JPH0646502A - Power supply interrupter for electric automobile - Google Patents

Abstract

PURPOSE:To interrupt driving power supply while sustaining driving of electric components such as headlights upon occurrence of abnormality in the electric system or when the possibility thereof is quite high. CONSTITUTION:DC power from a main power supply 14 is inverted through an inverter in a driver 24 into AC power for normally driving a DC brushless motor 13. Conditions of an electric vehicle are detected through a crash sensor which delivers crash detection signals Ja-Je to a diagnosis unit 21. The diagnosis unit 21 detects actual crash or abnormal conditions of a vehicle where crash is inevitable from the crash detection signals J and delivers a power supply interruption signal 22 to an interrupter 23. The interrupter 23 interrupts power supply from the main power supply 14 to the driver 24 through relays. The main power supply 14 is interrupted after main power supply current drops below a predetermined level.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power cutoff device for an electric vehicle, for example, when an abnormality occurs in the electric vehicle.
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power cutoff device for an electric vehicle that cuts off the power supply for driving the electric vehicle.

[0002]

2. Description of the Related Art In recent years, interest in the environment of the earth has increased, and social demands such as destruction of natural environment due to air pollution, global warming, and prevention of deterioration of living space due to noise have increased. Along with this, electric vehicles that do not use an internal combustion engine that causes exhaust gas as a drive source but drive a vehicle using clean electric power as a drive source have been attracting attention, and research and development have been widely conducted. This electric vehicle is equipped with a large-capacity drive power supply, and the electric power supplied from this drive power supply causes an electric motor to rotate to provide a driving force for the vehicle. By the way, Utility Model Publication No. 2-59
052 discloses a configuration in which the power supply from the battery to each part of the vehicle is shut off in the event of a collision. In addition, JP-A-58
Japanese Patent No. 22483 also discloses a configuration in which the power supply from the battery power source to each part of the vehicle is quickly cut off.

[0003]

However, all of the techniques described in these publications are intended for ordinary vehicles other than electric vehicles, and are used for vehicles using only a low voltage power source. To shut off. Therefore, in such an ordinary automobile, there is a problem in that it is impossible to drive other electric components such as tail lamps and headlights when the only power source is cut off. Therefore, an object of the present invention is to generate an abnormality in the electric system,
Alternatively, it is an object of the present invention to provide a power cutoff device for an electric vehicle that cuts off the drive power supply without affecting the control power supply when the possibility of occurrence is extremely high.

[0004]

According to a first aspect of the present invention, there is provided driving means for electrically generating at least a part of driving force of the vehicle, and a high-voltage driving power source for supplying power to the driving means. A control power supply for supplying a low-voltage power supply, an input / output control means for controlling the input / output of current between the drive power supply and the drive means using the control power supply as a power supply, and a state for detecting the state of the vehicle A detection sensor and the control power supply are used as power sources, and an abnormal state detection unit that detects an abnormal state of the vehicle from the output value of the state detection sensor and the control power source are used as power sources, and the abnormal state detection unit detects an abnormality in the vehicle. The power cutoff device for cutting off only the driving power supply when a state is detected is provided in a power cutoff device for an electric vehicle to achieve the above object. According to a second aspect of the present invention, the abnormal state detected by the abnormality detecting means in the power cutoff device for an electric vehicle according to the first aspect is a collision of the vehicle, an abnormal approach, a leakage of the driving power source, or a drive circuit including the driving power source. It is assumed that it is a short circuit.

According to the third aspect of the present invention, drive means for electrically generating at least a part of the driving force of the vehicle, high-voltage drive power supply for supplying power to this drive means, and low-voltage power supply are supplied. A control power source, an input / output control unit that uses the control power source as a power source, controls input and output of current between the drive power source and the drive unit, a state detection sensor that detects a state of a vehicle, and the control unit. Power supply for
An abnormal state detecting means for detecting an abnormal state of the vehicle from the output value of the state detection sensor, and the control power supply as a power source,
When an abnormal state of the vehicle is detected by the abnormal state detecting means, a command is given to the input / output control means to stop the input / output of electric current, and a power supply cutoff means for cutting off only the driving power supply. The above-mentioned object is achieved by providing the power cutoff device of an electric vehicle. According to a fourth aspect of the present invention, the power cutoff means in the power cutoff device for an electric vehicle according to the third aspect is directed to the input / output control means when the abnormal state of the vehicle is detected by the abnormal state detection means. A command is issued to stop the input / output of the current, and the drive power source is shut off after the current value falls below a predetermined value. According to a fifth aspect of the present invention, the power cutoff means in the power cutoff device for an electric vehicle according to the third aspect is directed to the input / output control means when the abnormal state of the vehicle is detected by the abnormal state detection means. A command is issued to stop the input / output of current, and the drive power supply is shut off after a predetermined time has elapsed from the command.

