 6e. In this embodiment, the difference storage area 6e4 can store five differences, and for example, the calculation number specifying which calculation has been performed and the difference calculated at that calculation number are stored in a linked state. The calculation number counter 6e1 and the IG-OFF time timer 6e3 are also managed in a predetermined storage area of ​​the RAM constituting the storage unit 6e.

[0041] Regarding management of the IG-OFF time timer 6e3, a timer management unit different from the calculation unit 6b may be provided in the EFI-ECU 6, and the IG-OFF time timer 6e3 may be managed therein. Also, the IG-OFF time timer 6e3 may be managed outside the EFI-ECU 6. In this case, when the IG-OFF time timer 6e3 becomes equal to or greater than G [h] (condition (d) in FIG. 2), the EFI-ECU 6 is started, and after the start-up, the calculation unit 6b of the EFI-ECU 6 may determine whether or not the remaining conditions (conditions other than (d) in FIG. 2) are satisfied.

[0042] When the value of the calculation number counter 6e1 becomes "5", that is, when the fifth calculation of the difference (corresponding to "N times" of the present invention) is performed, the correction unit 6c calculates the average value of the differences from the first to the fifth calculations and stores the calculated average value in the correction amount storage area 6e5. The average value is used as a correction amount when correcting the current value detected by the current sensor 3 after the calculation of the average value. Furthermore, when the correction unit 6c calculates the average value of the differences from the first to the fifth calculations, it resets the value of the calculation number counter 6e1 to "0" and resets the stored contents of the difference storage area 6e4.

[0043] The correction unit 6c corrects the detected current value output from the current sensor 3 with the correction amount stored in the correction amount storage area 6e5.

[0044] The determination of the average value (correction amount) will be specifically described with reference to FIG.

[0045] When all the conditions (a) to (f) are satisfied after the IG switch 9 of the vehicle 1 is set to the OFF state, the first calculation of the difference is performed. When the difference at this time is 0.1 [A], 0.1 [A] is stored in the difference storage area 6e4 as the average value of the first difference. Next, when all the conditions (a) to (f) are satisfied, the second calculation of the difference is performed. When the difference at this time is 0.2 [A], 0.2 [A] is stored in the difference storage area 6e4 as the average value of the second difference. Note that the calculation condition for the difference is G [h] ≦ IG-OFF time (d), and the IG-OFF time timer 6e3 is cleared when the difference is calculated. Therefore, the second calculation is performed at least after G [h] or more has elapsed since the first calculation. The third and subsequent calculations are performed in the same manner, and are performed at least after G [h] or more has elapsed since the previous calculation.

[0046] Then, if the third difference is 0.3 [A], the fourth difference is 0.1 [A], and the fifth difference is 0.2 [A], when the fifth difference is calculated, the correction unit 6c calculates the average value of the first to fifth differences and stores the average value in the correction amount storage area 6e5. That is, in this case, 0.18 [A], which is the average value of the first to fifth differences, is stored in the correction amount storage area 6e5.

[0047] At this time, the difference storage area 6e4 and the calculation number counter 6e1 are cleared. Therefore, the next time the value of the calculation number counter 6e1 becomes 5 is when the 10th difference is calculated, and the average value of the difference at this time is calculated by the correction unit 6c. That is, the average value of the 6th to 10th differences is calculated by the correction unit 6c. At this time, the correction unit 6c rewrites the stored content of the correction amount storage area 6e5 to the average value (updating the correction amount). The same applies to the 11th and subsequent calculations. That is, the average value of the five calculations is calculated, and the average value (correction amount) is sequentially updated as the correction amount when correcting the current value detected by the current sensor 3. Therefore, the correction amount storage area 6e5 stores the average value of the last five differences, and the detected current value of the current sensor 3 is corrected using the average value (correction amount). The correction is performed by the correction unit 6c.

[0048] (Abnormality judgment) In this embodiment, the difference calculated by the calculation unit 6b is used to manage whether the current sensor 3 is functioning normally or has an abnormality. The abnormality management unit 6d (corresponding to the "abnormality determination unit" of the present invention) performs the abnormality management. The difference is the difference between the current consumption value (reference current consumption value) required for the operation of the EFI-ECU 6 and the current value detected by the current sensor 3 as described above. Therefore, the difference indicates the amount of deviation between the design value of the current consumption value when only the EFI-ECU 6 is operating and the current value actually detected by the current sensor 3 at that time. Therefore, if the difference exceeds a predetermined range (X[A]≦the difference≦Y[A]), an abnormality in the current sensor 3 is expected. Therefore, in this embodiment, the abnormality management unit 6d manages whether the current sensor 3 is functioning normally or not based on the difference calculated by the calculation unit 6b. The predetermined range (X[A]≦the difference≦Y[A]) is stored in a predetermined storage area of ​​the ROM constituting the storage unit 6e.

