JPH01104948A - Controller for turbocharger equipped with electric rotary machine - Google Patents

Abstract

PURPOSE:To obtain the always proper air fuel ratio by obtaining the intake boost pressure which is necessary in accordance with the stepping quantity of an accelerating pedal and calculating the proper fuel feed quantity corresponding to the boost pressure and correcting the supercharge operation of the intake and the fuel flow rate. CONSTITUTION:A turbocharger 2 is equipped with a turbine 2b driven by exhaust gas and a compressor 2a which is revolved by the power of the turbine 2b through a rotary shaft 2c and supercharges intake into an engine 1. An electric rotary machine 3 which operates as electric motor or dynamo is installed onto the rotary shaft 2c. In this case, the difference between the acceleration corresponding boost pressure calculated from the output of an acceleration sensor 1c and the actual boost pressure detected by a boost sensor 1j is calculated, and when the difference is larger than a prescribed value, the supplied electric power into the electric rotary machine 3 which is necessary for acceleration is calculated, and the electric rotary machine 3 is operated. Further, at the same time, a fuel actuator 7 is controlled in correspondence with the increase of the boost pressure, and fuel supply is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Applicability) The present invention relates to a control device for a turbocharger with a rotating electrical machine, in which an electric motor-generator is attached to the rotating shaft of the turbocharger.

(Prior Art) Various proposals have been made to recover exhaust energy by attaching a turbocharger to the exhaust pipe of an engine and directly connecting an electric motor-generator to the rotating shaft of the turbocharger.

As a proposal for attaching a motor-generator to such a turbocharger, control of an internal combustion engine turbocharger is possible by operating the motor-generator or operating the motor according to engine speed and load conditions. Proposals for the device have been made, for example, in Japanese Patent Application No. 105981/1981 and Japanese Patent Application Laid-Open No. 60-198.
No. 5329.

(Problems to be Solved by the Invention) In such a proposed turbocharger with a rotating electric machine, generated power is supplied to the electrical load or battery when the motor-generator generator is operating, and when the motor is operating, the turbocharger is supplied with generated power. The engine output is improved by assisting supercharging, but when the boost pressure of the turbocharger is increased in response to changes in vehicle driving conditions, the fuel flow rate is also adjusted appropriately according to the increase in boost pressure. Optimal air/
There is no means for controlling the engine to operate depending on the fuel ratio. Therefore, even when the vehicle is under running conditions that require rapid acceleration, there is a problem in that desired acceleration cannot be achieved due to insufficient driving force from the engine. There was also the problem that the exhaust gas turned into black smoke due to an inappropriate air/fuel ratio.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a control device for a turbocharger with a rotating electrical machine that attempts to solve the above-mentioned problems by controlling the air/fuel ratio so that the optimum air/fuel ratio is always obtained depending on the driving conditions of the vehicle. It is in.

A further object of the present invention is to provide a control system for a turbocharger with a rotating electric machine that diagnoses the occurrence of failures such as breakage of turbine blades or the introduction of foreign matter when the boost pressure is assisted by the operation of the electric motor of the rotating electric machine. It is about providing.

(Means for Solving the Problems) According to the present invention, there is provided a turbocharger with a rotating electrical machine that is connected to the exhaust pipe of an internal combustion engine and that supercharges intake air using exhaust energy. In the charger control device, an accelerator pedal depression amount detecting means for the internal combustion engine, a boosting means for driving an electric rotating machine to boost the pressure of supercharging air according to a signal from the detecting means, and supercharging by the boosting means. It is possible to provide a control device for a turbocharger with a rotating electric machine, which is provided with a fuel control means for controlling the fuel supply amount corresponding to the pressure.

(Function) In the present invention, the necessary boost pressure of intake air is calculated in accordance with the amount of depression of the accelerator pedal, and the amount of fuel supplied to this boost pressure is also calculated, and the supercharging operation and fuel flow rate are corrected respectively. Therefore, there is an effect that an appropriate air-fuel ratio can always be obtained.

Furthermore, when assisting supercharging operation, the power supply to the rotating electric machine operated by the motor and the amount of work done by the motor are checked, and if there is an abnormality, it is determined to be a failure.