[0006]

In the power cutoff device for an electric vehicle according to the first aspect of the invention, the vehicle is driven by the driving means by the power source supplied from the driving power source, and the normal operation is performed. During this operation, the state detection sensor detects the state of the electric vehicle, such as a leak or an abnormal approach to an obstacle. Then, according to the detected abnormality, the power cutoff means such as the relay device cuts off only the output of the driving power supply. Therefore, when an abnormality occurs in the electrical system, only the drive source is shut off without shutting off the control power source, and other electrical components such as headlights cannot be driven due to the abnormality in the drive power source system. Is prevented. In the power cutoff device for an electric vehicle according to claim 3,
The abnormality detecting means detects the abnormality of the vehicle from the state of the vehicle detected by the state detection sensor. When an abnormality is detected, the power supply cutoff unit instructs the input / output control unit that controls the input / output of the current between the electric motor and the driving power supply to stop the input / output of the current, and Shut off. In this way, when the abnormality of the vehicle is detected, the drive power source alone is shut off together with the stop of the input / output between the electric motor and the drive power source, so that the drive power source can be easily shut down. It is prevented that other electric components such as the headlight cannot be driven due to a short circuit of the driving power system.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a power cutoff device for an electric vehicle according to the present invention will be described in detail below with reference to FIGS. FIG. 1 shows the arrangement of each part in an electric vehicle. As shown in this figure, the electric vehicle is provided with four drive wheels 12, 12, ... On the front, rear, left, and right sides of its main body 11, and each of these drive wheels 12 is an electric motor as a drive means for rotating each drive wheel. It is equipped with 13, 13 ,. The electric motor 13 is a brushless DC motor having a rotor made of 6-pole permanent magnets and an electromagnetic coil made of three-phase windings, that is, a stator coil. As an electric vehicle, in addition to the one in which a motor is provided in the wheel, for example, a motor is mounted on the vehicle body side and the wheels are driven through a differential gear, or a combination of an internal combustion engine and a motor is used. , Including those that drive wheels.

A main power source 14 as a driving power source is arranged at the rear of the main body 11. As the main power source 14, various secondary batteries such as a lead storage battery, a nickel-cadmium battery, a sodium-sulfur battery, a lithium secondary battery, a hydrogen secondary battery, and a redox type battery are used. The main power supply 14 is
For example, it is composed of a 240 [V] DC power supply, and is supplied to the electric motor 13 via a control unit 15 arranged in front of the main body 11. A main power supply circuit (not shown) configured by the main power supply 14 does not use the main body 11 as a power supply loop but constitutes an independent supply loop.
The control unit 15 converts the power supplied from the main power supply 14 into a three-phase alternating current by an inverter or the like, supplies predetermined electric power that matches the running conditions of the electric vehicle to the electric motor 13, and also supplies the main power supply 14 with power. Various controls such as shutting off are performed. The electric vehicle is equipped with an auxiliary power supply 17 under the rear seat 16. This auxiliary power supply 17 is
It is designed to supply current at a voltage of 12 [V],
It is used for operating a diagnostic device 21 and a controller 25, which will be described later, arranged in the control unit 15, operating wipers and car stereos, and illuminating various meters. The minus side of the auxiliary power source 17 is body-grounded, and an auxiliary power circuit (not shown) configured by the auxiliary power source 17 is configured with the main body 11 as a power supply loop.

Collision detection sensors 18 as state detection sensors are arranged at five locations on the main body 11 of the electric vehicle. The first and second collision sensors 18a and 18b are arranged in front of a side frame (not shown), the third collision sensor 18c is arranged in front of the passenger compartment 19 and the passenger seat 20, and the fourth and fifth collision sensors 18a and 18b are arranged. Collision sensors 18d, 18e
Is located behind the side frame. Each of these collision sensors 18 is an electric sensor that detects a collision by integrating a signal output from an acceleration system such as a strain gauge type or a piezo type, and a roller-shaped mass (an inertia for detecting deceleration due to a collision). Various collisions such as a roller mite type sensor in which a leaf spring is wound around a member), a spherical mass arranged in the cylinder detects the collision by the attractive force of the magnet and the viscous force of the air that passes through the gap between the cylinder, etc. A sensor is used. The collision sensors 18a to 18e may be sensors of the same type or different types, and in this embodiment, five roller mite type collision sensors are used.

