JPH10248104A - Controller for electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To move an electric car at a short distance to a place where it gives no obstacle to another vehicle or pedestrians, whose running motor driving is limited by an output limitation means in order to prevent a battery from being damaged. SOLUTION: If a battery condition judgment means 26 detects an decrease in the voltage or residual capacity of a main battery 3, an output limitation means 27 limits the target power of a running motor 1 to prevent the main battery 3 from being damaged. When a D-range or an R-range is selected just after a main switch 8 is turned on, an urgent condition judgment means 28 judges that it is in an urgent condition until a short time elapses (for example, 10 seconds), and the output limitation of the running motor 1 by the output limitation means 27 is released by an output limitation releasing means 29. It is thus possible for an electric car to move a short distance without damaging the main battery 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling motor driven by an on-board battery, a battery state determining means for determining the state of the battery, and a battery state determining means which determines that the battery needs to be protected. The present invention relates to a control device for an electric vehicle including an output limiting means for limiting an output of a traveling motor at times.

[0002]

2. Description of the Related Art An electric vehicle that runs by driving a traveling motor with a vehicle-mounted battery protects the battery when the voltage of the battery falls below a predetermined value or when the remaining capacity of the battery falls below a predetermined value. In view of this, the output of the traveling motor is limited (for example, Japanese Patent Application No. 7-1 7-1).
67405).

[0003]

However, if the electric vehicle cannot run due to the limitation of the output of the traveling motor, it may obstruct other vehicles or pedestrians depending on the stop position. Need to be moved out of the way.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to limit the output of a traveling motor by an output limiting means so that a stopped electric vehicle can move for a short distance.

[0005]

According to the first aspect of the present invention, when the emergency state determining means determines an emergency state in which the driver temporarily requests the traveling motor to output, the output restriction canceling means outputs the output. Since the output restriction of the traveling motor by the restriction means is released, the traveling motor can be driven to move the electric vehicle to a place where it does not interfere.

According to the second aspect of the present invention, after the driver operates the travel instructing means to instruct the vehicle to travel, the driver operates the shift range selecting means to select the travel range for the first time. Until a predetermined time elapses, it is determined that the state is an emergency state, and the driving of the traveling motor is permitted.
The electric vehicle can be moved out of the way while avoiding battery damage. Even if the travel range is selected for the second time or later after the travel is commanded by the travel command means, the drive of the travel motor is not permitted, so that the travel motor is driven indiscriminately and the battery is not damaged.

According to the third aspect of the invention, when the driver operates the emergency operating means, the emergency operation is determined until a predetermined time elapses from the time, and the driving of the traveling motor is permitted. The electric vehicle can be moved out of the way while avoiding damage to the vehicle.
Since driving of the traveling motor is permitted only by operating the emergency operation means, the electric vehicle can be moved quickly.

The predetermined time in the invention described in claims 2 and 3 is a time during which the electric vehicle V can be moved from a place where other vehicles or pedestrians do not get in the way to a place where it does not get in the way. , Preferably about 10 seconds.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

FIGS. 1 to 7 show an embodiment of the present invention. FIG. 1 is a diagram showing an entire configuration of an electric vehicle, FIG. 2 is a block diagram of a control system, and FIG. 3 is a circuit configuration of an electronic control unit. FIG. 4 is a flowchart of a main routine, FIG. 5 is a first flowchart of an emergency state determination routine, FIG. 6 is a second flowchart of an emergency state determination routine, and FIG. 7 is a torque map in normal mode and economy mode. FIG.

As shown in FIGS. 1 and 2, a four-wheel electric vehicle V has a pair of left and right front wheels Wf as drive wheels to which torque of a traveling motor 1 composed of a three-phase AC motor is transmitted via a transmission 2. , Wf and a pair of left and right rear wheels Wr, Wr as driven wheels. For example, a main battery 3 of 288 volts mounted on the rear of the electric vehicle V
Is a contactor 4, a joint box 5, a contactor 4, and an inverter 6 constituting a power drive unit.
Is connected to the traveling motor 1 via the. For example, an electronic control unit 10 connected to a 12-volt sub-battery 7 via a main switch 8 and a fuse 9 is connected to an inverter 6 for controlling the driving torque and the regenerative torque of the traveling motor 1. In order to charge the sub-battery 7 with the power of the main battery 3, the battery charger 11 and the DC /
A DC converter 12 is provided.

