JP2000102111A - Regeneration controlling unit for hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To determine the optimum regeneration capacity that matches the deceleration state of a vehicle and the charging state of an accumulating device while bringing out the power generating efficiency of a motor sufficiently, by correcting the regeneration power at a rate in accordance with the difference between the regeneration capacity and the overcharged capacity. SOLUTION: In a regeneration controlling unit ECU 7, the sum is obtained of the actually detected capacity of a capacitor of an accumulating device 5 and decelerating regeneration capacity. Then, preset maximum permissible charging capacity is deducted from the sum to calculate the overcharged capacity. A correcting coefficient is obtained from the rate calculated by dividing the difference between the decelerating regeneration capacity and overcharged capacity by the decelerating regeneration capacity. The regeneration capacity is corrected by multiplying it by the correcting coefficient. This constitution enables the regeneration to be controlled in such a way that the accumulating device 5 does not exceed the maximum permissible charging capacity via a power drive unit 4 under the control of a motor controlling unit ECU 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative control device at the time of deceleration in a hybrid vehicle powered by an engine and an auxiliary motor for the engine.

[0002]

2. Description of the Related Art Conventionally, in a hybrid vehicle using an engine and an auxiliary motor for the engine as power sources,
By operating the motor as a generator at the time of deceleration, using a table in which the regenerative amount according to the operating state of the vehicle such as vehicle speed and engine negative pressure is set in advance, a predetermined value corresponding to the operating state of the vehicle at that time is used. The regenerative amount is determined, and when a deceleration determination condition such as when the throttle is fully closed or the brake is depressed during driving is satisfied, a predetermined amount of regenerative power is stored by a battery or capacitor as a power source for motor drive. I try to charge the device.

[0003]

The problem to be solved is that if the power storage device is charged with a regenerative amount that is uniformly determined according to the driving state of the vehicle at the time of deceleration, there is an opportunity for deceleration. In many cases, the power storage device easily falls into an overcharged state. At this time, overcharging is a problem particularly when a capacitor composed of an electric double layer capacitor having a relatively small capacity is used for the power storage device, and there is a possibility that the characteristics may be deteriorated or destroyed due to the overcharging.

Further, if the decelerating and regenerating drive of the motor is stopped when the power storage device is fully charged, the feeling of deceleration due to the regenerative braking is suddenly lost. There is.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a power storage device is provided so that an optimum regenerative amount can be determined in accordance with a deceleration state of a vehicle and a state of charge of a power storage device while sufficiently extracting the power generation efficiency of a motor. A current charging amount of the power storage device is detected, and a preset allowable charging amount of the power storage device is subtracted from a sum of the detected charging amount of the power storage device and a regenerative amount determined according to a driving state of the vehicle. The amount of overcharge is calculated by using the calculated amount of overcharge, and the amount of regeneration is corrected at a rate corresponding to the difference between the amount of regeneration and the calculated amount of overcharge.

Further, the present invention provides a power storage device capable of performing optimal deceleration regeneration control to prevent the power storage device from being overcharged without losing regenerative braking. When the total amount of the detected charge amount of the power storage device and the regenerative amount determined according to the driving state of the vehicle is larger than the allowable charge amount of the power storage device that is estimated in advance. The regeneration amount is set to 0 and regeneration is prohibited.

[0007]

FIG. 1 shows a system configuration of a hybrid vehicle, comprising an engine 1, a motor 2 for assisting an engine, a transmission 3, a power drive unit 4 for driving a motor, and a power storage device 5 as a power supply for driving the motor. The drive system includes a drive system, and a control system including a motor ECU 6 that controls the drive and regeneration of the motor 2 via the power drive unit 4 and an ECU 7 that performs overall control. Power storage device 5 includes a battery or a capacitor. In the figure, reference numeral 8 denotes driving wheels of the vehicle.

