JP2007210415A - Hybrid controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for stopping a vehicle to prevent the vehicle from shifting down on a descending road, when one inverter is drive-prohibited. <P>SOLUTION: This hybrid controller is provided with an inverter circuit condition acquiring means for acquiring respective conditions of two inverter circuits, an inverter circuit determination means for judging whether the both of the two inverter circuits are drive-prohibited or not, based on the conditions of the inverter circuits acquired by the inverter circuit condition acquiring means, a vehicle travel condition acquiring means, a vehicle travel condition determination means for judging whether the shifting-down of the vehicle occurs or not by the drive prohibition of the both of the two inverter circuits, in the vehicle travel condition acquired by the vehicle travel condition acquiring means, and a vehicle braking means for braking the vehicle, based on a result in the vehicle travel condition determination means. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hybrid control device for a hybrid vehicle.

  The hybrid system for vehicles refers to a vehicle that travels by combining two types of power sources, that is, an engine and an electric motor. This hybrid system for vehicles uses a series hybrid system in which a generator is driven by an engine, and a motor drives wheels by the generated power, and a method in which the engine and motor drive wheels, and two driving forces are applied depending on the situation. There are parallel hybrids that can be used in series and series / parallel hybrids that combine the features of both. The series / parallel hybrid divides the engine power by the power split mechanism, and directly drives the wheels on the one hand, and the other uses it for power generation to control the usage rate according to the running state and drive the motor with the generated power. The motor usage rate is higher than that of the parallel system. A motor generator having both functions is used for the generator and the motor. However, in the following explanation, the first motor generator (generator) is mainly used for the function of the generator, and the function of the motor is mainly used. What is played is represented as a second motor generator (motor).

  As shown in FIG. 3, the hybrid drive device 1 used in such a series / parallel hybrid system includes a power split mechanism 20, a first motor generator 16 (generator), a second motor generator 22 (motor), and It consists of reduction gears 30, 32, etc. The power from the engine is divided into two by the power split mechanism 20, one of its output shafts is connected to the second motor generator 22 (motor) and wheels, and the other is connected to the first motor generator 16 (generator). The power of is transmitted to the wheel by two paths, mechanical and electrical. Since the rotation speed of the engine 12 and the rotation speeds of the first motor generator 16 (generator) and the second motor generator 22 (motor) (proportional to the vehicle speed) can be increased and decreased steplessly, A transmission such as a gasoline engine car is not provided (see, for example, Patent Document 1).

  The power split mechanism 20 is constituted by a planetary gear (planetary gear), and splits the torque of the engine 12 into the output shaft 19 and the first motor generator 16 (generator) at the ratio of each constituent gear. . The rotating shaft of the carrier 20c inside the gear mechanism is connected to the engine 12 via a damper device 14 that absorbs rotational fluctuations, and transmits power to the outer ring gear 20r and the inner sun gear 20s through the pinion gear. The sun gear rotating shaft 24 is connected to the first motor generator 16 (generator), and the rotating shaft 18 of the ring gear 20 r is directly connected to the second motor generator 22 (motor) and the output shaft 19. Thus, the rotation of the ring gear 22r by the second motor generator 22 (motor) directly drives the wheel.

  The rotational speed of the engine 12 (the rotational speed of the carrier 20c), the rotational speed of the second motor generator 22 (motor) (the rotational speed of the ring gear 20r), and the rotational speed (the sun gear) of the first motor generator 16 (generator) in the planetary gear device. The relationship of the number of rotations of 20 s) is expressed by a nomograph. As shown in FIG. 4, the alignment chart shows the number of rotations on the vertical axis and the distance on the horizontal axis according to the gear ratio of each gear. On the nomograph, the rotational speeds of the gears are always connected by a straight line. For this reason, the rotation speed of the ring gear 20r (second motor generator (motor) direct connection shaft) that transmits the driving force to the wheels and the rotation speed of the sun gear 20s (first motor generator (generator) direct connection shaft) are the carrier 20c (engine direct connection shaft). When the rotation speed of the ring gear 20r (second motor generator (motor) direct connection shaft) increases, the sun gear 20s (first motor generator (generator) direct connection shaft) rotates. The number decreases, and when the rotation speed of the ring gear 20r (second motor generator (motor) direct connection shaft) decreases, the rotation speed of the sun gear 20s (first motor generator (generator) direct connection shaft) increases. The increase / decrease relationship of the rotation speed of the ring gear 20r (second motor generator (motor) direct connection shaft) and the sun gear 20s (first motor generator (generator) direct connection shaft) is established regardless of the rotation of the carrier 20c (engine direct connection shaft). .

