JP2004316558A - Control device of supercharger with electric motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smoothly perform supercharging while preventing excessive supercharging by a supercharger with an electric motor. <P>SOLUTION: This control device of the supercharger with the electric motor comprises: the supercharger 20 which is arranged on an intake passage 5 of an internal combustion engine 1 mounted to a vehicle and is driven by the electric motor 20a; boost pressure control means 16 and 21 for controlling a boost pressure by controlling the electric motor 20a; and a speed detection means for detecting a vehicle speed. When the vehicle speed detected by the speed detection means is equal to or less than a predetermined value, the boost pressure control means 16 and 21 control an electric power applied to the electric motor 20a to be equal to or less than a predetermined electric power. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a control device for a supercharger with a motor, which controls a supercharger with a motor disposed on an intake passage of an internal combustion engine mounted on a vehicle.
[0002]
[Prior art]
2. Description of the Related Art Attempts to provide a supercharger driven by an electric motor in an intake passage of an engine and obtain high output (or low fuel consumption) by supercharging by the supercharger have been known for some time. [Patent Document 1] also describes the internal combustion engine as described above. In the internal combustion engine described in Patent Literature 1, an electric motor (motor) is incorporated in a rotating shaft of a turbine / compressor of a turbo unit. In the internal combustion engine described in [Patent Literature 1], turbo lag after the start is eliminated by starting supercharging by a motor before the vehicle starts, and the transmission is set to neutral so that the transmission to the brake is prevented. This reduces the burden and prevents unexpected starting due to creep.
[0003]
[Patent Document 1]
JP-A-4-8640
[Problems to be solved by the invention]
In the internal combustion engine described in [Patent Document 1], as described above, supercharging is previously performed by an electric motor in order to eliminate the turbo lag when the vehicle is stopped. If supercharging is performed in advance using an electric motor, there is a possibility that supercharging may be excessive (hereinafter, referred to as supercharging). SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a control device for a supercharger with a motor capable of performing supercharging smoothly while preventing overcharging.
[0005]
[Means for Solving the Problems]
A control device for a supercharger with an electric motor according to claim 1 is provided on an intake passage of an internal combustion engine mounted on a vehicle and driven by the electric motor, and controls a supercharging pressure by controlling the electric motor. Pressure control means for controlling the speed of the vehicle, and speed detection means for detecting the speed of the vehicle. The supercharge pressure control means, when the vehicle speed detected by the speed detection means is a predetermined value or less, the electric motor Is limited to a predetermined power or less.
[0006]
According to a second aspect of the present invention, in the control device for a supercharger with an electric motor according to the first aspect, the supercharging pressure control means includes: It is characterized in that a target rotation speed of the motor is set in the region, and the electric power applied to the motor is determined so as to reach the set target rotation speed.
[0007]
According to a third aspect of the present invention, in the control device for a supercharger with an electric motor according to the first or second aspect, the supercharging pressure control means sets the target rotation speed of the electric motor lower as the EGR amount increases. It is characterized in that the electric power applied to the electric motor is determined so that the target rotation speed is obtained.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the control device of the present invention will be described below. FIG. 1 shows an engine 1 having a control device according to the present embodiment.
[0009]
The term “supercharging pressure” may be used as a term indicating a pressure difference with respect to the atmospheric pressure. On the other hand, the term "supercharging pressure" is sometimes used as a term indicating the absolute pressure in the intake pipe. In the following, when it is necessary to clearly explain the two, a description will be given so that the pointed point is clear. For example, when performing supercharging pressure control based on the output of a pressure sensor that detects the pressure in the intake pipe, if this pressure sensor is a sensor that detects a differential pressure with respect to atmospheric pressure, the supercharging pressure control will be performed as “the difference with respect to atmospheric pressure. It is easy to control based on “supercharging pressure”, and if the pressure sensor is a sensor that detects absolute pressure, supercharging pressure control is controlled based on “intake pressure as absolute pressure”. Is easy.
[0010]
The engine 1 described in the present embodiment is a multi-cylinder engine, but here only one cylinder is shown in FIG. 1 as a cross-sectional view. The engine 1 is of a type in which fuel is injected into a cylinder 3 by an injector 2. The engine 1 is a so-called lean burn engine, and is capable of stratified combustion. By supercharging a larger amount of intake air by the supercharger 20 and the turbocharger 11 by the electric motor 20a described later, not only high output but also low fuel consumption can be realized.