[0012] high-pressure circuit connecting the main battery 3 and the inverter 6, i.e., the direct current of the inverter 6, a current sensor S ₁ for detecting the current I _PDU, and the voltage sensor S ₂ for detecting the voltage V _PDU The current I _PDU of the DC section of the inverter 6 detected by the current sensor S ₁ and the voltage V _PDU of the DC section of the inverter 6 detected by the voltage sensor S ₂ are input to the electronic control unit 10. Further, the motor rotation speed Nm detected by the motor rotational speed sensor S _3,
Accelerator opening sensor S provided on accelerator pedal 13
The accelerator opening theta _AP detected by _4, and the shift range R detected by the shift range sensor S ₅ provided on the shift lever 14, and the output signal of the emergency switch S ₆ is inputted to the electronic control unit 10.

The main switch 8 corresponds to an ignition switch of a gasoline-powered vehicle, and constitutes a travel command unit according to the present invention. The shift lever 14
Selects a drive range, a reverse range, a neutral range and a parking range, and constitutes a shift range selecting means of the present invention.

The inverter 6 has a plurality of switching elements, and converts a DC power of the main battery 3 into a three-phase AC power when the traveling motor 1 is driven by inputting a switching signal from the electronic control unit 10 to each switching element. The three-phase AC power generated by the traveling motor 1 is converted to DC power and supplied to the main battery 3 when the traveling motor 1 is driven (regeneration).

Next, the electronic control unit 1 will be described with reference to FIG.
The circuit configuration of 0 will be described.

The electronic control unit 10 includes a torque command value calculating unit 21, a target power calculating unit 22, and an actual power calculating unit 2.
3. comparing means 24, PWM control means 25, battery state determining means 26, output limiting means 27, emergency state determining means 2
8 and an output restriction canceling means 29.

The torque command value calculating unit 21 includes a motor rotation speed Nm detected by the motor rotational speed sensor S _3, the accelerator opening theta _AP detected by the accelerator opening sensor S _4, detected by the shift range sensor S ₅ Based on shift range R, a torque command value Q _TRQ that the driver intends to generate on traveling motor 1 is calculated based on a preset torque map.

The target power calculating means 22 should multiply the torque command value Q _TRQ calculated by the torque command value calculating means 21 by the motor speed Nm detected by the motor speed sensor S ₃ and supply the result to the traveling motor 1. Alternatively, a target power to be taken out of the traveling motor 1 by regeneration is calculated. The target power may be a positive value or a negative value. The positive target power corresponds to the case where the traveling motor 1 generates the driving torque, and the negative target power corresponds to the case where the traveling motor 1 generates the regenerative torque. Corresponding to

On the other hand, the actual power calculating means 23 calculates the current I _PDU of the DC part of the inverter 6 detected by the current sensor S ₁ ,
By multiplying the voltage V _{PD U} DC of the inverter 6 that is detected by the voltage sensor S _2, calculates the actual power input to the inverter 6. Similarly to the target power, the real power also has a positive value and a negative value. The positive real power corresponds to the case where the traveling motor 1 generates a driving torque, and the negative real power corresponds to the case where the traveling motor 1 generates a driving torque. Corresponds to the case where a regenerative torque is generated.

The target power calculated by the target power calculation means 22 and the actual power calculated by the actual power calculation means 23 are compared with the comparison means 2
4 based on the difference between the target power and the actual power calculated by the PWM control means 25.
Perform WM control. As a result, the operation state of the traveling motor 1 is feedback-controlled so that the actual power matches the target power.

The battery state judging means 26 calculates an available output power which can be output without damaging the main battery 3 based on the battery voltage, the remaining battery capacity, the battery temperature and the like. The output restricting means 27 includes the target power calculating means 2
2 is compared with the available output power calculated by the battery state determination means 26, and if the available output power is lower than the target power, the available output power is set as the target power, so that the traveling motor 1 To prevent the main battery 3 from being damaged. When the output limiting means 27 operates, the electric vehicle V can run only at a low speed, or stops when the outputable power of the main battery 3 is low.

The emergency state judging means 28 includes the main switch 8
Based of on the ON / OFF state and the shift range detected by the shift range sensor S _5, or emergency switch S
_The emergency state is determined based on the operation of ₆ . The emergency state is a state in which the electric vehicle V needs to be promptly moved while the output restricting means 27 is operating. When the emergency state determination means 28 determines the emergency state, the output restriction release means 29 releases the restriction of the target power by the output restriction means 27 for a predetermined time, and the electric vehicle V is in a state in which the electric vehicle V can travel until the predetermined time elapses. Become.

