JP2003344516A - Abnormality detector for current sensor and control system provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an abnormality detector for current sensor that can specify the type of the abnormal state of a current sensor. <P>SOLUTION: The CPU 4a of a battery controller 4 is classified into any one of a normal mode (CLR) in which the states of the current sensor 3 and the power source circuit 4b of the current sensor are discriminated as normal; an abnormal mode (ISNG) in which at least either one of the sensor 3 and the circuit 4b is discriminated as abnormal; a limited control mode 1 (LIMIT1) in which running is sufficiently possible, by limiting a control range although the power source circuit 4d does not function normally; and another limited control mode 2 (LIMIT2) in which the running is sufficiently possible by limiting the control range although the current sensor 3 does not function normally, based on the sensor power supply voltage supplied from the power source circuit 4b to the current sensor 3 and the sensor output voltage of the sensor 3. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current sensor abnormality detection device for detecting an abnormal state of a current sensor and a control system equipped with the device.

[0002]

2. Description of the Related Art Conventionally, as a device for detecting an abnormality of a current sensor, a technique disclosed in Japanese Patent Laid-Open No. 2000-206221 has been known. In the above conventional technique, when detecting an abnormality, the current flowing between the secondary battery and the load is detected by the current sensor, and the voltage of the secondary battery is detected by the voltage sensor. Then, when the detection value of the current sensor is zero, the voltage detected by the voltage sensor is
The current sensor is determined to be abnormal when the change rate changes at a predetermined value or more within a predetermined time over a predetermined number of times.

[0003]

However, the above-mentioned abnormality detecting device for the current sensor merely determines whether or not the current sensor is abnormal, and determines what kind of abnormality the abnormality is. Absent.

It is an object of the present invention to provide a current sensor abnormality detection device and a control system equipped with the device, which can specify what kind of abnormality the abnormal state of the current sensor is.

[0005]

A current sensor abnormality detecting device according to the present invention detects an abnormality of a current sensor for detecting a charging / discharging current of a secondary battery, and the specifying means is a sensor body of the current sensor. Based on the supplied power supply voltage and the output voltage of the sensor body, the state of the current sensor including the sensor power supply and the sensor body is specified as one of a plurality of forms. Further, in the control system according to the present invention, when the specifying unit specifies one of the plurality of forms, the limiting unit limits the output of the load to a range according to the specified form.

[0006]

According to the present invention, the following effects can be obtained. (1) Since the state of the current sensor can be specified in any of a plurality of forms by the specifying means, not only whether or not the current sensor is abnormal, but also what kind of abnormality is specified You can (2) Further, when the specifying unit specifies one of the plurality of forms, the output of the load is limited to a range according to the specified form, so the output of the load corresponds to the current sensor state. It is controlled to an appropriate value.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a current control system of a general electric vehicle (for example, an electric vehicle). This current control system is equipped with a current sensor abnormality detection device that detects the state of the current sensor. A load 2 is connected to the battery 1. As the secondary battery constituting the battery 1, for example, a lithium ion battery, a nickel-cadmium battery, a nickel-hydrogen battery, or the like is used. The load 2 is composed of a motor, an inverter, etc. mounted on the vehicle. In the powering mode in which the vehicle is driven by the driving force of the motor, the battery 1 is discharged and electric power is supplied to the motor of the load 2. On the other hand, in the regenerative mode, the battery 1 is charged by the regenerative electric power from the motor.

The charge / discharge current flowing through the battery 1 is detected by the current sensor unit 3. Electric power is supplied to the current sensor unit 3 from the power supply circuit 4b of the battery controller 4.
The power supply voltage of the power supplied from the power supply circuit 4b to the current sensor unit 3 is A / of the CPU 4a of the battery controller 4.
Detected by D1 port. 3a is a detection element of the current sensor unit 3, and the output of the detection element 3a is amplified by the amplifier 3b. The sensor output output from the current sensor unit 3 is detected by the A / D2 port of the CPU 4a.
In the example shown in FIG. 1, the power supply circuit 4b is the battery 1
Although it is provided in the battery controller 4 that controls the above, it may be provided separately from the battery controller 4.

