JPH0565830A - Control device for two cycle turbo compound engine - Google Patents

Abstract

PURPOSE:To constitute a turbo compound system excellent in efficiency by providing two turbo chargers, each of which is equipped with a rotating electric machine, for the exhaust passages of a two cycle adiabatic engine so as to be mutually connected in parallel, and concurrently switching the exhaust passages and controlling the rotating electric machines. CONSTITUTION:Turbo chargers 2 and 3 which are furnished with rotating electric machines 23 and 33 respectively, are mounted onto the group of cylinders representing a half of the whole cylinders of an engine in number. And valves 41 and 43 and the like are arranged for passages in such a way that one turbo charger 3 is out of action. The turbo chargers 2 and 3 and the rotating electric machines 23 and 33 are controlled in action based on signals from an engine revolution sensor 17, a load sensor 72 and a boost pressure sensor 16, so that efficiency as a turbo compound system can be enhanced in a range from partial load operations up to full load operations.

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 for recovering the exhaust energy of a two-cycle engine having a heat insulating structure into electric power and supplying the electric power to an electric motor connected to a drive system of the engine to increase torque. The present invention relates to an engine control device.

[0002]

2. Description of the Related Art A portion related to a combustion chamber of an engine has a heat insulating structure to maintain a high temperature, guides high temperature exhaust gas to a turbine for rotational driving, and uses a generator connected to a turbine shaft to convert exhaust energy into electric power. While regenerating,
On the other hand, various types of turbo compound engines in which an electric motor is connected to a crankshaft of the engine and electric power regenerated by the electric motor is supplied to increase the engine torque have been tried.

In this type of system, a turbocharger is usually attached to the exhaust manifold of an adiabatic engine, and the turbocharger is driven so that exhaust gas after driving the turbocharger drives a turbine generator for energy recovery. And a turbine generator are connected in series to the exhaust flow.

[0004]

In the turbo compound system as described above, the electric power recovered by the turbine generator can be used for increasing the engine torque, but the pressure difference between the turbine inlet and outlet of the turbocharger and the recovery Since the product of the pressure difference between the inlet and outlet of the turbine for use is loaded on the engine, there is a problem that the performance of the integrated turbo compound system deteriorates.

The present invention has been made in view of the above problems, and an object thereof is to connect two turbochargers in parallel to the exhaust flow of a two-cycle engine having a heat insulating structure to form a turbo compound system. It is an object of the present invention to provide a control device for a two-cycle turbo compound engine, which is intended to increase efficiency and improve performance under partial load of the engine.

[0006]

In order to achieve the above-mentioned object, according to the present invention, exhaust energy of a two-cycle engine having a heat insulating structure in a portion related to a combustion chamber is recovered as electric power to drive the engine. In a control device of a two-cycle turbo compound engine for supplying electric power recovered to an electric motor connected to a system, two turbochargers with rotating electric machines connected in parallel to an exhaust passage of the engine,
A flow path closing means for closing an exhaust flow path to one turbocharger with a rotating electric machine, a rotating electric machine switching means for switching the operation of the rotating electric machine to an electric drive / power generation operation, and the above according to an engine speed and an engine load. There is provided a control device for a two-cycle turbo compound engine, which comprises control means for selectively controlling the flow path closing means and the rotary electric machine switching means to control supercharging of the engine and energization of the electric motor.

[0007]

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

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

In the figure, reference numeral 1 denotes an engine, which is a two-cycle adiabatic engine that insulates a portion related to its combustion chamber and does not perform cooling, and is a four-cylinder engine having cylinders A to D.