FIG. 2 shows an external structure of the roller mite type collision sensor 18 used in this embodiment. As shown in FIG. 2A, the collision sensor 18 is
A roller-shaped mass 81 functioning as an inertial member is pressed to the right side in the drawing by a leaf spring 82 wound around the outer circumference of the roller-shaped mass 81. When the mass 81 receives deceleration due to a collision, it rotates to the left to close the switch 83 and the collision detection signal J is output. In addition, cell 8
By appropriately selecting the spring constant of the leaf spring 82 wound around 1, the degree of impact that outputs the collision detection signal J can be changed. In this embodiment, the collision sensor 18c disposed in the room between the driver's seat 19 and the passenger seat 20 outputs the collision detection signal Jc with a weaker impact than the other four collision sensors 18a, 18b, 18d, 18e. It has become.

In addition, as shown in FIG.
The first and second switches 83a and 83b in the rotation direction of
And the collision sensor 18 in which the width of the leaf spring 82 is widened on the way may be used. According to the collision sensor 18 configured in such two stages, the first switch 83a is closed when the collision force is comparatively weak, but the width of the leaf spring 82 of the second switch 83b is wide. , It cannot be closed due to the large spring constant. On the other hand, when a stronger impact force is received, the mass 81 moves further to the left, and the second switch 83b is closed. This allows
A collision detection signal J corresponding to the strength of the impact force is output.

FIG. 3 is a block diagram showing the structure of the control unit 15. As shown in this figure,
The diagnostic device 21 is provided as a collision diagnosing means for diagnosing whether or not a collision occurs based on the collision detection signals Ja to Je supplied from the individual collision sensors 18a to 18e. The diagnostic device 21 normally uses the auxiliary power source 17 as a power source and is backed up in case of a collision with a large-capacity capacitor such as an electric double layer capacitor. When the diagnostic device 21 diagnoses that a collision has occurred, the power shutoff signal 22 is supplied to the shutoff device 23 as power shutoff means.

The breaking device 23 is composed of an electromagnetic relay or the like,
The power supply of the main power supply 14 is supplied to the driver 24 during the normal operation of the electric vehicle, and when the power cutoff signal 22 is supplied from the diagnostic device 21, the electrical connection between both terminals of the main power supply 14 is cut off. . The circuit breaker 23 is arranged in the vicinity of the main power supply 14, and by connecting the input terminal of the circuit breaker 23 and the output terminal of the main power supply 14 with a wire as short as possible, a short circuit due to the wiring portion even in the event of a collision. Is being prevented.

The driver 24 is provided with an inverter circuit (not shown), converts the power supplied from the main power source 14 through the breaking device 23 into UVW-phase three-phase alternating current, and each stator coil (not shown) of the electric motor 13. Supply to the phase.
A drive signal 26 based on various signals output according to the operation of the driver or the like is supplied from the controller 25 to the driver 24. The driver 24 supplies a motor current 27 corresponding to the drive signal 26 from the main power supply 14 to the electric motor 13 as a drive current and also from the electric motor 13 to the main power supply 14 as a regenerative current. This controls the rotation speed of the electric motor 13 and the running state of the electric vehicle.

Although not shown, the controller 25 is a main computer composed of a well-known ROM (read only memory), RAM (random access memory), CPU (central processing unit), bus line such as data bus, and the like. It has a comprehensive control for driving an electric vehicle. That is, the accelerator signal e output from the accelerator sensor and corresponding to the amount of depression of the accelerator
1, a brake signal e2 output from the brake sensor corresponding to the amount of depression of the brake, a shift position signal e3 output corresponding to each range position of the shift lever,
A speed signal e4 obtained by electromagnetically picking up the rotation speed (rotation speed) of the electric motor and another signal e5 are supplied to the controller 25, and a drive signal 26 corresponding to each of these signals e is output.

