JP2992709B2 - Control device for insulated two-stroke engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an insulated two-stroke engine having a heat insulating structure employing a heat insulating material in a combustion chamber or the like of the engine.

[0002]

2. Description of the Related Art In recent years, in order to improve the thermal efficiency of an engine, a so-called insulated engine has been developed in which a cylinder head, a piston head and the like related to a combustion chamber are insulated so as to maintain combustion energy and maintain a high temperature. ing.

On the other hand, a rotating electric machine is mounted on a turbine shaft of a turbocharger driven by the exhaust energy of an engine, and the rotating electric machine is driven to generate electric power or generate electricity in accordance with the operating state of the engine to energize a supercharging operation. Various attempts have been made to recover exhaust energy.

[0004]

In a two-stroke engine, scavenging is not performed unless the intake boost pressure during scavenging is higher than the exhaust pressure, and two-cycle operation becomes impossible. Therefore, it is necessary to increase the intake boost pressure.

The present invention has been made in view of such a problem, and has as its object to control the operation of a rotary electric machine mounted on a turbocharger in accordance with the conditions of intake boost pressure and exhaust pressure of an adiabatic two-stroke engine. Another object of the present invention is to provide a control device for an adiabatic two-stroke engine that attempts to operate the engine efficiently.

[0006]

According to the present invention, there is provided a thermal insulation system having a turbocharger.
In a control device for a cycle engine, a rotating electric machine arranged on a rotating shaft of the turbocharger and operating electrically / electrically, and an intake boost pressure Pb of the adiabatic two-cycle engine
, An exhaust pressure detecting means for detecting the exhaust pressure Pe of the adiabatic two-stroke engine, a predetermined value ΔP is added to the detected intake boost pressure Pb, and the detected exhaust pressure Pe. Comparing means for comparing the value with the value;
In the comparison of the comparing means, Pb is more than (Pe + ΔP)
Control means for increasing the electric power for driving the electric motor of the rotating electric machine when Pb is larger, and controlling the electric rotating machine to reduce the electric power for driving the electric motor of the rotating electric machine when Pb is larger than (Pe + ΔP); A control device for an adiabatic two-stroke engine, comprising:

[0007]

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of an embodiment of a control device for an adiabatic two-stroke engine according to the present invention.

In FIG. 1, reference numeral 1 denotes an engine, and a heat-insulating material 13 having heat resistance is arranged between a cylinder head 11 and a cylinder sleeve 12, and the heat is transmitted from the cylinder head 11 at a high temperature to the cylinder sleeve 12. A plurality of intake ports 14 are provided below the cylinder sleeve 12 in a peripheral wall portion thereof.

Reference numeral 2 denotes a plurality of exhaust valves arranged in the cylinder head 11, which are simultaneously opened and closed by a plurality of valve operating mechanisms (not shown) to quickly open and close the exhaust passage during scavenging. For example, a heat insulating material such as ceramics is used.

Reference numeral 3 denotes a piston, and a recess 32 serving as a combustion chamber is provided at the center of the upper portion of the piston head 31. The upper portion of the recess 32 is narrowed as a communication hole, for example, about 15% or less of the piston area. And is configured to efficiently burn the fuel injected from the injection nozzle 15 immediately before reaching the top dead center.

The piston head 31 and the piston body 33 are connected by heat insulating gaskets 34 and 35 to block heat conduction from the piston head 31 and, together with the above-mentioned heat insulating material 13 of the cylinder part, to the temperature of the lower part of the engine 1. The rise is prevented. Reference numeral 36 denotes a connecting rod for transmitting the force of the piston 3 lowered by the combustion energy to a crankshaft 37. The crankshaft 37 is provided with an engine rotation sensor 16 for detecting an engine speed.

4 is a turbocharger, a turbine driven by exhaust energy exhausted from an exhaust pipe 21;
A compressor that is driven by the turbine torque and performs a pneumatic operation to pump the supercharged air to the engine,
For example, the exhaust turbine side has a heat insulating structure to effectively use exhaust energy, increase the compression ratio by increasing the diameter of the vane of the compressor, and increase the pressure operation, and an intake pipe connecting the turbocharger 4 and the intake port 14. 4
1 is a boost pressure sensor 4 for detecting the intake boost pressure.
The exhaust pipe 21 is provided with an exhaust pressure sensor 22.

A rotary electric machine 43 is arranged in the turbocharger 4. When electric power is supplied and the electric motor is driven, the turbocharger 4 energizes the pneumatic operation of the compressor to increase the supercharging pressure or has a sufficient exhaust energy. At the time, it is configured to operate with the generator to improve the engine torque by the generated output.

Reference numeral 5 denotes a turbo generator, which is driven by the exhaust gas of the turbocharger 4 to generate power. The power output of the turbo generator 5 is transmitted to a controller, which will be described later, and the rotating electric machine 43 operates at the time of the power generation operation. The motor 6 is driven together with the output of.

The electric motor 6 is connected to the crankshaft 37 of the engine 1 to increase the engine torque. The electric motor 6 serves as a torque increasing means utilizing the recovered electric power by the exhaust energy. The electric power supplied to the electric motor 6 is controlled by a controller. 7 is performed.

The controller 7 comprises a microcomputer, a central control unit for performing arithmetic processing, various memories for storing arithmetic processing procedures and control procedures, input / output circuits,
A strong electric circuit serving as a power conversion mechanism that supplies the electric motor 6 by adding the output of the rotating electric machine 43 and the output of the turbo generator 5 during the power generation operation, or converts the electric power from the battery 73 into the driving electric power of the rotating electric machine 43. Is provided. When a detection signal from an accelerator sensor 72 attached to the accelerator pedal 71 and signals from the engine rotation sensor 16, the exhaust pressure sensor 22, the boost pressure sensor 42, and the like are input, the rotating electric machine is based on these signals. The operation control of the motor 43 and the electric motor 6 is performed.

