JPH05256152A - Two-cycle turbo-compound engine - Google Patents

Abstract

PURPOSE:To efficiently operate a two-cycle engine of such constitution that a turbocharger with an electric rotary machine is fitted to an intake-exhaust passage and that motor-driven mechanism is disposed at a crankshaft. CONSTITUTION:A turbocharger 2 provided with an electric rotary machine 3 is fitted to the intake-exhaust passage of a uniflow type two-cycle engine 1, and a turbine generator 4 is disposed in the exhaust gas passage. A motor- generator 5 is connected to the output shaft of the engine 1, and the electric rotary machine 3, the turbine generator 4 and the motor-generator 5 are controlled in such a way as to boost supercharging pressure to the engine 1 at the partial load time and to drive the motor-generator 5 electrically at the time of large output operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-cycle turbo compound engine in which a turbocharger equipped with a rotary electric machine is attached to a turbine shaft to efficiently collect exhaust energy in a two-cycle engine and to increase engine torque.

[0002]

2. Description of the Related Art In a normal piston reciprocating engine,
It is roughly classified into a two-cycle engine that performs intake, compression, explosion, and exhaust processes in two strokes of a piston, and a four-cycle engine that performs the above-mentioned four processes in four strokes of a piston.
Further, in the two-cycle engine, since the explosion occurs every one rotation of the crankshaft, there is an advantage that the rotation fluctuation of the output shaft is small and high torque can be generated.

However, a two-cycle engine requires some kind of supercharging means. For this reason, a system is used in which a turbocharger is attached to the engine to obtain compressed air for scavenging, and this type of turbocharger is electrically driven. Various attempts have been made to dispose a generator and electrically operate it using a battery as a power source when the engine is operating at a low speed and a high load to urge the pneumatic operation of the turbocharger.

[0004]

As described above, in the case where the motor-generator is attached to the turbocharger and the supercharging pressure is urged by supplying power from the battery, if the electric drive time is long, the battery will rise. However, there is a problem that the boost pressure cannot be increased.

In addition, an electric motor is coupled to the output shaft of the engine, and the power output of a turbocharger motor-generator due to exhaust energy at the time of high engine output is supplied to the electric motor to increase the engine torque. However, there is a drawback that exhaust gas is not collected after driving the turbocharger.

The present invention has been made in view of the above problems, and an object thereof is to prevent the above-mentioned rise of the battery and to efficiently recover the energy of the exhaust gas from the turbocharger to increase the engine torque. The purpose is to provide a 2-cycle turbo compound engine.

[0007]

In order to achieve the above object, according to the present invention, a rotary electric machine is attached to a turbine shaft of a turbocharger connected to a uniflow type two-cycle engine to generate electricity in accordance with an operating state of the engine. In a two-cycle turbo compound engine that supplies the output of the rotating electric machine to an electric mechanism coupled to the output shaft of the engine to energize the engine torque, a turbine generator driven by exhaust gas from the turbocharger and an engine A supercharging pressure increasing means for powering the electric mechanism to power the rotating electric machine to assist pressure operation of the turbocharger at a partial load, and to increase the pressure operation of the turbocharger at the time of full load of the engine and to generate power. Torque that supplies the output of the rotating electric machine and the turbine generator to the electric mechanism 2-cycle turbocompound engine comprising a stage is provided.

[0008]

When the engine is partially loaded, the electric power output of the electric mechanism coupled to the output shaft is supplied to the rotating electric machine, so that the supercharge operation of the turbocharger is assisted, the engine is sufficiently scavenged, and the battery goes up. When the engine requires a large output, it increases the turbocharger's supercharging operation and causes the rotating electric machine to generate power, which is added to the output of the turbine generator and supplied to the electric mechanism to improve the engine torque. ..

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a structural block diagram showing an embodiment of a two-cycle turbo compound engine according to the present invention, and FIG. 2 is an explanatory view from the top of the engine and the turbocharger.

In these drawings, reference numeral 1 denotes an engine which operates in two cycles, and an exhaust valve 11 is provided in the upper part of the head, and an intake port 14 is provided in a cylinder 13 near the bottom dead center of a piston 12. And are connected by an exhaust pipe 21 and a suction pipe 22 having a heat shield structure for intake and exhaust.

The turbocharger 2 has a rotary electric machine 3 as a motor-generator on its turbine shaft, and the turbine 2T is driven by exhaust energy from the engine 1 and supercharged by the pressurized air operation of the coaxial compressor 2C. A motor generator (MG) that serves as an electric mechanism in which air is pumped through the intake pipe 22 and electric power generated by the rotary electric machine 3 is coupled to the flywheel 15 of the engine 1 depending on the operating state of the engine 1. When the electric power is supplied from the MG 5 that is generated by the engine torque to the rotating electric machine 3, the torque of the turbine 2T is assisted to pressurize the compressed air of the compressor 2C. The boosting pressure to the engine 1 is increased and pressure-fed through the intake port 14.

A turbine generator 4 is connected to the exhaust gas outlet 23 of the turbocharger 2 and is driven by the smooth flow of gas energy after driving the turbine 2T to generate electric power. And, the vertical cross-sectional view is shown in FIG. 3, the rotary shaft 43 including the turbine blades 41 and the rotor 42 of the generator is arranged perpendicular to the base 44, and the base 44 has a disk shape. -Shaped magnet 45 is attached, and the magnet 45
The magnet 46 corresponding to is arranged horizontally at the lower end of the rotating shaft 43. The magnets 45 and 46 are magnetized so that the surfaces facing each other have the same magnetic pole property, and the repulsive force of the magnets 45 works to push up the turbine blades 41 and the rotor 4 to reduce the friction. There is.

