JP2020070895A - Vibration damping device - Google Patents

Abstract

To provide a vibration damping device that includes a vibration detection unit for detecting vibration of a vibration damping object and is improved in accuracy for controlling vibration damping.SOLUTION: A vibration damping device includes: an auxiliary mass; an excitation unit for reciprocating the auxiliary mass; a vibration detection unit for detecting vibration of a vibration damping object; and a control unit for generating a damp command for driving the excitation unit on the basis of an output signal from the vibration detection unit.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vibration damping device that suppresses vibration of a vibration damping target.

  Conventionally, a vibration suppression that suppresses the vibration of the vibration suppression target by the vibration generated when the vibration of the vibration suppression target is detected and the actuator is driven based on the detected vibration to reciprocate the auxiliary mass. A device is known (for example, see Non-Patent Document 1).

  Generally, in a vibration damping device, a speed is calculated based on acceleration (vibration acceleration) detected by an acceleration sensor, the calculated speed is converted into an actuator drive signal by an integrator, and the actuator is driven by speed feedback control. However, since the driving force (control force) of the actuator is proportional to the speed (vibration speed) of the object to be damped, the above vibration damping device drives the actuator by voltage by multiplying the acceleration by a temporary delay element. This eliminates the need for an integrator and simplifies the vibration damping device.

  Specifically, in the above vibration damping device, a signal obtained by electrically converting the detected value of the acceleration of the vibration damping target is output from the acceleration sensor, and the output signal is multiplied by a first-order lag element to calculate the speed, By applying the calculated signal to the actuator as a damping command, it is possible to control the vibration of the vibration suppression object without a separate integrator.

Ryosuke Yamauchi, 3 others, “New vibration isolation technology using passive and active”, Proceedings of 2017 Spring Conference Academic Lecture, Japan Society of Automotive Engineers, May 22, 2017, p. 354-359

  However, in the above vibration damping device, by processing the output signal of the acceleration sensor by the first-order lag element, the time response of the damping command calculated after this processing deteriorates with respect to the output signal of the acceleration sensor. Therefore, the accuracy of the vibration suppression control may be reduced.

  Therefore, it is an object of the present invention to provide a vibration damping device that includes a vibration detection unit that detects the vibration of a vibration damping target and that improves the accuracy of vibration damping control.

  The inventors of the present invention have conducted earnest research to solve the above-mentioned problems, and as a result, the output signal of the acceleration sensor has a phase delay with respect to the vibration of the vibration suppression target, and the degree of the phase delay is the output type. It turned out to be different. Therefore, by focusing on the degree of the phase delay, it was discovered that the vibration of the vibration suppression target can be suppressed without performing the processing of the primary delay element on the output signal of the acceleration sensor. The details are as follows.

  A conventional vibration damping device generates a control force by processing an output signal of an acceleration sensor with a first-order lag element and applying it to an actuator as a damping command. That is, the phase of the damping command is adjusted to be delayed by about 90 degrees with respect to the output signal of the acceleration sensor by performing the processing by the first-order delay element, and becomes the same phase as the speed based on the output signal of the acceleration sensor. Then, by driving the actuator with the adjusted damping command, the vibration of the vibration suppression object is suppressed.

  However, in the conventional vibration damping device, since the generation of the damping command is processed by the first-order lag element, the time response of the control is deteriorated, which may lead to a reduction in the accuracy of the vibration damping control. Therefore, we researched a method of generating a damping command for the output signal of an acceleration sensor without processing it with a first-order lag element. As a result, it was found that the output signal of the acceleration sensor has a phase delay with respect to the vibration applied to the acceleration sensor. Further, since the digital acceleration sensor generally has a built-in A / D converter and the like, it has been found that the phase delay of the output signal of the digital acceleration sensor is larger than that of the analog acceleration sensor. ..

  Therefore, by utilizing the phase delay of the output signal of the digital acceleration sensor, it is possible to suppress the vibration of the vibration suppression target without processing the output signal of the acceleration sensor by the primary delay element.

  Based on the above findings, the inventors have created a vibration damping device having the following configuration, which focuses on the characteristics of a digital acceleration sensor.

