JPH0551047B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a turbocharger control device for an internal combustion engine.

(Prior Art) Vehicles using internal combustion engines are equipped with many other electrical devices, such as a starting motor, ignition device, horn, various lighting devices including headlamps, and indicating devices. As a power source, a battery from a secondary battery is used 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 replenish the power consumption, the battery is charged with power from a generator driven by the output of the internal combustion engine, but the energy of this power is used to power 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 limited to, for example, 700W-24V, which is in line with the expected increase in the power consumption of electrical equipment. There are also some serious concerns.

On the other hand, the energy of the exhaust gas is used to drive a turbine, and a compressor linked to this turbine supercharges air into the cylinder.
A turbocharger that burns fuel efficiently is installed and used in an internal combustion engine, and when the internal combustion engine is operating at low speed, the exhaust gas energy is low, so the boost pressure is low and the charging efficiency is reduced. Improvement in output and torque is insufficient.

(Object of the Invention) In view of the conventional problems as described above, the object of the present invention is to provide a battery that can be charged without consuming the net output of the internal combustion engine when charging the battery, and that is capable of charging the battery without consuming the net output of the internal combustion engine. To provide a turbocharger control device for an internal combustion engine capable of covering the power consumption in a vehicle without depending on the power generation of the engine and supercharging the internal combustion engine rotating at low speed under high load.

(Summary of the Invention) In order to achieve the above objects of the present invention, the present invention provides a turbine driven by exhaust gas energy of an internal combustion engine, and a compressor that supercharges intake air into a cylinder by driving the turbine. In the turbocharger for an internal combustion engine, an AC motor-generator is provided on the shaft of the turbine, and a load detection means for the internal combustion engine includes a fuel flow sensor for detecting the amount of fuel injected into the injector, and a rotation speed of the crankshaft. A revolution speed detection means for the internal combustion engine is provided, which is comprised of a rotation sensor, and a boost pressure detection means for the internal combustion engine is comprised of a boost sensor that detects the supply pressure provided in an intake manifold, and the load detection means and the revolution speed detection means are provided. When it is detected by the signal from the intake pressure detection means that the load condition and rotational speed of the internal combustion engine have fallen below a predetermined value and the boost pressure has fallen below a predetermined value, the AC motor-generator is operated as an electric motor. The load state and rotation speed of the internal combustion engine are higher than a predetermined value, and the boost pressure When it is detected that the AC motor-generator has increased above a predetermined value, the idling operating state of the internal combustion engine is detected by the second control means for operating the AC motor-generator as a generator, and the signal from the rotation speed detection means. and a third control means for controlling a battery to be charged by causing an AC motor-generator to act as a generator by driving a turbine by the exhaust gas of the internal combustion engine. I will provide a.

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

FIG. 1 is a block diagram of an embodiment for realizing the present invention, and FIG. 2 is an explanatory diagram showing the outline of a turbocharger.

In the figure, 1 is a turbocharger, 2 is a compressor housing, 3 is a turbine housing,
Reference numeral 4 denotes a center housing, and a fixed bearing 5 and a floating metal 6 that slides and rotates within the fixed bearing 5 are provided at both ends of the center portion of the center housing 4, and a shaft 7 is provided on the floating metal 6. Both ends are rotatably supported.

A compressor impeller 8 and a turbine impeller 9 are attached to both ends of the shaft 7, and are housed inside the compressor housing 2 and turbine housing 3, respectively. 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 the air introduced from the intake pipe 11 in the differential user 12, and generates internal combustion. It operates to feed pressure into the cylinders of the engine.

Further, near the center of the shaft 7, an axially long ring-shaped magnet rotor 13 containing a rare earth element is disposed and maintains a strong magnetic force.
Both end surfaces are fixed and held by high tensile strength metal discs 14, and the outer periphery of the magnet rotor 13 is wrapped and hardened with carbon fiber, making the magnet rotor strong even when subjected to centrifugal force and vibration due to ultra-high speed rotation. It has the durability of

A stator core 15 faces the magnet rotor 13 and induces an alternating current voltage in the stator coil 16 by rotation of the magnet rotor 13. Then, the magnet rotor 13, stator core 15, stator coil 1
The alternating current machine constituted by 6 constitutes a motor-generator MG.

