JP2008175074A - Turbocharger with demagnetization notifying motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect and notify a user that the magnetic force of a permanent magnet is lost. <P>SOLUTION: A turbocharger 2 with a motor comprises a turbocharger 1 operable in combination with an engine 4, a permanent magnet synchronizing motor 3 axially coupled to the turbocharger 1, and a drive control means E' for drivingly controlling the permanent magnet synchronizing motor 3 by supplying a motor drive current thereto. This turbocharger E with a demagnetization notifying motor comprises, in addition to the turbocharger 2 with a motor, an engine start detection means 5 for detecting the start of the engine 4 and outputting an engine start signal X1, a magnetic sensor 6 for detecting the rotation of a permanent magnet 3a forming the rotor of the permanent magnet synchronizing motor 3 and outputting a magnetic flux variation signal Y1, and a comparison detection means for comparing the engine start signal X1 with the magnetic flux variation signal Y1, and when the magnetic flux variation signal Y1 is determined to be weaker than a threshold, outputting a demagnetization notifying signal Z. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a turbocharger with an electric motor.

A synchronous motor, which is a regenerative generator, is attached to the rotating shaft of the turbocharger, and it is possible to recover the exhaust energy as electric power by generating power according to the operating state of the engine. Devices for assisting are known. For example, in a drive control device that energizes a permanent magnet type synchronous motor that generates electricity according to the operating state of the engine, a regenerative power generation output is generated by the rotation of the permanent magnet, and the rotation phase is detected by detecting it. Means detect rotation speed and phase. A synchronous motor drive control device is known in which a power supply means sets a frequency and a phase of power supplied to a synchronous motor based on a signal from the rotational phase detection means (Patent Document 1).
Japanese Patent Laid-Open No. 6-113598

  However, in the technique of Patent Document 1, the magnetic force of the permanent magnet that constitutes the rotor of the synchronous motor is indispensable. If the magnetic force of the permanent magnet disappears due to overheating, it becomes a turbocharger without electric drive assist (hereinafter also referred to as “electric assist”), which was originally possible for the demand for rapid acceleration during engine operation There was a problem that torque could not be applied.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to detect and notify a user that the magnetic force of a permanent magnet has disappeared in a turbocharger using a permanent magnet synchronous motor. It is.

  In order to achieve the above object, a first invention is a turbocharger operable in combination with an engine, a permanent magnet synchronous motor axially coupled to the turbocharger, and a motor drive current of each phase in the permanent magnet synchronous motor. In addition to a turbocharger with an electric motor, the engine start detecting means for detecting the start of the engine and outputting an engine start signal, and the rotation of the permanent magnet synchronous motor A magnetic sensor for detecting rotation of a permanent magnet constituting the child and outputting a magnetic flux change signal; and a comparison detection means for detecting whether the magnetic flux change signal is equal to or less than a threshold value during startup of the engine. It is characterized by comprising.

  As a second aspect of the invention, as the engine start detection means, winding heat generation detection means for detecting an increase in winding temperature of the permanent magnet synchronous motor, turbocharger heat generation detection means for detecting a temperature increase of the turbocharger, It is characterized by comprising at least one of a turbocharger pressure increase detection means for detecting an increase in pressure of the turbocharger and a turbocharger flow detection means for detecting the start of flow of the turbocharger.

  The third invention is characterized in that, instead of the magnetic flux change signal, a counter electromotive force generated along with the rotation of the permanent magnet synchronous motor is also used.

  According to a fourth aspect of the invention, the magnetic sensor also serves as a rotational phase speed detection means used for the drive control.

  According to the first invention, in a turbocharger using a permanent magnet synchronous motor, even if there is an engine start signal, if there is no magnetic flux change signal, it is determined that the magnetic force of the motor has disappeared and the demagnetization notification signal Is output. Thus, it is possible to notify the user by detecting that the magnetic force of the permanent magnet constituting the rotor of the motor has disappeared due to overheating.

  According to the second invention, at least one of sensors already installed in the turbocharger using the permanent magnet synchronous motor, for example, winding heat generation detection means, turbocharger heat generation detection means, turbocharger boost detection means, turbocharger flow detection means. It is possible to detect that the engine is running by using the signal as well. Therefore, it is possible to add a demagnetization notification function with little cost increase.

  According to the third to fourth inventions, the drive control means for supplying and controlling the motor drive current of each phase to the permanent magnet synchronous motor, that is, the existing sensor is also used for the motor driver, and the signal is used. By doing so, it is easy to detect the counter electromotive force and rotational phase speed of the motor, and it is possible to add a demagnetization notification function with little cost increase.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2 alternately.
FIG. 1 is a block diagram of a demagnetization notification type turbocharger with an electric motor (hereinafter referred to as “this device”) E according to the present embodiment. The apparatus E shown in FIG. 1 is obtained by adding a demagnetization notification function for outputting a demagnetization notification signal Z to the turbocharger 2 with electric motor.

  The turbocharger 2 with an electric motor supplies a motor drive current of each phase to the turbocharger 1 that can be combined with the engine 4, the permanent magnet synchronous motor 3 that is axially coupled to the turbocharger 1, and the permanent magnet synchronous motor 3. Drive control means E ′ for drive control. The drive control means (hereinafter referred to as “driver”) E ′ is configured to be able to drive and control the inverter 11 that operates with the electric power of the battery 10 based on control by the ECU 8. However, since the driver E ′ before adding the demagnetization notification function is well known, the details thereof will be omitted together with the drawings.

  The demagnetization notification function detects the start of the engine 4 and outputs the engine start signal X1, and detects the rotation of the permanent magnet 3a constituting the rotor of the permanent magnet synchronous motor 3 to change the magnetic flux. The magnetic sensor 6 that outputs the signal Y1, and the comparative detection that outputs the demagnetization notification signal Z if it is determined that the magnetic flux change signal Y1 is weaker than the threshold value when it is confirmed by the engine start signal X1 that the engine 4 is starting. Means 7 are provided.

  The turbocharger 1 includes a turbine 1a that rotates upon receiving exhaust from the engine 5, and a compressor 1b that rotates coaxially with the turbine 1a. The turbocharger 2 with an electric motor is formed by a permanent magnet synchronous motor (hereinafter also referred to as “motor”) 3 that is coupled to the turbocharger 1 so as to be coaxially rotatable.

  The turbocharger 2 with the electric motor increases in rotational speed when the turbine 1a is driven by the exhaust gas of the engine 4, while the rotational speed also increases with assistance from the motor 3 (electrical assist), and the rotation of the turbocharger 2 with electric motor rotates. The number rises rapidly, for example, from a low speed rotation of several thousand to about 10,000 rotations per minute to a high speed rotation exceeding about 100,000 rotations per minute.

  The engine 4 is controlled by a command from the ECU 8. The turbocharger with motor 2 is appropriately driven and controlled by a command from a microcomputer 9 for controlling the turbocharger with motor (hereinafter also referred to as “control microcomputer”) 9 connected to the ECU 8.

  The control microcomputer 9 stores a control table (not shown) in which the engine operation status is patterned, and appropriately issues a control signal according to each operation status such as startup, acceleration, cruise, deceleration, and stop. . The inverter 11 interposed between the motor 3 and the battery 10 supplies the electric power of the battery 10 to the motor 3 when the electric assist is turned on while receiving support from the control microcomputer 9. Preferably, the regenerative power generated by the motor 3 is returned to charge the battery 10 when the electric assist is OFF.

  The engine start detection means 5 detects the start of the engine 4 and outputs an engine start signal X1. The magnetic sensor (position sensor) 6 detects the rotational phase and speed of the permanent magnet 3 a constituting the rotor of the motor 3, outputs a magnetic flux change signal Y 1, and inputs it to the control microcomputer 9. The magnetic sensor 6 also serves as the rotational phase speed detection means 6 used for driving control of the motor 3. Alternatively, instead of the magnetic flux change signal Y1, the counter electromotive force Y2 generated with the rotation of the motor 3 may also be used.

  Further, other methods may be used as the engine activation detection means 5. For example, it is also effective to detect an increase in the winding temperature of the motor 3 based on the motor winding temperature signal X2 output from the winding heat generation detection means 51. That is, since an electric assist command is issued from the ECU 8 and the control microcomputer 9 when the engine is started, the winding temperature of the motor 3 rises and the control microcomputer 9 recognizes the motor winding temperature signal X2 to recognize the engine start. can do.

  It is also effective to detect the temperature rise of the turbocharger 1 by the turbocharger heat generation detection means 52 as the engine activation detection means 5. That is, when the engine is started, high temperature exhaust gas flows through the turbine 1a, so that it can be detected that the temperature of the turbocharger 1 rises.

  Similarly, it is also effective to detect an increase in the pressure of the turbocharger 1 by the turbocharger boost detection means 53. That is, when the engine is started, both the turbine 1a and the compressor 1b increase in pressure when the turbocharger 1 starts rotating, and this can be detected.

  It is also effective to provide a flow sensor or the like so that the turbocharger flow detection means 54 detects the start of flow to the turbocharger 1. In either case, a corresponding sensor may be disposed at the inlet or outlet of each of the turbine 1a and the compressor 1b.

  FIG. 2 is an explanatory diagram of the comparison detection means 7 that outputs the demagnetization notification signal Z. The comparison detection means 7 shown in FIG. 2 compares the engine start signal X1 and the magnetic flux change signal Y1, and outputs a demagnetization notification signal Z when it is determined that the magnetic flux change signal Y1 is weaker than the threshold value. Here, if the control microcomputer 9 receives the engine activation signal X1 from the ECU 8, it is considered that the engine 4 is activated. That is, if there is no magnetic flux change signal Y1 despite the presence of the engine start signal X1, it is determined that the magnetic force of the motor 3 has disappeared and the demagnetization notification signal Z is output.

