JP2002354612A - Operation system for hybrid automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an operation system for a hybrid automobile capable of further enhancing effective utilization of energy. SOLUTION: In the hybrid automobile comprising: an engine 2; a generator- driven/motor-driven motor 5 connected to a drive shaft 4 of a wheel; and a battery 6 as a charging device for performing charge and discharge to and from the motor 5, there are provided an information obtaining means for obtaining information on a height along a traveling passage and a pattern determination means for determining a charge and discharge pattern during traveling based on the information on the height. The residual amount of the battery can be recognized for charging the battery before the automobile reaches an upward slope or a downward slope.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid vehicle equipped with an engine and a motor and driving both or one of the wheels and, more particularly, to a hybrid vehicle operation system for further improving the effective use of energy. is there.

[0002]

2. Description of the Related Art In a hybrid vehicle, braking energy during deceleration is recovered (regenerated) and charged in a power storage device such as a battery or a capacitor, and discharged from the power storage device when starting or accelerating to drive a motor. In addition, fuel consumption can be reduced by reducing the load on the engine. At this time, the power storage device cannot be charged any more when it is fully charged, and cannot be discharged any more when it becomes empty. Therefore, in order to prepare for deceleration or starting / acceleration at any time, for example, the remaining charge amount is always 5
It is desirable to keep about 0%.

In a hybrid vehicle, excess energy can be collected and charged to a power storage device when descending a hill, and the motor can be driven by discharging the power storage device when climbing a hill to reduce the load on the engine. That is,
This means that the potential energy due to the height difference is temporarily stored in the power storage device and released.

[0004]

In the actual traveling, the traveling route includes few flat roads and many uphill and downhill roads. On the other hand, deceleration, starting, and acceleration are performed at any time in the traveling route. For this reason, it is inevitable that a driving situation of going downhill after recovering braking energy by deceleration and a driving situation of going uphill after releasing accumulated energy by starting and accelerating appear. If a descending slope is performed after the braking energy is recovered and the remaining charge amount is increased, the potential energy may not be fully recovered. Also,
If the climbing is performed after the remaining energy is reduced by releasing the accumulated energy by starting and accelerating, the engine cannot be backed up, and the fuel consumption may increase.

In order to avoid this, it is necessary to increase the capacity of a power storage device such as a battery and a capacitor, which results in an increase in weight and space.
There is a possibility that fuel consumption will be further increased.

As described above, there is a problem that the effective use of energy is limited in actual running, and the advantages of the hybrid vehicle cannot be fully exhibited.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide an operation system for a hybrid vehicle that further increases the effective use of energy.

[0008]

In order to achieve the above object, the present invention provides an engine, a motor connected to a drive shaft of a wheel and operated by a generator / motor, and charging and discharging between the motor and the motor. A hybrid vehicle having a power storage device for performing the operation, comprising: an information acquisition unit that acquires height information along a traveling route; and a pattern determination unit that determines a charging / discharging pattern during traveling based on the height information. is there.

The pattern determining means determines a charging pattern so that the remaining charge amount of the power storage device increases before reaching the starting point for ascending, and the remaining charge amount of the power storage device decreases at least until reaching the starting point for descending the slope. The discharge pattern may be determined as follows.

[0010] The pattern determining means determines a charging pattern so that the remaining charge amount of the power storage device when the vehicle reaches the uphill starting point is an optimal charging amount for the subsequent ascent. The discharge pattern may be determined so that the remaining charge amount of the device becomes the optimal charge amount for the subsequent downhill.

The pattern determining means determines a charge pattern so that a target charge amount is recovered by a time when a hill starts climbing when the engine is driven with the most economical efficiency, and the vehicle travels only by discharging the power storage device. Sometimes, the discharge pattern may be determined so that the target discharge amount is consumed before the start of the descent.

