JPH0337328A - Controller for turbocharger - Google Patents

Abstract

PURPOSE:To economize the electric power and prevent the surging of a compressor by opening a valve in a bypass passage only on the start of flying boost-up and introducing a portion of the compressed air of the compressor of a turbocharger into a turbine. CONSTITUTION:When an engine 1 is in low speed and high load operation, an electric rotary machine 3 installed onto a rotary shaft 23 for connecting the turbine 21 and the compressor 22 of a turbocharger 2 is power-running- operated as electric motor, and the revolution speed of the compressor 22 is increased to assist the supercharge operation. In this case, each bypass pipe 4 is arranged at the inlet of the turbine 21 and the outlet of the compressor 22, and a valve 41 is arranged midway. The valve 41 is opening/closing- controlled by a controller 6 on the basis of each detection signal of the sensors 11 and 61 - 63 for detecting the operation state of the engine. In other words, the valve 41 is opened only in the initial stage of the flying boost-up operation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a turbocharger control device that controls the operation of a turbocharger in which an electric mechanism is attached to a turbine shaft.

(Prior art) A supercharger uses exhaust energy to guide the exhaust gas emitted by an engine to a turbine and rotate it at high speed, and to drive the compressor by placing it on the rotating shaft of the turbine to supercharge the intake air of the engine. It has been known since ancient times.

Then, there is a proposal to attach an electric mechanism that serves as an electric generator to the turbine shaft of this type of exhaust turbine-driven supercharger, and to operate the electric mechanism as an electric motor or a generator/electric generator depending on the operating state of the engine. A variety of things have been done.

On the other hand, in a turbocharger equipped with such an electric mechanism, the rotation speed of the compressor is separately increased to increase the boost pressure to the engine, regardless of the operating state of the engine.

This is called flying boost-up, and for example, although the engine speed is idling, it determines that the vehicle is about to start based on the transmission control system, clutch operation system, etc., and energizes the electric mechanism of the turbocharger. The practice is to drive at high speed and increase boost pressure.

(Problem to be solved by the invention) When starting the flying boost up as described above,
The power consumption from the battery, which is the power source for the electric mechanism of the turbocharger, is large, and if the initial large current or longer energization time is used, the amount of charge stored in the battery will decrease, and there is a risk that so-called battery exhaustion may occur.

Furthermore, when the engine is in an idle state and the rotational speed is low, the air flow rate is small, so if the rotational speed of the turbocharger is increased to a high rotational speed, the surge line will be exceeded as shown in the curve diagram shown in FIG.

The present invention was made in view of such problems,
The purpose is to provide a turbocharger control device that saves power at the start of flying boost-up of the turbocharger and prevents compressor surging.

(Means for Solving the L1 Problem) According to the present invention, in a control device for a turbocharger that assists supercharging operation by causing a rotating electric machine provided on a rotating shaft connecting a compressor and each impeller of a turbine to power running operation. There is provided a turbocharger control device that is provided with a bypass flow path that communicates the outlet of the compressor with the inlet of the turbine, and is provided with opening/closing control means that opens the bypass flow path only at the beginning of a flying boost-up operation.

(Function) In the present invention, a bypass flow path is provided between the compressor outlet and the turbine inlet of the turbocharger, and the flow path is controlled to open at the start of flying boost-up, so that part of the compressor pressure air flows through the bypass flow path. energizes the rotation of the turbine.

Therefore, it is possible to increase the boost pressure by supplying a small amount of power from the battery to the rotating electric machine.

On the other hand, since pressure air is supplied from the compressor to the turbine, the air flow rate of the compressor increases even when the engine is in an idling state.

(Example) Next, an example of the present invention will be described in detail using the drawings.

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

In the figure, reference numeral 1 denotes an engine, which drives the vehicle using the combustion energy of supplied fuel, and is equipped with a rotation sensor 11 for detecting the engine rotation speed.

Reference numeral 2 denotes a turbocharger, which includes a turbine 21 driven by the energy of exhaust gas discharged from the exhaust pipe 12 of the engine 1, and a compressor 22 driven by the turbine torque to forcefully send intake air to the engine 1 through the intake pipe 13. A rotating electric machine 3 serving as an electric motor-generator is attached to a rotating shaft 23 that connects the turbine 21 and the compressor 22 as an electric mechanism.

When the engine 1 is rotating at a low speed and under a high load, power is supplied to the rotating electric machine 3 to run it as an electric motor, increasing the rotation speed of the compressor 22 and assisting its supercharging operation, thereby increasing the engine output. On the other hand, when the engine 1 rotates at high speed and the exhaust energy is large, the rotating electric machine 3 is operated as a generator to convert the exhaust energy into electric power and charge the battery 5.

4 is a bypass pipe, which connects the outlet of the compressor 22 and the turbine 2! A valve 41 is disposed in the middle of the bypass pipe 4 to short-circuit and guide the pressurized air from the compressor 22 to the turbine 21 . Normally, the valve 41 is closed and the exhaust gas from the engine 1 is guided to the turbine 21, and the compressor 22
Pressure air from the compressor 22 is supplied to the engine 1 through the intake pipe 13, but when the valve 41 is opened, a part of the pressure air from the compressor 22 is introduced into the turbine 21.
rotation will be energized and the air flow rate of the compressor will be increased.

