JPH10252517A - Braking and auxiliary power device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively use residual energy which can not be used by a turbo charger in power regeneration by providing a power generator in a passage for exhaust current of an internal combustion engine, and regenerating the power generation energy in a storage battery. SOLUTION: An opening of a waste gate valve 16 is controlled to perform supercharging which matches low, medium and high rotating speed rotation ranges of an internal combustion engine 1, and if it exceeds the required supercharging quantity, an opening is enlarged to take out surplus exhaust current. This exhaust current is supplied to an auxiliary turbine 6 to give turning force to a power generator 7 connected thereto. An a.c. power is generated by the rotation of the power generator 7 to be supplied to an auxiliary inverter circuit 8. At this time, a control means 9 takes the terminal voltage of a storage battery 3 from a control circuit 5 through a communicating means 19 to be supplied from the power generator 7 to the auxiliary inverter circuit 8, it is determined whether the voltage of the converted d.c. power exceeds the terminal voltage of the storage battery 3 or not, and if exceeds, the auxiliary inverter circuit 8 is controlled to the charging side to charge the storage battery 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention converts mechanical energy generated when braking an internal combustion engine into electric energy and accumulates the same, and assists the accumulative electric energy when accelerating the internal combustion engine. It is used for a device that generates mechanical energy by supplying it to the device. The present invention relates to an improvement of a hybrid vehicle having both an electric engine and an internal combustion engine.

[0002] The present invention relates to WO 88/061.
No. 07 (International Application No. PCT / JP88 / 00157), which relates to an improvement in the electric braking and auxiliary acceleration device for a motor vehicle. The present invention is a device mounted on an automobile equipped with an auxiliary acceleration and auxiliary braking device sold by the present applicant under the name of HIMR (registered trademark).

[0003]

2. Description of the Related Art The applicant of the present invention directly connects a cage-type polyphase induction machine to a rotating shaft of an internal combustion engine, mounts a storage battery, and uses a main inverter for an AC circuit of the cage-type polyphase induction machine and a DC circuit of the storage battery. A device has been disclosed in which a main inverter circuit is controlled by a computer control circuit that is bidirectionally coupled by a circuit and that receives rotation information of the internal combustion engine and the like as input. This device uses an internal combustion engine to drive as a car, and at the time of climbing or starting a slope, extracts electric energy from a storage battery and drives a cage induction machine as an electric motor to perform auxiliary acceleration. This is a device that operates a polyphase induction machine as a generator, converts rotating mechanical energy generated by braking a vehicle into electric energy, further converts this into DC current, and regeneratively charges a storage battery. This device is
It is evaluated to be extremely effective against environmental pollution because it is possible to recover the energy lost by braking and to make fuel consumption economical and to reduce the amount of exhaust gas emitted when the vehicle accelerates. This device is manufactured and sold by the applicant as HIMR (Hi-M Earl), and as a bus in a national park area where environmental regulations are strict,
It is in a state of being widely adopted as a garbage truck as a regular bus running in urban areas.

[0004] In the case of an internal combustion engine using petroleum fuel, problems concerning the depletion of petroleum fuel and environmental problems have been discussed, and it is expected that automobiles will be switched to electric vehicles equipped with rechargeable storage batteries in the future. Has been a challenge. However, there are still many problems in switching to electric vehicles at once, and there is no hope in a few years that an electric vehicle that can be used practically at a practical price and without inconvenience will be completed. The above-mentioned HIMR has also attracted attention as a hybrid vehicle in the middle of the transition from a vehicle using petroleum fuel to a vehicle using electric energy.

[0005]

The HIMR vehicles described above are currently limited to large vehicles. This is primarily a problem with storage batteries. That is, the current HIMR
Automobiles use a lead-acid battery to store braking energy,
This is used as auxiliary energy during acceleration. Designing a device for a normal vehicle in this form requires, for example, connecting 25 lead-acid batteries in series,
The terminal voltage becomes 280-300V. This battery must be accommodated by providing a large battery compartment in a part of the vehicle body. In a large vehicle, the capacity and weight of this battery is within the range that can be loaded with respect to the volume and weight of the entire vehicle,
In order to apply this HIMR technology to a medium-sized car or a small car, it is absolutely necessary to reduce the size of the battery, which is a bottleneck in development.

In the above-mentioned HIMR, in order to minimize the consumption of petroleum fuel such as gasoline or light oil,
It is necessary to use much electric energy generated by braking, and it is convenient to lengthen the cycle (or interval) of charging the battery at the operation base.

The inventors of the present application have found that although the exhaust gas flowing through the exhaust passage of the internal combustion engine is used for supercharging by the turbocharger, a large amount of energy is still being discarded. We focused on using it for miniaturization.