[0008] The ECU 7 reads detection signals from various sensors to determine the driving state of the vehicle, and according to the driving state of the vehicle at that time, starts, idle-stop mode, idle mode, acceleration assist mode, and cruise. Mode and the deceleration regeneration mode are determined, and an instruction to execute the determined operation mode is given to the motor ECU 6. Then, the motor ECU 6 to which the execution command of the operation mode is given is configured to appropriately control the stop of the motor 2, the assist drive, and the deceleration regeneration via the power drive unit 4.

Here, by controlling the downverter 9 by the ECU 7, the voltage of the power storage device 5 is reduced to a predetermined value to charge the battery 10 for the 12V power supply. In the figure, reference numeral 11 denotes a 12V power supply load.

FIG. 2 shows a flow of processing in the ECU 7 for setting the operation mode of the motor 2 according to the driving state of the vehicle.

Here, first, after checking whether or not the starter switch is on (step S1), if it is on, the engine speed Ne detected by the sensor at that time is determined in advance. It is determined whether or not the rotation speed is equal to or less than the rotation speed NCR set for the engine stop determination (step S2). At that time, Ne ≦ NCR
If so, the start mode is set (step S3).

If the starter switch has not been turned on at the time of the determination in step S1, the engine stop control execution flag F / FCMG for controlling whether or not to stop the engine during idling is set to 1. Is checked (step S4), the flag FF
If the CMG does not stand, the process proceeds to the determination in step S2.

At this time, the engine stop control execution flag F
-If FCMG stands at 1, the throttle opening TH detected by the sensor is the idle opening (fully closed) THID
It is determined whether or not LE has been set (step S
5).

When determining in step S5, TH ≦ THIDL
If E, then it is determined whether or not the vehicle speed V is 0 (step S6). If V = 0 at that time, it is determined whether or not the engine stop control execution flag F · FCMG is set to 1 (step S7).
If the FCMG is set, the idle mode is set (step S8). If the flag F.FCMG is not set, the idle mode is set (step S9).

If V = 0 is not set in the determination at step S6, the engine stop control execution flag F / FCMG
Is set to 1 (step S10), and if the flag F.FCMG is set, the deceleration regeneration mode is set (step S12). In addition, the flag FF
If the CMG is not standing, it is determined whether or not the idling control execution flag F · IDLE for instructing the engine to idle is standing at 1 (step S11). At that time, if the flag F.IDLE is set, the idle mode is set (step S9), and the flag F.IDLE is set.
If LE is not set, the deceleration regeneration mode is set (step S12).

At the time of determination in step S5, TH ≦ TH
If it is not IDLE, a preset assist trigger table is searched to determine whether the vehicle is in an acceleration state or a cruise state (step S13).

FIG. 3 shows the contents of the assist trigger table which is set for each gear position. The engine trigger speed Ne and the throttle opening TH are used as parameters.
When the throttle opening TH tends to increase as the engine speed Ne decreases, the acceleration mode determination flag F · MAST changes from 0 to 1 when the throttle opening TH becomes equal to or higher than the high MASTH line, and the engine speed is increased. If the throttle opening TH tends to decrease as the number Ne increases, the lower MAST is set.
When the speed is below the L line, the acceleration mode determination flag FM
AST changes from 1 to 0.

Then, the acceleration mode determination flag F.MAS
Check whether T stands at 1 (step S14),
If the flag F.MAST is set, the acceleration mode is set (step S15), and the flag F.MAST is set.
If is not set, the cruise mode is set (step S16).

When each operation mode of the motor 2 is set as described above, the ECU 7 outputs an execution command of each operation mode to the motor ECU 6 (step S17), and the same processing is repeated.

According to the present invention, when the regenerative mode is set under the control of the ECU 7, sensor signals of the engine speed and the engine negative pressure are read and the transmission 3
, The regenerative amount according to the driving state of the vehicle at that time is determined, and the determined regenerative amount is corrected in accordance with the state of charge of the power storage device 5. .

As the shift state of the transmission 3, if the transmission 3 is a stepped (MT), the gear shift position is detected, and if the transmission 3 is a stepless (CVT), the gear ratio is detected. .