The CPU 4a samples the voltage at the A / D1 port at regular intervals Ta. CPU4a
Performs arithmetic processing such as moving average, weighted average, and unit conversion on the sampled voltage data. The sensor power supply voltage (VISENP), which is the calculation result, is obtained for each constant period Ta as shown in FIG. Similarly, the CPU 4a
The voltage is sampled at the / D2 port every Tb for a certain period. The CPU 4a performs arithmetic processing such as moving average, weighted average, and unit conversion on the sampled voltage data. The sensor output voltage (VISENV), which is the calculation result, is obtained every fixed period Tb as shown in FIG. The current value flowing through the battery 1 is calculated based on this sensor output voltage (VISENV).

Returning to FIG. 1, ON / OF of the power supply circuit 4b
The F control is performed by the CPU 4a of the battery controller 4. The CPU 4a uses the calculated sensor power supply voltage (V
Based on ISENP) and the sensor output voltage (VISENV), it is determined which of the four modes the normal / abnormal state of the current sensor unit 3 and the power supply circuit 4b will be described later. Further, the battery controller 4 outputs to the vehicle controller 5 an instruction S1 for output limitation or regeneration limitation according to the determination result. Power is supplied to the CPU 4a from the power supply circuit 4c. Although not shown, the battery controller 4 includes a ROM and a RAM as a storage unit.

The vehicle controller 5 calculates a torque command value for the motor of the load 2 based on the detected values of the accelerator sensor 7 for detecting the accelerator operation amount, the brake sensor 8 for detecting the brake operation amount, and the vehicle speed sensor 9. The vehicle controller 5 includes a CPU 5a, a ROM 5b, a RAM 5c and the like for performing these various calculations and vehicle control.
Further, the vehicle controller 5 corrects the calculated torque command value based on the output limit instruction or the regeneration limit instruction transmitted from the battery controller 4. The corrected torque command value S2 is sent to the load 2. Reference numeral 10 is an indicator for displaying an abnormality of the current sensor, and 11 is an ignition switch (IGN-SW). When the ignition switch 11 is turned on, power is supplied from the power supply circuit 4b to the CPU 4a of the battery controller 4 according to an instruction from the vehicle controller 5.

<< Explanation of Operation of Battery Controller 4 >>
Next, load control according to the current sensor state, that is, the normal / abnormal state of the current sensor unit 3 and the power supply circuit 4b will be described with reference to the flowcharts of FIGS. FIG. 3 is a flowchart showing the main flow of the processing operation of the CPU 4a. The flowchart shown in FIG. 3 starts when the ignition switch 11 is turned on and power is supplied from the power supply circuit 4c to the CPU 4a.

In step S10, electric power is supplied from the power supply circuit 4b to the current sensor section 3. In step S20,
The voltage value of the A / D1 port is sampled as described above, and the sensor power supply voltage (VISENP) is detected. Step S3
At 0, the voltage value of the A / D2 port is sampled to detect the sensor output voltage (VISENV). In step S40, the sensor output voltage (VISEN) detected in step S30 is detected.
V), that is, the sensor output voltage at vehicle startup is stored as an initial value. Since the motor load is zero when the vehicle is started, the current value flowing through the battery 1 is zero. Therefore, the initial value is the offset of the current sensor.

In the example shown in the present embodiment, the current sensor unit 3 has a specification of a measured current range of ± 200 A and an output voltage of 2.5 ± 2 V, and the power supply circuit 4b has a specification of a power supply voltage of 5. It is assumed that the voltage is 0V ± 5%. If the current sensor unit 3 and the power supply circuit 4b are normal, step S3
At 0, a voltage of 2.5V is detected as the sensor output voltage,
This voltage value of 2.5 V is stored as the initial value. Here, the plus sign current value represents the charging current value of the battery 1 during regenerative control, and the minus sign current value represents the discharging current value during power running control.

In step S50, the current sensor state (states of the current sensor section 3 and the power supply circuit 4b) will be described later based on the sensor power supply voltage and the sensor output voltage detected in steps S20 and S30 and the map shown in FIG. It is determined which of the four forms to perform.
The four modes are the normal mode (CLR) in which the current sensor unit 3 and the power supply circuit 4b are normally functioning, and the severe limitation of the output regeneration control because at least one of the current sensor unit 3 and the power supply circuit 4b is abnormal. Abnormal mode (ISNG) that requires
And the power supply circuit 4b is not functioning normally, but limited control mode 1 (LIMIT1) in which traveling is sufficiently possible if the control range is limited.
And the current sensor unit 3 is not functioning normally, but the limit control mode 2 (LIMIT
2). Here, that the power supply circuit 4b is functioning normally means that a predetermined power supply voltage is being output.