[0008] On the other hand, there are known several techniques for driving a turbine using an exhaust flow of an internal combustion engine and regenerating the turbine to an output shaft of the internal combustion engine. Further, as a device for providing power generation by providing a branch passage in an exhaust passage and separating it from a turbocharger for performing supercharging, a technique described in Japanese Patent Publication No. 4-5804 is known. In this method, a generator is driven by an excessive exhaust flow to obtain electric energy, and the electric energy is supplied to a motor provided on a main shaft of an internal combustion engine to perform auxiliary acceleration. However, even if the technology disclosed in this publication is examined in detail,
There is no technical idea that the electric energy of the generator driven by the exhaust flow is stored in the battery. Therefore, the regeneration of the auxiliary energy and using it as the auxiliary power must be performed at the same time, and it is not necessarily efficient. Energy regeneration is not always possible.

Japanese Utility Model Publication No. Sho 62-46825 discloses that
The turbine is driven by the excess exhaust flow, and the driving torque is mechanically connected to the output shaft of the internal combustion engine to perform auxiliary acceleration. This requires that energy regeneration and utilization be simultaneous at the same time as in the above-mentioned conventional example, and the structure for mechanically coupling the rotational force must be complicated.

The inventor of the present application has tried to apply the technology based on the turbine generator to the HIMR and conducted a test.
To provide a branch in the exhaust passage to drive the turbine,
It has been found that it is necessary to harmonize with the operation of the turbocharger already equipped in the internal combustion engine, and it is also convenient to use the equipment of the turbocharger already equipped.

The present invention has been made in such a background, and an object of the present invention is to provide a hybrid vehicle in which a cycle or interval for charging a storage battery can be lengthened. An object of the present invention is to provide a hybrid vehicle capable of reducing the size of a battery. The present invention relates to a device for driving a generator using an exhaust flow of an internal combustion engine, and a device for driving a generator by using a turbocharger device already installed in an exhaust and intake passage of the internal combustion engine. An object is to provide a harmonious device.
SUMMARY OF THE INVENTION It is an object of the present invention to effectively regenerate energy of an exhaust stream that cannot be used in a turbocharger to a battery.

[0012]

SUMMARY OF THE INVENTION The present invention is characterized in that a generator is provided in an exhaust flow passage and the generated energy is regenerated to a storage battery. At this time, the control of the turbocharger provided in the exhaust passage is prioritized, and the remaining energy that cannot be used by the turbocharger is used for power generation regeneration.

That is, the present invention provides a cage-type polyphase induction machine (2) connected to a rotating shaft of an internal combustion engine, and a storage battery (3).
A main inverter circuit (4) for bidirectionally converting and coupling an AC circuit of the cage type polyphase induction machine and a DC circuit of the storage battery, and a control circuit (5) for controlling the main inverter circuit. ), A turbine (6) driven by the exhaust flow of the internal combustion engine, a generator (7) connected to the turbine, and an output of the generator. A sub-inverter circuit (8) for converting to direct current and control means (9) for controlling the sub-inverter circuit are provided, and the output of the sub-inverter circuit is supplied to the storage battery.

A turbocharger is already provided in the exhaust passage of the internal combustion engine, and the exhaust passage includes a branch passage that bypasses the turbocharger and a waste gate valve that controls the exhaust flow rate of the branch passage. Already provided. And the turbine is provided in this branch path.

When the turbine is driven by the exhaust flow of the internal combustion engine, a generator connected to the turbine outputs AC energy. The sub-inverter circuit converts this AC energy into DC energy under the control of the control means and charges the storage battery.

The exhaust flow of the internal combustion engine is taken in from a branch provided in an exhaust passage to the turbocharger, and the turbine is driven or stopped by opening and closing an on-off valve. The opening and closing operation of the on-off valve is performed according to the control of the turbocharger. As a result, the control of the turbocharger is prioritized, and the energy of the exhaust gas that cannot be used by the turbocharger can be effectively used without affecting the operation of the turbocharger.

The present invention provides a control circuit for controlling a main inverter circuit for converting an electric energy into an AC circuit of a cage type polyphase induction machine and a DC circuit of a storage battery connected to a rotating shaft of an internal combustion engine. The control circuit for controlling the main inverter circuit and the control means for controlling the sub-inverter circuit are connected by communication means, and the control circuit controls the main inverter circuit according to the control of the control circuit according to the charging state of the storage battery. The control means controls opening and closing of the on-off valve and charging control.

In the case of mass production, by providing the control means for controlling the sub inverter circuit inside the control circuit for controlling the main inverter circuit, the configuration of the control system can be made compact and maintenance and inspection can be performed. The manufacturing cost can be reduced while the manufacturing cost can be improved.

With this configuration, the size of the storage battery can be reduced, and the cycle or interval for charging the storage battery can be lengthened.
It can reduce the consumption of petroleum fuel and contribute to environmental preservation.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION

[0021]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a main part of an embodiment of the present invention.