[0012]

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

First, the principle of the present invention will be described with reference to FIGS. Here, a route bus is taken as an example of a hybrid vehicle. In each of the drawings, the upper part shows a change in the height of the traveling route. The lower part of the figure shows a change in the remaining charge amount of the battery as the power storage device.

The route bus 1 equipped with the operation system for a hybrid vehicle of the present invention is operated such that the remaining charge amount of the battery is maintained at about 50% as in the related art while the vehicle is traveling on a traveling route that continues on a flat road. ing. Therefore, the change in the remaining charge amount of the battery changes around 50%. This route bus
The height information along the traveling route is acquired by the information acquisition means, and the distance from the current position to the starting point for climbing the slope can be sequentially recognized. The time when the route bus reaches the climbing start point is the climbing start time t2. Therefore, before the hill-climbing start time t2 is reached, the remaining charge amount of the battery at the hill-climbing start time t2 is the optimal charge amount (100% in this example, but not necessarily 100%) before the hill-climbing start time t2. At least 50%). The charge pattern is a charge start time t
1 and the slope start time t2 and the optimum charge amount, and shows a scheduled line for charging from the remaining charge amount at the charge start time to the optimum charge amount from the charge start time t to the slope start time t2. The slope of the predetermined line is determined by electric power that can be extracted in excess while consuming running energy from engine output energy obtained when the engine is operated most economically efficiently. If the ascending start time t2 and the optimal charge amount are determined, the charging start time t1 is determined by going back in time with the scheduled line.

The route bus 1 continues to run on the flat road until the charging start time t1 is reached, and the charging start time t
When it becomes 1, charging is started according to the charging pattern, and charging is continued along the scheduled line. That is, the route bus runs while driving the engine most economically efficiently, and collects the surplus excluding the energy consumption due to the running. For example, in the case of a parallel-type hybrid vehicle described later, since the engine is connected to the axle, the torque is increased without changing the engine speed, and the generator is rotated by the increased amount to generate power. In the case of a series hybrid vehicle, it generates more power than is consumed by the motor. As a result, the surplus electric power can be recovered by the battery without affecting running.

The route bus 1 arrives at the start point of the ascent at the start time t2 of the ascent. By this time, the target charge amount has been collected, and the remaining charge amount has reached the optimal charge amount. Then, the route bus 1 starts discharging from the battery at the same time as starting climbing the hill. Since the motor is driven by the discharge from the battery during climbing the hill, the load on the engine is reduced, and the engine can be operated at the point of maximum thermal efficiency. .

After the end of the uphill, charging is performed with a target of about 50% in order to smoothly return to running on a flat road.

In FIG. 1, the change in the remaining charge amount of the battery by the conventional hybrid vehicle is indicated by a two-dot chain line.
In a conventional hybrid vehicle, the remaining charge is maintained at about 50% until the vehicle reaches the starting point of climbing. Therefore, if the engine is backed up after the start of climbing, the remaining charge becomes 0% early. Thereafter, the vehicle must run only with the energy from the engine. However, in the present invention, the remaining charge amount at the starting point of the ascent is the optimal charge amount (100
%), The discharge continues for a long time after the start of climbing. Therefore, the engine can be backed up for a long time. If the optimal charge amount is determined in advance in anticipation of the hill-climbing end time t3 at which the hill-climbing ending point is reached,
The engine can be backed up by continuing the discharge until the climbing is completed.

As described above, the route bus secures the energy required for climbing uphill in advance while allowing the engine to operate at the most economical efficiency, and backs up the engine with the energy on the uphill road. high.

In FIG. 2 as well, the route bus 1 can sequentially recognize the distance from the current position to the starting point of the descent. The point at which the route bus 1 reaches the descent start point is the descent start time t5. Therefore, in the case of the route bus 1, the remaining charge amount of the battery at the descent start time t5 is set to the optimum charge amount (0% in this example, but 0% The discharge pattern is determined so as not to be limited to 50%. The discharge pattern includes a discharge start time t4, a descent start time t5, and an optimum charge amount. From the discharge start time t4 to the descent start time t5, the discharge pattern is from the remaining charge amount at the discharge start time t4 to the optimum charge amount. It shows a scheduled discharge line. The inclination of the predetermined line is determined by a discharge speed when the vehicle travels with driving energy added by discharging from the battery. When the descending slope start time t5 and the optimal charge amount are determined, the discharge start time t4 is determined by going back in time with the scheduled line.