Reference numeral 6 denotes a controller, which is composed of a microcomputer, and is provided with a central controller, various memories, an input / output circuit, a power converter for converting the voltage and frequency of AC power, and the like. When the rotation signal from the rotation sensor 16 that detects the rotation speed of the engine 1 is input, the rotating electric machine 3 of the turbocharger 2 is changed according to the operating state.
Is configured to control the electric or electric power generation operation of the MG5 or the electric power or electric power generation operation of the MG5 so as to perform the engine operation with good recovery efficiency of the exhaust energy, and further to the MG5 when the engine 1 needs to rotate in the reverse direction. Of the MG5 by changing the control of the phase of the power supplied to the
The reverse rotation of the engine 1 for two cycles can be performed together with the reverse rotation of.

Next, the operation of this embodiment having the above-mentioned structure will be described.
When the partial load operation of the engine 1 is detected by the rotation signal from the engine 6, the electric power from the MG 5 that operates to generate electricity is supplied to the rotating electric machine 3 to assist the rotation of the turbocharger 2 and to perform the pneumatic operation of the compressor 2C. The supercharged air pressure is boosted to send the compressed air from the intake port 14 to the cylinder via the intake pipe 22, so that the operation during partial load is efficiently performed.

Next, when the engine load is large, the exhaust energy becomes large, the driving force of the turbocharger 2 becomes large, the pressure from the scavenging compressor 2C also increases, and the rotary electric machine 3 for generating electricity operates. The output also increases, and the MG 5 to which this electric power is supplied powers to increase the engine torque. Furthermore, the turbine generator 4 driven by the exhaust gas from the turbocharger 2 efficiently regenerates the exhaust gas energy into electric power, and energizes the engine 1 that requires a large output by energizing the MG 5 together with the above-described power generation output of the rotating electric machine 3. Will be done. In this case, the two-cycle engine operates as a combustor, the turbocharger 2 and the turbine generator 4 are combined two-stage multi-stage turbines, and the turbocharger 2 supplies the combustion air to the engine 1 serving as the combustor. While supplying air, the power generation output is added to the output of the turbine generator 4 to operate so as to increase the shaft output.

When the vehicle is moving backward, the controller 6 switches the line of the three-phase alternating current supplied to the MG 5 and the injection timing of the fuel injected into the engine 1 is changed, so that the reverse rotation of the engine can be obtained.

Although the present invention has been described with reference to the above embodiments, various modifications are possible within the scope of the gist of the present invention, and these modifications are not excluded from the scope of the present invention.

[0019]

According to the present invention as in the above embodiments,
MG due to crankshaft rotation when the engine is partially loaded
The power output from the turbocharger is supplied to the rotating electric machine, and the supercharged air from the turbocharger is pressure-fed to the engine through the intake port, so the power from the battery is not needed and the battery can be prevented from going up. Generates electricity from the rotary electric machine, smoothly guides the exhaust gas from the turbocharger to the turbine generator, and supplies the output to the MG together with the output from the rotary electric machine, resulting in a significant increase in engine torque and efficient operation. Is effective.

Further, according to the present invention, the engine can be rotated in the reverse direction by changing the phase of the electric power supplied to the MG and by changing the fuel injection timing, and there is an advantage that the transmission for reverse rotation is unnecessary. ..

[Brief description of drawings]

FIG. 1 is a configuration block diagram showing an embodiment of a two-cycle turbo compound engine according to the present invention.

FIG. 2 is an explanatory view from the top of an engine and a turbocharger and the like in this embodiment.

FIG. 3 is a vertical cross-sectional view of a turbine generator according to this embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Turbocharger 3 ... Rotating electric machine 4 ... Turbine generator 5 ... Motor generator 6 ... Controller 21 ... Exhaust pipe 22 ... Intake pipe 43 ... Rotating shaft 44 ... Base 45,46 ... Magnet

Claims (3)

[Claims] 1. A rotary electric machine is attached to a turbine shaft of a turbocharger connected to a uniflow type two-cycle engine, and the output of the rotary electric machine at the time of power generation is supplied to an electric mechanism connected to an output shaft of the engine according to an operating state of the engine. In a two-cycle turbo compound engine for energizing the engine torque, the turbine generator driven by the exhaust gas from the turbocharger and the electric mechanism to generate electric power when the engine is partially loaded to supply electric power to the rotating electric machine to supply turbo power. The supercharging pressure increasing means for assisting the pressure operation of the charger, the pressure of the turbocharger at the time of full load of the engine, and the output of the rotating electric machine and the turbine generator that have generated power are supplied to the electric mechanism. Two-cycle turbo compound characterized by having a torque increasing means Engine. 2. A two-cycle turbo compound engine according to claim 1, wherein the exhaust flow path and the intake flow path connecting the two-cycle engine and the turbocharger are provided with a heat shield structure. 3. The turbine generator is arranged such that a rotating shaft provided with a turbine blade and a rotor is vertical, and a set of permanent magnets for supporting the weight of a rotating portion by magnetic repulsive force is provided below the turbine generator. The two-cycle turbo compound engine according to claim 1, further comprising a gas flow passage that smoothly receives the exhaust gas from the turbocharger.