In the embodiment of the present invention, the cage type polyphase induction machine 2 connected to the rotating shaft of the internal combustion engine 1, the storage battery 3, the AC circuit of the cage type polyphase induction machine 2 and the DC circuit of the storage battery 3 Main inverter circuit 4 for converting and coupling electric energy in two directions
And a control circuit 5 for controlling the main inverter circuit 4. As a feature of the present invention, a sub turbine 6 driven by an exhaust flow of the internal combustion engine 1 and a generator 7 connected to the sub turbine 6 And a sub-inverter circuit 8 for supplying the output of the generator 7 to the storage battery 3, and control means 9 for controlling the sub-inverter circuit 8. The DC output of the sub inverter circuit 8 is regenerated and supplied to the storage battery 3.

The exhaust passage 11 of the internal combustion engine 1 is provided with a turbocharger 14 including a main turbine 12 and a supercharger 13. The exhaust passage 11 has a branch path 15 bypassing the turbocharger 14, and a branch path 15 And a waste gate valve 16 for adjusting the exhaust gas flow rate. The sub turbine 6 is provided in the branch passage 15 and is driven by the exhaust flow. Waste gate valve 1
6 is driven by an actuator 21, which is controlled by the CPU 10.

The supercharger 13 is arranged in an intake passage 18 of the internal combustion engine via a cooler 17 and communicates between a control means 9 for controlling the sub inverter circuit 8 and a control circuit 5 for controlling the main inverter circuit 4. Means 19 are provided. The output of the rotation sensor 20 is connected to the control circuit 5.

Control means 9 for controlling sub inverter circuit 8
May be provided inside a control circuit 5 for controlling the main inverter circuit 4. In the case of mass production, the integrated control system can be integrated by such an integrated configuration, maintenance and inspection can be performed easily, and the manufacturing cost can be reduced.

Next, a control operation in the embodiment of the present invention thus configured will be described.

The exhaust flow of the internal combustion engine 1 is supplied to a main turbine 12 of a turbocharger 14 through an exhaust passage 11. The main turbine 12 is rotationally driven by the supply of the exhaust gas flow, and applies a rotational force to the directly connected supercharger 13. The outside air is taken in by the rotation of the supercharger 13, cooled by the cooler 17, and supplied to the internal combustion engine 1 with high density. If the amount of exhaust gas from the internal combustion engine 1 increases, the rotation speed of the main turbine 12 increases, and accordingly, the rotation speed of the supercharger 13 increases, so that much air is supplied to the internal combustion engine 1. If the amount of the exhaust gas decreases, the exhaust flow to the main turbine 14 decreases, and the supercharging of the internal combustion engine 1 with air decreases.

In this manner, the internal combustion engine 1 is supercharged by using the exhaust flow from the internal combustion engine 1 as a power source. In order to perform the supercharging efficiently, the CPU 10 controls the rotation speed of the internal combustion engine 1. Then, necessary control information including load, torque, and the like are fetched, and the actuator 21 is operated according to the control information to perform opening / closing control of the waste gate valve 16.

That is, in order to perform supercharging matching the low, middle and high speed rotation ranges of the internal combustion engine 1, the waste gate
The opening degree of the valve 16 is controlled, and when the required supercharging amount is exceeded, the opening of the waste gate valve 16 is increased to discharge an excess exhaust flow. When the supercharging amount is insufficient, the opening of the waste gate valve 16 is reduced or closed to increase the exhaust flow rate to the main turbine 12.

The feature of the present invention is to utilize a surplus of the exhaust flow supplied to the main turbine 12 of the turbocharger 14, and generate electric power by the exhaust flow discharged as the surplus to supply the electric power to the storage battery 3. To perform regenerative charging.

FIG. 2 shows a diesel engine according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating an example of performance characteristics of an engine. The vertical axis indicates the torque, and the horizontal axis indicates the rotation speed of the internal combustion engine 1. The hatched portion shown in the figure is an energy region used by the sub turbine 6 provided according to the present invention.

The CPU 10 determines that the rotation speed of the internal combustion engine 1 is N
_t In the following remain closed Ueisuto gate valve 16, and supplies the exhaust stream from the internal combustion engine 1 to the main turbine 12 of the turbocharger 16, the rotational speed reaches the N ₁ exceed N, and torque from t t _Since the energy required by the turbocharger 14 in one is exceeded, the waste
The opening degree of the gate valve 16 is adjusted to extract an excess exhaust flow.