FIG. 1 is a block diagram showing the relationship between an internal combustion engine 20 equipped with the above-mentioned turbocharger 1 and a control device 21. In the figure, 22 is an exhaust manifold communicating with the exhaust port of the internal combustion engine 20, and the scroll of the turbocharger 1 10 are connected. Reference numeral 23 denotes an intake manifold that guides supercharging air, which is force-fed by the compressor impeller 8 of the turbocharger 1, to the cylinder;
A boost sensor 24 is provided in the middle of the engine to detect the boost pressure of supercharging air and send a signal to the control device 21 to detect the intake pressure of the internal combustion engine. Reference numeral 25 denotes an injector attached to the main body of the internal combustion engine 20, and a fuel flow sensor 26 is provided, which serves as a means for detecting the fuel injection amount of the injector 25 and the load of the internal combustion engine. Send to.

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

The motor-generator MG is provided with a rotor position sensor 28 to prevent a decrease in the power factor of the electromotive force due to disturbance of the magnetic flux cutting the stator coil 16 during power generation when the magnet rotor 13 rotates at high speed. The rotor position sensor 28 is configured to send a detection signal to the control device 21 to control the phase of the electromotive force from the stator coil 16, thereby improving the power factor of power generation during high-speed rotation.

The control device 21 includes a processor (CPU) that performs arithmetic processing, a read-only memory (ROM) that stores programs for controlling the motor-generator MG and an inverter 29 (described later), input ports, output ports, calculation results, etc. It consists of a random access memory (RAM) that stores data, and an address data bus (BUS) that connects them. A boost sensor 24, a fuel flow sensor 26, a rotation sensor 27, a rotor position sensor 28, and the like are connected to the input port, and receive detection signals from various sensors. In addition, the output port has a motor-generator.
In addition to the MG, an inverter 29, a PWM controller 30, and a regulator 31 are connected, and signals for controlling these are output.

The inverter 29 is supplied with DC power from the battery 32 via the control device 21, converts the power into AC power, and operates 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. The assisting operation is configured to be controlled by the output frequency and output voltage of the inverter 29 according to instructions from the control device 21.

The PWM controller 30 is a controller that receives power generated when the motor-generator MG operates as a generator and controls the voltage of the power to a predetermined value.
1 to match the voltage of the battery 32 and charge the battery 32. In addition,
Reference numeral 33 indicates a malfunction lamp that indicates a malfunction state in charging the battery 32.

Figure 3 shows the fuel flow rate Q, which indicates the load on the internal combustion engine, and
2 is a curve diagram showing the rotational speed N of the internal combustion engine, in which A shows a no-load curve, B shows a full-load curve, and C shows a torque-up curve. Therefore, for example, in the case of 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, when the fuel flow rate supplied from the injector 25 to the internal combustion engine 20 is Qn and the rotation speed of the internal combustion engine 20 is Nn, the control device 21 The fuel flow sensor 26 sends out a signal based on Qn, and the rotation sensor 27 sends out a signal based on Nn. 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. The electric power of the stator coil 16 generated by the rotation of the magnet rotor 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. In addition, in the case of the above-mentioned generator, when the rotation of the magnet rotor 13 becomes extremely high speed,
The generated power has a high frequency, and the phase difference between voltage and current becomes large, resulting in a decrease in power factor, but the rotor position sensor 28 detects this phase difference, and the control device 2
1, the controller 21 controls the windings of the stator coil 16 to reduce the phase difference and improve the power factor.

Next, when the fuel flow rate supplied to the internal combustion engine 20 increases, for example in the region between the full load curve B and the torque up curve C shown in FIG. The respective detected signals are sent to the control device 21. The control device 21 then controls the electric motor-generator MG stored in the ROM.
The motor-generator MG is controlled to operate as an electric motor by the control program, and further, based on the detection signals of the fuel flow sensor 26, rotation sensor 27, and boost sensor 24, according to the stored control map. The output frequency and output voltage of the inverter 29 are controlled to send electric power to the stator coil 16 to assist the supercharging operation of the compressor impeller 8 and operate the motor-generator MG as an electric motor so as to obtain the optimum boost pressure. . Although the energy of the exhaust gas increases due to the series of operations described above, 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 generator to absorb power. Also, electric
Even if the 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 the predetermined value, the output frequency of the inverter 29 is changed so that the output of the electric motor further increases. Power is supplied to the stator coil 16 by controlling the output voltage.

FIG. 4 is a process flow diagram showing an example of the process of this embodiment. In the figure, first, the rotation sensor 27
Check the rotation speed by the signal (step a),
If the rotational speed is the predetermined idling rotational speed, the process proceeds to step b and the battery voltage is checked.
Here, if the voltage is normal or above a predetermined voltage value, there is no need to charge the battery, so the fuel flow rate is maintained at the reference value and the process returns to step a.

Next, if the battery voltage is below a predetermined voltage value in step b, the power from the motor-generator MG operating as a generator is controlled by the PWM controller 30 so that the charging current increases, and the regulator 31, the battery 32 is charged. And for this charging power, an electric motor-generator
Since the load on the MG increases, the fuel flow rate is increased to increase the energy of the exhaust gas (step c).