  On the other hand, in order to drive the motor generator by the power storage device or to charge the power storage device by the motor generator, the hybrid vehicle is provided with a power supply device as shown in FIG. The power supply device includes inverter circuits 36 and 37, a power storage device 40, a DC / DC converter 39, and capacitors 35 and 38 for driving the first motor generator 16 (generator) and the second motor generator 22 (motor). Have. The two inverter circuits are connected to each other by two connection lines, and a capacitor 35 is provided between the two connection lines. A DC / DC converter 39 is connected to these two connection lines, and a capacitor 38 and a power storage device 40 are connected to the DC / DC converter 39 in parallel.

  In the power supply device having such a configuration, when the inverter circuit 37 of the second motor generator 22 (motor) is abnormally stopped for some reason, if the drive of the inverter circuit 36 of the first motor generator 16 (generator) is continued, Since the power generation operation in the first motor generator 16 (generator) is continued, the DC power is rapidly accumulated in the capacitor 35, and the voltage Vm across the capacitor 35 rapidly increases. In this case, if a current flows through the inverter circuit 36, the switching loss in the inverter circuit 36 increases and the life of the inverter circuit 36 decreases. Therefore, the inverter circuit 36 is forcibly stopped by an abnormal stop of the inverter circuit 37 in order to prevent the voltage Vm across the capacitor 35 from increasing and reducing the life of the inverter circuit 36.

  On the other hand, if the inverter circuit 36 is abnormally stopped, the second motor generator 22 (motor) accumulates in the capacitor 35 even if power is not supplied from the first motor generator 16 (generator) to the capacitor 35. When the inverter circuit 37 is not stopped because the consumed power is consumed, the voltage Vm across the capacitor 35 rapidly decreases, and a large current flows toward the power storage device 40 via the diode of the DC / DC converter 39. Flows to the side. Then, the fuse is blown or the life of the DC / DC converter 39 is reduced due to the influence of a large current. Therefore, the inverter circuit 37 is forcibly stopped by the abnormal stop of the inverter circuit 36 in order to blow the fuse due to the decrease in the voltage Vm across the capacitor 35 or to protect the DC / DC converter 39.

  As described above, when one inverter circuit is in a drive prohibited state for some reason, the other inverter circuit is also in a drive prohibited state in order to prevent overvoltage, and the inverter circuit is in a drive prohibited state. And no function at all (for example, see Patent Document 2).

JP-A-9-170533 JP 2004-112883 A

  In the series / parallel hybrid system vehicle including the hybrid drive unit 1 including the power split mechanism 20, the first motor generator 16 (generator), the second motor generator 22 (motor), the reduction gears 30 and 32, and the like. If the both-side drive prohibition state of the inverter circuit occurs during steady running, the torque of the second motor generator 22 (motor) directly connected to the ring gear 20r directly driving the wheels disappears, and the running resistance of the ring gear 20r Although the rotational speed and the vehicle speed decrease, the first motor generator 16 (generator) does not operate by prohibiting the drive of both inverters, and thus the rotational speed and speed of the ring gear 20r cannot be prevented. The vehicle will stop.

  When the vehicle is traveling on a hill, after stopping, the vehicle moves backward due to gravity and tries to reversely rotate the ring gear 20r (second motor generator (motor) direct connection shaft). As described above, the reverse rotation of the ring gear 20r can be prevented if the first motor generator 16 (generator) directly connected to the sun gear 20s can be rotated, but the inverter circuits 36 and 37 are both driven. When it is prohibited, the first motor generator 16 (generator) cannot be rotated. Further, unlike the conventional vehicle, since there is no transmission between the engine 12 and the wheel 58, the reverse rotation of the wheel cannot be stopped by the engine 12. For this reason, when one of the inverters is in a drive-inhibited state, both inverters are in a drive-inhibited state, and the vehicle slips down on the slope.

  Therefore, an object of the present invention is to provide means for stopping a vehicle in order to prevent the vehicle from sliding down on a slope when one inverter is prohibited from being driven.

  An object of the present invention is to control a power distribution mechanism that distributes power between an engine and two motor generators, two inverter circuits provided corresponding to the two motor generators, and two inverter circuits, respectively. An inverter control circuit for controlling the travel of a hybrid vehicle, comprising: an inverter circuit state acquisition means for acquiring a state of each inverter circuit; and an inverter circuit acquired by the inverter circuit state acquisition means. In the vehicle traveling state acquired by the inverter circuit determining means for determining whether or not both of the two inverter circuits are prohibited based on the state, the vehicle traveling state acquisition means, and the vehicle traveling state acquisition means, Both of the two inverter circuits were prohibited from driving A vehicle traveling state determining means for determining whether the sliding down of the vehicle occurs that can be solved by a vehicle braking means the braking of the vehicle based on the result of the vehicle running state judging means.