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

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

In FIG. 1, reference numeral 1 denotes an engine that drives a vehicle (not shown) by the combustion energy of air taken in through an intake pipe 1a and fuel supplied through a fuel passage 7a. Exhaust gas after combustion is discharged via 1b. 1c is an accelerator sensor that detects the amount of depression of the accelerator pedal, 1d is a load sensor that detects the engine load based on the rack position of the fuel injection pump (not shown) of engine 1, and 1e is a rotation sensor that detects the engine rotation speed. Detected signals are sent to an electronic control unit, which will be described later. A fuel actuator 7 is provided in the fuel passage 7a, and the amount of fuel supplied is controlled by an electronic control device, which will be described later.

2 is a turbocharger connected to the exhaust pipe 1b and the intake pipe 1a, and the turbine 2 is driven by exhaust gas.
A rotary electric machine 3 that operates as an electric motor or a generator is attached to a rotating shaft 2c that connects these components. 1f is a partition wall provided in the exhaust pipe 1b, which is attached to the exhaust passage that drives the turbine 2b and divides the passage into two; an exhaust valve 1g is attached to one passage; When the amount of gas is small, the actuator 1h closes the bypass valve 1g to increase the exhaust gas flow velocity in the other flow path, thereby efficiently driving the turbine 2b at a high speed. Note that 2d is a turbine rotation sensor that detects the rotation speed of the rotating shaft 2c.

The rotating electric machine 3 has a rotor 3a and a stator 3b, and when the rotor 3a is rotationally driven by exhaust energy, AC power is generated in the stator 3b and a power converter 4, which will be described later, is generated.
Power is transmitted to the battery 5 via.

Furthermore, when power from the battery 5 via the power converter 4 is supplied to the stator 3b to drive the rotor 3a, the intake air is compressed by the operation of the compressor 2a, and the intake pipe 1
The engine 1 is supercharged via a. In addition, 1j is a boost pressure sensor, and compressor 2a
The supercharging pressure caused by the operation of is detected and transmitted to the electronic control unit 6.

FIG. 2 shows an example of an AC power conversion circuit in the power converter 4, which includes a rectifying and smoothing circuit 4a, a duty control circuit 4b, and a choke circuit 4C1. Then, the AC power from the rotating electrical machine 3 when the generator is operating is converted into DC by the rectifying and smoothing circuit 4a, and a predetermined control pulse signal from the electronic control device 6 is applied to the base input of the transistor Tr. The effective power value is controlled by using the passing current as a pulsating current. Thereafter, power at a desired voltage is supplied to the load via the choke channel.

In addition to the above conversion circuit, the power converter 4 also includes a battery 5.
It also has a converter circuit that converts DC power from the source into AC of a predetermined frequency to drive the rotating electric machine 3, and an inverter circuit that converts DC power to AC power whose frequency can be adjusted freely.The frequency control of the inverter circuit is electronically controlled. It is controlled by commands from the control device 6.

Therefore, AC power from the rotating electrical machine 3 when the generator is operating is converted to direct current by the rectifying and smoothing circuit, and controlled to power suitable for battery charging by the converter circuit and duty control circuit. , DC power from the battery 5 is converted into AC power of a predetermined voltage and frequency by the operation of a converter circuit or an inverter circuit, and is supplied to the stator 3b, which assists the supercharging operation of a turbocharger driven by exhaust energy. It is something.

3c shown in Fig. 1 is an AC voltmeter that measures the terminal voltage of the stator 3b of the rotating electric machine 3, and 4d is a DC voltmeter that measures the DC terminal voltage of the power converter 4.The measured voltages are controlled electronically. Send to device 6.

The electronic control unit 6 is composed of a microcomputer, and is a central processing unit that inputs the operating status of the engine 1 and signals from the voltmeter, performs arithmetic processing, counts the number of control operations, etc., and controls the operating status of the engine according to the depression of the accelerator pedal. Various memory devices that store maps related to required boost pressure and control programs for the operation of rotating electric machines, and input/output devices that receive input from various sensors and issue control instructions to actuators, power converters, etc. etc. Note that 3d is a rotor position sensor that detects the magnetic pole position of the rotor 3a during rotation and is used to control the phase of the power supplied to the rotating electric machine 3.

FIG. 3 is a process flow diagram showing an example of the operation of this embodiment, and the operation will be explained with reference to FIG.