The vibration damping device according to the present invention is
An auxiliary mass and a vibrating section that reciprocates the auxiliary mass,
A vibration detection unit that detects the vibration of the vibration suppression object,
A control unit that generates a damping command for driving the vibration applying unit based on an output signal of the vibration detecting unit,
The phase of the output signal is delayed by about 90 degrees with respect to the phase of the input vibration of the vibration detector.

  With such a configuration, when detecting the vibration of the vibration suppression target and suppressing the vibration, the phase of the output signal of the vibration detection unit has a phase characteristic in which it is delayed by about 90 degrees with respect to the phase of the input vibration. By using the part, the accuracy of the vibration damping control is improved.

In the vibration damping device,
The delay of the phase of the output signal with respect to the phase of the input vibration of the vibration detection unit is about 90 degrees when the vibration of the vibration suppression target that vibrates at the resonance frequency of the vibration suppression target is detected. Good.

  By suppressing the resonance of the vibration suppression target using the vibration detection unit having such a phase delay, it is possible to reduce the vibration in the resonance region including the peak of the resonance frequency of the vibration suppression target.

In the vibration damping device,
The vibrating section may be current controlled.

  With such a configuration, it is possible to perform control with higher accuracy (higher vibration damping property) as compared with the case where voltage is applied to the vibration applying unit.

  As described above, according to the present invention, it is possible to provide a vibration damping device that includes a vibration detection unit that detects the vibration of a vibration damping target, and that has improved vibration damping control accuracy.

FIG. 1 is a schematic diagram showing an arrangement state of the vibration damping device according to the present embodiment. FIG. 2 is a block diagram showing the configuration of the vibration damping device. FIG. 3 is a phase characteristic diagram of the output signal of the acceleration sensor for each output type. FIG. 4 is a block diagram of the vibration damping device according to the present embodiment. FIG. 5 is an analysis diagram when damping control is performed by the damping device according to the present embodiment. FIG. 6 is an analysis diagram when damping control is performed by the damping device of the modified example.

  An embodiment of the present invention will be described below with reference to FIGS.

  The vibration damping device according to the present embodiment is used in a vibration damping system applied to an automobile Ca, as shown in FIG. Specifically, the vibration damping device 1 is mounted on the vibration damping target T (torque rod T) and suppresses the vibration of the torque rod T. The torque rod T is arranged between the vibration source E (engine E) and the vehicle body Ch.

  Specifically, as shown in FIG. 2, the vibration damping device 1 includes an auxiliary mass 2 having a predetermined mass, a vibration unit 3 for reciprocating the auxiliary mass 2, and vibration detection for detecting the acceleration of the torque rod T. The unit 4 and the control unit 5 that controls the vibration unit 3 are provided. This vibration damping device 1 uses the auxiliary mass 2 so as to cancel the vibration of the engine E by the vibration unit 3 based on the signal of the engine E (for example, an ignition pulse signal or the like) and the detection signal of the vibration detection unit 4. By reciprocating, the resonance of the torque rod T is suppressed and the vibration is reduced.

  In a general vehicle engine, the resonance frequency of primary vibration such as bending vibration and torsional vibration of the engine is about 280 Hz to 350 Hz. Therefore, the resonance frequency of the engine and the resonance frequency of the torque rod are adjusted to be lower than the resonance frequencies of the engine such as bending vibration and torsional vibration. In the present embodiment, in the vibration damping system adjusted so that the resonance frequency of the torque rod T is around 200 Hz, it is assumed that the resonance of the torque rod T is suppressed to reduce the vibration.

  The vibration unit 3 (hereinafter, actuator 3) is a linear actuator (reciprocating motor), and has a shaft 31 connected to the auxiliary mass 2, a mover 32 connected to the shaft 31, and a stator 33 including a permanent magnet. And have. In this actuator 3, an AC current (a sine wave current, a rectangular wave current, etc.) is passed through a coil (not shown) of the stator 33, so that the force applied to the mover 32 toward one side in the axial direction of the shaft 31. The force on the other side acts alternately and the shaft 31 reciprocates in the axial direction.

  The vibration detector 4 (hereinafter, acceleration sensor 4) is a digital acceleration sensor and is installed on the torque rod T. The acceleration sensor 4 detects the acceleration of the torque rod T by the detection element 4a of the sensor such as a piezoelectric element based on the vibration applied from the torque rod T (hereinafter referred to as input vibration), and detects the detected value (hereinafter, sensor input). The signal) is electrically converted, and the converted signal (sensor output signal) is output to the control unit 5.

  FIG. 3 shows an example of phase characteristics of sensor output signals of the analog acceleration sensor and the digital acceleration sensor. In the acceleration sensor 4 of the present embodiment, when the frequency of the sensor input signal is around 200 Hz, which is the peak of the resonance frequency of the torque rod T, the phase of the sensor output signal is approximately 90 deg (degrees) with respect to the phase of the sensor input signal. Running late. When the phase is delayed by 90 degrees, the sensor output signal becomes in phase with the phase of the input vibration. When the phase is delayed by 90 deg, the acceleration becomes in phase with the phase of velocity. That is, when the acceleration of the torque rod T is detected using the acceleration sensor 4 having the phase characteristic as in the present embodiment, the phase of the sensor output signal is the actual speed of the torque rod T (actual vibration speed of the torque rod T). Since it has the same phase as, the sensor output signal can be treated as the actual speed of the torque rod T.

  The control unit 5 performs a current control of the actuator 3 based on a damping command generation unit 51 that generates a damping command for canceling the vibration of the torque rod T at a specific frequency from the sensor output signal of the acceleration sensor 4, and the damping command. And a current control unit 52. Further, in the present embodiment, the sensor output signal of the acceleration sensor 4 can be treated as the actual speed of the torque rod T, so that the speed control of the control unit 5 uses open loop control.

  As shown in FIG. 4, the damping command generation unit 51 applies a high-pass filter (HPF) to remove the DC component of the sensor output signal of the acceleration sensor 4, and multiplies the value by a negative damping gain G. Thus, the damping command is generated. Therefore, the damping command generation unit 51 can generate a damping command that is proportional to the actual speed of the torque rod T, and it is not necessary to adjust the phase of the sensor output signal.

  The current control unit 52 current-controls the actuator 3 based on the damping command generated by the damping command generation unit 51, and outputs a signal corresponding to a driving current for reciprocally driving the auxiliary mass 2. The current control unit 52 of this embodiment performs so-called PI control.

  FIG. 5 shows an example of an analysis result when the resonance of the torque rod T is suppressed and the vibration is reduced by the conventional technique and the present embodiment.

  In the case of the prior art, since the sensor output signal is processed by the first-order lag element, when the frequency of the input vibration is around 200 Hz which is the peak of the resonance frequency of the torque rod T, the phase of the sensor output signal is the phase of the input vibration. It lags behind the phase by approximately 90 degrees. However, since there is a phase delay in the resonance region including the peak of the resonance frequency of the torque rod T, there is a possibility that the time response will deteriorate and the vibration suppression control accuracy will decrease. On the other hand, in the case of the present embodiment, when the frequency of the input vibration is around 200 Hz which is the peak of the resonance frequency of the torque rod T, the phase of the sensor output signal is not processed by the primary delay element. Is delayed by approximately 90 deg with respect to the phase of the input vibration. Further, since there is almost no phase delay in the resonance region of the torque rod T, the accuracy of vibration damping control is improved.

  According to the vibration damping device 1 described above, when detecting the acceleration of the torque rod T and suppressing the vibration, the acceleration sensor 4 having a phase characteristic in which the phase of the sensor output signal is delayed by about 90 deg with respect to the phase of the input vibration is used. By doing so, it is possible to generate a damping command without processing the sensor output value with a first-order lag element, so it is possible to prevent the time response from deteriorating with respect to the sensor output value. The accuracy of is improved.

  Further, in the vibration damping device 1 of the present embodiment, when the frequency of the input vibration is around 200 Hz which is the peak of the resonance frequency of the torque rod T, the phase characteristic of the phase of the sensor output signal is delayed by approximately 90 deg with respect to the phase of the input vibration. By suppressing the resonance of the torque rod T by using the acceleration sensor 4 having, it is possible to reduce the vibration in the resonance region including the peak of the resonance frequency of the torque rod T.

  Further, in the vibration damping device 1 of the present embodiment, the sensor output signal can be treated as the actual speed of the torque rod T by using the phase delay of the acceleration sensor 4, so that the actuator 3 can be current-controlled. Therefore, it is not necessary to adjust the phase with respect to the phase of the sensor output value by a phase lead filter or the like required for voltage control of the actuator 3, the number of differentiating elements when generating the damping command is reduced, and the damping command becomes smooth. As a result, transient voltage command changes in the vibration damping device 1 are suppressed, and noise during vibration damping is reduced. Further, the frequency of the transient current flowing in the vibration damping device 1 also decreases.

  Further, when the voltage of the actuator 3 is controlled, it is necessary to multiply the sensor output signal of the acceleration sensor 4 by a large gain to generate the damping command. However, in the vibration damping device 1 of the present embodiment, since the actuator 3 is current-controlled, the damping command can be generated without multiplying the output value of the acceleration sensor 4 by a large gain. The / N ratio is improved. As a result, in the vibration damping device 1 of the present embodiment, the accuracy of vibration suppression is further improved.

  Further, when the actuator 3 is voltage-controlled, there is a possibility that the vibration when the mover 32 collides in the actuator 3 becomes a voltage command and the vibration does not converge. However, when the actuator 3 such as the vibration damping device 1 of the present embodiment is current-controlled, the PI control makes it difficult for the mover 32 to cause a collision and to sustain the collision.

  Further, in the vibration damping device 1 of the present embodiment, since the actuator 3 is current-controlled, it is possible to perform the control with higher accuracy (higher vibration damping property) as compared with the case where the actuator 3 is voltage-controlled. Further, the current control makes it less likely to be affected by the environment such as heat.

  The vibration damping device of the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention. For example, the configuration of another embodiment can be added to the configuration of one embodiment, and a part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Furthermore, some of the configurations of certain embodiments may be deleted.

  The damping object of the damping device 1 is not limited. Although the damping object of the damping device 1 of the above embodiment is the torque rod T, it may be another damping member such as an engine mount.

  The vibration damping device 1 of the above-described embodiment suppresses resonance of the torque rod, but is not limited to this configuration. The damping target of the vibration damping device 1 may be not the resonance generated in the torque rod T by the vibration input from the engine E or the like, but the vibration itself input from the engine E or the like to the torque rod T (also as the damping target. Good).

  In the vibration damping device 1 of the above embodiment, the actuator 3 is current-controlled, but speed control, position control, or the like may be used.

  The damping command generation unit 51 of the above-described embodiment generates a damping command by applying a high-pass filter to the sensor output signal of the acceleration sensor 4. The phase of the sensor output signal may be adjusted to 90 deg by advancing the phase. In this case, as in the modified example of FIG. 6, when the frequency of the input vibration is around 200 Hz which is the peak of the resonance frequency of the torque rod T, the phase of the sensor output signal is the phase of the input vibration as in the above embodiment. Since this is delayed by about 90 degrees, the accuracy of the vibration suppression control is improved.

  The vibration damping device 1 of the above-described embodiment uses the digital acceleration sensor, but if the acceleration sensor has the same phase characteristics as the phase of the sensor output signal and the phase of the input vibration, a single acceleration sensor is used. It may be an analog acceleration sensor or a combination of an analog acceleration sensor and an A / D converter.

  In the vibration damping device 1 of the above-described embodiment, a linear actuator (reciprocating motor) is applied as the actuator 3, but an electromagnetic actuator, a voice coil motor, or the like may be used as long as it is an actuator suitable for vibration damping control.

  DESCRIPTION OF SYMBOLS 1 ... Damping device, 2 ... Auxiliary mass, 3 ... Excitation part (actuator), 31 ... Shaft, 32 ... Mover, 33 ... Armature, 4 ... Vibration detection part (acceleration sensor), 4a ... Detection element, 5 ... control unit, 51 ... damping command generation unit, 52 ... current control unit, Ca ... automobile, Ch ... vehicle body, E ... engine, G ... damping gain, T ... torque rod

Claims (3)

An auxiliary mass and a vibrating section that reciprocates the auxiliary mass,
A vibration detection unit that detects the vibration of the vibration suppression object,
A control unit that generates a damping command for driving the vibration applying unit based on an output signal of the vibration detecting unit,
The phase of the output signal is delayed by about 90 degrees with respect to the phase of the input vibration of the vibration detection unit.   The phase delay of the output signal with respect to the phase of the input vibration of the vibration detection unit is approximately 90 degrees when the vibration of the vibration suppression target that vibrates at the resonance frequency of the vibration suppression target is detected. The vibration damping device according to claim 1.   The vibration damping device according to claim 1, wherein the vibration unit is current-controlled.

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