  In the present invention, the vehicle travel state determination means may be a means for comparing the absolute value of the vehicle speed acquired by the vehicle travel state acquisition means with a predetermined value, or the vehicle acceleration acquired by the vehicle travel state acquisition means A means for comparing with a predetermined value may be used. Further, the vehicle stop means may increase the master cylinder pressure command value of the hydraulic brake to decelerate and stop the vehicle.

  The hybrid control device according to the present invention has an effect of preventing the vehicle from sliding down on a slope even when one of the inverters is prohibited from being driven.

  Hereinafter, an embodiment according to the present invention will be described in detail with reference to FIGS. FIG. 1 shows the configuration of the present invention. The hybrid drive device 1 similar to that described in the background art includes an engine 12, a power split mechanism 20, a first motor generator 16 (generator), a second motor generator 22 (motor), reduction gears 30, 32, and the like. . A driving inverter circuit 36 is connected to the first motor generator 16 (generator). Similarly, a driving inverter circuit 37 is connected to the second motor generator 22 (motor). These two inverter circuits are connected to each other by two electric wires, and a capacitor 35 is provided in the middle of the connection line, and DC power is supplied to the two connection lines from the power storage device 40 via the DC / DC converter 39. Has been.

  The inverter circuits 36 and 37 are controlled by the inverter control circuit 11 so that the rotation speed and torque of each motor generator become command values from the hybrid control device 10. Each of the inverter circuits 36 and 37 outputs a signal indicating whether the circuit state is normal to the inverter control circuit 11. When an abnormality occurs in each of the inverter circuits 36 and 37, the inverter control circuit 11 outputs a drive prohibition command to each of the inverter circuits 36 and 37 and stops each inverter circuit.

  The inverter control circuit 11 receives a control command value signal such as the number of revolutions and torque for controlling each inverter from the hybrid control device 10, and the inverter control circuit indicates whether each inverter circuit is in a normal state or an abnormal state. A signal is output to the hybrid control device 10.

  On the other hand, the output of the hybrid drive device 1 is transmitted to the differential device 34 through the reduction gears 26, 30, and 32, and is transmitted to the wheels 58 through the axle 33 connected to the differential device 34, thereby driving the vehicle. . The wheel 58 is provided with a brake device 57 including a brake pad and a brake disk for stopping the rotation. The brake device 57 is connected to a master cylinder 52 for driving the device, and presses a brake pad against a brake disk by the hydraulic pressure of the master cylinder 52 to brake the wheels, thereby decelerating and stopping the vehicle. The drive hydraulic pressure of the master cylinder 52 is controlled by the hydraulic control device 50, and a hydraulic pressure command signal is input to the hydraulic control device 50 from the hybrid control device. Further, the vehicle is provided with a speed detector 54 that measures the vehicle speed from the number of rotations of the wheel, and a signal from the speed detector 54 is input to the hybrid control device 10.

  The hybrid control device 10 acquires an inverter circuit state acquisition unit 101 that acquires a status signal of each inverter circuit from the inverter control circuit 11, an inverter circuit determination unit 102 that determines whether the inverter circuit is in a drive-inhibited state, and a traveling state of the vehicle. A vehicle running state obtaining unit 103, a vehicle running state judging unit 104 for judging the running state of the vehicle, and a vehicle braking unit 105 for outputting a braking command for the vehicle are provided.