The extracted exhaust stream is supplied to the sub-turbine 6 and applies a rotational force to a generator 7 directly connected to the sub-turbine 6. AC power is generated by the rotation of the generator 7 and supplied to the sub inverter circuit 8. At this time, the control means 9
The terminal voltage of the storage battery 3 is fetched from the control circuit 5 via the communication means 19, and whether or not the voltage of the DC power supplied from the generator 7 to the sub-inverter circuit 8 and converted exceeds the terminal voltage (V) of the storage battery 3 Is determined, and if it exceeds, the sub-inverter circuit 8 is controlled to the charging side to charge the storage battery 3.
When the voltage of the DC power converted by the sub inverter circuit 8 falls below the terminal voltage (V) of the storage battery 3, the charging of the storage battery 3 from the sub inverter circuit 8 is stopped.

The terminal voltage (V) of the storage battery 3 is not constant but fluctuates constantly. That is, under the control of the control circuit 5, the AC output from the squirrel-cage polyphase induction motor 2 connected to the rotating shaft of the internal combustion engine 1 is converted into DC power by the main inverter circuit 4 during auxiliary braking, and the rechargeable battery 3 is recharged. Is done. During auxiliary acceleration, DC power is extracted from the storage battery 3, converted into AC power by the main inverter circuit 4, and the cage-type polyphase induction motor 2 is driven as an electric motor to perform auxiliary acceleration. Therefore, as shown by the solid line in FIG. 3, the terminal voltage (V) of the storage battery 3 differs depending on the normal running, the auxiliary acceleration, and the auxiliary braking. The control circuit 5 always takes in the value of the terminal voltage (V) from the storage battery 3, and the control means 9 inputs this value via the communication means 19, and when the value is in the shaded portion in FIG. As shown by the two-dot chain line in FIG.
Control is performed so as to exceed V, and regenerative charging of the storage battery 3 is performed by the sub inverter circuit 8.

The specification of the power turbine used as the auxiliary turbine 6 in this embodiment is a maximum output of 7 kW, an allowable rotation speed of 100,000 rpm, and the specification of the generator 7 is a model of a three-phase permanent magnet type synchronous machine fully closed type. The output is 6 kW and the operating speed is 50,000 to 80,000 rpm.

As described above, the energy remaining in the exhaust flow has been conventionally used for the turbocharger. However, in the region where the rotational speed exceeds a certain rotational speed due to the performance characteristics of the diesel engine, there is still room to use the exhaust flow. Yes, this was recovered by the turbo alternator of the present invention. Thereby, by giving priority to the control of the turbocharger, the interaction with the turbocharger is minimized,
The present invention can be implemented.

[0037]

As described above, according to the present invention, without affecting the operation of the turbocharger already installed in the exhaust passage and the intake passage of the internal combustion engine,
Exhaust energy can be effectively used to regenerate electrical energy, thereby reducing the size of the storage battery and extending the charging cycle or interval.
Further, it is possible to reduce the consumption of petroleum fuel and contribute to environmental conservation.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a main part of an embodiment of the present invention.

FIG. 2 is a diagram showing an example of performance characteristics of the diesel engine according to the embodiment of the present invention.

FIG. 3 is a view for explaining a state of fluctuation of a storage battery terminal voltage according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Cage type polyphase induction machine 3 Storage battery 4 Main inverter circuit 5 Control circuit 6 Sub turbine 7 Generator 8 Sub inverter circuit 9 Control means 10 CPU 11 Exhaust passage 12 Main turbine 13 Supercharger 14 Turbocharger 15 Branch path Reference Signs List 16 waste gate valve 17 cooler 18 intake passage 19 communication means 20 rotation sensor 21 actuator

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B60L 11/12 B60L 11/12 F01N 5/04 F01N 5/04 B F02B 37/00 302 F02B 37/00 302B H02P 9/04 H02P 9/04 F

Claims (4)

[Claims] 1. A cage-type polyphase induction machine (2) connected to a rotating shaft of an internal combustion engine, a storage battery (3), and an AC circuit of the cage-type polyphase induction machine and a DC circuit of the storage battery. Main inverter circuit that converts and couples electric energy in the direction (4)
And a control circuit (5) for controlling the main inverter circuit, wherein the turbine (6) is driven by an exhaust flow of the internal combustion engine.
A generator connected to the turbine, a sub-inverter circuit for supplying the output of the generator to the storage battery, and control means for controlling the sub-inverter circuit. A braking and auxiliary power unit for an internal combustion engine, characterized in that: 2. A turbocharger is provided in an exhaust passage of the internal combustion engine. The exhaust passage includes a branch passage that bypasses the turbocharger, and a waste gate valve that controls the exhaust flow rate of the branch passage. The braking and auxiliary power unit according to claim 1, wherein the turbine is provided in the branch path. 3. The braking and auxiliary power device according to claim 1, wherein communication means is provided between control means for controlling the sub inverter circuit and a control circuit for controlling the main inverter circuit. 4. The braking and auxiliary power device according to claim 1, wherein the control means for controlling the sub inverter circuit is provided inside a control circuit for controlling the main inverter circuit.