[0011]
The engine 1 can perform stratified combustion by injecting fuel into a depression formed on the upper surface of the piston 4 during the compression stroke, and can also perform normal homogeneous combustion by injection in the intake stroke. The interior of the cylinder 3 and the intake passage 5 are opened and closed by an intake valve 8. The exhaust gas after combustion is exhausted to the exhaust passage 6. The interior of the cylinder 3 and the exhaust passage 6 are opened and closed by an exhaust valve 9. On the intake passage 5, an air cleaner 10, an air flow meter 27, a supercharger 20, a turbo unit 11, an intercooler 12, a throttle valve 13, and the like are arranged from the upstream side.
[0012]
The air cleaner 10 is a filter that removes dust and dirt from the intake air. The air flow meter 27 of the present embodiment is of a hot wire type, and detects an intake air amount as a mass flow rate. The supercharger 20 is electrically driven by a built-in electric motor (motor) 20a. The compressor wheel is directly connected to the output shaft of the motor 20a. The motor 20 a of the supercharger 20 is connected to the battery 22 via the controller 21. The controller 21 controls driving of the motor 20a by controlling power supplied to the motor 20a. The rotation speed of the motor 20a (that is, the rotation speed of the compressor wheel) can be detected by the controller 21.
[0013]
A bypass 24 is provided to bypass the upstream side and the downstream side of the supercharger 20. A valve 25 for adjusting the amount of intake air passing through the bypass passage 24 is provided on the bypass passage 24. The valve 25 is electrically driven and arbitrarily regulates the air flow through the bypass 24. When the supercharger 20 is not operating, the supercharger 20 acts as intake resistance, so that the bypass passage 24 is opened by the valve 25 to prevent the supercharger 20 from becoming intake resistance. I do. Conversely, when the supercharger 20 is operating, the bypass passage 24 is shut off by the valve 25 in order to prevent the intake air supercharged by the supercharger 20 from flowing back through the bypass passage 24.
[0014]
The turbo unit 11 is disposed between the intake passage 5 and the exhaust passage 6 to perform supercharging. That is, in the engine 1 of the present embodiment, supercharging can be performed by the supercharger 20 and the turbo unit 11 arranged in series. The turbo unit 11 has a variable nozzle mechanism 11a as a variable geometry mechanism. The variable nozzle mechanism 11a is controlled by an ECU 16 described later. Downstream of the turbo unit 11, an air-cooled intercooler 12 that lowers the temperature of intake air whose temperature has increased due to pressure increase due to supercharging of the supercharger 20 and the turbo unit 11 is arranged. The intercooler 12 lowers the temperature of the intake air to improve the charging efficiency.
[0015]
Downstream of the intercooler 12, a throttle valve 13 for adjusting the amount of intake air is arranged. The throttle valve 13 of the present embodiment is a so-called electronically-controlled throttle valve. The operation amount of an accelerator pedal 14 is detected by an accelerator positioning sensor 15, and the ECU 16 controls the throttle valve 13 based on the detection result and other information amounts. Is determined. The throttle valve 13 is opened and closed by a throttle motor 17 provided in association therewith. In addition to the throttle valve 13, a throttle positioning sensor 18 for detecting the opening degree is also provided.
[0016]
A pressure sensor 19 for detecting the pressure (supercharging pressure / intake pressure) in the intake passage 5 is also provided downstream of the throttle valve 13. These sensors 15, 18, 19, 27 are connected to the ECU 16 and send the detection results to the ECU 16. The ECU 16 is an electronic control unit including a CPU, a ROM, a RAM, and the like. The injector 2, the spark plug 7, the valve 25, the air flow meter 27, the controller 21, the battery 22, and the like are connected to the ECU 16, and these are controlled by a signal from the ECU 16, and the state thereof (the state of the battery 22). (If any) the state of charge is monitored.