Next, the operation of the hybrid control apparatus of the present invention will be described with reference to FIGS.
(1) When the hybrid vehicle is running normally, the inverter circuits 36 and 37 operate normally and no abnormal signal is output.
(2) When one of the inverter circuits 36 and 37 fails for some reason, an abnormal signal is output from the failed inverter circuit to the inverter control circuit 11.
(3) The inverter control circuit 11 outputs an inverter drive prohibition command to the inverter that has transmitted the abnormal signal, stops the operation of the failed inverter, and sends a signal indicating that one inverter has become a drive prohibition command to the hybrid controller 10. Output. This signal is acquired by the hybrid control device 10 by the inverter circuit state acquisition means 101 of the hybrid control device 10 (FIG. 2, step S11).
(4) The inverter control circuit 11 also outputs an inverter drive prohibition command to the other inverter that has not failed, and stops the operation of the inverter that has not failed.
(5) When the inverter circuit that has not failed is stopped, the inverter circuit outputs an inverter drive inhibition state signal to the inverter control circuit 11. The inverter control circuit 11 outputs to the hybrid control device 10 a signal for which another one of the inverters has become a drive prohibition command, and this signal is acquired by the hybrid control device 10 by the inverter circuit state acquisition means 101 of the hybrid control device 10. (FIG. 2, step S11).
(6) Based on the signal acquired by the inverter circuit state acquisition unit 101, the hybrid control device 10 determines whether both inverters are in a drive prohibited state by the inverter circuit determination unit 102. (FIG. 2, step S12).
(7) When both the inverters are not prohibited from driving, an inverter control circuit signal is acquired again (FIG. 2, step S21).
(8) When it is determined that both inverters are in the drive-inhibited state, the hybrid controller 10 uses the vehicle travel state acquisition unit 103 to calculate the absolute value of the vehicle speed based on the signal from the speed detector 54. Is acquired as the running state (FIG. 2, step S13).
(9) The hybrid control device 10 compares the acquired absolute value of the vehicle speed with a predetermined value by the vehicle running state determination means 104, and if the absolute value of the vehicle speed is smaller than the predetermined value, the vehicle slips. When the absolute value of the vehicle speed is larger than a predetermined value, it is determined that the vehicle will not slide down, and the vehicle running state is acquired again. (FIG. 2, steps S14 and S23).
(10) In response to the braking command, the vehicle braking means 105 of the hybrid control device 10 outputs the pressure command value of the master cylinder 52 of the hydraulic brake to the hydraulic control device 50 for vehicle braking.
(11) The hydraulic control device 50 increases the hydraulic master cylinder pressure to the command value, thereby driving the brake device 57 to decelerate and stop the vehicle.

  In the embodiment of the present invention, the vehicle running state determining unit 104 obtains the absolute value of the vehicle speed based on the signal from the speed detector 54 as the running state of the vehicle by the vehicle running state obtaining unit 103. Judgment is made whether or not a descent will occur, and the vehicle is braked. However, when the acceleration becomes negative using an acceleration sensor attached to the vehicle, the descent on the slope is detected and the vehicle is stopped. You may make it do.

  As described above, the hybrid control device according to the present invention has an effect of preventing the vehicle from sliding down on a slope even when one of the inverters is prohibited from driving.

It is a block diagram of embodiment of this invention. It is embodiment flowchart of this invention. It is explanatory drawing of a hybrid drive mechanism apparatus. It is an alignment chart of a hybrid drive device. It is a figure which shows the power supply device of a hybrid vehicle.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Hybrid drive device, 10 Hybrid control device, 11 Inverter control circuit, 12 Engine, 14 Damper device, 16 1st motor generator, 18 Rotating shaft, 19 Output shaft, 20 Power split mechanism, 20c Carrier, 20s Sun gear, 20r Ring gear, 22 Second motor generator, 24 Rotating shaft, 26, 30, 32 Reduction gear, 33 Axle, 34 Differential device, 35, 38 Condenser, 36, 37 Inverter circuit, 39 DC / DC converter, 40 Power storage device, 50 Hydraulic control Device, 52 master cylinder, 54 speed detector, 57 brake device, 58 wheel, 101 inverter circuit state acquisition means, 102 inverter circuit determination means, 103 vehicle running state acquisition means, 104 vehicle running state determination means, 105 vehicle braking means, 10~S23 step, Vm voltage.

Claims (4)

A power distribution mechanism that distributes power between the engine and the two motor generators;
Two inverter circuits provided corresponding to the two motor generators,
An inverter control circuit for controlling each of the two inverter circuits;
A hybrid control device for controlling the traveling of a hybrid vehicle comprising:
Inverter circuit status acquisition means for acquiring the status of each inverter circuit;
Inverter circuit determination means for determining whether or not both of the two inverter circuits are prohibited from driving based on the state of the inverter circuit acquired by the inverter circuit state acquisition means;
Vehicle running state acquisition means;
Vehicle running state determining means for determining whether or not the vehicle slips due to the drive prohibition of both of the two inverter circuits in the vehicle running state acquired by the vehicle running state acquiring unit;
Vehicle braking means for braking the vehicle based on the result of the vehicle running state determination means;
A hybrid control device comprising: The vehicle running state determining means is means for comparing the absolute value of the vehicle speed acquired by the vehicle running state acquiring means with a predetermined value;
The hybrid control device according to claim 1. The vehicle running state determining means is means for comparing the acceleration of the vehicle acquired by the vehicle running state acquiring means with a predetermined value;
The hybrid control device according to claim 1. The vehicle stop means increases the master cylinder pressure command value of the hydraulic brake to decelerate and stop the vehicle,
The hybrid control device according to any one of claims 1 to 3, wherein

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