The route bus 1 continues to run on a flat road until the discharge start time t4, and at the discharge start time t4, starts discharging in accordance with the discharge pattern and continues along the scheduled line. While the discharge continues, the load on the engine is reduced.

The route bus 1 reaches the descent start point at the descent start timing t5. By this time, the target charge is consumed and the remaining charge reaches the optimal charge. Then, the route bus 1 starts charging the battery at the same time when the descent starts. Thereby, surplus braking energy at the time of descending slope or energy obtained from the engine is recovered.

After the end of the downhill, discharge is performed with a target of about 50% in order to smoothly return to flat road running.

In the conventional hybrid vehicle, the remaining charge amount is maintained at about 50% until the vehicle reaches the start point of descending slope.
Become. After that, the only way to release the energy is by heat, resulting in waste. However, in the present invention, since the remaining charge amount has decreased to the optimum charge amount (0%) at the descent start point, the charging is continued for a long time after the descent start. Therefore, wasteful release of energy can be avoided for a long time. The load on the engine is reduced during the period from the discharge start time t4 to the descent start time t5. In anticipation of the descent end time t6 to reach the descent end point in advance,
If the optimal charge amount is determined, charging is continued until the descent is completed, and energy consumption due to heat can be suppressed as much as possible.

As described above, the route bus 1 reduces the load on the engine before approaching the downhill road, and secures the recovery capacity of the energy generated during the downhill in advance, so that the energy use efficiency is high.

In FIGS. 1 and 2, charge / discharge is performed according to a scheduled line without deceleration, start, and acceleration during operation of the charge / discharge pattern. Even when the vehicle is started and accelerated, the charging and discharging are performed substantially along the predetermined line although there is some variation, so the present invention is effective.

Next, the configuration of the power system of a hybrid vehicle equipped with the operation system of the present invention will be described. The configuration shown in FIG. 3 is for a parallel hybrid vehicle. In this configuration, an axle 4 is connected to the engine 2 via a transmission 3, and a motor 5 having a rotor that can rotate integrally with the axle 4 is provided. The motor 5 is capable of a generator operation and an electric motor operation. It is. The charging and discharging of the battery 6 connected to the motor 5 is controlled by the CPU 7. The operation of the engine is also controlled by the CPU. The axle 4 is connected to wheels 9 via a differential 8.

The configuration shown in FIG. 4 is for a series hybrid vehicle. In this configuration, a generator 10 is connected to the engine 2, and the generator 10 is electrically connected to the battery 6 and the motor 12 via the controller 11. The controller 11 controls the flow of electric power according to a command from the CPU 7. The motor 12 can perform a generator operation and a motor operation. The rotor of the motor 12 is connected to wheels via a differential 8.

In each type of hybrid vehicle, C
The PU7 includes: an information acquisition unit that acquires height information along the travel route; a pattern determination unit that determines a charge / discharge pattern during traveling based on the height information; a position detection unit that detects a current position; Executing means for executing the control content at the current position according to the pattern.

The information acquiring means can acquire height information of a desired point along the traveling route from a memory storing map information including height information or an external recording medium. The map information may be of a wide area nationwide, or may be of only a target area for route buses or route delivery vehicles. The height information is an altitude value for each key point on the road shown on the map. As the traveling route, a route planned by the driver may be input at any time, a fixed route such as a bus route or a delivery route may be stored in advance, or a route recommended by the car navigation system. Good.