FIG. 4 shows a flow of processing when the ECU 7 determines the regenerative amount according to the driving state of the vehicle and corrects the determined regenerative amount.

First, in the case of MT, it is determined whether or not the clutch switch is off (step S2).
1) If the clutch switch is off, then
When the gear shift position switch is in the neutral position (C
In the case of VT, it is determined whether the vehicle is in the neutral N or parking P position (step S22).

At that time, if it is not in the neutral position,
It is determined whether or not the brake switch is off (step S23). If the brake switch is off,
The regenerative amount map in the brake-off mode registered in advance in the internal memory of the ECU 7 is searched to determine the regenerative amount according to the driving state of the vehicle at that time (step S2).
4).

If the brake switch is on at the time of the determination in step S23, the ECU
The regenerative amount map according to the driving state of the vehicle at that time is determined by searching a regenerative amount map in the brake-on mode registered in the internal memory 7 (step S25).

The regeneration amount in the brake-on mode is as follows.
This is set in consideration of an increase in the regenerative amount when decelerating by depressing the brake.

When the clutch switch is on at the time of the determination at step S21, or when the gear shift position switch is at the neutral position at the time of the determination at step S22, the regenerative amount REGEN.
Is set to 0 (step S26).

When the regeneration amount is determined in this way, a regeneration amount correction process (see FIG. 5) according to the state of charge of the power storage device 5 at that time is executed (step S2).
7).

The above processing is repeatedly performed at a predetermined sampling cycle (about 10 ms).

Table 1 shows an example of a regenerative amount map at the time of brake off which is set for each gear position of the MT using the rotational speed and negative pressure of the engine 1 as parameters.

Here, the engine speed is divided into levels NEREG0 to NEREG19 of n = 20,
Reduce the engine negative pressure to the level PBREG0-PBR of n = 11.
EG10. For example, when the detected engine speed is at the level of NEREG1 and the engine load is PBR
When the level is EG1, the regeneration amount is REGEN #
It is determined as n11.

[0032]

[Table 1]

Table 2 shows the engine speed NEREGBR and the engine negative pressure PBREGB when the brake is on.
An example of a regeneration amount map at the time of brake-on set for each gear position of the MT using R as a parameter is shown.

[0034]

[Table 2]

In the relationship shown in Tables 1 and 2, the regenerative amount increases as the engine speed increases and the engine negative pressure increases.

Similarly, in the case of the CVT, similarly, a regeneration amount map in which the engine speed and the vehicle speed in the brake-off mode and the brake-on mode are set as parameters is prepared.

FIG. 5 shows a flow of the regeneration amount correction processing.

Here, first, a QREGEN table in which the characteristics of the deceleration regeneration amount are set in advance in accordance with the vehicle speed is searched, and the deceleration regeneration amount QREGEN that is predictively obtained according to the vehicle speed at that time is obtained (step S30). S31).

FIG. 6 shows characteristics of the deceleration regeneration amount QREGEN with respect to the vehicle speed VREG set in the QREGEN table. The predicted value of the deceleration regeneration amount obtained according to the vehicle speed is defined assuming that the capacitor capacity of the power storage device 5 is 100%. It is set as a value represented by the ratio of the case.

Then, the total QTOTAL of the actually detected capacitor capacity QCAP of the power storage device 5 and the deceleration regeneration amount QREGEN predicted from the table is obtained (step S32), and the total QTOTAL is set in advance based on the total QTOTAL. The overcharge amount QOVER is calculated by subtracting the maximum allowable charge amount QCAPLMTH (step S33).

Next, the deceleration regeneration amount QR predictedly obtained
It is determined whether or not EGEN is lower than a predetermined regeneration lower limit value QREGLMTL (step S34). If it is lower, the deceleration regeneration amount QREGEN and the overcharge amount VOV are determined.
A correction coefficient α is obtained from a ratio obtained by dividing the difference from ER by the deceleration regeneration amount QREGEN (step S35).

Then, the regenerative amount REGEN at the time of brake-off determined by previously searching the regenerative amount map.
Is multiplied by the obtained correction coefficient α to perform the regeneration amount correction (step S36).

