JP3208872B2 - Control device for rotating electric machine for turbocharger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention controls a supply current when a rotary electric machine serving as a motor-generator is mounted on a rotary shaft of a turbocharger and a supercharging operation is assisted by an electric drive of the engine under a high load. The present invention relates to a control device for a rotary electric machine for a turbocharger.

[0002]

2. Description of the Related Art A rotating electric machine that performs an electric-power generation operation is mounted on a rotating shaft of a turbocharger. For example, when the engine is operated at a low rotation speed and a high load, electric power is supplied to the rotating electric machine so that the rotating electric machine operates as a motor to increase the intake pressure of the engine. Various proposals have been made to improve the torque by using a rotary electric machine or to generate electric power when the exhaust energy has a margin.

[0003] In such a case, the driving control of the rotating electric machine is performed as follows.
A controller that inputs the engine rotation, the turbine rotation, the accelerator opening, the boost pressure, and the like is used, and the processing unit determines the processing and issues a command to the electric power unit to perform the electric drive or the power generation operation. For the current instruction in the case of electric drive, a current value according to a stored data map or the like is set according to each operation mode, for example.
This value is usually determined based on the accelerator opening and the engine speed.

[0004]

The rotating electric machine as described above is subjected to V / F control, and the supply voltage is increased in proportion to the rotation speed of the turbocharger. The upper limit of the number of revolutions is changed between the case where the current instruction is large and the case where the current instruction is small as the inverter characteristic of the power unit that supplies the power, and this is due to the capacity of the power unit.

Therefore, when the rotating electric machine is electrically driven by the electric power supplied from the electric power unit, unless the current is limited in accordance with the number of revolutions, chattering occurs in which a large current is repeatedly turned on and off when a large current is supplied. There is a possibility that a failure may occur due to a burden on the unit.

[0006] Also, Japanese Patent Application Laid-Open No. 3-81525 discloses that
A control device for a turbocharger with a rotating electric machine that controls power supply according to a tendency of increase / decrease of the turbine shaft rotation speed when the turbine shaft reaches near its upper limit rotation speed is shown. Is not taken into account, and in the case of an increase in power, there is a disadvantage that an accident occurs due to excessive power of the power unit.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and has as its object to limit the supply current so as not to exceed the maximum current instruction value by considering the characteristics of the power unit according to the turbine speed. Accordingly, an object of the present invention is to provide a control device for a rotary electric machine for a turbocharger, which prevents chattering and an overload state.

[0008]

According to the present invention, in order to achieve the above object, the present invention is mounted on a turbine shaft of a turbocharger, and is electrically driven by a supply current from an electric power unit in accordance with an operation state of an engine. In the control device of the rotary electric machine for a turbocharger that assists the supercharging operation of the turbocharger, an excessive supply current is set by setting an upper limit supply current value according to a turbine speed based on the capacity of the power unit. A control device for a rotary electric machine for a turbocharger, provided with a drive current limiting means for limiting.

[0009]

When a large current is supplied from a power unit to a rotary electric machine for a turbocharger to be electrically driven, a maximum current value limited according to the turbine speed is designated and energized in consideration of the capacity of the power unit. Therefore, an overload state of the power unit can be prevented.

[0010]

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a control device for a rotary electric machine for a turbocharger according to the present invention. In FIG. 1, reference numeral 1 denotes a turbocharger, which is connected to an engine 2 by an exhaust pipe 21 and an intake pipe 22, and when a turbine 11 is driven by exhaust gas through an exhaust pipe 12, a compressor 13 attached to a turbine shaft 12 is provided.
Rotates, and pressurizes the supercharged air to the engine 2 through the intake pipe 22 by the pneumatic operation.

Reference numeral 3 denotes a rotating electric machine serving as a motor-generator. The rotor 31 is disposed on the turbine shaft 12, and the corresponding stator 32 is mounted on the housing 14. And
When there is a margin in the exhaust energy depending on the operation state of the engine 2, the rotating electric machine 3 is operated to generate electric power and the generated electric power from the stator 32 is guided to the electric power unit 4 to charge the battery 5, or the engine 2 At the time of load, the electric power from the battery 5 is led to the inverter of the electric power unit 4, converted into AC power of a predetermined frequency based on the rotation speed of the rotor 31 and supplied to the stator 32, and the compressor 13 is driven by the rotating electric machine 3. To boost the boost pressure. In addition, 24 is a boost pressure sensor attached to the intake pipe 22 to detect a supercharging pressure, 23 is an engine rotation sensor that detects the rotation speed of the engine 2, 15 is a turbine rotation sensor that detects the rotation speed of the turbine, Detection signals from these sensors are connected so as to be input to a controller described later.