FIG. 4 shows a schematic configuration of the diagnostic device 21, of which (a) is a collision sensor 18 shown in FIG.
When the one-stage collision sensor shown in (a) is used,
2 illustrates a schematic configuration of the diagnostic device 21. The diagnostic device 21 includes a four-input OR circuit 31 to which the collision sensors 18a, 18b, 18d, and 18e arranged at four positions before and after the main body 11 are supplied, the output of the OR circuit 31, and other indoor circuits. A two-input AND circuit 32 is provided to which the output of the collision detection sensor 18c that operates with a weaker impact than the sensor is supplied. By being configured in this way, the main body 1
1. Collision sensors 18a, 18 arranged at four positions before and after 1
When any one of b, 18d, and 18e and the collision sensor 18c arranged in the room output the collision detection signal J at the same time, the diagnostic device 21 determines that a vehicle collision has occurred and outputs the power cutoff signal 22. It is designed to output.

On the other hand, FIG. 4B shows the configuration of the diagnostic device 21 when the two-stage collision detection sensor 18 shown in FIG. 2B is used. This diagnostic device 21
Includes a 5-input OR circuit 33 in addition to the diagnostic circuit according to FIG. Then, in the collision sensor 18,
Each collision detection signal J output from the first switch 83a
a, Jb, Jd, and Je are supplied to the OR circuit 31, and Jc
Is supplied to the AND circuit 32. Further, the collision detection signals Ja ′ to Je ′ output from the second switch 83b are supplied to the OR circuit 33. In the diagnostic device 21 shown in FIG. 4B, the collision detection signal Ja 'from the second switch.
When any one of to Je 'is output, the power cutoff signal 22 is output.

FIG. 5 shows the configuration of the breaking device 23. As shown in this figure, the shutoff device 23 is connected to the main power source 1
It is provided with first and second relays 41 and 42 connected to the respective positive and negative output terminals of No. 4.
A contact is used as a contact of the first and second relays 41 and 42. The shutoff device 23 also includes a logical negation circuit 43 that inverts the power shutoff signal 22 supplied from the diagnostic device 21 to generate a low level signal. The output terminal of the logical NOT circuit is connected to one end of the resistor 44, and the other end of the resistor 44 is connected to the base of the transistor 45. The emitter of the transistor 45 is grounded, and the collector is connected to the power supply (Vcc) via the coil that operates the first and second relays. As this power supply, the main power supply 14 is used by dropping it to 12 [V] by a DC-DC converter, but an auxiliary power supply 17 may be used.

Next, the operation of the power cutoff device for an electric vehicle constructed as described above will be described. Note that FIG.
The two-stage collision sensor 18 shown in (b) and FIG.
It is assumed that the diagnostic device 21 shown in is used. (1) When the electric vehicle is operating normally In this case, since the mass 81 of each of the collision sensors 18a to 18e is pressed to the right side in the drawing by the leaf spring 82 wound around the outer circumference, Switch 83
a and 83b maintain the open state. Therefore, the high-level collision detection signal J is not output from each collision sensor 18, and the low-level signal is supplied to the diagnostic device 21. Then, the diagnostic device 21 also outputs a high-level power-off signal 2
2 is not output, but a low level signal is supplied to the interruption device 23. In the circuit breaker 23, the supplied low-level signal is inverted to the high-level signal by the logical NOT circuit 43 and supplied to the base, so that the transistor 45 operates and the A of the first and second relays 41 and 42 are operated. Activate the contacts. As a result, power is supplied from the main power source 14 to the driver 24, and normal operation is maintained.

(2) When an electric vehicle collides When an impact (deceleration) more than the spring constant of the leaf spring 82 is applied to the electric vehicle due to the collision, the mass 81 is left on the drawing (FIG. 2).
The switch 83a is rotated to close the switch 83a, and when a stronger impact force is applied, the switch 83b is closed. As a result, the collision detection signals Ja to Je from the respective collision sensors 18a to 18e.
Is output and supplied to the diagnostic device 21. And, for example, if the front right side of the electric vehicle collides with an obstacle,
Collision sensor 1 in front of the right side frame that receives the most impact
8a and the collision sensor 18c in the room are operated, and the high-level collision detection signal Ja and the collision detection signal Jc are supplied to the diagnostic device 21. Here, the collision sensor 18c arranged relatively far from the collision part also operates
This is because the spring constant until the mass 81 reaches the first switch 83a is set to be slightly weaker than that of the other collision sensors.

In the diagnostic device 21, the OR circuit 31 outputs a high-level signal when the collision detection signal Ja is supplied, and the AND circuit 32 outputs a high-level power-off signal 22 based on this signal and the collision detection signal Jc. It
On the other hand, when a strong impact force is applied to the electric vehicle, the second switch 83 is closed and the collision sensors 18a to 18e.
When the collision detection signals Ja 'to Je' are supplied from any one or more of the above, the OR circuit 33 outputs the high-level power cutoff signal 22.

The power cutoff signal 22 output from the diagnostic device 21 is supplied to the cutoff device 23, and is inverted by the logic NOT circuit 43 into a low level signal. Therefore, transistor 4
No current is supplied to the base of the transistor 5, and the transistor 45 is turned off. Therefore, the contacts of the first and second relays 41 and 42 are restored and the connection with the output terminal of the main power supply 14 is released. After the collision is detected by the collision sensor 18, the operation of returning the first and second relays 41 and 42 is instantaneously performed, and the wiring of the main power supply 14 is prevented from being short-circuited due to the collision.

In the embodiment described above, when the roller mite type collision sensor 18 shown in FIG. 2 (a) is used, the four collision sensors 18 arranged before and after the side frame are arranged.
Even if only one of a, 18b, 18d, and 18e operates, the power cutoff signal 22 is not output from the diagnostic device 21 and operates together with the collision sensor 18c whose spring constant is set to be slightly weaker than other collision sensors. Power off signal 2
Since 2 is output, malfunction can be prevented. Even if the collision sensor 18c does not operate, the four collision sensors 18a, 18b, 18d,
The diagnostic device 21 may be configured such that the power-off signal 22 is output even when at least two or more of the 18e operate. As a result, even if the collision sensor 18c fails, the diagnostic device 21 operates and safety can be ensured.

When the two-stage collision sensor 18 shown in FIG. 2B is used, any one of the collision sensors 1
Even when the second switch 83b in FIG.
2 is output. Therefore, the diagnostic device 21 can detect a collision corresponding to various situations. As described above, the type, the number of arrangements, and the arrangement locations of the collision sensors 18 are not limited to the configuration of the present embodiment, and various configurations can be adopted, and the collision detection signals J output from the respective collision sensors 18 can be used. The diagnostic device 21 can be configured to output the power shutdown signal 22 accordingly.

Next, the second embodiment will be described. Figure 6
Shows the structure of the control unit 15 and its surroundings in this embodiment. In this electric vehicle, an air bag 61 is arranged at the center of a steering wheel, and an emergency brake 62 for automatically applying braking in an emergency is arranged. Further, a distance measuring sensor 63 for measuring a distance to an obstacle existing in front of or behind the main body 11 is arranged at the center of the front and rear of the main body 11. The distance measuring sensor is adapted to measure the distance by a microwave or an optical radar (not shown).

On the other hand, a diagnosis device 64 as a collision diagnosis means.
Includes a CPU (not shown). The CPU has collision detection signals Ja to Je supplied from the collision sensor 18,
Various states of the electric vehicle are judged from the distance signal L supplied from the distance measuring sensor 63 and the speed signal e4.
Then, the power-off signal 22, the ignition signal 65 for igniting the airbag 61, and the emergency brake signal 66 are output according to the content of the determination. The above operation is performed according to the control program stored in the ROM (not shown).

The operation of the second embodiment thus constructed will be described with reference to the flowchart of FIG. The CPU of the diagnostic device 64 monitors for an abnormal approach between an electric vehicle and an obstacle such as a vehicle (step 1). Whether or not the vehicle is abnormally close is determined based on the speed signal e4 and the distance signal L supplied from the distance measuring sensor 63, based on whether or not the vehicle approaches within a predetermined distance corresponding to the speed of the electric vehicle. When it is determined in step 1 that the approach is abnormal (step 1; Y), the diagnostic device 64 outputs the emergency brake signal 66, and the emergency brake 62 automatically applies the brake (step 2).