Alternatively, the regenerative amount REGEN at the time of brake-on determined by previously searching the regenerative amount map.
The regeneration amount is corrected by multiplying BR by the obtained correction coefficient α (step S37).

When the predictive deceleration regeneration amount QREGEN is equal to or smaller than the predetermined regeneration lower limit value QREGLMTL at the time of the determination in step S34, the correction coefficient α is set to 0.
To prevent the regeneration amount correction from being performed (step S38).

When the regenerative amount is corrected in this way, the corrected data of the regenerative amount is given from the ECU 7 to the motor ECU 6, whereby the electric power is stored in the power storage device 5 via the power drive unit 4 under the control of the motor ECU 6. Regenerative control is performed so as not to exceed the maximum allowable charge amount.

FIG. 7 shows the state of the capacitor capacitance CAP of the power storage device 5 before (A) and after (B) the correction of the regeneration amount.

As described above, according to the present invention, by correcting the amount of regenerative power, the power storage device 5 is provided with an optimum regenerative amount corresponding to the vehicle deceleration state and the state of charge of the power storage device 5.
Can be performed so as not to always exceed the maximum allowable charge amount. Therefore,
Since the decelerating and regenerating drive of the motor 3 remains unchanged, regenerative braking of the motor 2 is not lost, and a constant deceleration feeling is always obtained. Then, the free capacity of the power storage device 5 can be constantly regenerated, and the regenerative energy from the motor 2 can be effectively used.

As another embodiment of the present invention, E
When the regenerative mode is set under the control of the CU 7, the sum of the regenerative amount determined according to the driving state of the vehicle by the regenerative amount map search and the currently detected charged amount of the power storage device 5 is the power storage device. Is larger than the preset maximum allowable charge amount, the regenerative amount is set to 0 and the power storage device 5
We take measures to prohibit regeneration to the public.

FIG. 8 shows a flow of processing when the ECU 7 sets the regeneration amount according to the driving state of the vehicle to 0 and prohibits regeneration to the power storage device 5.

In this processing flow, instead of the regeneration amount correction processing in step S26 in the flow shown in FIG. 4,
A regeneration prohibition process is performed (step S4).
7). The contents of steps S41 to S46 are the same as steps S21 to S26 in the flow of FIG.

FIG. 9 shows a flow of the regeneration prohibition processing.

Here, first, the QREGEN table is searched to determine the deceleration regeneration amount QREGEN that is predictively obtained according to the vehicle speed at that time (step S5).
1) The total QT of the deceleration regeneration amount QREGEN and the actually detected capacitor capacitance QCAP in the power storage device 5
OTAL is calculated (step S52).

Then, the calculated sum QTOTAL
Is the maximum allowable charge amount QCAPL of power storage device 5 set in advance.
It is determined whether it is smaller than MTH (step S5).
3).

At that time, QTOTAL> QCAPLMT
If it is H, the regeneration amount REGENBR at the time of brake-off or the regeneration amount REGENBR at the time of brake-on determined by searching the regeneration amount map earlier is set to 0 (step S54), and regeneration to the power storage device 5 is prohibited. I do.

If the power storage device 5 has a margin at that time and QTOTAL ≦ QCAPLMTH, the regeneration amount REGEN when the brake is off or the regeneration amount REGE when the brake is on is determined without inhibiting regeneration.
Regeneration to power storage device 5 is performed with NBR.

As described above, according to the present invention, by performing the regeneration prohibition process, the power storage device 5 may be overcharged without stopping the drive of the motor 3 for deceleration regeneration. Regeneration can be prevented beforehand. Further, the regenerative braking of the motor 2 is not lost, and a constant deceleration feeling can be always obtained.

[0057]

As described above, in the regeneration control device for a hybrid vehicle according to the present invention, the current charge amount of the power storage device is detected, and the current charge amount of the power storage device is determined in accordance with the detected charge amount of the power storage device and the driving state of the vehicle. An overcharge amount is calculated by subtracting a preset allowable charge amount of the power storage device from the sum of the determined regenerative amount and the regenerative amount at a rate corresponding to a difference between the regenerative amount and the calculated overcharge amount. Since the amount is corrected, there is an advantage that it is possible to determine an optimum regeneration amount that matches the deceleration state of the vehicle and the state of charge of the power storage device while sufficiently extracting the power generation efficiency of the motor. .

In the regeneration control device for a hybrid vehicle according to the present invention, the current charge amount of the power storage device is detected, and the current charge amount of the power storage device is determined according to the detected charge amount of the power storage device and the driving state of the vehicle. The regenerative amount is set to 0 and regenerative is prohibited when the sum of the regenerative amount and the regenerative amount is larger than the estimated allowable charge amount of the power storage device in advance, so that the power storage device is overcharged without loss of regenerative braking. There is an advantage that optimal deceleration regeneration control can be performed so that the state can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a system configuration of a hybrid vehicle according to the present invention.

FIG. 2 is a diagram illustrating a flow of a process for setting a motor operation mode according to a driving state of a vehicle.

FIG. 3 is a characteristic diagram showing contents of an assist trigger table set for each gear position.

FIG. 4 is a diagram illustrating a flow of a process of determining a regenerative amount according to a driving state of a vehicle and correcting the determined regenerative amount.

FIG. 5 is a diagram showing a flow of a regeneration amount correction process.

FIG. 6 shows a vehicle speed VRE set in a QREGEN table.
It is a figure which shows the characteristic of the deceleration regeneration amount QREGEN with respect to G.

FIGS. 7A and 7B are graphs respectively showing states of a capacitor capacity of a power storage device before and after a regeneration amount is corrected.

FIG. 8 is a diagram showing a flow of processing when the regeneration amount according to the driving state of the vehicle is set to 0 and regeneration to the power storage device is prohibited.

FIG. 9 is a diagram illustrating a flow of a regeneration prohibition process.

[Description of Signs] 1 engine 2 motor for engine assist 3 transmission 4 power drive unit 5 power storage device 6 motor ECU 7 ECU 9 downverter 10 battery for 12V power supply

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoichi Iwata 1-4-1 Chuo, Wako, Saitama Prefecture Inside Honda R & D Co., Ltd. (72) Yoshitaka Kuroda 1-4-1 Chuo, Wako, Saitama Inside Honda R & D Co., Ltd. (72) Keisuke Uchida, Inventor Keisuke Uchida 1-4-1, Chuo, Wako-shi, Saitama Prefecture Inside Honda R & D Co., Ltd. F-term (reference) in PSG 5H115 PA08 PG04 PI15 PI16 PO17 PU01 PU22 QE10 QI04 QN03 RB08 TB01 TE03 TI01 TU16

Claims (2)

[Claims] 1. A motor that operates as a generator during deceleration of an engine and a hybrid vehicle that uses an auxiliary motor for the engine as a power source, and generates a motor having a regenerative amount determined according to a driving state of the vehicle at that time. In a regenerative control device for a hybrid vehicle that charges a power storage device for driving, a means for detecting a charge amount of the power storage device, and a sum of the detected charge amount of the power storage device and the regeneration amount, the power storage device A means for calculating an overcharge amount by subtracting a preset allowable charge amount and a means for correcting the regenerative amount at a rate corresponding to a difference between the regenerative amount and the calculated overcharge amount are provided. The regeneration control device for a hybrid vehicle according to claim 1, wherein: 2. A motor that operates as a generator during deceleration of a hybrid vehicle that uses an engine and an auxiliary motor for the engine as a power source, and uses a regenerative amount determined according to the operating state of the vehicle at that time. In a regenerative control device for a hybrid vehicle that charges a power storage device for driving, a means for detecting a charge amount of the power storage device, and a sum of the detected charge amount of the power storage device and the regeneration amount is determined in advance by the power storage device. A regenerative control device for a hybrid vehicle, wherein a regenerative amount is set to 0 and regenerative prohibition is performed when the amount is larger than a set allowable charge amount.