Reference numeral 5 denotes a battery, which is mounted on the vehicle and serves as a power source for auxiliary equipment and the rotating electrical machine 3 during electric operation, and is charged by the generated power C when the rotating electrical machine 3 is operating to generate electricity.

6 is a controller, consisting of a microcomputer;
It is equipped with a central control unit that performs arithmetic processing, various memories that store arithmetic processing procedures and control procedures, and input/output ports. A rotation sensor 11 of the engine 1, a clutch sensor 61 that detects clutch ON/OFF, a gear sensor 62 that detects the gear stage of the transmission, a vehicle speed sensor 63 that detects vehicle speed, etc. are connected to the input boat. When signals from various sensors are input, predetermined processing is performed according to the procedure stored in the memory, and the bypass pipe 4 &
: The opening/closing control of the valve 41 is performed at the installation.

FIG. 3 is a process flow diagram showing an example of the process of this embodiment in a manual vehicle, and the process will be explained using the same figure.

In step l, the engine speed N ENO is compared above the idle speed, e.g.
If the rotation is below, proceed to step 2 and check clutch sensor 6.
Based on the signal from 1, it is checked whether the clutch is disengaged or not. If the clutch is disengaged, the process proceeds to step 3, and the signal from the gear sensor 62 (if the gear position is 1st), the vehicle speed is checked in the next step 5, and 5k+
If it is less than a/hour, the coefficient N is set to 1 in step 6. During this time, if the engine rotation is 700 rpm or more, the clutch is engaged, the gear is other than 1st, and the vehicle speed is 5 km or more, proceed to step 14 without following the step order.
You will have to wait for a while and then go back to step 1 and repeat.

After setting the coefficient N to 1 in step 6, in step 7 the electric power from the battery 5 is supplied to the rotating electrical machine 3 to drive it as an electric motor to power it, and the flying boost up starts, and then in step 8 the bypass The valve 41 provided in the pipe 4 is opened. Therefore, part of the pressure air from the compressor 22 is introduced into the turbine 21 and the turbine is energized, and electrical energy corresponding to the energy of this pressure air is generated. Power will be saved.

In addition, even when the amount of air at idle is extremely restricted by the throttle valve, such as in a gasoline engine, the flow rate of the compressor is reduced because the valve 41 is opened and pressure air from the compressor 22 is sent to the turbine 21 side as well. As a result, the occurrence of surges can be suppressed.

In step 9, enter the value of the coefficient N plus 1,
At each step 10, it is checked whether or not it is in acceleration mode, and if it is in acceleration mode, it proceeds to step 11 to cancel the operation of the flying boost up, and at the same time, in step 1
In step 2, the valve 41 is closed and normal turbocharger control is performed.

If the vehicle is not in the acceleration mode in step 10, the vehicle speed is checked in step 15, and if the vehicle speed is 5 km or more, the process proceeds to step 16.17 where the valve 41 is closed and the power from the battery 5 to the rotating electric machine 3 is cut off to increase the flying boost. stop operating.

In addition, if the vehicle speed does not reach 5 km in step 15, the coefficient N is compared with the coefficient No that determines the duration of the initial flying boost up in step 18.
If the coefficient N is large, proceed to step 19.20 &: close the valve 41 and stop power supply to the rotating electric machine 3.

Note that if the coefficient N does not reach No in step 18, the process returns to step 9 and the flow is repeated.

Next, FIG. 4 is a process flow diagram showing an example of the process of this embodiment in a vehicle equipped with an automatic transmission.

In this figure, only steps 1° to 4° leading to the execution of flying boost-up at the initial stage of the flow differ from the process flow diagram of FIG. 3, and steps from step 5 onwards are the same as the above-described process flow diagram.

Therefore, when the engine speed is 700 rpm or less, the gear is in the D range, the brake is pressed, and the vehicle speed is less than 1 in 5, the coefficient N is set to 1, and the operation of the flying boost up is started. It turns out.

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

(Effects of the Invention) According to the present invention, a bypass passage is provided between the outlet of the compressor of the turbocharger and the intake of the turbine, and a valve is arranged to open and close the passage. By opening the valve and introducing a portion of the compressor's pressure air into the turbine via the bypass flow path, the turbine's rotational speed increases, making it possible to minimize the initial power supply from the battery. .

On the other hand, the pressure from the compressor is guided to the turbine via the bypass flow path, so even if the engine is idling and the air flow is throttled, the amount of air flowing through the compressor increases and surges are prevented. This gives rise to the advantage of

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of an embodiment of the present invention, Fig. 2 is a curve diagram showing the relationship of the surge line to the air flow rate and pressure ratio of the compressor, and Fig. 3 is the processing of this embodiment in a manual vehicle. Flowchart FIG. 4 is a processing flowchart of this embodiment in an automatic vehicle. 1...Engine, 2...Turbocharger, 3...
- Rotating electric machine, 4... Bypass passage, 21... Turbine, 22... Compressor, 41... Valve.

Claims (1)

[Claims] In a turbocharger control device that assists supercharging operation by powering a rotating electric machine installed on a rotating shaft that connects each impeller of a compressor and a turbine, a bypass flow path is provided that communicates the outlet of the compressor and the inlet of the turbine. A control device for a turbocharger, further comprising an opening/closing control means for opening the bypass passage only in the initial stage of a flying boost-up operation.