The CPU further continues to monitor the state of the electric vehicle from the distance signal L and the speed signal e4, and further determines whether or not the collision cannot be avoided even by this emergency braking (step 3). When it is determined that the collision has been avoided by the emergency brake (step 3; N), the emergency brake is restored (step 4), and then the procedure returns to step 1 to continue monitoring the abnormal approach. On the other hand, if it is determined that the collision cannot be avoided (step 3; Y), the diagnostic device 64
The power supply cutoff signal 22 is supplied to the cutoff device 23 to cut off the main power supply 14 (step 5).

Thereafter, the CPU of the diagnostic device 64 monitors the supply of the collision detection signal J from the collision sensor 18 and determines whether or not a collision has occurred (step 6). When it is not determined that a collision has occurred even after a predetermined time has passed (step 6;
N) After assuming that the collision has been avoided by emergency braking, steering operation, etc., the main power supply 14 is restored (step 7), and then the procedure returns to step 1 to continue monitoring the abnormal approach. On the other hand, when it is determined from the collision detection signal J that a collision has occurred (step 6; Y), the diagnostic device 64 outputs the ignition signal 65 to operate the airbag 61 (step 8), and ends the process.

As described above, according to the second embodiment, the air bag 61, the emergency brake 62, and the distance measuring sensor 63 are provided.
Since it is provided with appropriate processing depending on the state of the electric vehicle, it is possible to further secure safety. It should be noted that all of the air bag 61, the emergency brake 62, and the distance measuring sensor 63 may not be arranged, but one or more of them may be arranged.

Next, a third embodiment corresponding to the power cutoff device for an electric vehicle according to claim 2 will be described. Figure 8
Shows a circuit configuration of the control unit 15 and its peripherals of the power cutoff device for an electric vehicle in the third embodiment. To simplify the description, the same parts as those in the first embodiment will be designated by the same reference numerals and the description thereof will be appropriately omitted. In the third embodiment, the main power source 14 corresponds to the power source for driving the electric motor, and the driver 34
The controller 25 corresponds to the input / output control means, the collision detection sensor 18 corresponds to the state detection sensor, and the diagnostic device 71
Corresponds to a part of the power cutoff means and the abnormality detection means, and the cutoff device 23 corresponds to a part of the power cutoff means.

The power cutoff device of this electric vehicle is equipped with a diagnostic device 71 as an abnormality detecting means. The diagnostic device 71 is supplied with the collision detection signals Ja to Je output from the five collision sensors 18a to 18e, and the drive signal 26 output from the controller 25 and the main power supply current 72 of the main power supply 14 are supplied. Is supplied. The motor current 27 is also supplied to the diagnostic device 71. The diagnostic device 71 includes a CPU (not shown), detects a collision from the collision detection signals Ja to Je, and detects other abnormalities such as a leakage and a short circuit from the drive signal 26 and the main power supply current 72. Detection of electric leakage and short circuit in the diagnostic device 71 is performed by comparing the levels of the drive signal 26 and the main power supply current 72 of the drive power supply. Then, when an abnormality is detected, the diagnostic device 71 supplies the power shutoff signal 22 to the shutoff device 23 and at the same time detects the abnormality detection signal 7
3 is supplied to the controller 25. The above operation is performed according to the control program stored in the ROM (not shown) of the diagnostic device 71. The diagnostic device 71 detects a collision by the diagnostic circuit shown in FIG. 4 and includes a detection circuit (not shown) for detecting various abnormal states other than the collision such as an electric leakage and a short circuit. Leakage or short circuit may be detected by comparing the levels of the output 27 of the driving power source.

In the first and second embodiments, by releasing the first and second relays 41 and 42 (FIG. 5), the main power supply circuit including the main power supply 14 which is a high voltage power supply is opened. It is like this. However, it may be difficult for the electromagnetic relay to release the contact when a large current is flowing. This is because an arc may be generated when the contact is released and the contact may be welded.
On the other hand, in the third embodiment, when an abnormality is detected by the diagnostic device 71, the driver 34 as the input / output control means and the controller 25 can input and output the current between the electric motor 13 and the main power supply 14. The main power supply 14 is cut off by operating the breaking device 23 while stopping. That is, when abnormalities of various vehicles are predicted,
Whether it is a drive current or a regenerative current due to regeneration, the supply of current to the electric motor 13 or the regeneration from the electric motor 13 to the main power supply 14 is stopped, and the first and second relays 41, By opening 42,
Prevents contactor welding. The command to stop the input / output of the current between the electric motor 13 and the main power supply 14 is performed by the abnormality detection signal 73 output from the diagnostic device 71.