The above operation will be further described with reference to the flowcharts of FIGS.

First, step S of the main routine shown in FIG.
Detects the motor rotation speed Nm in the motor rotational speed sensor S ₃ in 1, for detecting the accelerator opening theta _AP in the accelerator opening sensor S _4. If the driver selects the normal mode by a switch (not shown) in step S2, a torque command value Q _TRQ is searched from the torque map of the normal mode in step S3 using the motor speed Nm and the accelerator opening θ _AP as parameters. Conversely, if the economy mode is selected, a torque command value Q _TRQ is searched from the torque map of the economy mode in step S4 using the motor speed Nm and the accelerator opening θ _AP as parameters. FIG. 7 shows a torque map in the normal mode and the economy mode. The torque command value Q _TRQ on the driving side of the traveling motor 1 is set to be 70% of the economy mode in the normal mode. Therefore, when the economy mode is selected, the output of the traveling motor 1 is slightly reduced, but the power consumption can be reduced.

In the following step S5, the emergency state determination means 2
In step 8, it is determined whether or not the vehicle is in an emergency state. The contents of step S5 will be described with reference to the subroutine of FIG.
First step S11 in the shift range sensor S ₅ with the detected shift range is the traveling range (i.e., drive range or a reverse range) is in, and if it becomes the first driving range time after turning ON the main switch 8 in step S12, In step S13, a timer is set.
From the setting of the timer to the time-up of the timer after the predetermined time has elapsed in step S14, it is determined in step S15 that the state is an emergency state. After the predetermined time has elapsed in step S14, the emergency state is determined in step S16. It is determined that it is not in the state.

In step S11, if the shift range is in a range other than the traveling range (ie, the neutral range or the parking range), or in step S11.
Even if the shift range is in the running range, step S1
In cases other than the case where the running range is not entered for the first time after the main switch 8 is turned on in Step 2, the timer has expired in Step S14 because the timer is not set in Step S13. Therefore, it is determined in Step S16 that the emergency state is not established. I do.

If it is determined in step S5 of the main routine that the state is not an emergency state, and if the battery state determination means 26 determines in step S5 that the main battery 3 is to be protected, the output limiting means is determined in step S7. 27
Restricts the output of the traveling motor 1 to prevent the main battery 3 from being damaged when driving the traveling motor 1 in step S8. The battery state determining means 26 determines that the voltage of each battery cell, which should be 12 volts, is 11 volts.
When the voltage drops below volts, when the remaining capacity of the main battery 3 drops below 30%, or when the battery temperature exceeds 40 ° C., it is determined that the main battery 3 is in a state to be protected.

If it is determined in step S5 that the state is not an emergency state, and if the battery state determination means 26 determines in step S6 that the main battery 3 is not in a state to be protected, it is determined in step S4 that it is in an emergency state. In such a case, the output restriction releasing means 29 releases the output restriction of the traveling motor 1 by the output restriction means 27.

As described above, even if the electric vehicle V is stopped because the output of the traveling motor 1 is restricted by the state in which the main battery 3 is to be protected, the main switch 8
Is turned off, then turned on again, and the shift lever 1
When 4 is operated to drive range or reverse range,
Since the output limitation of the traveling motor 1 is released until a predetermined time has elapsed from that time, if the distance is short, the electric vehicle V
Can be moved. Therefore, the electric vehicle V can be promptly moved from a place where it does not interfere with other vehicles or pedestrians to a place where it does not interfere, and at that time, the time during which the output limitation of the traveling motor 1 is released is set to a predetermined time. By limiting, the main battery 3 can be prevented from being damaged by excessive load. From such a viewpoint, the predetermined time is suitably about 10 seconds, but can be arbitrarily increased or decreased as needed.

[0030] The emergency state in addition to determining the operation state of the main switch 8 and the shift lever 14 can be determined based on the operation of the emergency switch S _6. Emergency switch S ₆ is not the ON / OFF switch is constituted by a push switch that outputs a signal at the moment of pressing the predetermined time from the moment of pushing it (for example, 10 seconds)
Is determined to be an emergency state, during which the output restriction of the traveling motor 1 is released and the electric vehicle V can move.