First, in Step 1, check the engine speed using the signal from the rotation sensor 1e, and if it is determined to be faster than the idle speed (for example, 800 RPM or more), check whether the clutch is disconnected (Step 2), and if the clutch is connected, accelerate the engine. Detect the position (step 3). If the accelerator position is partially depressed (step 4), the engine speed (step 5), current boost pressure PB2 (step 6), and accelerator equivalent boost pressure FBI are detected from each sensor. The difference between the equivalent boost pressure FBI and the current boost pressure PB2 is calculated (step 8). When it is determined that the difference between the equivalent boost pressure FBI and the current boost pressure PB2 is larger than the predetermined value A, this means that assistance by electric motor operation is required.
Calculate the power to be supplied to the rotating electric machine 3 necessary for acceleration (Step 10), and detect the turbine rotation speed (Step 11).
Determine the duty control required to increase the voltage of the supplied power (Stellar) 12). Then, the power converter 4 is activated (
In step 13), the phase of the supplied power is determined by the rotor position sensor, and the inverter provided in the power converter 4 is operated (step 14) to increase the speed of the motor-operated rotating electric machine. Next, let's detect the boost pressure PB Step 15)
, controls the fuel actuator 7 to control the fuel increase corresponding to the increase in boost pressure (step 16), and compares the boost pressure PB with the equivalent boost pressure PH1 (step 17), and determines that PB>equivalent boost pressure If it is FBI, the accelerator position is detected by the accelerator sensor 1c (step 18), and the engine rotation speed is detected (step 19). Since PB has now exceeded P81, whether or not the engine torque requires assistance from the electric motor is determined based on the load range stored therein. Step 2
At 0, it is checked whether or not the electric motor needs to be activated. If the electric motor is in operation, the process goes to step 45, and if not, the process goes to step 34 for 6 lines.

Incidentally, when it is determined in step 9 that the difference between the equivalent boost pressure FBI and the current boost pressure PB2 is smaller than the predetermined value A, the process directly proceeds to step 17 described above.

When it is determined in step 1 that the engine speed is 80 ORPM or less, the process moves to step 21. 1. The actuator 1h and the bypass valve 1g are operated to accelerate the flow rate of exhaust gas and increase the rotation speed of the turbocharger. Bypass control is performed.

Next, step 2 is to measure the voltage V generated by the rotating electric machine 3.
2), the magnitude is compared with the battery voltage vb (step 23). As a result, when v<vb, the boost duty of the high frequency coil is controlled (step 24), and the battery is charged after the generated voltage ■ is boosted above the battery voltage vb.

In addition, when the accelerator is fully depressed in step 4, the process moves to step 25, where the rotation sensor 1e detects the engine rotation speed, and the maximum driving force (maximum boost pressure) of the engine is searched by the CPU (step 26). ,
The rotational speed of the turbine of the turbocharger and the current boost pressure are detected (step 27, 28) and compared with the maximum boost pressure (step 29). If the boost pressure is still lower than the maximum boost pressure, duty control necessary to increase the voltage for driving the rotating electric machine is determined. Here, the power converter is activated (step 30), and the rotor position sensor 3d is
The phase of the supplied power is determined based on the signal from the inverter, and the inverter is operated (step 31). Next, the boost pressure after the rotating electric machine is driven is detected (step 32), the amount of fuel is increased in accordance with the increase (step 33), and the process proceeds to step 17. Note that when it is determined in step 29 that the boost pressure has become greater than the maximum boost pressure, the process similarly moves to step 17.

When it is determined in step 20 that the electric motor is not being driven, the process proceeds to step 34, where it is checked whether the supercharging operation or the generator operation is performed according to the load zone stored in the storage device (step 35), and when it is determined that the motor is operating as a supercharging operation. turns off the power generation circuit (step 36). When it is determined that the generator is operating, the generated voltage is measured (step 37), and the generated voltage V and the battery voltage vb (JX) are compared (step 38). If V>vb, the duty control of the power converter is performed (step 39), the battery charging circuit is turned on, and the battery is charged (step 40). Then, check the charging state (step 41), and if charging is in progress, return to step 2 of the start. When charging is not in progress, a failure signal is generated to notify the failure (step 42). Naori>
If not, step 43: Measure the generated voltage.
), the power converter 4 performs duty control (step 44), and then the process moves to step 40 described above.

Next, FIG. 3 (part 3) is a process flow diagram for constantly correcting and controlling the relationship between boost pressure and fuel so that a normal air/fuel ratio is maintained, and the process is performed in six lines from step 20.

That is, when it is determined in step 20 that the electric motor is operating, the process moves to step 45 shown in FIG. 3 (part 3), and the boost pressure Pc corresponding to the accelerator pedal position detected in step 18 is calculated.