FIG. 9 shows the details of the operation in the third embodiment. CPU of diagnostic device 71
Monitors whether an abnormality has occurred in the electric vehicle (step 11). That is, the CPU of the diagnostic device 71
Detects a collision based on each of the collision detection signals Ja to Je supplied from the collision sensors 18a to 18e, and compares the drive signal 26 supplied from the controller 25 with the level of the main power supply current 72 to cause a short circuit, Detects various abnormalities such as electric leakage. In the diagnostic device 71, when an abnormality is detected (step 11; Y), the abnormality detection signal 73 is output to the controller 25 (step 12). In the controller 25, when the abnormality detection signal 73 is supplied, the drive signal 2 having a value at which the motor current 27 between the driver 24 and the electric motor 13, that is, the drive current or the regenerative current becomes “zero”.
6 is output (step 13). As a result, the driver 24 makes the drive current from the main power source 14 to the electric motor 13 or the regenerative current from the electric motor 13 to the main power source 14, that is, the motor current 27 in accordance with the drive signal 26 to “zero”. . As a result, the main power supply current 7 supplied from the main power supply 14 to the driver 24 via the breaking device 23 is increased.
2 also becomes "zero".

On the other hand, in the diagnostic device 71, after outputting the abnormality detection signal 73 in step 12, the motor current 27
Is being monitored (step 14). This motor current 27
Is below a predetermined value, that is, a predetermined value at which the contacts of the first and second relays 41 and 42 of the breaking device 23 are not welded even if they are opened (step 14; Y), the breaking device 23
Is operated (step 15), and the process ends. That is, the diagnostic device 71 outputs the power cutoff signal 22 to the cutoff device 23. When the power cutoff device 22 is supplied, the breaker 23 shuts off the main power supply circuit 14 in the same manner as in the first embodiment.

In the third embodiment described above, the power-off signal 22 is output from the diagnostic device 71 on condition that the motor current 27 has become less than or equal to the predetermined value in step 14, but the following is done. May be. In other words, the diagnostic device 71 outputs the abnormality detection signal 73 and, after a lapse of a predetermined time, activates the breaking device 23 to disconnect the main power supply 14. The diagnostic device 71 is provided with a timer for this purpose, and although not shown, step 14 is replaced by operating the timer at the same time as the output of the abnormality detection signal 73 (step 14 '), and monitoring the elapse of a predetermined time (step 14 "). The power-off signal 22 is output after a predetermined time has elapsed.

In the third embodiment, after the abnormality detection signal 73 is output from the diagnostic device 71, it is monitored whether or not the motor current 27 is below a predetermined value. The value of the main power supply current 72 may be monitored in order to monitor the value of the current flowing through the relays 41 and 42 of 23.

As described above, according to the third embodiment, when the diagnostic device 71 detects a vehicle abnormality, the shutoff device 23 shuts off the main power source 14 between the driver 24 and the electric motor 13. This is performed together with the stop of the motor current 27. As a result, in this embodiment, the contacts of the relays 41 and 42 of the breaking device 23 can be opened without generating an arc. Particularly, in the third embodiment, after the abnormality detection signal 73 is output from the diagnostic device 71, it is confirmed that the motor current 27 has become a predetermined value or less, and in the modification of the third embodiment. After outputting the abnormality detection signal 73, after confirming the elapse of a certain period of time by the timer, the power cutoff signal 22 is output and the cutoff device 23 is operated. As a result, the contacts are opened after the currents of the relays 41 and 42 of the breaking device 23 become “zero” or a small current value, so that the contacts can be surely opened.

In each of the above-described embodiments, the main power supply 14 is completely shut off when it is determined that an electric vehicle is in a collision or in a state where collision cannot be avoided, or when an abnormality is detected. However, the present invention is not limited to this, and a part of the main power supply 14 may be cut off. For example, the power supplied to the driver 24 may be cut off by a collision, and the power supplied to the power steering or the like may not be cut off by a collision. This makes it possible to further secure safety.

Further, in each of the embodiments described above, the electric vehicle in which all of the driving force is generated by the electric power from the main power source has been described. The present invention may be applied to an electric vehicle that is generated by the internal combustion engine and supplies some other driving force from the internal combustion engine.