[0017]
The motor 20a of the supercharger 20 described above is also connected to the ECU 16 via the controller 21, and is controlled by the ECU 16 and the controller 21. Since the ECU 16 and the controller 21 can control the supercharging pressure by controlling the electric motor 20a, they function as supercharging pressure control means here. In the present embodiment, the supercharging pressure control is performed using the intake air amount as the operating state of the engine 1. Since the intake air amount is detected by the air flow meter 27, the air flow meter functions as operating state detection means here. Further, as will be described in detail later, the supercharging pressure upper limit at which supercharging is possible is set by the ECU 16 based on the detected intake air amount. That is, in the present embodiment, the ECU 16 also functions as an upper limit setting unit.
[0018]
On the other hand, on the exhaust passage 6, an exhaust purification catalyst 23 for purifying exhaust gas is mounted downstream of the turbo unit 11. A crank positioning sensor 26 that detects the rotational position of the crankshaft is attached near the crankshaft of the engine 1. The crank positioning sensor 26 can also detect the engine speed from the position of the crank position.
[0019]
An EGR (Exhaust Gas Recirculation) passage 28 for recirculating exhaust gas from the exhaust passage 6 (upstream of the turbo unit 11) to the intake passage 5 (surge tank formed downstream of the pressure sensor 19) is provided. Is established. An EGR valve 29 for adjusting an exhaust gas recirculation amount (EGR amount) is mounted on the EGR passage 28. The opening degree (DUTY ratio) of the EGR valve 25 is also controlled by the ECU 16 described above. Although not shown, an EGR cooler that cools the EGR gas using the cooling water of the engine 1 is provided between the EGR valve 29 and the surge tank in the intake passage 5.
[0020]
In the present embodiment, the power applied to the motor 20a is limited to a predetermined value or less when the vehicle speed is equal to or less than a predetermined value, particularly when the vehicle is stopped or running at a low speed. By doing so, it is possible to prevent turbocharging while eliminating turbo lag after the vehicle has started. Here, the target rotation speed of the motor 20a is set in a rotation speed region where the rate of change of the supercharging pressure with respect to the rotation speed of the motor 20a is equal to or less than a predetermined value, and the power applied to the motor 20a is determined so as to reach the target rotation speed. Is done. At this time, the target rotation speed of the motor 20a is set lower as the EGR amount increases.
[0021]
2 and 3 show flowcharts of this control. First, it is determined whether a condition for performing supercharging using the supercharger 20 (motor 20a) is satisfied (step 200). Here, the start / maintenance condition is a condition that can be determined to be a situation that requires an increase in output or a situation in which an increase in output is predicted. The start / maintenance condition is a determination condition for starting if the supercharging by the motor 20a has not been started, or a determination condition for maintaining the supercharging by the motor 20a as it is if it has already been started. If step 200 is denied, supercharging using the supercharger 20 is not performed, and the process exits the flowcharts of FIGS. 2 and 3.
[0022]
On the other hand, if step 200 is affirmed and it is determined that supercharging by the supercharger 20 (motor 20a) is necessary, first, the target supercharging pressure Pt and the target supercharging pressure Pt are determined based on the accelerator opening, the engine speed, and the engine load. The target fresh air amount Gat is determined by the ECU 16 (step 205). The accelerator opening is detected by an accelerator positioning sensor 15. The engine speed is detected by a crank positioning sensor 26. The engine load is calculated based on the intake air amount detected by the air flow meter 27 and the throttle opening detected by the throttle positioning sensor 18.
[0023]
The gas supplied to the cylinder 3 is composed of air (fresh air) newly sucked from the atmosphere and exhaust gas circulated by the EGR mechanism. The target fresh air amount Gat is a target of this fresh air amount. In order for the engine 1 to obtain a certain output, the amount of air required for its combustion is required as fresh air. Next, the vehicle speed V is detected (step 210). The vehicle speed V is calculated (detected) by the ECU 16 based on the detection result of a vehicle speed sensor (not shown) attached to each wheel. Then, it is determined whether or not the detected vehicle speed V exceeds a predetermined value (step 215).
[0024]
If the vehicle speed V exceeds the predetermined value, the target rotation speed of the motor 20a is determined based on the target supercharging pressure Pt and the target fresh air amount Gat determined in Step 205 as usual (Step 220). On the other hand, if the vehicle speed V is equal to or less than the predetermined value, the target rotation speed is limited and the target rotation speed of the motor 20a is determined (step 220). As will be described later, limiting the target rotation speed of the motor 20a limits the amount of power applied to the motor 20a (restricts the power to less than or equal to a predetermined power).