  Next, the operation of the apparatus E to issue the demagnetization notification signal Z and the effects thereof will be described. The rotor 3a of the motor 3 is composed of a permanent magnet 3a (same as the rotor) made of a ferromagnetic material. The permanent magnet 3a loses its magnetic force when its temperature rises, and completely loses its magnetic force when it reaches the Curie temperature for each material. By the way, the Curie temperature of iron is 770 degrees C, and nickel is 354 degrees C. On the other hand, there is a definition of a use temperature at which the weakened magnetic force does not return even below the Curie temperature. For example, the use temperature of a neodymium magnet is about 60 to 80 degrees C.

  The use condition of the motor 3 is restricted by the use temperature. If the exhaust gas temperature of the engine 4 rises abnormally for some reason, the turbocharger 1 will not only be damaged, but the magnetic force of the permanent magnet 3a will suddenly weaken in a temperature environment exceeding the operating temperature determined by the ferromagnetic material. When the temperature reaches the Curie temperature, the motor 3 simply idles and the functions of the electric assist and / or regenerative power generation disappear. As a result, the turbocharger 1 that is not electrically assisted has a torque enhancement performance when the engine is accelerated, and the regenerative power generation does not function, so that the charging of the battery 10 is also less than the regulation, causing a problem.

  For this reason, when the magnetic force of the permanent magnet 3a disappears, it is desirable to repair it quickly for the magnetization process again. In order to inform the user of this, if the device E issues a demagnetization notification signal Z and, for example, displays a warning on the dashboard of the automobile, the loss of neglecting the failure can be minimized. In addition, it is highly possible that the engine exhaust gas temperature rises abnormally because of the engine failure, and the cause of the engine failure is investigated before the remagnetization processing of the disappearing magnetic force. There is also a secondary effect of prolonging.

  In addition to the motor winding temperature signal X2, as a signal replacing the engine start signal X1, a signal X3 indicates a change in the inlet temperature, outlet temperature, inlet flow rate, outlet flow rate, inlet pressure or outlet pressure of the turbine 1a. Can be used as Furthermore, changes in which the inlet temperature, outlet temperature, inlet flow rate, outlet flow rate, inlet pressure, and outlet pressure of the compressor 1b increase can be used as the signal X4. These can be easily realized by using at least one of the turbocharger heat generation detection means 52, the turbocharger pressure increase detection means 53, and the turbocharger flow detection means 54 included in the engine start detection means 5, so that an existing temperature sensor, pressure If either a sensor or a flow sensor is used, the cost increase can be reduced.

It is a block diagram which shows the turbocharger with a demagnetization alerting | reporting type motor which concerns on this embodiment. It is explanatory drawing of the comparison detection means which outputs a demagnetization alert signal.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Turbocharger 1a Turbine 1b Compressor 2 Turbocharger with electric motor 3 Permanent magnet synchronous motor (motor)
3a Permanent magnet (rotor)
4 Engine 5 Engine start detection means 6 Magnetic sensor 7 Comparison detection means X1 Engine start signal Y1 Magnetic flux change signal Z Demagnetization notification signal E Demagnetization notification type turbocharger with motor (this device)
E 'Drive control means (motor driver)

Claims (4)

A turbocharger that can operate in combination with the engine;
A permanent magnet synchronous motor axially coupled to the turbocharger;
In addition to a turbocharger with an electric motor, including a drive control means for supplying and controlling the electric motor driving current of each phase to the permanent magnet synchronous motor,
Engine start detection means for detecting engine start and outputting an engine start signal;
A magnetic sensor for detecting a rotation of a permanent magnet constituting a rotor of the permanent magnet synchronous motor and outputting a magnetic flux change signal;
A demagnetizing alarm type motor-equipped turbocharger, comprising: a comparison detection unit configured to detect whether or not the magnetic flux change signal is equal to or less than a threshold value during startup of the engine. As the engine start detection means,
Winding heat generation detecting means for detecting an increase in winding temperature of the permanent magnet synchronous motor;
Turbocharger heat detection means for detecting a temperature rise of the turbocharger;
Turbocharger boost detection means for detecting an increase in pressure of the turbocharger;
The turbocharger with a demagnetization notification motor according to claim 1, further comprising at least one of turbocharger distribution detecting means for detecting the start of circulation of the turbocharger.   The demagnetization notification type motor according to any one of claims 1 to 2, wherein a counter electromotive force generated in association with rotation of the permanent magnet synchronous motor is also used instead of the magnetic flux change signal. Turbocharger with.   The demagnetization notification type motor-equipped turbocharger according to any one of claims 1 to 3, wherein the magnetic sensor also serves as a rotational phase speed detection means used for the drive control.

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