[0042]

As described above, according to the first aspect of the invention, the driving means, the high-voltage driving power source, the low-voltage controlling power source, the input / output control means, the state detecting sensor, the abnormal state detecting means, the power shut-off means. Since the power cutoff means cuts off only the driving power supply in accordance with the abnormality detected by the abnormality detection means, it is impossible to drive other electric components such as headlights due to the abnormality of the driving power supply system. Is prevented. According to the third aspect of the present invention, the driving means, the high-voltage driving power supply, the low-voltage controlling power supply, the input / output control means, the state detection sensor, the abnormal state detection means, and the power cutoff means are provided, and the abnormal state detection means is used for the vehicle When an abnormality is detected, the power cut-off means instructs the input / output control means to stop the current input / output and cuts off only the drive power supply, so that the drive power supply can be easily cut off. Therefore, it is possible to prevent the other electric components from being unable to be driven due to an abnormality of the driving power supply system or the like.

[Brief description of drawings]

FIG. 1 is an arrangement configuration diagram showing an arrangement state of each part of a power cutoff device for an electric vehicle according to an embodiment of the present invention.

FIG. 2 is an external configuration diagram of the roller mite type collision sensor.

FIG. 3 is a configuration diagram showing a circuit configuration of a control unit and states around the same.

FIG. 4 is a circuit configuration diagram of the diagnostic device in the control unit.

FIG. 5 is a circuit configuration diagram of the interruption device in the control unit.

FIG. 6 is a configuration diagram showing a circuit configuration of a control unit and a peripheral state thereof in a second embodiment of the present invention.

FIG. 7 is a flowchart showing the operation of the second embodiment.

FIG. 8 is a configuration diagram showing a circuit configuration of a control unit and a peripheral state thereof in a third embodiment.

FIG. 9 is a flowchart showing the operation of the third embodiment.

[Explanation of symbols]

 12 Drive Wheel 13 Electric Motor 14 Main Power Supply 15 Control Unit 17 Power Supply for Auxiliary Machine 18 Collision Sensor 21, 64, 71 Diagnostic Device 22 Power Cutoff Signal 23 Breaking Device 24 Driver 25 Controller 27 Motor Current 61 Airbag 62 Emergency Brake 63 Distance Measurement Sensor 73 Abnormality detection signal

Claims (5)

[Claims] 1. A drive means for electrically generating at least a part of a driving force of a vehicle, a high-voltage drive power supply for supplying power to the drive means, and a control power supply for supplying low-voltage power, A control power source is used as a power source, an input / output control unit that controls input / output of current between the drive power source and the drive unit, a state detection sensor that detects a state of a vehicle, and the control power source as a power source, An abnormal state detecting means for detecting an abnormal state of the vehicle from the output value of the state detecting sensor and the control power source as a power source, and when the abnormal state of the vehicle is detected by the abnormal state detecting means, the driving power source is used. A power shutoff device for an electric vehicle, comprising: a power shutoff means for shutting off only the power source. 2. The abnormal state detected by the abnormality detecting means is a vehicle collision, an abnormal approach, a leakage of a driving power source, or a short circuit of a driving circuit including the driving power source.
A power cutoff device for the electric vehicle described. 3. A drive means for electrically generating at least a part of a driving force of a vehicle, a high-voltage drive power supply for supplying power to the drive means, and a control power supply for supplying low-voltage power. A control power source is used as a power source, an input / output control unit that controls input / output of current between the drive power source and the drive unit, a state detection sensor that detects a state of a vehicle, and the control power source as a power source, The abnormal state detection means for detecting an abnormal state of the vehicle from the output value of the state detection sensor, and the control power source as a power source, and when the abnormal state of the vehicle is detected by the abnormal state detection means, the input / output control is performed. A power cutoff device for an electric vehicle, comprising: a power cutoff unit that cuts off only the driving power source while instructing the unit to stop inputting and outputting current. 4. The power cutoff means instructs the input / output control means to stop the input / output of current when the abnormal state detection means detects an abnormal state of the vehicle, and the current value is changed. 4. The power cut-off device for an electric vehicle according to claim 3, wherein the driving power supply is cut off after the driving power becomes equal to or less than a predetermined value. 5. The power cutoff means instructs the input / output control means to stop the input / output of current when the abnormal state detection means detects an abnormal state of the vehicle, and a predetermined amount is issued from the instruction. The power cutoff device for an electric vehicle according to claim 3, wherein the driving power supply is cut off after a lapse of time.