[0025]
In this case, the upper limit of the rotational speed is determined, and the target rotational speed may be determined based on the target supercharging pressure Pt and the target fresh air amount Gat within a range not exceeding the upper limit. If the upper limit is exceeded, a predetermined fixed target rotation speed may be used. At this time, the target rotation speed is limited to a region where the boost pressure sensitivity is low, as shown in FIG. The graph of FIG. 4 shows the relationship between the number of revolutions of the compressor wheel (that is, equal to the number of revolutions of the motor 20a) and the supercharging pressure. In contrast, the boost pressure rises exponentially.
[0026]
For this reason, on the side where the compressor rotation speed is low, there is a region where the change in the supercharging pressure is slow with respect to the change in the compressor rotation speed. The above-mentioned low boost pressure sensitivity means that the change rate of the boost pressure with respect to the rotation speed of the motor 20a (here, equal to the rotation speed of the compressor wheel) is low in this region. That is, limiting the target rotation speed of the motor 20a to a range where the change in the supercharging pressure is small with respect to the change in the rotation speed of the motor 20a means that the power applied to the motor 20a is equal to or less than the predetermined power.
[0027]
Thereafter, it is further determined whether or not the region is in a region where exhaust gas recirculation by EGR is possible (step 230). If there is not enough room to inhale the target fresh air amount Gat described above, the EGR will reduce the fresh air amount, so that exhaust gas recirculation by EGR cannot be performed. However, when exhaust gas recirculation by EGR is possible, exhaust gas recirculation by EGR is performed to improve exhaust emission performance and fuel efficiency. If exhaust gas recirculation by EGR is possible, that is, if step 230 is affirmative, the amount of electric power applied to the motor 20a is determined based on the above-described target rotation speed, taking into account the amount of EGR (step S230). 235).
[0028]
Note that the EGR amount is calculated by another routine. In this embodiment, at this time, the target rotation speed determined in step 220 or step 225 is corrected (set) so that the target rotation speed of the motor 20a decreases as the EGR amount increases. The amount of power to be applied to the motor 20a is determined based on the target rotation speed corrected in consideration of the EGR amount. When the amount of applied electric power is determined, the motor 20a is driven based on the determined amount of electric power to perform supercharging by the supercharger 20 (step 240). After step 240, the actual new air amount Ga is detected by the air flow meter 27 (step 245), and it is determined whether or not the detected new air amount Ga has reached the target new air amount Gat (step 250). .
[0029]
If the fresh air amount Ga has not reached the target fresh air amount Gat, that is, if step 250 is denied, the EGR valve 29 is controlled to reduce the exhaust gas recirculation amount due to EGR and the opening degree of the variable nozzle mechanism 11a. (Step 255). By doing so, the supercharging by the turbo unit 11 is promoted and the supercharging is delayed in order to increase the fresh air amount and eliminate a turbo lag caused by a small fresh air amount (a large EGR amount). To reduce. On the other hand, when the new air amount Ga has reached the target new air amount Gat, that is, when the determination in step 250 is affirmative, the EGR valve 29 is controlled to increase the exhaust gas recirculation amount by EGR, and the variable nozzle mechanism 11a The opening is opened (step 260). By doing so, the fresh air amount can be reduced, the EGR amount can be secured, and fuel efficiency can be improved.
[0030]
If step 230 is denied, that is, if exhaust gas recirculation by EGR cannot be performed, the amount of electric power to be applied to the motor 20a is determined based on the target rotation speed described above (step 265), and the determined application The supercharger 20 performs supercharging by driving the motor 20a based on the electric energy (step 270). After step 255, step 260 or step 270, the actual supercharging pressure P is detected by the pressure sensor 19 (step 275), and it is determined whether or not the detected supercharging pressure P has reached the above-described target supercharging pressure Pt. A determination is made (step 280).
[0031]
If the supercharging pressure P has reached the target supercharging pressure Pt, that is, if the step 280 is affirmative, the current state further falls within a region where the target supercharging pressure Pt can be achieved without driving the motor 20a. It is determined whether or not there is (step 285). If the current state is within the range where the target supercharging pressure Pt can be achieved without driving the motor 20a, the driving of the motor 20a is stopped and the supercharging by the supercharger 20 is ended (step 290).