This will be described with reference to the flowchart of FIG. First it determines if operating the emergency switch S ₆ in step S21, until a timer is set in step S22, the timer after a predetermined period of time has elapsed in step S23 is time up, that it is an emergency state in step S24. If the emergency switch S ₆ has not been pressed in step S21, or after a predetermined time has elapsed even if the emergency switch S ₆ has been pressed, it is determined in step S25 that the vehicle is not in an emergency state.

[0032] Thus, by operating the emergency switch S _6, as compared with the case to operate the main switch 8 and the shift lever 14 moves the electric vehicle V to release the more quickly the output limitation of the traveling motor 1 be able to.

While the embodiments of the present invention have been described in detail above, various design changes can be made in the present invention without departing from the gist thereof.

For example, the time for releasing the output limitation of the traveling motor 1 is not limited to 10 seconds, and can be set as needed.

[0035]

As described above, according to the first aspect of the present invention, the emergency state determining means for determining the emergency state in which the driver temporarily requests the traveling motor for output, and the emergency state determining means. Output limiting means for releasing the output limitation by the output limiting means when an emergency condition is determined, so that the electric vehicle is stopped at a place where other vehicles or pedestrians are obstructed by the output limiting means. In an emergency,
The traveling motor can be temporarily driven to move the electric vehicle out of the way.

According to the second aspect of the present invention,
It is provided with travel command means operated by the driver, and shift range selection means operated by the driver, and the emergency state determination means is operated by the shift range selection means only after the travel is commanded by the travel command means. Since the emergency state is determined from when the traveling range is selected to when a predetermined time has elapsed, the driving of the traveling motor is permitted only for a predetermined time in an emergency, so that the electric vehicle is not obstructed while avoiding battery damage. Can be moved to location. In addition, even if the travel range is selected for the second time or later after the travel is commanded by the travel command means, the drive of the travel motor is not permitted, so that the travel motor is driven indiscriminately and the battery is not damaged.

According to the invention described in claim 3,
An emergency operation means operated by a driver is provided, and the emergency state determination means determines an emergency state from when the emergency operation means is operated until a predetermined time elapses. The drive of the motor can be allowed to move the electric vehicle out of the way while avoiding battery damage. In addition, since the driving of the traveling motor is permitted only by operating the emergency operating means, the electric vehicle can be moved quickly.

[Brief description of the drawings]

FIG. 1 is a diagram showing an entire configuration of an electric vehicle.

FIG. 2 is a block diagram of a control system.

FIG. 3 is a block diagram showing a circuit configuration of an electronic control unit.

FIG. 4 is a flowchart of a main routine.

FIG. 5 is a first flowchart of an emergency state determination routine.

FIG. 6 is a second flowchart of an emergency state determination routine.

FIG. 7 is a diagram showing torque maps in a normal mode and an economy mode.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Running motor 3 Main battery (battery) 8 Main switch (running command means) 26 Battery state judging means 27 Output limiting means 28 Emergency state judging means 29 Output restriction canceling means S ₅ Shift lever (shift range selecting means) S ₆ Emergency switch (Emergency operation means)

Claims (3)

[Claims] A traveling motor (1) driven by a vehicle-mounted battery (3), a battery state determining means (26) for determining a state of the battery (3), and a battery (3) provided by the battery state determining means (26). When it is determined that the protection of 3) is necessary, the traveling motor (1)
And an output limiting means (27) for limiting the output of the vehicle. An emergency state determining means (28) for determining an emergency state in which the driver temporarily requests the traveling motor (1) for output. And an output restriction canceling means (29) for canceling the output restriction by the output limiting means (27) when the emergency state is determined by the emergency state determining means (28). Control device. And wherein travel command means operated by a driver (8), becomes and a shift range selection means being operated by the driver (S _5), the emergency state determining means (2
8) determines that the emergency state is determined from the time when the travel range is selected by the shift range selecting means (S ₅ ) until the predetermined time elapses for the first time after the travel is instructed by the travel command means (8). The control device for an electric vehicle according to claim 1, wherein: 3. An emergency operation means (S ₆ ) operated by a driver, wherein said emergency state determination means (28)
Is characterized in that to determine the emergency state until a predetermined time elapses from the time when the emergency operating means (S ₆₎ is operated, the control apparatus for an electric vehicle according to claim 1.