JPH0747934B2 - Turbocharger controller - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a turbocharger control device in an engine having a turbocharger in which a rotary electric machine is attached to a turbine shaft.

(Prior Art) A turbocharger has been developed in which a rotary electric machine that serves as a motor-generator is attached to a turbine shaft that is driven by exhaust energy of an engine, and a turbocharger that drives the rotary electric machine as an electric motor according to the operating state of the engine is used. An attempt has been proposed to assist the supercharging operation of the charger or to operate the rotating electric machine as a generator to charge the battery with the generated power.

(Problems to be Solved by the Invention) As described above, the turbocharger in which the rotary electric machine is attached to the turbine shaft supplies electric power from the battery to the rotary electric machine when the engine is at low rotation and high load such as a long uphill road. It is driven electrically to raise the supercharging pressure and raise the engine torque. In this case, the electric power supplied from the battery is about 2 KW.

For this reason, semiconductors that switch DC power from a battery to convert it into a pulsating flow, transformers that step up the pulsating flow, and the like handle large amounts of power, so that heat loss becomes large, and the temperature of these parts rises significantly.

Therefore, parts with high temperature resistance are selected in advance as high temperature predicted parts, but when mounted on an actual vehicle and operated under various operating conditions when the temperature is high, the initially set temperature The above operation may occur, and semiconductors and transformers cannot withstand high temperatures, resulting in damage to these parts.

The present invention has been made in view of such problems,
It is an object of the present invention to provide a control device for a turbocharger that attempts to prevent the damage by monitoring the temperature of power conversion components of a turbocharger with a rotating electric machine in which a large current flows and the temperature rises.

(Means for Solving the Problems) According to the present invention, a turbocharger that electrically operates by supplying electric power from a battery to an electric mechanism arranged on a turbine shaft via an electric power converter according to an operating condition of an engine is provided. In the control device, a plurality of detection means for detecting the operating temperature of a plurality of power components constituting the power converter,
And a control means for controlling energization to the electric mechanism based on a signal from each of the detection means, the control means including a signal from each of the detection means and a corresponding power component stored in advance. There is provided a control device for a turbocharger, which includes a determination unit that compares and determines a plurality of allowable temperatures and an electric power control unit that controls the electric power supplied to the electric mechanism according to the output of the determination unit.

(Operation) In the present invention, a temperature sensor is attached to a semiconductor device, a transformer, or the like that is a power component of a DC / DC converter or an inverter that converts DC power from a battery into AC power for driving a rotating electric machine, and the temperature sensor It controls the electric power for driving the rotating electric machine based on the signal, and changes the power control level such as operation stop and current limit depending on the temperature level.
Further, an alarm corresponding to the power control level is output to warn and display the driver.

(Example) Next, the Example of this invention is described in detail using drawing.

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

In the figure, reference numeral 1 is a turbocharger, which comprises a turbine 11 driven by exhaust energy from an engine and a compressor 12 provided on the turbine shaft, and which collects exhaust energy and raises intake pressure of the engine. ,
The rotating shaft between the turbine 11 and the compressor 12 is electrically operated /
A rotating electric machine 13 serving as a generator is attached.

When the engine is running at a low speed and under a high load, the exhaust gas energy discharged from the engine is small and the compressor cannot be sufficiently supercharged. Therefore, the electric energy from the battery 2 is supplied to the rotating electric machine 13 for power running. The rotation of the compressor 12 is urged to increase the supercharging pressure and increase the engine torque. Further, when the engine is at a high speed and the exhaust energy is large, the rotating electric machine 13 is operated as a generator to recover the exhaust energy as electric energy, which can be used to charge the battery 2 or take out the electric power to the outside. It is possible. It should be noted that circuits and members for power generation operation of the rotary electric machine 13 are omitted in FIG.

A DC / DC converter 3 boosts the DC power from the battery 2 to a DC power of a predetermined voltage value, and includes a switching FET 31, a boosting transformer 32, a bridge-connected rectifying circuit 33, and the like. . Then, when the switch 21 is turned on and the switching control command from the controller described later is alternately input to the two FFTs 31 and 31, the DC power from the battery 2 becomes a pulsating current and becomes a transformer.
The primary winding 32 is energized, and a boosted pulsating current is induced in the secondary winding so that the rectifier circuit 33 can obtain DC power of a predetermined voltage.

In the figure, S ₁ is a temperature sensor arranged on the outer surface of the FET 31 to detect the operating temperature of the FET 31, and S ₂ is a transformer 32.
The temperature sensor detects the transformer temperature and sends the detected temperature signal to the controller 5.

Reference numeral 4 denotes an inverter, which has, for example, six transistors 41, and converts the DC power input from the DC / DC converter 3 into three-phase AC power of a predetermined frequency by switching operation of these transistors 41. . Then, each base circuit of the transistor 41 is connected to the signal line from the controller 5, and when a control signal of a predetermined cycle is sequentially applied to the transistor 41, it becomes AC power having a frequency corresponding to the control signal and rotates. It is wired so as to be supplied to the electric machine 13. Note that S ₃ is a temperature sensor arranged on the outer surface of the transistor 41, and sends an operating temperature signal of the transistor 41 to the controller 5.

The controller 5 is composed of a microcomputer and is provided with a central control unit for performing arithmetic processing, various memories for storing arithmetic processing procedures and control procedures, input / output ports, etc., and temperature sensors S ₁ , S ₂ , S ₃ and so on. When signals from the rotary electric machine rotation sensor 14, the engine rotation sensor 51, the accelerator opening sensor 52, etc. are input, predetermined arithmetic processing is performed, and based on the stored map and control procedure, the DC / DC converter 3 FET
31, a control signal is issued to the transistor 41 of the inverter 4, and an alarm for warning the temperature rise of parts is turned on or off.