If the idling speed is above the predetermined idling speed in step a, the current consumption from the battery 32 is compared with the charging current (step d), and if the charging current is insufficient, the charging power from the motor-generator MG is The charging current is increased by controlling the PWM controller 30 or by increasing the fuel flow rate (step e). Then, it is checked whether the internal combustion engine is operating at a predetermined rotation speed based on the signal from the rotation sensor 27, and the load condition is checked based on the signal from the fuel flow sensor 26 (steps f and g), and if both are within the predetermined range, Proceed to step h.

In step h, control is performed according to the control map stored in the ROM of the control device 21 based on the signals from the fuel flow rate sensor 26, rotation sensor 27, and boost sensor 24, and between the full load curve B and the torque up curve C. In the case of the region, the output of the inverter 29 is calculated, and the inverter 29 is controlled to operate the electric motor-generator MG as an electric motor. Next, the detection signal from the boost sensor 24 is checked, and if the boost pressure is at a predetermined value, the integrated value of charging power is calculated, and the integrated power value is checked (steps i, j). This is an electric generator
While the MG is operating as an electric motor, the supply of charging current to the battery 32 is stopped, so the integrated power value is checked to monitor over-discharge of the battery 32, and if OK, return to the first step a.

If there is a malfunction in the electric power integrated value check, the malfunction lamp 33 is turned on and the process returns to step h, where the calculation for fine adjustment of the control map is performed and the electric power
Operate generator MG as a generator and battery 3
Perform 2 charging steps. Further, if the predetermined value is not obtained in the boost pressure check at step i, the process returns to step h and the calculation is performed again.

In this embodiment, a fuel flow sensor 26 is provided in the injector 25 as a means for detecting the load on the internal combustion engine, but depending on the accelerator pedal depression amount sensor and the type of internal combustion engine, for example, in the case of a diesel engine, The load may be detected by a position sensor for the fuel injection amount, or in the case of a gasoline engine, an opening sensor for the intake valve of the carburetor.

The present invention has been explained above using the above embodiments, but
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 in a partial load range of the internal combustion engine, the electric generator is controlled by a control device. Since the internal combustion engine is operated as a generator to charge the battery, exhaust gas energy can be used effectively and the net output of the internal combustion engine can be prevented from being consumed for charging. Furthermore, since a conventional generator for charging is not used, the space can be effectively used for other purposes, and the conventional V-belt and pulley are not required.

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 is operating at low speed, the control device can finely adjust the control map to operate the motor-generator as a motor. It is possible to rotate the engine and forcefully feed sufficient supercharging air to the internal combustion engine, thereby improving the output and torque of the internal combustion engine during low-speed operation.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment for realizing the present invention, Fig. 2 is a configuration explanatory diagram showing an outline of a turbocharger, Fig. 3 is a curve diagram showing the fuel flow rate and rotation speed of the internal combustion engine, FIG. 4 is a process flow diagram showing an example of the process of this embodiment. 1... Turbocharger, 7... Shaft, 8
...Complex impeller, 9...Turbine impeller, 20...Internal combustion engine, 24...Boost sensor, 21...Control device, 26...Fuel flow rate sensor, 27...Rotation sensor, MG...Electric power generator .

Claims (1)

[Claims] 1. In an internal combustion engine turbocharger equipped with a turbine driven by the exhaust gas energy of the internal combustion engine and a compressor that supercharges intake air into the cylinder by the drive of the turbine, an AC motor-generator is provided on the shaft of the turbine, An internal combustion engine load detection means consisting of a fuel flow sensor that detects the fuel injection amount of the injector, an internal combustion engine rotation speed detection means consisting of a rotation sensor that detects the rotation speed of the crankshaft, and a supply pressure installed in the intake manifold. The load state and rotation speed of the internal combustion engine are determined to a predetermined value based on the signals from the load detection means, the rotation speed detection means, and the intake pressure detection means. first control means for supercharging by operating the AC motor-generator as a motor when it is detected that the boost pressure has fallen below a predetermined value; the load detection means; and the rotation speed. When it is detected from the detection means and the signal from the intake pressure detection means that the load condition and rotational speed of the internal combustion engine are higher than a predetermined value and that the boost pressure has increased than a predetermined value, the AC motor-generator is activated. When the idling operating state of the internal combustion engine is detected by the signal from the second control means and the rotation speed detection means, the AC electric motor is operated by the turbine driven by the exhaust gas of the internal combustion engine.
A control device for a turbocharger for an internal combustion engine, comprising: third control means for controlling a generator to act as a generator to charge a battery.