[0049] Specifically, the abnormality management unit 6d judges whether the difference calculated by the calculation unit 6b is within a predetermined range (X[A]≦the difference≦Y[A]). If it is judged that the difference is not within the predetermined range, the abnormality management unit 6d increments the consecutive abnormality counter 6e2 by +1 (counts up). On the other hand, if it is judged that the difference is within the predetermined range, the abnormality management unit 6d does not count up the consecutive abnormality counter 6e2, but clears the value of the consecutive abnormality counter 6e2 to "0". The consecutive abnormality counter 6e2 is set in a predetermined storage area of ​​the RAM constituting the storage unit 6e.

[0050] Furthermore, when the value of the consecutive abnormality counter 6e2 becomes +2, that is, when the difference is not within the predetermined range (X[A]≦the difference≦Y[A]) for two consecutive times (corresponding to the "consecutive predetermined number of times" of the present invention), the abnormality management unit 6d determines that an abnormality has occurred in the current sensor 3, and sets the current sensor abnormality flag to ON. At that time, the abnormality management unit 6d executes a notification process to notify the abnormality of the current sensor. The notification process can be, for example, a process of turning on a fault warning light (so-called MIL lighting). The current sensor abnormality flag is set, for example, in a predetermined storage area of ​​the RAM constituting the storage unit 6e. Furthermore, the consecutive number of times that the abnormality management unit 6d determines that the current sensor 3 is abnormal is not limited to two times and can be changed as appropriate.

[0051] (Current sensor correction amount determination process) Next, a process for determining a correction amount when correcting the detected current value of the current sensor 3 (current sensor correction amount determination process) will be described with reference to Fig. 4. Fig. 4 is a flowchart showing an example of the current sensor correction amount determination process according to this embodiment. This process is performed by the calculation unit 6b and the correction unit 6c.

[0052] First, the calculation unit 6b judges whether or not all of the conditions (a) to (f) shown in Fig. 2 are satisfied (step S1). If it is judged that all of the conditions (a) to (f) are satisfied (YES in step S1), the calculation unit 6b calculates the difference and increments the count value of the calculation number counter 6e1 by +1 (step S2). On the other hand, if it is judged that at least one of the conditions (a) to (f) is not satisfied (NO in step S1), the calculation unit 6b ends the process.

[0053] After the process of step S2, the correction unit 6c judges whether the value of the calculation number counter 6e1 is "5" or not (step S3). If the value of the calculation number counter 6e1 is "4" or less (NO in step S3), the correction unit 6c resets the IG-OFF time timer 6e3 to "0" and ends the process (step S6).

[0054] On the other hand, when it is determined that the value of the calculation number counter 6e1 is "5" (YES in step S3), the correction unit 6c calculates the average value of the five differences and stores (updates) the average value in the correction amount storage area 6e5 as the correction amount for the current sensor 3 (step S4). The correction amount stored in the correction amount storage area 6e5 is used as the correction amount for the current value detected by the current sensor 3 thereafter. After calculating the average value, the correction unit 6c resets the calculation number counter 6e1 to "0" (step S4).

[0055] Then, when the process of step S4 ends, the correction unit 6c resets the value of the IG-OFF period timer 6e3 to "0" and ends the process (step S5).

[0056] (Abnormality determination process) Next, a process for determining whether or not the current sensor 3 is abnormal (abnormality determination process) will be described with reference to Fig. 5. Fig. 5 is a flow chart showing an example of the abnormality determination process according to this embodiment. The process is performed by the abnormality management unit 6d.

[0057] First, when the difference is calculated by the calculation unit 6b, the abnormality management unit 6d judges whether or not the difference is within a predetermined range (X[A]≦the difference≦Y[A]) (step S100). When it is judged in step S100 that the difference is within the predetermined range (X[A]≦the difference≦Y[A]) (YES in step S100), the abnormality management unit 6d resets the value of the consecutive abnormality counter 6e2 to "0" and ends the process (step S104).

[0058] On the other hand, when it is determined in the process of step S100 that the difference is not within a predetermined range (X[A]≦the difference≦Y[A]) (NO in step S100), the abnormality management unit 6d adds +1 to the value of the consecutive abnormality counter 6e2 (step S101). Following the process of step S101, the abnormality management unit 6d determines whether the value of the consecutive abnormality counter 6e2 has become "2" (step S102). Here, when it is determined that the value of the consecutive abnormality counter 6e2 has become "2" (YES in step S102), the abnormality management unit 6d performs an abnormality notification process such as turning on a fault warning light, and ends the process (step S103). On the other hand, when the abnormality management unit 6d determines in step S102 that the value of the consecutive abnormality counter 6e2 has not become "2" (NO in step S102), the abnormality management unit 6d ends the process.

[0059] Therefore, according to the embodiment described above, the calculation unit 6b calculates the difference between the reference current consumption value (current consumption value required for the operation of the EFI-ECU 6) and the current value detected by the current sensor 3. This calculation is performed when the power supply of the vehicle 1 is OFF (the IG switch 9 is OFF) and the vehicle is in a stable state suitable for calculating the difference (when the predetermined conditions (a) to (f) are satisfied). Since the power supply of the vehicle 1 is OFF, devices that are not activated during the OFF state (e.g., the connection part 10) do not consume the capacity of the battery. Therefore, the value of the current sensor 3 detected after the power supply of the vehicle 1 is OFF and the EFI-ECU 6 is activated corresponds to the current value consumed by the EFI-ECU 6. Therefore, the calculation unit 6b calculates the difference, thereby making it possible to calculate the detection error of the current sensor 3. Furthermore, since the difference is calculated during a stable state suitable for calculating the difference (when the predetermined conditions (a) to (f) are satisfied), the detection error of the current sensor 3 can be calculated with high accuracy.