[0032]
On the other hand, even if the supercharging pressure P has not reached the target supercharging pressure Pt (step 280 is negative), or if the supercharging pressure P has reached the target supercharging pressure Pt, the current state is the motor. If the target supercharging pressure Pt is within the range where the target supercharging pressure Pt can be achieved unless the 20a is driven (step 285 is negative), it is determined whether or not the condition for stopping the supercharging by the supercharger 20 is satisfied. A determination is made (step 295). If the stop condition is satisfied, the driving of the motor 20a is stopped, and the supercharging by the supercharger 20 is completed (step 290). If the stop condition is not satisfied, the process exits the flowcharts of FIGS. 2 and 3 while the supercharging by the supercharger 20 is maintained, and is executed again from step 200.
[0033]
As described above, when the vehicle speed V is equal to or lower than the predetermined value, the rotation speed of the motor 20a is limited (that is, the applied power is limited), so that a high boost pressure is required when the vehicle speed V is equal to or lower than the predetermined value. When it is not a situation, it is possible to effectively prevent the supercharging pressure from becoming too high (supercharging).
[0034]
In the above-described embodiment, the rotation speed of the motor 20a is limited to the above-described region where the boost pressure sensitivity is low (that is, the applied power is limited). The target pressure of the motor 20a is set in a region where the supercharging pressure does not change significantly with respect to the change in the rotation speed of the motor 20a, that is, the vehicle behavior does not change significantly. By determining the power to be applied to the power supply 20a, it is possible to prevent the supercharging and prevent the vehicle behavior from being adversely affected.
[0035]
Further, in the above-described embodiment, the target rotation speed of the motor 20a is set to decrease as the EGR amount increases. By doing so, when the EGR amount is large, the supercharging effect is limited to ensure the effect of the EGR, and the exhaust emission performance can be further improved.
[0036]
In the above-described embodiment, the power applied to the motor 20a is limited to the predetermined power or less even when the vehicle is running, such as when the vehicle is running at a low speed. However, the power applied to the motor 20a is determined only when it is determined that the vehicle is stopped. The power may be limited to a predetermined power or less. In this case, when the vehicle is stopped, supercharging by the supercharger 20 is started in advance in order to improve acceleration after starting (pre-assist). In this case, the applied power to the motor 20a is limited to a predetermined power or less in order to prevent the occurrence of supercharging. FIG. 5 shows a flowchart in this case.
[0037]
First, it is determined whether the pre-assist start condition described above is satisfied (step 500). The pre-assist start condition is a condition for assuming that the vehicle is stopped but is likely to start immediately. For example, one of the pre-assist conditions is when the vehicle is stopped and a transition is made from a state where the brake pedal is depressed to a state where the brake pedal is not depressed. The pre-assist condition may be a case where the gear is shifted from the neutral state to the connected state (forward) while the vehicle is stopped. Here, it is determined here that the vehicle is stopped (that is, the vehicle speed can be regarded as 0). If step 500 is denied, the process exits the flowchart of FIG.
[0038]
On the other hand, if step 500 is affirmed and the pre-assist condition is satisfied, the target rotation speed of the motor 20a is determined (step 505). This target rotation speed is limited to the above-described region where the supercharging sensitivity is low in FIG. Even within this region, the rotation speed may be determined as a predetermined fixed target rotation speed, or may be determined according to the operating state of the engine 1. When the target rotation speed is determined, it is determined whether or not the engine is in an EGR-enabled region (step 510). This step itself is the same as step 230 described above.
[0039]
If step 510 is affirmed, that is, if exhaust gas recirculation by EGR is possible and executed, the target rotation speed determined in step 505 is corrected to a low rotation side (step 515). In the present embodiment, at this time, the target rotation speed is corrected so that the target rotation speed of the motor 20a decreases as the EGR amount increases. Then, the amount of electric power applied to the motor 20a is determined based on the corrected target rotation speed (step 520). On the other hand, if step 510 is denied, that is, if exhaust gas recirculation by EGR is not performed, the amount of electric power applied to the motor 20a is determined based on the target rotation speed determined in step 505 (step 520).