The confirmation work in step S50 will be described with reference to FIGS. The map of FIG. 4 and FIG.
The table is stored in advance in a storage device (not shown) of the battery controller 4. In the map shown in FIG. 4, the vertical axis represents the sensor output voltage (VISENV) and the horizontal axis represents the sensor power supply voltage (VISENP). First, the detected sensor supply voltage (VISENP) is in the range OK1, CA1 and NG1.
Of which range is included. Next, when the sensor power supply voltage (VISENP) is included in the ranges OK1 and CA1, the detected sensor power supply voltage (VISENV) is the line L
1 is included in the range OK2 between the line L1 ′, is included in the range CA2 between the lines L1 and L2, or is included in the range CA2 between the lines L1 ′ and L2 ′, is illustrated above the line L2 or is above the line L2. It is determined whether it is included in a range NG2 below L2 'in the figure.

Then, using the table shown in FIG. 5, from the positions of the sensor output voltage (VISENV) and the sensor power supply voltage (VISENP) in the map of FIG. 4, the current sensor state is the normal mode (CLR) and the abnormal mode (ISNG). ), Limit control mode 1 (LI
Determine whether it is MIT1) or limit control mode 2 (LIMIT2). As can be seen from Fig. 5, both the sensor power supply voltage and the sensor output voltage are within the normal range (OK1, OK2)
If, then the current sensor state is determined to be normal mode (CLR). In addition, the sensor output voltage is within the normal range (OK
2), the sensor power supply voltage is outside the normal range,
In the case of A1), the current sensor state is limited control mode 1 (LI
Determined to be MIT 1). On the contrary, when the sensor power supply voltage is in the normal range (OK1) and the sensor output voltage is in the predetermined range (CA2) outside the normal range, the current sensor state is determined to be the limit control mode 2 (LIMIT2). . Note that the predetermined range CA
1 and CA2 are within the allowable range specified by the battery controller 4 side.

When the sensor power supply voltage is in the range NG1 or the sensor output voltage is in the range NG2, that is, one of the sensor power supply voltage and the sensor output voltage is in the predetermined range CA.
1 and CA2, the current sensor state is determined to be the abnormal mode (ISNG). Further, when the sensor power supply voltage is in the predetermined range CA1 and the sensor output voltage is in the predetermined range CA2, that is, when the deviation from the normal range is not so large but both the sensor power supply voltage and the sensor output voltage are out of the normal range. Also, the current sensor state is determined to be the abnormal mode (ISNG).

Using the classification of FIG. 5, for example, even in the same abnormal mode (ISNG), the sensor power supply voltage is in the range NG.
1 and the sensor output is in the range OK2,
The abnormal sensor state can be specified as the first mode in which the power supply circuit 4b is abnormal. Conversely, the sensor power supply voltage is in the range OK1
In addition, when the sensor output is in the range NG2, the sensor abnormal state can be specified as the second mode in which the current sensor unit 3 is abnormal. Further, in the limit control mode 1 (LIMIT1) which is the third form of the sensor abnormal state, the power supply circuit 4b cannot be determined to be completely abnormal, but it can be determined that there is an abnormal tendency. On the other hand, in the case of the limit control mode 2 (LIMIT2) which is the fourth mode of the sensor abnormal state, the current sensor unit 3 cannot be determined to be completely abnormal,
It can be judged that there is an abnormal tendency. In addition, when specified by the above-described first to fourth modes, the indicator 10
Is displayed according to the form.

Returning to the flowchart of FIG. 3, in step S60, it is determined whether or not the current sensor state determined in step S50 is the normal mode (CLR). If YES is determined in step S60, that is, if the current sensor state is the normal mode (CLR), step S60 is performed.
If 90 is determined, the process proceeds to step S70. In step S90, since it is determined that the current sensor state is normal, the normal control condition is set to the instruction condition of the output regeneration limit instruction S1 from the battery controller 4 to the vehicle controller 5. Here, the normal control condition is that the vehicle is controlled within the maximum output / recoverable electric power range of the load 2 and the battery 1. When the process of step S90 ends, the process proceeds to step S400.