The position detecting means includes a beacon device on the ground and a G
It may be based on the radio wave received from the PS satellite, or based on the instantaneous moving distance detected from the rotation of the wheels and the instantaneous azimuth detected by the gyro. Since these are known position detection methods, their description is omitted.

The pattern determining means applies the current position to the map information, and grasps future road conditions (starting point and ending point of uphill / downhill) from the altitude of the traveling route after the current position on the map. The pattern determination means reads the current remaining charge amount of the battery 6 from a remaining charge amount sensor (not shown), and calculates the remaining charge amount and the optimum charge amount required for the uphill and downhill from the uphill start point and the downhill start point. Is calculated. The pattern determination means calculates the time to reach the start point of ascent and the start point of descent, that is, the start time t2 of the ascent and the start time t5 of the descent. From the uphill start time t2 and downhill start time t5, the scheduled line is extended at a predetermined inclination to determine the charge start time t1 and the discharge start time t4. The charge / discharge pattern during running determined in this way is stored in the memory.

The running means controls charging and discharging in accordance with deceleration and starting / acceleration during normal traveling on a flat road so that the remaining charge amount of the battery is maintained at about 50%. The execution unit refers to the charge / discharge pattern stored in the memory, and when the charge start time t1 or the discharge start time t4 is reached, the remaining charge amount of the battery 6 changes along the charge / discharge pattern even on a flat road. Control the charging and discharging. Further, the execution means refers to the charge / discharge pattern stored in the memory and controls the discharge for backing up the engine or the charging by the braking energy at the uphill start time t2 or the downhill start time t5. The change in the remaining charge amount on an uphill road and the change in the remaining charge amount on a downhill road may be determined in advance as a charge / discharge pattern.

[0034]

The present invention exhibits the following excellent effects.

(1) Since the charging / discharging pattern during traveling is determined based on the height information along the traveling route, the power storage device is prepared at the optimum charge amount before the start of the uphill or before the start of the downhill, and the energy is stored. Can be used effectively.

[Brief description of the drawings]

FIG. 1 is a timing chart of an operation system of a hybrid vehicle according to an embodiment of the present invention.

FIG. 2 is a timing chart of the operation system of the hybrid vehicle showing one embodiment of the present invention.

FIG. 3 is a configuration diagram of a power system of a hybrid vehicle equipped with the operation system of the present invention.

FIG. 4 is a configuration diagram of a power system of a hybrid vehicle equipped with the operation system of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Route bus (hybrid car) 2 Engine 5, 12 Motor 6 Battery 7 CPU 10 Generator

Claims (4)

[Claims] 1. A hybrid vehicle having an engine, a motor connected to a drive shaft of a wheel and driven by a generator / motor, and a power storage device for charging / discharging between the motor, the hybrid vehicle having a driving path along a traveling path. An operation system for a hybrid vehicle, comprising: information acquisition means for acquiring height information; and pattern determination means for determining a charge / discharge pattern during traveling based on the height information. 2. The pattern determining means determines a charge pattern so that the remaining charge amount of the power storage device increases by a time when a hill starts, and determines a discharge pattern such that the remaining charge amount of the power storage device decreases by at least a time when a hill starts. The operation system for a hybrid vehicle according to claim 1, wherein the system is determined. 3. The pattern determining means determines a charge pattern such that the remaining charge amount of the power storage device at the start of the uphill is an optimal charge amount for the subsequent uphill, and the remaining charge of the power storage device at the start of the downhill. The hybrid vehicle operation system according to claim 1 or 2, wherein the discharge pattern is determined so that the amount becomes an optimal amount of charge for a subsequent downhill. 4. The pattern determination means determines a charge pattern so that a target charge amount is recovered by a time when a hill starts climbing when the engine is driven with the most economical efficiency, and only by discharging the power storage device. The operation system for a hybrid vehicle according to any one of claims 1 to 3, wherein a discharge pattern is determined such that a target discharge amount is consumed by a start of a descent when the vehicle travels.