On the other hand, the fuel flow rate is measured by the load sensor 1d (step 46), and the fuel equivalent boost pressure P is determined by this fuel flow rate.
Calculate fc (step 47). Then, Pc and Pf
Compare the size with c Step 48), Pc > P
If fc, it is necessary to increase the fuel, so the fuel actuator tough is controlled in the direction of increase to correct the flow rate (step 49). The corrected boost pressure (FadjI+ΔP) that should increase due to this correction is calculated in step 50. Next, in step 51, the magnitude of Pc and FadJl is compared, and if Pc<Fadjl, the correction is completed and the process goes to step 55 for eight lines. Note that if Pc≧FadJ1 in step 51, then Pc<F, ad
Steps 48-50 are repeated until J1 is reached.

On the other hand, if Pc<Pfc in step 48, the process proceeds to step 52, in which the fuel actuator tough is driven in the direction of decrease to correct the flow rate (step 53), and the boost pressure equivalent to decrease (Fadj2-ΔP) is calculated. . Then, compare the size of Pc and Fadj2 (Step 54)
, Pc <Fadj 2, the correction is completed and the process moves to step 55. Note that if Pc≧FadJ2, step 52 is performed until Pc<Fadj2.
-54 are repeated. As a result of the above, the ratio of air and fuel supplied to the engine is corrected so that the normal air-fuel ratio is always maintained.

Next, go to step 55, line 0, to calculate the driving power to assist the supercharging operation by driving the rotating electric machine, to detect the turbine rotation speed (step 56), and to determine the duty required for voltage increase (step 57). , operate the inverter to adjust the phase and voltage of the supplied power (step 58).
. Next, the boost pressure is detected (step 59), and the amount of fuel is increased in accordance with the increase (step 60).
Control flow returns to step 2.

FIG. 4 is a process flow diagram showing another example of the operation of this embodiment, and the operation will be explained with reference to FIG.

Steps 1 to 20 are the same flow as in the previous embodiment.

Next, the process moves to step 21 to calculate the power supplied to drive the electric motor and detect the turbine rotation speed.Step 22
), the duty at the power converter necessary for increasing the power is determined (step 23), and the inverter is operated to adjust the phase and voltage of the supplied power (step 24). Next, the boost pressure PB2 after assistance is detected (step 25), and compared with the accelerator equivalent boost pressure PB1, it is determined in step 21i.
), if PBI>PB2, control the fuel flow rate and (
Step 27), return to step 15. On the contrary, P
If 81<PB2, the process moves to step 54, which will be described later.

In step 1, the engine speed is 80 ORPM.
If it is determined that the following is true, proceed to step 28,
The steps 28 to 31 are the steps 21 to 2 in FIG.
Same as 4.

Further, when the accelerator is fully depressed in step 4, the process moves to step 33, where the engine rotational speed is detected, and the maximum driving force (maximum boost pressure) of the engine is detected by the electronic control device.Step 34 ), step 35 to detect the rotation speed of the turbocharger turbine.
), the current boost pressure PA is detected (step 36), and compared with the maximum boost pressure (step 37). If it is still less than the maximum boost pressure, the electric! Jl] Determine the duty control required to increase the power supply for machine drive. Then, the power converter is activated (step 38), the phase is determined based on the signal from the rotational position sensor, and the inverter is activated (step 39). The boost pressure PB increased in step 40 is detected and compared with the boost pressure PA before increasing (step 41). If PB>PA, the fuel flow rate is controlled (step 42), and step 17
to move to. On the other hand, if PB<PA, the process moves to step 54, which will be described later.

If it is determined in step 20 that the motor is not being driven, the process goes to step 43 for 8 lines, and the steps up to step 43 or 653 are the same as steps 34 to 44 in FIG. 3, and the state of charge is checked in step 50. Y, Y
If ES, the process returns to the starting step 2, and if No, a failure signal is generated to notify the failure (step 51).

Next, steps 54 to 61 are a control flow for diagnosing a failure of a turbine blade, especially when assisted by electric motor operation to increase the boost pressure, and the flow shifts from step 26 or step 41 to step 54.