On the other hand, steps S60 to S70
When the process proceeds to step S70, it is determined in step S70 whether the current sensor state is one of the limit control mode 1 (LIMIT1) and the limit control mode 2 (LIMIT2). If YES is determined in step S70, the process proceeds to step S100. On the other hand, if the current sensor state is the abnormal mode (ISNG) and NO is determined, the process proceeds to step S80. Step S
In 80, the control range is the maximum output of load 2 and battery 1.
The regenerative electric power range is set to 10% or less, and the limit range is set as the instruction condition of the output regeneration limit instruction. If the electric power during discharge is negative, the limit range is -10% to + 10%
Becomes In addition, in the present embodiment, the value is 10% or less, but the numerical value of the limiting condition is not limited to 10%. Step S8
If the setting of 0 is completed, the process proceeds to step S400.

When the process proceeds from step S70 to step S100, it is determined in step S100 whether or not the current sensor state is the limit control mode 1 (LIMIT1). If YES (LIMIT1) is determined in step S100, the process proceeds to step S300 and the limit control mode 1 (LIMIT
Set the control limit range in 1), and set the limit range as the output regeneration limit instruction condition. On the other hand, if NO (LIMIT2) is determined in step S100, step S100
In step 200, the control limit range in the limit control mode 2 (LIMIT2) is set, and the limit range is set as the output regeneration limit instruction condition. The detailed procedure regarding the setting processing in steps S200 and S300 will be described later. Then, in step S400, step S
The instruction condition (limit range) S1 set in 80, S90, S200, and S300 is transmitted to the vehicle controller 5, and the series of processes is ended.

(Detailed Description of Step S200) FIG. 6 is a flowchart showing a detailed processing procedure of step S200. In the limit control mode 2 (LIMIT2), the power supply circuit 4b
Is a control mode when it is determined that the current sensor unit 3 is operating normally but is abnormal. Step S2
At 10, the lower limit value of the current value flowing through the battery 1 is set. As described above, the minus current value is used as the discharge current value, so the maximum current value during discharge is set. In the present embodiment, the discharge side maximum measurement current value in the measurement current range (operation guarantee measurement range) of the current sensor unit 3 is used to set as in the following equation (1). As described above, when the measured current range of the current sensor unit 3 is ± 200 A, the lower limit value is set to −100 A when the set value is 50%. In the following description, the set value is 50%.

[Equation 1]     (Lower limit value) = (Maximum measured current value on discharge side) x (Set value) (1)

In the following step S220, the upper limit value of the current value is set according to the following equation (2). Since the maximum measured current value on the charging side is + 200A, the upper limit value is + 100A when the set value is 50%.

[Equation 2]     (Upper limit value) = (Maximum measured current value on charging side) × (Set value) (2)

In step S230, step S in FIG.
Read the initial value of the sensor output voltage stored in 40,
It is determined whether or not the initial value deviates to the minus side (discharge side) with respect to the normal output voltage = 2.5V. The normal output voltage is a sensor output voltage output from the current sensor unit 3 when the current is zero. Current sensor unit 3
Since the specification (sensor operation guaranteed output voltage) is 2.5 ± 2V, the normal output voltage is 2.5V. Step S
If it is determined in 230 that there is a shift to the discharge side, the process proceeds to step S240, and correction processing is performed for the upper limit value set in step S220.

FIG. 9 is a diagram for explaining the upper limit value correction in step S240. In FIG. 9, lines L11 and L12 show the characteristics of the current sensor unit 3, and the vertical axis of FIG. 9 shows the current value and the horizontal axis shows the sensor output voltage. Characteristic L11 shows the case where the current sensor unit 3 is in a normal state. Characteristic L
11, the sensor output voltage when the current value is −200V is 0.5V, and the sensor output voltage when the current value is + 200V is 4.5V. Further, the sensor output voltage when the current value = 0V is 2.5V.