Reference numeral 2 is a turbocharger, which is a cylinder A, B.
21 driven by being connected to the exhaust pipe 11 from
And a compressor 22 for performing pressure operation by the turbine torque, and the pressure air is pressure-fed to each intake port of the engine 1 via the intake pipe 13 and the cooler 14. Further, 3 is also a turbocharger, which is connected to the exhaust pipe 12 from the cylinders C and D via a flow path having a valve 42, is equipped with a turbine 31 and a compressor 32, and has a compressed air outlet 34 of the compressor 32. The above-mentioned air inlet 24 of the compressor 22 is guided by the connecting pipe 35 to perform a two-stage pneumatic operation in series.
An air inlet 36 and a valve 43 are arranged in the middle of the flow path. When the valve 43 operated by the flow path switching unit 52 shuts off the connecting pipe 35, the flow path from the air inlet 36 is opened and air is supplied to the compressor 22. It is configured to be guided. In addition,
As described above, the exhaust pipe 11 and the exhaust pipe 12 are connected to each other by a flow path having a valve 41 at their ends, and when the valve 41 is opened by the operation of the flow path selector 51, the exhaust pipe 11 is opened.
And 12 communicate with each other, but the above-mentioned valve 42 is closed, and exhaust gas from all four cylinders of the engine 1 is transferred to the turbine 2
1 will drive only the turbocharger 2, and when the valve 41 is closed by the flow path switching device 51, the valve 42 will be opened, and the turbochargers 2 and 3 will be for two cylinders, respectively. It is configured to be driven by exhaust energy.

The flow path selectors 51 and 52 are operated by a fluid pressure, 50 is a pressure tank, 53 is an operation valve for the flow path selector 51, and 54 is a flow path selector 52. Actuating valve for use, and is controlled by a command from a controller described later.

Reference numerals 23 and 33 denote rotary electric machines (TCGs) serving as motor-generators, respectively, and turbines 21 and 3
When the turbine torque driven by the exhaust energy is large, the generator 1 is attached to each rotating shaft of No. 1 to generate electric power, and the generated power is supplied to the electric motor 6 having the pinion 61 via the controller 7, It drives the large gear 15 of the shaft to energize the engine torque, and when the desired boost pressure cannot be obtained, electric power is supplied from the battery 71 as a power source to drive the motor as a motor. It is configured to assist the pneumatic operation of the compressor.

The controller 7 is composed of a microcomputer, has a central control unit, various memories, input / output ports, etc., and receives signals from the boost pressure sensor 16, the engine rotation sensor 17, the load sensor 72, etc.
Based on a predetermined calculation and control procedure, the above-mentioned actuating valves 52, 5
4 and the rotary electric machines 23, 33, etc. are configured to issue appropriate commands to perform control.

FIG. 2 is a process flow chart showing an example of the operation of this embodiment. Next, the operation of this embodiment will be described with reference to this figure.

The signal from the engine rotation sensor 17 is read in step 1 and the signal from the load sensor 72 is read in step 2. Then, in step 3, the read rotation speed N is compared with the predetermined rotation speed Na, and if N <Na, the load L read in step 4 is compared with the predetermined load La,
In the case of L <La, the operation valve 53 is instructed and the flow path switch 51
Is operated to open the valve 41, close the valve 42, and operate the flow path switch 52 to close the valve 43. Therefore, the exhaust gas from the four cylinders of the engine 1 is guided only to the turbine 21, and the air from the air inlet 36 is compressed by the pressure operation of the compressor 22, and the air from the intake port of each cylinder is passed through the cooler 14 and the intake pipe 13. It is pumped and operated,
Then is compared to a predetermined value P _B a boost pressure P _B by the signal from the boost pressure sensor 16 in step 6, P
_{When B} is large, the power generation of the TCG 23 is increased and transmitted to the electric motor 6. (First area)

If the L read in the above step 4 is larger, the process proceeds to step 8, where L of a predetermined load is set.
b. When L <Lb, in step 9, the valve 41 is closed and the valves 42 and 43 are opened by the flow path selectors 51 and 52, and the TCGs 23 and 3 are connected.
3 is activated. Then, although checks a boost pressure at step 10 is P _B when greater than the predetermined value P _B a increase power generation at step 11, reducing the power generation at step 12 when the unreached to P _B a Control. (Second area)

If the load L is larger in step 8 described above, the process proceeds to step 13 where the load L is compared with Lc having a value larger than Lb. When L <Lc, the process proceeds to step 14 to open the valve 41, the valve 42 and the valve 43.
And are controlled to be closed, the turbocharger 2 is not operated, and the supercharged air is pumped to the engine 1 only by the turbocharger 2.
In step 15, the TCG 23 is electrically driven by the electric power of the battery 7 to assist the compressor 22. (3rd area)

Next, at step 16, the boost pressure P _B at this time is compared with a predetermined value P _B c, and when P _B is large, the power from the battery 71 is reduced to decrease the output of the TCG 23, but P _B is When P _B c has not been reached, the supply power is calculated to increase the supply power to the TCG 23 and increase the boost pressure P _B.