First, in step 54, the required boost pressure increase value ΔP (i.e., P Bl-P B2, or PB-PA) is determined.
Step 55)
The electric current supplied to the rotating electric machine is detected (step 56) and the electric power value is calculated. This power value and boost pressure increase value ΔP
Step 57)
When the pressurizing work amount is smaller than the calculated power value, the average value for several seconds is further detected (step 58). Again, compare the magnitude of the electric power value and the pressurizing work (step 59), and if the electric power value is greater than the pressurizing work, it is determined that there is a failure in the turbine blade, and a failure signal is generated (step 60), and the electric switch is turned off. (step 61). Step 57 or
If the electric power value is equal to the pressurizing work amount in step 59, it is determined that there is no failure, and the control flow returns to the initial step 2.

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

(Effects of the Invention) According to the present invention, the intake boost pressure required by the internal combustion engine is determined according to the amount of depression of the accelerator pedal, and
Calculate the appropriate fuel supply amount corresponding to this boost pressure,
Since the intake air supercharging operation and the fuel flow rate are each corrected, an air-fuel ratio corresponding to the operating condition can always be obtained, and the required engine output can be obtained.

Further, according to the present invention, when assisting the intake air supercharging operation, the power supplied to the rotating electric machine operated by the motor and the amount of work thereof are checked, so that if there is an abnormality in this, it is judged as a failure and the abnormality can be diagnosed. There is also.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram showing an embodiment of a control device for a turbocharger with a rotating electric machine according to the present invention, FIG. 2 is a circuit diagram showing an example of a power converter used in this embodiment, and FIGS. The figure is a processing flow diagram showing the operation of this embodiment. 1...;Engine, IC...accelerator sensor, 1d...
...Load sensor, 1e... Rotation sensor, 1j... Boost pressure sensor, 2... Turbocharger, 3...
Rotating electric machine, 4... Power converter, 5... Battery, 6
...Electronic control device, 7...Fuel actuator. Patent Applicant Isuy Jidosha Co., Ltd. Agent Patent Attorney Minoru Tsuji<a 4b 4C Figure 4 (3 of ¥) Thousand Motouri Neho Seisho (self-motivated) December 2, 1939? Mr. Kunio Ogawa, Commissioner of the Japanese Patent Office, 1. ,. 1. Indication of the case 1986 Patent Application No. 261240 2. Name of the invention Control device for turbocharger with rotating electric machine 3. Person making the amendment Relationship to the case Patent applicant address 6-22 Minami-Oi, Parts Yo-ku, Tokyo No. 10 Ji Dosha Name Name: Isuy Automobile Co., Ltd. Representative: Hiyama - 4, Male 4, Agent address: Lot 3-14 Kanda Ogawa-cho, Chiyoda-ku, Tokyo - Mansui Building Name (7840) Patent Attorney Minoru Tsuji 5. Date of amendment order (spontaneous) 6. Column ``Claims'' of the specification to be amended, Column 7 ``Detailed Description of the Invention'', Contents of amendment as per attached sheet (1) The scope of claims is amended as shown in the attached sheet. (2) Delete "Furthermore..." from page 3, line 18 of the specification to page 4, line 3 of the specification. (3) “Also...
There is also. ” divided by 41J. (4) “Also...” on page 20, lines 9 to 12 of the specification
・There is also. ” to be deleted. 2. Scope of the Claims A control device for a turbocharger with a rotating electrical machine connected to an exhaust pipe of an internal combustion engine and having an electric generator on the rotating shaft of the mutual turbocharger, comprising means for detecting the amount of accelerator pedal depression of the internal combustion engine; Boosting means for boosting the pressure of supercharging air by driving an electric motor of the rotating electric machine in response to a signal from the detection means, and fuel control means for controlling the amount of fuel supplied corresponding to the boost pressure by the boosting means. A control device for a turbocharger with a rotating electric machine.

Claims (2)

[Claims] (1) In a control device for a turbocharger with a rotating electrical machine, which is connected to an exhaust pipe of an internal combustion engine and which supercharges intake air using exhaust energy, the turbocharger has an electric motor-generator on its rotating shaft, and the accelerator pedal depression amount of the internal combustion engine. a detecting means; a boosting means for boosting the pressure of supercharging air by driving an electric rotating machine in accordance with a signal from the detecting means; and a fuel control means for controlling an amount of fuel supplied corresponding to the supercharging pressure by the boosting means. A control device for a turbocharger with a rotating electrical machine, characterized by being provided with. (2) An abnormality detecting means is provided for detecting an abnormality in the turbocharger and diagnosing a failure when the electric motor of the rotating electric machine is driven by the boosting means to assist the supercharging operation. 1) A control device for a turbocharger with a rotating electric machine as described in item 1).