JPS6248931A - Turbocharger for internal combustion engine - Google Patents

Abstract

PURPOSE:To aim at the effective application of exhaust gas energy, by installing an alternator, making it operate and control as a motor-generator, in a turbine shaft. CONSTITUTION:A rotor 13 is set up in a shaft 7, and a stator core 15 to be opposed to this rotor 13 is provided with a stator coil 16 so that turning force is given to the rotor 13 by a DC current to be fed to the stator coil 16, making the shaft 7 rotate. When the shaft is driven by giving higher rotation than a periodic speed to be produced by an alternating current, since the rotor 13, the stator core 15 and the stator coil 16 constitute an induction motor, electromotive force is obtained out of the stator coil 16. The alternator consisting of the rotor 13, stator core 15 and stator coil 16 constitutes a motor-generator.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a turbocharger for an internal combustion engine.

(Prior art) As electric devices for vehicles using internal combustion engines, starting motors,
It is equipped with a number of other electrical devices, including igniters, horns, various lighting devices including headlamps, and indicating devices.
A secondary battery is used as a power source in the vehicle, and a generator driven by an internal combustion engine is mounted to charge the battery. Recently, new electrical devices have been developed, and the power consumption of vehicles is increasing due to their installation.

(Problems with the Prior Art) As mentioned above, in order to supply the power consumption, the battery is charged with electric power from a generator driven by the output of the internal combustion engine, but the energy of this electric power is used by the crank of the internal combustion engine. This is rotational energy input from the shaft to the generator via the V-belt, and a portion of the net output of the internal combustion engine is consumed by the electric device as electric power.

In addition, the above generator is limited in external dimensions due to the layout of the internal combustion engine, and the maximum power is, for example, 7.
The limit is about 00W-24V, and there is a fear that it will not be able to keep up with the power consumption of electrical devices, which is expected to increase in the future.

On the other hand, internal combustion engines are equipped with turbochargers that drive a turbine using the energy contained in exhaust gas, and use a compressor linked to the turbine to supercharge air into the cylinders to efficiently burn fuel. In this turbocharger, when the internal combustion engine is operating at low speed, the energy of the exhaust gas is low, so the supercharging pressure is low and the charging efficiency decreases, resulting in insufficient improvements in output and torque.

(Object of the Invention) In view of the above-mentioned conventional problems, the object of the present invention is to charge a battery without consuming the net output of the internal combustion engine, and to be able to cope with expected future power consumption. To provide a turbocharger for an internal combustion engine capable of improving torque at low speeds compared to conventional turbochargers.

(Summary of the Invention) In the present invention, in a turbocharger of an internal combustion engine,
An alternating current generator is provided on the turbine shaft of the turbocharger, the operation of which is controlled as an electric motor-generator based on a signal from the load detection means of the internal combustion engine and a signal from the rotation speed detection means of the internal combustion engine. A turbocharger for an internal combustion engine is provided.

Further, in the present invention, the alternating current machine is an induction alternating current machine using a squirrel-cage rotor, or a turbocharged internal combustion engine in which the alternating current machine uses a magnet rotor.

is also provided.

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

FIG. 1 is a configuration explanatory diagram showing one embodiment of a turbocharger for an internal combustion engine for realizing the present invention, and FIG. 2 is a block diagram showing the relationship between an internal combustion engine equipped with the turbocharger and a control device. It is a diagram.

In the figure, 1 is a turbocharger, 2 is a compressor housing, 3 is a turbine housing, and 4 is a center housing. At both ends of the center housing 4, there is a fixed bearing 5, and a floating ring that slides and rotates within the fixed bearing 5. A metal 6 is provided, and the floating metal 6 is connected to a turbine shaft (shaft).
Both ends of 7 are rotatably supported.

A compressor impeller 8 is attached to both ends of the shaft 7.
．． and a turbine impeller 9 are installed, respectively.
It is housed inside the compressor housing 2 and the turbine housing 3. The turbine impeller 9 rotates by receiving the energy of the exhaust gas sent to the scroll 10, rotates the compressor impeller 8 via the shaft 7, converts the pressure of air introduced from the intake pipe 11 into the diffuser 12, and generates internal combustion. It operates to feed pressure into the cylinders of the engine.

Further, in the vicinity of the center of the shaft 7, a plurality of conductors made of silicon steel plates laminated in the axial direction are passed through the periphery in the long sleeve direction, and short-circuited to the conductor plates 14 provided at both ends. A rotor 13 that constitutes a so-called squirrel cage rotor is provided.

A stator core 15 faces the rotor 13 and has a stator coil 16 wound to generate a predetermined rotating magnetic field.The alternating current supplied to the stator coil 16 gives the rotor 13 a rotational force and causes the shaft 7 to rotate. Let it rotate. Further, when the shaft 7 is driven by giving a high speed rotation faster than the periodic speed generated by the alternating current, the rotor 13.
Since the stator core 15 and the stator coil 16 constitute an induction generator, an electromotive force can be obtained from the stator coil 16. Therefore, the alternating current machine including the rotor 13, stator core 15, and stator coil 16 constitutes a motor-generator MG.

Figure 2 shows an internal combustion engine 2 equipped with the above turbocharger 1.
2 is a block diagram showing the relationship between 0 and the control device 21. In the figure, 22 is an exhaust manifold that communicates with the exhaust boat of the internal combustion engine 20, and the scroll 10 of the turbocharger 1 communicates with it. Reference numeral 23 denotes an intake manifold that guides the supercharging air that is force-fed by the compressor impeller 8 of the turbocharger 1 to the cylinders. A boost sensor 24 is provided which serves as a means for sending out and detecting the intake pressure of the internal combustion engine. 25 is an injection pump attached to the main body of the internal combustion engine 20;
A fuel flow sensor 2 serves as a means for detecting the fuel injection amount of the injection pump 25 and detecting the load on the internal combustion engine.
6 is provided to send a fuel flow signal to the control device 21.

Further, the crankcase 20a of the internal combustion engine 20 is provided with a rotation sensor 27 that detects the rotational speed of the crank and issues a signal to the control device 21.

The H control device 21 is a processor (CPU) that performs @ calculation processing.
and a read-only memory (RO) that stores programs for controlling the motor-generator MG and the inverter 29 described later.
It consists of an input port, an output port, a random access memory (RAM) that stores calculation results, and an address data bus (BUS) that connects these. A boost sensor 24, a fuel flow sensor 26, and a rotation sensor 27 are connected to the input boat, and receive detection signals from various sensors. In addition, the output boat has an electric
In addition to the generator MG, an inverter 29, a PWM controller 30. A regulator 31 is connected and outputs signals for controlling these.

The inverter 29 is supplied with DC power from the pantry 32 via the control device 21, converts the power into AC having a predetermined frequency, and supplies the power to the stator coil 16 to operate the motor-generator MG as a motor. Then, the shaft 7 is rotated to assist the supercharging operation of the compressor impeller 8 which is rotated by the exhaust energy. Note that the assisting operation is configured to be controlled by the output frequency of the inverter 29 in accordance with instructions from the control device 21.

The PWM controller 30 is a controller that receives the power generated when the motor-generator MG operates as a generator and controls the voltage of the power to a predetermined value. It is configured to match the voltage of the battery 32 and charge the battery 32.

FIG. 4 is a curve diagram shown by the fuel flow rate Q indicating the load of the internal combustion engine and the rotation speed N of the internal combustion engine, where A shows the no-load curve, B shows the full-load curve, and C shows the torque-up curve.
Therefore, in the case of 2, for example, fuel flow rate Qn and rotational speed Nn, Xn is between the no-load curve A and the full-load curve B, indicating that the internal combustion engine is in the partial load region.

Next, to explain the operation of this embodiment with such a configuration, the fuel flow rate supplied from the injection pump 25 to the internal combustion engine 20 is Qn, and the rotation speed of the internal combustion engine 20 is N.
In the case of n, the fuel flow sensor 26 sends a signal based on Qn, and the rotation sensor 27 sends a signal based on Nn to the control device 21. By receiving the signals based on Qn and Nn, the control device 21 detects from the memory stored in the ROM that the internal combustion engine 20 is in a partial load region between the no-load curve A and the full-load curve B. , electric generator MG
operates as a generator. Then, the electric power of the stator coil 16 generated by the rotation of the σ-tar 13 is sent to the PWM controller 30, and the electric power is controlled to a predetermined voltage value. Then, the voltage is matched to the voltage of the battery 32 by the regulator 31, and the battery is charged.

Next, the fuel flow rate supplied to the internal combustion engine 20 increases,
For example, in the case of a region between the full load curve B and the torque up curve C shown in FIG. 3, signals detected by the fuel flow sensor 26 and the rotation sensor 27 are sent to the control device 21. Then, the control device 21 controls the motor-generator MG to operate as an electric motor according to the control program for the motor-generator MG stored in the ROM, and also controls the motor-generator MG to operate as an electric motor.
Based on the detection signal of 4, the output frequency of the inverter 29 is controlled according to a stored control map, and power is sent to the stator coil 16, thereby assisting the supercharging operation of the compensator impeller 8 to obtain the optimum boost pressure. The electric motor-generator MG is operated as an electric motor as shown in FIG. Although the energy of the exhaust gas increases due to the above-described series of operations, and the driving force of the turbine impeller 9 also increases, the control device 21 performs control so that the boost pressure does not exceed a predetermined upper limit. That is, when the boost pressure reaches the upper limit, it can be operated as a single generator to absorb power. Further, even if the electric motor-generator MG is operated as an electric motor to assist the supercharging operation of the compressor impeller 8, if the boost pressure still does not reach a predetermined value, the inverter 29 is turned on so that the electric motor rotates even higher. Power is supplied to the stator coil 16 by controlling the output frequency.

FIG. 3 is a configuration explanatory diagram showing another embodiment of the turbocharger for an internal combustion engine according to the present invention, and the same parts as in FIG. 2 are given the same reference numerals, and the explanation thereof will be omitted.

In FIG. 3, reference numeral 17 denotes an axially long ring-shaped magnet rotor made of a magnetic material containing rare earth elements and having a large residual magnetism, and is disposed near the center of the shaft 7. Both end faces are fixed and held by high tensile strength metal disks 18, and the outer periphery of the magnet rotor 17 is wrapped and hardened with carbon fiber, making it strong even when subjected to centrifugal force and vibration due to ultra-high speed rotation. It has durability as a magnetic rotor.

19 is a stator core facing the magnet rotor 17;
It is induced by changes in magnetic flux caused by the rotation of the magnet rotor 17, and an electromotive force is generated in the stator coil 28.

Therefore, when the shaft 7 is rotated by an external force, the alternating current machine constituted by the magnet rotor 17, stator core 19, and stator coil 28 becomes a generator that generates alternating current from the stator coil 28 due to the change in magnetic flux caused by the rotation of the magnet rotor F. When AC power is supplied to the stator coil 28, the magnet rotor 17 becomes a rotating electric motor,
A motor-generator MG' is configured.

In the block diagram shown in FIG. 2, if the turbocharger 1' having the configuration shown in FIG. When it is in the partial load range between the full load curve B, the electric motor-generator MG' operates as a generator in response to a command from the control device 21, and the power is supplied via the PWM controller 30, the regulator 31, and the battery 32. Charge the battery 32.

Further, when the internal combustion engine 20 is in the region between the full load curve B and the torque up curve C, the electric power from the battery 32 is converted into a predetermined alternating current by the inverter 29 according to a command from the control device 21, and the electric power is converted into electric power. - Power is supplied to the generator MG' to assist in the supercharging operation of the compressor impeller 8, and to operate the turbocharger 1' to obtain the optimum boost pressure.

The present invention has been explained above using the above embodiments.

Various modifications are possible within the scope of the present invention, and these are not excluded from the scope of the present invention.

(Effects of the Invention) As explained in detail above, the present invention provides a turbocharger driven by exhaust gas energy with an electric generator, and controls the electric generator in the partial load range of the internal combustion engine. Since the device operates as a generator to charge the battery, exhaust gas energy can be used effectively and the net output of the internal combustion engine for charging can be prevented from being consumed. Furthermore, since a conventional generator is not used for charging, the space can be effectively used for other purposes, and the conventional V-belt and boot are no longer necessary.

Furthermore, by effectively utilizing exhaust gas energy to generate electricity, it is possible to meet expected future power consumption.

In addition, in the present invention, when the internal combustion engine rotates at low speed, the motor-generator is used as an electric motor to rotate to assist the supercharging operation, so that the low speed torque of the internal combustion engine is improved. Therefore, the low speed gear ratio of the transmission can be made smaller than before, and a compact transmission can be constructed.

[Brief explanation of the drawing]

FIG. 1 is a configuration explanatory diagram showing one embodiment of a turbocharger for realizing the present invention, FIG. 2 is a block diagram showing the relationship between an internal combustion engine using the turbocharger and a control device, and FIG. FIG. 4 is a diagram illustrating the structure of another embodiment of the turbocharger, and is a curve diagram showing the relationship between the fuel flow rate and the rotational speed, which indicates the load on the internal combustion engine. DESCRIPTION OF SYMBOLS 1... Turbocharger, 7... Turbine shaft (shaft), 13... Rotor, 16... Stator coil, 17... Magnet rotor, 26... Fuel flow sensor, 27... Rotation Sensor, MG, MG'...
・Electric power - generator. Patent applicant: IsuC Automobile Co., Ltd. (1 other person) Representative: Patent attorney: Minoru Tsuji ゝχ ``) Rei Kaede - ((Science 5Q wiped)

Claims (3)

[Claims] (1) In a turbocharger for an internal combustion engine, an alternating current machine whose operation is controlled as a motor-generator by a signal from a load detection means of the internal combustion engine and a signal from a rotation speed detection means of the internal combustion engine, A turbocharger for an internal combustion engine, characterized in that the turbocharger is provided on a turbine shaft of the turbocharger. (2) A turbocharger for an internal combustion engine according to claim (1), wherein the alternator is an induction alternator using a squirrel cage rotor. (3) A turbocharger for an internal combustion engine according to claim (1), wherein the alternating current machine is an alternating current rotating machine using a magnet rotor.