On the other hand, the line L12 shows the actual characteristics of the current sensor section 3. In the characteristic L12, the sensor output value VISV when the current value is 0V is ΔV more negative (discharge side) than the sensor output value 2.5V in the normal state.
Just shifted. At this time, it is estimated that the operating range (for example, the range in which the linearity of the output voltage is maintained) is also shifted to the negative side according to the shift ΔV of the initial value to the negative side. Therefore, in step S240, step S22
The upper limit value + 100A set at 0 is further corrected to the negative side. Here, the correction amount is 20 A, and the corrected upper limit value is +80 A. It should be noted that the correction amount is the deviation ΔV
It may be set according to. When the correction process of step S240 is completed, the process proceeds to step S260.

On the other hand, if NO is determined in step S230, that is, if it is determined that the charging side is deviated to the charging side, the process proceeds to step S250 and the lower limit value set in step S230 is corrected. The battery characteristic in this case is as shown by line L13, which is deviated from the line L11 by ΔV on the charging side (plus side). Therefore, contrary to the case of the characteristic L11, it is estimated that the operating range is shifted to the plus side. In step S250, the lower limit value -100A set in step S210 is corrected by the correction amount 20A, and the corrected lower limit value is set to -80A. If the correction process of step S250 is completed, step S2
Proceed to 60.

In step S260, the limit range in limit control mode 2 (LIMIT2) is set according to the direction of deviation of the sensor output voltage initial value. That is, step S230
If it is determined to be on the discharge side in step S210, the lower limit value in step S210 and the corrected upper limit value in step S240 are used to obtain −1.
The limit range is set as 00A <current value <+ 80A. On the other hand, when it is determined to be the charging side in step S230, −80 A <current value <+100 A is calculated using the upper limit value of step S220 and the corrected lower limit value of step S250.
Set the limit range like. Normal control range-20
When 0A to + 200A is expressed as −100% to + 100%, the above-described respective limit ranges are −50% to + 40%,
It can be expressed as -40% to + 50%.

(Detailed Description of Step S300) FIG. 7 is a flowchart showing a detailed processing procedure of step S300. The limit control mode 1 (LIMIT1) is a control mode when it is determined that the current sensor unit 3 is operating normally but the power supply circuit 4b is abnormal. Step S3
In 10, the initial value of the sensor output voltage stored in step S40 of FIG. 3 is read, and it is determined whether the initial value is deviated to the minus side (discharge side) with respect to the normal output voltage = 2.5V. To do. If it is determined in step S310 that there is a shift to the discharge side, the process proceeds to step S320,
If it is determined that it is shifted to the charging side (NO), step S
Proceed to 350.

First, from step S310 to step S
The case of proceeding to 320 will be described. Step S32
At 0, first, the current value correction amount θ corresponding to the deviation of the initial value of the sensor output voltage is calculated by the following equation (3). Formula (3)
The normal sensor output voltage of is the above-mentioned normal output voltage =
It means 2.5 V, and θ <0 when the initial value is shifted to the discharge side. The lower limit value of the current value is expressed by the following equation (4) using the current value correction amount θ. The guaranteed operation current range is the absolute value of the measured current range of the current sensor unit 3 described above, and the guaranteed operation current range = | ± 200 A | = 200
It is A. However, the coefficient α is 0.5.

[Equation 3]     θ = (sensor resolution) x (initial value of sensor output voltage-normal sensor output voltage)                                                                 … (3)

[Equation 4] (Lower limit value) = (Sensor resolution) x (Coefficient α) x (Sensor output voltage initial value)                         -(Operation guaranteed current range-Current value correction amount θ) (4)

In step S330, the upper limit value of the current value is set. The upper limit value of step S330 is an upper limit value when the initial value of the sensor output voltage is shifted to the discharge side (minus side). In the limit control mode 1 (LIMIT1), it is determined that the current sensor unit 3 is operating normally, so the upper limit value is set to the upper limit value of sensor operation guarantee range = + 200A. In step S340, a value obtained by adding a predetermined value = 20A to the lower limit value set in step S320 is set as a corrected lower limit value.

FIG. 10 is a view showing the upper limit value, the lower limit value and the corrected lower limit value in the limit control mode 1 (LIMIT1), which is similar to FIG. Lines L11 and L in FIG.
12 has the same characteristics as those shown in FIG. Current value I
₁ indicates the lower limit value calculated by the equation (4). The current value I ₂ is the corrected lower limit value, which is 20 A higher than the lower limit value I ₁ of the equation (4). Control range is I ₂ to + 200A
Is.

On the other hand, if the initial value of the sensor output voltage deviates to the charging side (plus side), N is returned in step S310.
When it is determined to be O, the process proceeds to step S350. Step S3
At 50, the lower limit value of the current value is set to the lower limit value of the sensor operation guaranteed range = −200A. In the following step S360, the upper limit value of the current value is similarly calculated using the equation (4). That is, in the equation (4), when the left side is replaced with the upper limit value and the upper limit value is calculated, the coefficient α is set to 4.5.
And

In step S370, the limit range in the limit control mode 1 (LIMIT1) is set according to the deviation direction of the initial value of the sensor output voltage. That is, step S310
If it is determined to be on the discharge side in step S330, the upper limit value of step S330 = + 200A and the corrected lower limit value I of step S340.
2 is used to set the limit range such that I ₂ <current value <+ 200A. On the other hand, when it is determined in step S310 that the battery is on the charging side, the lower limit value in step S350 is −200.
Using A and the corrected upper limit value of step S360, -20
The limit range is set as 0A <current value <corrected upper limit value.

<< Explanation of Operation of Vehicle Controller 5 >> Next,
The operation of the vehicle controller 5 that receives the above-described limit range as the output regeneration limit instruction S1 will be described with reference to the flowchart of FIG. The process of the flowchart shown in FIG. 8 starts when the ignition switch 11 of FIG. 1 is turned on. In step S600, the vehicle state is detected based on the accelerator operation amount information from the accelerator sensor 7, the brake operation amount information from the brake sensor 8, and the vehicle speed information from the vehicle speed sensor 9. In step S610, a torque command value is calculated from the vehicle state detected in step S600.

In step S620, the limit range transmitted from the battery controller 4 as the output regeneration limit instruction S1 is detected. The limit range transmitted from the battery controller 4 is a limit range according to the current sensor state, and includes a normal mode (CLR), an abnormal mode (ISNG), a limit control mode 1 (LIMIT1) and a limit control mode 2 (LIMIT
It is one of 2). In step S630, it is determined whether the current value corresponding to the torque command value calculated in step S610 is within the limit range transmitted from the battery controller 4.

If it is determined in step S630 that it is within the limit range, the process proceeds to step S640 and the torque command value calculated in step S610 is output to the load 2 as it is.
On the other hand, if it is determined in step S630 that the output power is not within the limit range, the flow advances to step S670 to set the output limit. In step S670, if the current value corresponding to the calculated torque command value is larger than the upper limit value of the limit range, the upper limit value is set as the torque command value. On the contrary, when the current value corresponding to the calculated torque command value is larger than the lower limit value of the limit range, the lower limit value is set as the torque command value. Then, the set torque command value is output to the load 2, and the process proceeds to step S650.

In step S650, it is determined whether the limit range transmitted from the battery controller 4 corresponds to the abnormal mode (ISNG). If it is determined in step S650 that the mode is abnormal, step S660.
After proceeding to, the indicator 10 for displaying the current sensor abnormality is lit, and then the process returns to step S600. On the other hand, if it is determined in step S650 that the limited range does not correspond to the abnormal mode (ISNG), the process returns to step S600.

The embodiment described above has the following operational effects. (A) As shown in FIG. 5, based on the voltage range of the sensor output voltage and the voltage range of the sensor power supply voltage, the states of the current sensor unit 3 and the power supply circuit 4b in the current sensor state are
The normal mode, abnormal mode, limit control mode 1 and limit control mode 2 are classified. By using the classification of FIG. 5, not only whether or not the current sensor is in the abnormal state, but the abnormal state of the current sensor can be specified to the above-described first to fourth modes. Circuit 4
It is possible to specify which one of b has an abnormality. As a result, it becomes easy to appropriately deal with the abnormality of the current sensor.

(B) The vehicle controller 5 outputs the torque command value to the load 2 in consideration of the limit range concerning the output regeneration transmitted from the battery controller 4.
Is controlled within a predetermined limit range. Therefore, when there is an abnormality in the current sensor unit 3 or the power supply circuit 4b (abnormal mode) or when there is an abnormal tendency (limit control mode 1 or limit control mode 2), the limit is set according to each mode. It becomes possible to drive. For example, when the driver depresses a large amount of the accelerator pedal to accelerate suddenly and the output torque exceeds the operating range of the current sensor when the output torque is requested to the load 2, the output is limited so that it falls within the operating range. To

Although the above embodiment has been described by taking an electric vehicle as an example, the present invention can be applied to a hybrid vehicle and the like. Further, in the battery controller 4, the power supply circuit 4b and the power supply circuit 4c are separate circuits, but they may have the same configuration.

In the correspondence between the embodiment described above and the elements in the claims, the battery controller 4 constitutes a current sensor abnormality detecting device and the CPU 4a constitutes a specifying means. Further, the vehicle controller 5 corresponds to the limiting means. Note that the present invention is not limited to the above-described embodiments as long as the above-described characteristic functions and effects can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a current control system of an electric vehicle.

FIG. 2 is a diagram illustrating voltage sampling in a CPU 4a, in which (a) relates to a sensor power supply voltage,
(B) relates to the sensor output voltage.

FIG. 3 is a flowchart showing a main flow of a processing operation of a CPU 4a.

FIG. 4 is a diagram showing a relationship between four modes showing a current sensor state and a power supply voltage and a sensor output voltage.

FIG. 5 is a diagram showing a relationship between a power supply voltage range, a sensor output voltage range, and each mode.

FIG. 6 is a flowchart showing details of step S200 in FIG.

FIG. 7 is a flowchart showing details of step S300 in FIG.

FIG. 8 is a flowchart showing a processing operation of a CPU 5a of the vehicle controller 5.

9 is a diagram illustrating upper limit value correction in step S240 of FIG.

FIG. 10 is a diagram showing an upper limit value, a lower limit value, and a corrected lower limit value in limit control mode 1 (LIMIT1).

[Explanation of symbols]

1 battery 2 load 3 Current sensor section 4 Battery controller 4a, 5a CPU 4b, 4c power supply circuit 5 Vehicle controller 7 Accelerator sensor 8 Brake sensor 9 vehicle speed sensor 10 Indicator 11 Ignition switch

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tomonaga Sugimoto             Nissan, Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan             Inside the automobile corporation (72) Inventor Tsuyoshi Morita             Nissan, Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan             Inside the automobile corporation F-term (reference) 5G053 AA07 BA01 BA04 CA04 DA01                       EA01 FA05

Claims (4)

[Claims] 1. A current sensor abnormality detecting device for detecting an abnormality of a current sensor for detecting a charging / discharging current of a secondary battery, wherein a voltage range of a sensor output voltage output from a sensor body of the current sensor and a sensor power supply are Current sensor abnormality detection, characterized by including a specifying unit for specifying the state of the current sensor including the sensor main body and the sensor power supply to any one of a plurality of forms based on the voltage range of the output power supply voltage. apparatus. 2. The current sensor abnormality detection device according to claim 1, wherein the plurality of forms include a first form indicating an abnormality of the sensor power supply and a second form indicating an abnormality of a sensor body of the current sensor.
And a current sensor abnormality detection device. 3. The current sensor abnormality detection device according to claim 1, wherein the voltage range of the power supply voltage is a normal power supply voltage range, a first power supply voltage range exceeding the normal power supply voltage range, and the first power supply voltage. The voltage range of the sensor output voltage is divided into a second power supply voltage range exceeding the range, and the voltage range of the sensor output voltage exceeds the normal sensor output range, the first sensor output range exceeding the normal sensor output range, and the first sensor output range. A second sensor output range, wherein the plurality of modes are: (a) a first mode in which the voltage range of the power supply voltage is the second power supply voltage range and indicates an abnormality of the sensor power supply; b) a second mode in which the voltage range of the power supply voltage is the normal power supply voltage range and the voltage range of the sensor output voltage is the second sensor output range and indicates an abnormality of the sensor body; and (c) The above A third embodiment the voltage range is normal sensor output range above the voltage range of the source voltage a first power supply voltage range a and the sensor output voltage,
(d) A fourth aspect in which the voltage range of the power supply voltage is the normal power supply voltage range and the voltage range of the sensor output voltage is the first sensor output range. apparatus. 4. The current sensor abnormality detecting device according to claim 1, wherein the output of the load is specified when the specifying unit specifies one of the plurality of forms. A control system for a load driven by a secondary battery, comprising: a limiting unit that limits the range according to the form.