[0040]
By doing so, the supercharging at the time of pre-assist can be suppressed by limiting the rotation speed of the motor 20a when the vehicle is stopped (the vehicle speed is equal to or less than the predetermined value 0). In particular, by limiting the rotation speed of the motor 20a to within the low supercharging sensitivity region in FIG. 4, it is possible to reliably prevent the adverse effect of the supercharging while improving the vehicle kinetic performance after the vehicle starts. Further, the exhaust emission performance can be further improved by lowering the target rotation speed of the motor 20a as the EGR amount increases.
[0041]
Note that the present invention is not limited to the embodiment described above. For example, in the embodiment shown in FIG. 1 described above, the turbocharger 20 with the motor 20a is provided upstream of the turbo unit 11 separately from the turbo unit 11. However, the present invention can be applied to a supercharger with a motor (motor), and as shown in FIG. 6, a turbo unit 11 having a built-in electric motor (motor) 11b. May also be applied. The embodiment shown in FIG. 6 has substantially the same configuration as that shown in FIG. 1 except for the arrangement of the motor 11b (and that the supercharger 20 is not provided), so that the same components are used. Are denoted by the same reference numerals and their detailed description is omitted.
[0042]
In the embodiment shown in FIG. 6, the motor 11b is incorporated so that the rotation axis of the turbine / compressor wheel of the turbo unit 11 becomes the output axis. Even in such a case, since the relationship between the power applied to the motor 20a and the supercharging effect changes, the various control maps differ, but basically the control maps shown in the flowcharts of FIGS. Can be performed similarly.
[0043]
【The invention's effect】
According to the control device for a supercharger with a motor of the present invention, when the vehicle speed is equal to or lower than a predetermined value, the electric power applied to the electric motor is limited, so that the supercharging is performed under the situation where the vehicle speed is equal to or lower than the predetermined value. It can be effectively prevented.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a configuration of an internal combustion engine having one embodiment of a control device of the present invention.
FIG. 2 is a flowchart (first half) of supercharging pressure control according to an embodiment of the control device of the present invention.
FIG. 3 is a flowchart (second half) of boost pressure control according to an embodiment of the control device of the present invention.
FIG. 4 is a graph showing a relationship between a compressor wheel speed (= motor speed) and a supercharging pressure.
FIG. 5 is a flowchart of supercharging pressure control by the control device according to the embodiment of the present invention (when the vehicle is stopped and pre-assisted).
FIG. 6 is a configuration diagram showing a configuration of an internal combustion engine having another embodiment of the control device of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Injector, 3 ... Cylinder, 4 ... Piston, 5 ... Intake passage, 6 ... Exhaust passage, 7 ... Spark plug, 8 ... Intake valve, 9 ... Exhaust valve, 10 ... Air cleaner, 11 ... Turbo unit, 11a: variable nozzle mechanism, 12: intercooler, 13: throttle valve, 14: accelerator pedal, 15: accelerator positioning sensor, 16: ECU, 17: throttle motor, 18: throttle positioning sensor, 19: pressure sensor, 20: supercharging Machine, 20a ... motor (electric motor), 21 ... controller, 22 ... battery, 23 ... exhaust gas purification catalyst, 24 ... bypass passage, 25 ... valve, 26 ... crank positioning sensor, 27 ... air flow meter, 28 ... EGR passage, 29 ... EGR valve.

Claims (3)

A supercharger disposed on an intake passage of an internal combustion engine mounted on a vehicle and driven by an electric motor, a supercharging pressure control means for controlling the electric motor to control a supercharging pressure, and controlling a speed of the vehicle. Speed detecting means for detecting,
The supercharging pressure control means, wherein when the vehicle speed detected by the speed detection means is equal to or less than a predetermined value, the electric power applied to the electric motor is limited to a predetermined electric power or less, Control device. The supercharging pressure control means sets a target rotation speed of the electric motor in a rotation speed region in which a rate of change of the supercharging pressure with respect to the rotation speed of the electric motor is equal to or less than a predetermined value, and sets the electric motor so as to reach the set target rotation speed. The control device for a supercharger with a motor according to claim 1, wherein the electric power applied to the supercharger is determined. 2. The system according to claim 1, wherein the supercharging pressure control means sets a lower target rotation speed of the electric motor as the EGR amount increases, and determines electric power to be applied to the electric motor such that the target rotation speed is set. Or the control apparatus of the supercharger with an electric motor as described in 2.

Images