Reference numeral 61 is an alarm A, which is lit when the FET 31, the transistor 41, the transformer 32, etc. are overheated due to the passing current and there is a risk of damage. Will indicate that the motorized operation of must be stopped immediately. Further, reference numeral 62 is an alarm B, which is lit when the high current causes a breakage due to high temperature to continue to flow, and indicates that it is necessary to reduce the power supply to suppress the temperature rise.

Next, the operation of this embodiment will be described. When the engine is running at a low speed and the exhaust gas amount is small, and the load is large, for example, when the load is large and climbing up a hill, the amount of exhaust energy is small and the compressor is overloaded. The feed operation is not sufficient, and therefore the engine torque cannot be improved.

In such a case, electric power is supplied from the battery 2 to the rotary electric machine 13 via the DC / DC converter 3 and the inverter 4, and the rotary electric machine 13 is made to perform power running to assist the supercharging operation of the compressor 12.

FIG. 2 is a flow chart showing an example of processing of current control and alarm control in electric drive of the rotating electric machine. First, in step 1, detection signals from the engine rotation sensor 51 and the accelerator opening sensor 52 are sent. The map stored in the memory is searched based on these signals, and the current supplied from the battery 2 is set.

Next, the switch 21 is turned on, and a control signal is sent to the FET 31 of the DC / DC converter 3 and the transistor 41 of the inverter 4 to convert the DC power from the battery 2 into AC power for driving the rotating electric machine 13.

For this reason, FET31 and transformer 3 that perform switching operation
2 、 Transistor 41, etc. generate heat by passing current, and the temperature of these parts is detected by each temperature sensor.
It is input to the controller 5 by S ₁ , S ₂ and S ₃ .

In step 2, the temperature signals from the temperature sensors S ₁ , S ₂ , S ₃ are checked, the temperature signal is compared with the temperature T _{1 at} which there is a risk of damage, and if T ₁ is reached, step 3 Then, the alarm A is turned on and the switch 21 is turned off to stop the power supply to the rotary electric machine 13 to suspend the operation of the DC / DC converter and the inverter 4.

Note that the temperature check in step 2 is based on the semiconductor temperature as an example, and the flow is processed according to each of the FET 31, the transformer 32, and the transistor 41 in FIG. However, when even one of the temperature sensors S ₁ , S ₂ , S ₃ reaches a temperature at which there is a risk of damage, the alarm A is turned on and the operation is stopped.

Returning to the process of FIG. 2, if the temperature T ₁ at which there is a risk of damage has not been reached in step 2, the process proceeds to step 5, in which the temperature at which damage will occur if a large current continues to flow.
Compare T ₂ with the temperature signal from the temperature sensor. And
When the temperature T ₂ is reached, the process proceeds to steps 6 to 9, the alarm A is turned off, the alarm B is turned on, and the current is limited to a current obtained by subtracting the value of K, and the DC / DC converter is controlled. 3 and the inverter 4 are operated to supply AC power to the rotating electric machine 13 to drive it. In this case, since the limited current passes, heat generation of the electric power components is suppressed, and thermal damage is avoided even when the operation is continued.

In step 5, the temperature signal from the temperature sensor is the temperature T ₂
If it has not reached, the process proceeds to Steps 10 to 12, the alarm A and the alarm B are turned off, the DC / DC converter 3 and the inverter 4 are operated without limiting the input current, and AC power is supplied to the rotating electric machine 13. The electric motor will continue to operate.

Although the present invention has been described above using 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.

(Effects of the Invention) According to the present invention, a temperature sensor is attached to a semiconductor device, a transformer, or the like that is a power component of a DC / DC converter or an inverter that converts direct-current power from a battery into alternating-current power, and a signal from the temperature sensor is attached. It controls the electric power for driving the rotating electric machine based on the above, and changes the electric power control level such as operation stop and current limit depending on the temperature level.
Since an alarm is output to the driver by outputting an alarm according to the power control level, the temperature of the power component will not rise above the predicted temperature due to the outside air temperature or the operating condition, and the power due to overheating will not be generated. There is an advantage that the damage of the parts is eliminated, and the driver can fully understand the dangerous state by lighting the alarm.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a processing flow chart showing an example of the processing of this embodiment. 1 ... Turbocharger, 2 ... Battery, 3 ... DC / D
C converter, 4 ... Inverter, 5 ... Controller, 13 ... Rotating electric machine, 31 ... FET, 32 ... Transformer, 41
...... Transistor, 61 …… Alarm A, 62 …… Alarm B, S ₁ , S ₂ , S ₃ …… Temperature sensor.

Claims (2)

[Claims] 1. A turbocharger control device configured to supply electric power from a battery via a power conversion device to an electric mechanism arranged on a turbine shaft to electrically operate the electric power conversion device according to engine operating conditions. A plurality of detecting means for detecting operating temperatures of a plurality of electric power components, and a control means for controlling energization to the electric mechanism based on a signal from each detecting means. Determination means for comparing and determining a signal from the means and a plurality of allowable temperatures of the corresponding power components stored in advance, and power control means for controlling the power supplied to the electric mechanism by the output of the determination means. A control device for a turbocharger, comprising: 2. The control device for a turbocharger according to claim 1, wherein the control means is provided with warning means according to control of energization.