[0060] Moreover, the correction unit 6c calculates the average value of the five differences, and after the calculation of the average value, corrects the current value detected by the current sensor 3 with the average value (correction amount). In this way, the current value detected by the current sensor 3 can be corrected with high accuracy, since it is less susceptible to disturbances such as noise compared to a case where correction is performed by calculating the difference once.

[0061] In addition, because the current value detected by the current sensor 3 is accurately corrected, the SOC calculated based on this is also highly accurate. As a result, unlike when the SOC of each vehicle is calculated using a common correction amount that takes into account the error of each current sensor 3, the charging means will not operate when it is not actually necessary, thereby improving fuel efficiency (electricity cost).

[0062] Furthermore, when the calculation counter 6e1 reaches five times, the correction unit 6c calculates the average value of the difference, and then clears the calculation counter 6e1 to "0" after the calculation of the average value. If the current sensor 3 deteriorates over time, the difference also changes, and if the calculation counter 6e1 is not cleared, the previously calculated difference may affect correction with an accurate correction amount (average value) based on the most recent difference. With this configuration, the calculation counter 6e1 is cleared when the calculation unit 6b calculates the difference five times, so the most recent five differences are reflected in the correction amount. This allows the current value to be corrected more accurately without being affected by past differences.

[0063] Furthermore, the abnormality management unit 6d judges that an abnormality has occurred when the difference does not fall within a predetermined range (X[A]≦the difference≦Y[A]) for two consecutive times. With this configuration, it is possible to judge whether the difference is abnormal or not. Furthermore, by judging that an abnormality has occurred for two consecutive times, an abnormality can be accurately judged.

[0064] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention. For example, in the above-described embodiment, the calculation unit 6b is configured to determine whether or not the conditions (a) to (f) (predetermined conditions) that serve as a trigger for calculating the difference are satisfied. However, a determination unit may be provided separately within the EFI-ECU 6 to perform the determination.

[0065] In the above embodiment, the calculation unit 6b calculates the difference when all of the conditions (a) to (f) are satisfied, but this is not limiting. For example, the difference may be calculated when any one of the conditions (a) to (f) is satisfied, or the difference may be calculated when any two or more of the conditions (a) to (f) are satisfied.

[0066] In addition, in the above embodiment, the average value of the five differences is used as the correction amount when correcting the detected current of the current sensor 3, but the number of times the difference multiplied by the average value is calculated is not limited to five and can be set arbitrarily to two or more times.

[0067] In the above embodiment, the current sensor 3 detects both the charging current supplied to the battery 2 and the discharging current discharged from the battery 2, and corrects both detected currents with a calculated correction amount, but for example, the current values ​​of the charging current and the discharging current may be detected using separate current sensors. In this case, the present invention can be applied to the correction of at least one of the two current sensors.

[0068] Furthermore, the present invention can be applied not only to electric vehicles but also to engine vehicles and hybrid vehicles.

[0069] Furthermore, the present invention can be adopted in various vehicle control devices that correct a current value detected by a current sensor that detects at least one of the discharging current and charging current of a battery that supplies driving power to equipment in the vehicle. [Explanation of symbols]

[0070] 2: Battery 3: Current sensor 6: EFI-ECU (vehicle control unit) 6b: Calculation part 6c: Correction section 6d: Abnormality management department (abnormality judgment department)

Claims

1. A vehicle control device that corrects a detected current value of a current sensor that detects at least one of a discharging current and a charging current of a battery that supplies power to a vehicle, a calculation unit that calculates a difference between a reference current consumption value that is preset as a current value consumed from the battery when the vehicle control device is in operation and a current value detected by the current sensor when the vehicle control device is in operation; a correction unit that corrects the current value detected by the current sensor based on the difference; Equipped with The vehicle control device is operable even when a power source of the vehicle is in an OFF state, The calculation unit calculates the difference when a predetermined condition is satisfied as a condition for a stable state suitable for calculating the difference when a power source of the vehicle is turned off, and The correction unit calculates an average value of N times (N is a natural number equal to or greater than 2) of the difference calculated by the calculation unit, and corrects the current value detected by the current sensor after the calculation of the average value with the average value. A vehicle control device comprising:

2. a calculation number counter that counts the number of times the difference is calculated by the calculation unit, When the calculation number counter reaches N, the correction unit calculates the average value, 2. The vehicle control device according to claim 1, wherein the calculation number counter is cleared after the correction unit calculates the average value.

3. An abnormality determination unit is provided, 3. The vehicle control device according to claim 1, wherein the abnormality determination unit determines that an abnormality has occurred when the difference does not fall within a predetermined range a predetermined number of times in succession.

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