The load L and Lc in step 13
If the load L is large in comparison, the process proceeds to step 20 and the valve 4
1.Turbo charge by controlling valve 43 to open and valve 42 to close.
2 is driven by engine exhaust energy and TCG2
3 electric drive, turbocharger 3 is TCG 33 electric drive
Driven to generate compressed air from the two-stage supercharging operation to the engine 1
Supply to. (4th area) And in step 21
Strike pressure P_B Is a predetermined value P _B P compared to c_B When is large
Reduces the power supplied to TC32, but P_B Is P_B not yet in c
When it reaches the limit, the increase of the power to the TCG 33 is calculated, and the step
22 to supply the electric power to increase the torque of the TCG 33.
The boost pressure to the engine 1 should be increased.
It

On the other hand, when the engine is rotating at high speed and N is larger than the predetermined value Na in step 3 described above, the routine proceeds to step 25, where the load L is compared with the predetermined load value Ld. And L <
If Ld, proceed to step 26, open valve 41,
2, 43 are closed to drive the turbocharger 2 to operate the TCG 23 for power generation. Next, at step 27, the boost pressure P _B is compared with a predetermined value P _B d, and P _B > P
When it is _B d, the power generation of the TCG 23 is increased in step 28.

When the load L is larger than Ld in step 25, the routine proceeds to step 29, in which the valve 42 and the valve 43 are opened and the valve 41 is closed to drive both the turbochargers 2 and 3 and the TCG 23. , 33 to generate electricity. Next, at step 30 compares the boost pressure P _B and the predetermined value P _B e, when the P _B> P _B e TCG
The generated power of 23 and 33 is increased and transmitted to the electric motor 6 to increase the engine torque.

3 is a control map in this embodiment, and FIG. 4 is a diagram showing the operation of this embodiment by region.

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.

[0024]

According to the present invention as in the above embodiments,
Exhaust gas from a heat-insulated two-cycle engine can be supplied in parallel to two turbochargers with rotating electric machines, or
Since it is configured so that it can be supplied only to the turbocharger system, when the two turbochargers are driven, since the turbines are in parallel, the pressure difference between the turbine inlet and outlet is not added to the engine as a product, and the turbo compound system As a result, it is possible to obtain the effect of preventing performance degradation.

Further, according to the present invention, since the exhaust gas from the adiabatic engine has a large amount of heat energy without being cooled,
In the present embodiment configured as described above, two turbochargers in parallel can be sufficiently driven near the full load of the engine, and switching of two or one turbocharger at the time of partial load and rotating electric machine The power generation / electricity switching control has the advantage of being able to perform appropriate region-specific control according to the engine speed and load.

[Brief description of drawings]

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

FIG. 2 is a process flow chart showing an example of the operation of the present embodiment.

FIG. 3 is a control map diagram in the present embodiment.

FIG. 4 is a chart showing the operation of this embodiment by region.

[Explanation of symbols]

 1 ... Engine 2 ... Turbocharger 3 ... Turbocharger 6 ... Electric motor 7 ... Controller 11 ... Exhaust pipe 12 ... Exhaust pipe 16 ... Boost pressure sensor 17 ... Engine rotation sensor 23 ... Rotating electric machine 33 ... Rotating electric machine 72 ... Load sensor

Claims (1)

[Claims] 1. The exhaust energy of a two-cycle engine having a heat insulating structure in a portion related to a combustion chamber is recovered as electric power,
In a control device for a two-cycle turbo compound engine, which supplies recovered electric power to an electric motor connected to a drive system of the engine, two turbochargers with rotating electric machines connected in parallel to an exhaust passage of the engine, and one of A flow path closing means for closing an exhaust flow path to the turbocharger with a rotating electric machine, a rotating electric machine switching means for switching the operation of the rotating electric machine to an electric drive / power generation operation, and the flow according to the engine speed and the engine load. A control means for selectively controlling the passage closing means and the rotary electric machine switching means to control supercharging of the engine and energization of the electric motor is provided.
Cycle turbo compound engine controller.