FIG. 2 is a processing flowchart showing an example of the operation of the present embodiment. The operation of the present embodiment will be described with reference to FIG.

First, in step 1, the engine speed is checked based on the detection signal from the engine speed sensor 17, and if the engine speed is lower than the predetermined speed Na, step 3 is executed.
The process proceeds to step 2 if the rotation speed is high. Then, in step 3, the starter is checked, and if it is on, the rotating electric machine 43 is driven electrically.
A stop signal is issued at and the process returns to step 1.

When the routine proceeds to step 2, the accelerator opening, that is, the engine load is read by the signal from the accelerator sensor 72. In step 6, the accelerator opening L
The boost pressure Pa to be supplied corresponding to a is calculated. In the next step 7, the value of the exhaust pressure Pe from the exhaust pressure sensor 22 is calculated. In the step 8, the value of the intake boost pressure Pb is calculated from the boost pressure sensor 42. To detect.

In step 9, the detected boost pressure Pb
Is compared with the calculated boost pressure Pa. When Pb is much larger than Pa, the rotating electric machine 43 is operated to generate electric power, the exhaust energy is recovered as electric power and supplied to the electric motor 6 to increase the engine torque. Then step 11
The boost pressure is checked at step. If the boost pressure Pa calculated from the pressure Pb is higher, the process proceeds to step 12 to reduce the power generation amount of the rotary electric machine 43. However, if the boost boost pressure Pb is still higher, the process returns to step 10. Thus, the amount of power generated by the rotating electric machine 43 is further increased.

If the detected boost pressure Pb in the comparison in step 9 is not sufficiently larger than the calculated value Pa, the process proceeds to step 13, where the value obtained by adding the minute pressure ΔP to the detected exhaust pressure and the suction boost pressure are calculated. Compare with Pb.

If the suction boost pressure Pb is low, the two-cycle operation cannot be performed. Therefore, the routine proceeds to step 14, in which electric power is applied to the rotating electric machine 43 to urge the supercharging operation to increase the boost pressure. Then, the pressure Pb and Pe + ΔP, which have been increased by the above, are compared. As a result, if the increased boost pressure Pb is large, the power supplied to the rotary electric machine 43 is reduced in step 16 and the process proceeds to step 17, but if Pb is small, the power is increased in step 14 and the boost pressure is further increased. Enhance.

In the flow from step 16, step 1
At 7, the electric power of the rotating electric machine 43 is checked, and the routine proceeds to step 18, where electric power is regenerated by the electric motor 6 coupled to the crankshaft 37.

In step 13 described above, the suction boost pressure P
If b is sufficiently higher than the exhaust pressure Pe, the process proceeds to step 19. In this state, the two-cycle operation is sufficiently possible, so that the rotating electric machine 43 is operated to generate electric power and this electric power is supplied to the electric motor 6 to reduce the engine torque. Increase. Next, at step 20, the suction boost pressure is compared with the exhaust pressure.
Returning to step 9, the generated power of the rotating electric machine 43 is increased, but if there is not much difference from the exhaust pressure, the process proceeds to step 21 to perform control to decrease the generated power of the rotating electric machine 43.

Although the present invention has been described with reference to the above-described embodiment, various modifications can be made within the scope of the present invention, and these modifications are not excluded from the scope of the present invention.

[0027]

As described above in detail, according to the present invention, a rotary electric machine serving as an electric / generator is mounted on the turbine shaft of a turbocharger, and the intake air is always taken from the exhaust pressure Pe of the engine according to the operating state of the engine. Boost pressure is a predetermined value Δ
The electric power of the rotating electric machine is controlled so as to increase by P, and when the intake boost pressure has a sufficient margin, the power generation operation is performed. Therefore, the operation of the adiabatic two-cycle engine is stabilized, and the exhaust energy is well recovered. The effect that the engine is operated efficiently is obtained.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram showing one embodiment of a control device for an adiabatic two-cycle engine according to the present invention.

FIG. 2 is a processing flowchart illustrating an example of the operation of the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine 3 ... Piston 4 ... Turbocharger 7 ... Controller 11 ... Cylinder head 13 ... Heat insulation material 22 ... Exhaust pressure sensor 34, 35 ... Heat insulation gasket 42 ... Boost pressure sensor 43 ... Rotating electric machine 72 ... Accelerator sensor

Claims (1)

(57) [Claims] 1. A control device for an adiabatic two-stroke engine equipped with a turbocharger, comprising: a rotating electric machine arranged on a rotating shaft of the turbocharger and performing an electric / power generation operation; and detecting an intake boost pressure Pb of the adiabatic two-cycle engine. Intake pressure detecting means, exhaust pressure detecting means for detecting the exhaust pressure Pe of the adiabatic two-stroke engine, the detected intake boost pressure Pb, and a value obtained by adding a predetermined value ΔP to the detected exhaust pressure Pe. In the comparison between the comparing means to be compared and the comparing means, (Pe + ΔP)
Control means for increasing the electric power for driving the electric motor of the rotating electric machine when Pb is larger, and controlling the electric rotating machine to reduce the electric power for driving the electric motor of the rotating electric machine when Pb is larger than (Pe + ΔP); A control device for an insulated two-stroke engine, comprising: