JPH0650161A - Turbocharger system with rotary electric machine - Google Patents

Abstract

PURPOSE:To increase a supercharging atmospheric pressure through electric drive of a rotary electric machine even during high speed operation by generating a feed source, to the rotary electric machine mounted on a turbocharger, with the aid of a generator driven by means of engine torque. CONSTITUTION:The output of an AC generator 6 driven by an engine 2 is set to a value constantly higher than a reverse electromotive voltage during electric drive of the rotary electric machine 3 of a turbocharger 1. When a high load is applied on the engine 2 and the increase of a supercharging pressure is needed, power generated so that the rectified output of the AC generator 6 is overlapped with the voltage of a battery 4 is inputted to a power converter 5. The power is converted into a high voltage AC power of a given frequency, which is fed to the rotary electric machine 3, and a supercharging atmospheric pressure is increased through electric drive.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mounts a rotary electric machine on a turbocharger to collect exhaust energy, and particularly to increase boost pressure and output when a large engine is under heavy load. Regarding the charger system.

[0002]

2. Description of the Related Art In recent years, a turbocharger for increasing the boost pressure of the engine by utilizing the exhaust energy of the engine has been widely used. A rotary electric machine is attached to the turbine shaft of this type of turbocharger to keep the engine operating. In response to this, various attempts have been made, such as activating the turbocharger operation by electrically driving the rotating electric machine, or utilizing the power generation output for battery charging power by the power generation operation.

In a turbocharger for a large engine having a high boost pressure and a high output, a variable vane as shown in FIG. 4 is attached to the nozzle portion of the turbine to change the movement direction of exhaust gas to improve efficiency. Variable vane type turbochargers are known.

In such a variable vane type, the torque characteristic of the engine can be varied by changing its position, and the characteristic as shown by the curve diagram in FIG. 5 can be obtained. A is a throttle to minimize the area. When a rotation vector is given,
D is the case where the vane is most opened. Among these characteristics, B is the case where the torque is the largest and covers a wide rise in boost pressure. Therefore, it suffices to adjust the turbocharger to be in this state, fix the vane position, and increase the rotational speed of the turbocharger by the electric drive of the rotating electric machine to assist the supercharging operation at low speed rotation. Become.

[0005]

In the variable vane type turbocharger described above, the efficiency can be improved by changing the position of the vane. In this case, the temperature of the turbine rises and the vane deforms or expands. There is a possibility that a problem may occur due to.

Further, in order to fix the vanes and respond to a wide range of operation of the engine, the counter electromotive force of the rotating electric machine becomes large at high speed rotation, and sufficient driving cannot be performed unless high-voltage power is supplied, resulting in high voltage. However, there is a disadvantage that a transformer having a large step-up ratio is required to supply the power supply, and the cost increases.

The present invention has been made in view of the above problems, and an object thereof is to efficiently supply high-voltage electric power to a rotating electric machine to increase boost pressure and torque without using a variable vane when driving a turbine. It is to provide a turbocharger system with a rotating electric machine that attempts to increase

[0008]

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, and a supercharge operation is urged by electric drive of the rotary electric machine to generate an engine torque. In the turbocharger system with a rotating electric machine that raises the rotating electric machine, a generator that is driven by the torque of the engine and serves as a power source of the rotating electric machine is provided, and the output voltage of the generator is higher than the counter electromotive voltage when the rotating electric machine is electrically driven. A turbocharger system with a rotating electric machine set to a voltage is provided.

[0009]

[Function] Since the generator connected to the crankshaft of the engine is provided and the output voltage thereof is always set higher than the counter electromotive voltage when the rotating electric machine is electrically driven, a high output voltage is obtained and the rotating electric machine is driven even at high speed. The boost pressure can be increased.

[0010]

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

FIG. 1 is a block diagram showing a configuration of an embodiment of a turbocharger system with a rotating electric machine according to the present invention.

In the figure, 1 is a turbocharger, 2
Is a large engine, and the exhaust gas from the engine 2 is sent to the turbocharger 1 via the exhaust pipe 21, drives the turbine 11, and is discharged into the atmosphere. A rotary electric machine (TCG) 3 and a compressor 13 are attached to the turbine shaft 12, and the compressor 13 rotating by turbine torque compresses the sucked outside air and sends it to the engine 2 as supercharged air through an intake pipe 22. It is a thing. The gas flow for urging the turbine 11 is set in the flow path that can obtain the characteristic of B shown in FIG. 5 described above.

The rotating electric machine 3 has a rotor 31 made of a permanent magnet.
And a stator 32 having a winding to operate as an electric motor or a generator. For example, when DC power from a battery 4 or the like is converted into AC power by a power converter 5 having an inverter and supplied. The electric drive is used to urge the pneumatic operation of the compressor 13 to increase the boost pressure, or when the exhaust energy has a margin, it is operated to generate regenerative power.

Reference numeral 6 denotes an AC generator, which has a permanent magnet on its rotor, is connected to a crankshaft via a belt 62, and when driven by engine torque, outputs an AC output of a predetermined high voltage according to the number of revolutions. The output is converted into a direct current by the rectifier 61 having a smoothing circuit, and is connected so as to be superimposed on the terminal voltage of the battery 4. The curve diagram shown in FIG. 2 shows a comparison between the generated voltage of the AC generator 6 and the back electromotive force of the rotating electric machine 3, even if the respective rotation speeds change according to the operating state of the engine 2. The output of the AC generator 6 is always higher than a predetermined value.

Next, the operation of this embodiment constructed as described above will be explained. The engine 2 is operated, the turbine 11 is driven by the exhaust energy of the engine 2 to rotate the compressor 13, and the supercharged air is supplied by the pressurized air operation. Although it is pressure-fed to the engine 2, a desired sufficient supercharging pressure cannot be obtained at a high load, and thus it is necessary to assist the supercharging operation by electrically driving the rotating electric machine 3.

In this case, the rotational speed of the rotary electric machine 3 increases in accordance with the rotation of the engine 2 and the counter electromotive force of the rotary electric machine 3 becomes large, so that the power supply requires a high voltage, but in this embodiment, it is connected to the crankshaft. Since the AC generator 6 outputs a sufficiently high voltage electric power according to the engine rotation, the electric power obtained by superimposing the battery voltage on the direct current obtained by rectifying the electric power becomes sufficiently higher than the counter electromotive force as shown in FIG. Since this is converted into AC power through the inverter, the rotary electric machine 3 can always be electrically driven even on the high speed side of the engine.

Although the present invention has been described with reference to the above-described 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.

[0018]

According to the present invention as in the above embodiments,
The gas flow to the turbine of the turbocharger is set to a state where the torque is strongly energized, and the output voltage of the AC generator connected to the crankshaft is sufficiently higher than the counter electromotive force of the rotating electric machine. Since it is configured as described above, a high voltage is obtained by superimposing the output of the battery on the electric power that uses the AC generator as a power source, and even when the engine is at a high speed, the rotary electric machine can be electrically driven to obtain a high boost pressure, The effect that the engine output can be improved can be obtained.

Therefore, the inconvenience due to the use of the variable vanes and the high cost due to the step-up transformer as the power source for driving the rotating electric machine are eliminated.

[Brief description of drawings]

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

FIG. 2 is a chart showing a comparison between the output of the AC generator and the counter electromotive voltage of the rotating electric machine in the present embodiment.

FIG. 3 is an explanatory diagram of electric power supplied to the rotating electric machine according to the present embodiment.

FIG. 4 is an explanatory view of a variable vane turbine.

FIG. 5 is a characteristic diagram of engine torque by a turbocharger having a variable vane turbine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Turbocharger 2 ... Engine 3 ... Rotating electric machine 4 ... Battery 5 ... Power converter 6 ... Alternator 11 ... Turbine 13 ... Compressor 61 ... Rectifier

Claims (3)

[Claims] 1. A turbocharger system with a rotary electric machine, wherein a rotary electric machine is attached to a turbine shaft of a turbocharger, and the electric drive of the rotary electric machine urges a supercharging operation to increase engine torque, which is driven by the torque of the engine. In addition to providing a generator that will be the power source of the rotating electric machine,
A turbocharger system with a rotating electric machine, wherein an output voltage of the generator is set to a voltage higher than a counter electromotive voltage when the rotating electric machine is electrically driven. 2. The turbocharger system with rotating electric machine according to claim 1, wherein the output voltage of the generator is superimposed on the voltage of a battery mounted on the vehicle and is supplied to the rotating electric machine. 3. The turbocharger system with a rotating electric machine according to claim 1, wherein the gas flow for urging the turbine of the turbocharger is set in a flow path where a strong torque is obtained.