The controller 6 comprises a microcomputer, a central controller for performing arithmetic processing, an arithmetic processing procedure,
It is provided with various memories for storing control procedures and data maps, input / output ports, and the like. When a detection signal from the various sensors or the accelerator opening sensor 71 corresponding to the depression of the accelerator pedal 7 is input, a predetermined arithmetic processing unit is performed, and based on the stored control procedures and data maps, etc. The electric power unit 4 is instructed to control the supply current to the rotating electric machine 3 and control the output from the rotating electric machine 3.

In this embodiment, when controlling the supply current, a current limit curve diagram at the time of electric drive with respect to the accelerator opening, the engine speed and the turbine speed as shown in FIG. A current instruction value curve diagram that is limited according to the number is used as data.

FIG. 4 is a processing flow chart showing an example of the operation of this embodiment. Next, the operation of this embodiment will be described with reference to FIG.

The controller 6 in this embodiment performs processing in the central controller in accordance with signals from the engine rotation sensor 23, the accelerator opening sensor 71, and the like.
In this case, it is determined in step 1 in FIG. 4 whether the turbine rotation speed has reached 80,000 rpm based on a signal from the turbine rotation sensor 15. Then, when the rotation speed has not reached 80,000 rpm, the process returns to the predetermined main control in step 2, but in the above case, the flow proceeds to step 3 to check whether the turbine speed has reached 90,000 rpm.

In step 3, if the rotation speed does not reach 90,000 rpm, the process proceeds to step 4, in which the maximum current is limited to 50 A or less between 80,000 rpm and 90,000 rpm according to the stored data and map. Find the indicated value. Next, in step 8, the maximum current instruction value is compared with the current instruction value M calculated in each control mode, and when the current instruction value M is large, the process proceeds to step 10, and as the current value to be instructed to the power unit 4, The maximum current instruction value according to the turbine speed is commanded to be the current supplied to the rotating electric machine 3.

If the result of step 8 is negative, the electric current value of the current instruction value M is instructed to the power unit 4 to execute the electric operation.

In step 3 above, the turbine speed is 9
If it is not less than 10,000 rpm, the routine proceeds to step 5, where it is determined whether or not the turbine speed is not less than 96,000 rpm. And 9.
If the rotation speed is equal to or less than 60,000 rpm, the process proceeds to step 6, where the maximum current instruction value corresponding to the turbine speed, that is, the current instruction value between 40A and 10A, is obtained, and the process proceeds to step 8.
Here, similarly to the above, the maximum current instruction value limited according to the turbine speed is compared with the current instruction value M calculated in the control mode, and based on the comparison, the power A command for a current value is issued, and the rotating electric machine 3 is driven electrically.

It should be noted that 9.6 is determined by the judgment in step 5.
If the rotation speed is equal to or greater than 10,000 rpm, the current instruction value is set to 0 in step 7, and the energization to the rotating electric machine 3 is stopped.

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

[0022]

According to the present invention as in the above embodiment,
When the rotating electric machine mounted on the turbocharger is electrically driven, the rotating electric machine is energized by instructing the maximum current value that is limited according to the turbine speed in consideration of the capacity of the electric power unit. Is not overloaded, so that chattering and the like can be prevented, and there is an effect of avoiding a failure.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram showing one embodiment of a control device for a rotary electric machine for a turbocharger according to the present invention.

FIG. 2 is a limit current curve diagram at the time of electric driving in the present embodiment.

FIG. 3 is a current instruction curve diagram for limiting according to the turbine speed in the embodiment.

FIG. 4 is a processing flowchart illustrating an example of the operation of the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Turbocharger 2 ... Engine 3 ... Rotary electric machine 4 ... Electric power part 6 ... Controller 12 ... Turbine shaft 15 ... Turbine rotation sensor

Claims (1)

(57) [Claims] A control device for a rotary electric machine for a turbocharger, which is mounted on a turbine shaft of a turbocharger, is electrically driven by a supply current from an electric power unit in accordance with an operation state of an engine, and assists a supercharging operation of the turbocharger. A drive current limiting means for setting an upper limit supply current value according to the turbine speed based on the capacity of the power unit, and limiting excessive supply current. Electric machine control device.