JPH1165677A - Method of controlling actuator for electro hydraulic vibrating table and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for controlling the actuator of an electro hydraulic vibrating table which is equipped with a disturbance compensating function for improving the disturbance of an acceleration waveform generated in a electro hydraulic servo actuator, due to the fractional force of the actuator or the wrap of a servo valve or the like. SOLUTION: A speed/frictional data table (D-TBL) 1h for storing the data corresponding to fractional force characteristics generated in an actuator 3 outputs a frictional force signal proportional to a frictional force generated in the actuator 3, according to an acceleration feedback signal 9 obtained by a speed sensor 8 provided in an excitation table T. A fractional force gain (G) 1i adds the frictional force signal outputted from the table (D-TBL) 1h to a deflection signal 1g of a displacement and differential pressure servo loop system, as a compensation signal for improving the disturbance of the acceleration waveform generated in the actuator 3, and obtains a servo valve command voltage 1j.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for controlling an actuator of an electro-hydraulic vibration table applied to an actuator drive control mechanism of an electro-hydraulic vibration table. Further, the present invention relates to an actuator control method and an actuator control device for an electro-hydraulic vibration table in which a disturbance compensation function is added to a displacement / differential pressure servo loop system in an actuator drive control mechanism of the electro-hydraulic vibration table.

[0002]

2. Description of the Related Art A conventional actuator drive control mechanism applied to an actuator drive control mechanism of an electro-hydraulic vibration table uses a command voltage (C / M) 1a input to a control device 1 as shown in FIG. A deviation signal (deviation voltage) 1c proportional to a deviation from a displacement signal (displacement feedback voltage) 1b of the actuator (ACT) 3 obtained from the displacement sensor 5.
Is applied to the servo valve (S / V) 2 and a minor feedback system of the differential pressure based on the differential pressure signal 1 e obtained from the differential pressure pickup sensor 4. In the figure, 1c is a servo gain (G), 1f is a differential pressure feedback gain (G), 1j
Is a servo valve command voltage, 6 is a joint, and 7 is a vibration table.

In a system in which a minor feedback system of differential pressure is added to the displacement loop system according to the conventional configuration as described above, the frictional force in the actuator,
It has not been possible to improve the acceleration waveform distortion (turbulence) generated in the electrohydraulic servo actuator due to the wrap between the spool and the sleeve of the servo valve. In particular, the waveform distortion due to these factors becomes remarkable as a large turbulence when the acceleration reaches the maximum amplitude, and therefore, when the shaking table system is configured using the electro-hydraulic servo actuator, it is targeted. This was a major obstacle in accurately reproducing the acceleration waveform.

[0004]

As described above, in the system according to the prior art in which the minor feedback system of the differential pressure is added to the displacement loop system, the frictional force in the actuator, the lap of the servo valve, etc. It was impossible to improve the resulting acceleration waveform distortion. In particular, the waveform distortion due to these factors becomes remarkable as a large disturbance when the acceleration reaches the maximum amplitude, and therefore, when the shaking table system is configured using the electro-hydraulic servo actuator, the target acceleration waveform is This has been a major obstacle in accurately reproducing.

[0005] The present invention has been made in view of the above circumstances,
An actuator control method and an actuator control device for an electro-hydraulic vibration table having a disturbance compensation function for improving disturbance of an acceleration waveform generated in an electro-hydraulic servo actuator due to frictional force in an actuator, lap of a servo valve, etc. The purpose is to provide.

Further, the present invention generates a compensation signal proportional to the frictional force generated in the actuator using a data map of the frictional force in the actuator, and performs disturbance compensation by adding the signal to a servo command. An object of the present invention is to provide an actuator control method and an actuator control apparatus for an electro-hydraulic vibration table in which distortion of an acceleration waveform generated in an electro-hydraulic servo actuator due to frictional force in an actuator, lap of a servo valve, etc. is improved. And

[0007]

According to the present invention, a speed-frictional force data table equivalent to the frictional force characteristic generated in an actuator is stored in a control device constituting a servo loop system, and the speed at the time of actuator driving time is stored. Calculating frictional force online from the command and the data map on the table above, and adding a voltage signal obtained by multiplying this to the servo loop system consisting of the conventional displacement / differential pressure feedback system It is characterized by.

That is, the present invention relates to a method for controlling an actuator of an electro-hydraulic shaking table, wherein the servo-loop system is provided with a speed-friction force data table corresponding to a friction force characteristic generated in the actuator of the electro-hydraulic shaking table. The present invention is characterized in that disturbance in an acceleration waveform generated in an actuator of an electro-hydraulic shaking table is improved by a disturbance compensation function using the speed-friction force data table.

Further, the present invention relates to an actuator control apparatus for an electro-hydraulic vibration table, wherein an actuator drive control mechanism of the electro-hydraulic vibration table is constituted by a servo loop system of displacement and differential pressure. A speed-friction force data table storing data corresponding to the generated frictional force characteristics; a means for obtaining a speed feedback signal of the shaking table; and a speed-friction force data table based on the speed feedback signal. Means for obtaining a compensation signal proportional to the frictional force generated in the actuator; and means for obtaining a servo valve command signal for the actuator based on the compensation signal and a deviation signal of the servo loop system. And

[0010]

In the shaking table system using the electro-hydraulic servo actuator, the major causes of the acceleration waveform distortion are the friction of the actuator and the lap of the servo valve. Waveform distortions caused by these two factors appear as disturbances at the time of maximum acceleration.

By applying the above-described disturbance compensation function in the electro-hydraulic servo loop system, it becomes possible to increase the drive command to the servo valve near the acceleration peak (near zero speed). It is possible to compensate for the disturbance of the waveform generated at the maximum amplitude.

Further, according to the shaking table system using the electro-hydraulic servo actuator of the present invention, it is possible to improve the acceleration waveform distortion which is inevitably caused by resonance with the frictional force of the actuator and the lap of the servo valve. Therefore, the accuracy of the response signal of the excitation table with respect to the target signal can be improved. This makes it possible to reproduce the acceleration waveform on the vibration table with high accuracy.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a control block diagram of an embodiment according to the present invention. In FIG. 1, 1 is a control device of an electrohydraulic servo actuator, and 2 is a servo valve (S /
V), 3 is an actuator (ACT), 4 is a differential pressure pickup sensor, 5 is a displacement sensor, 6 is a joint, and 7 is a vibration table.

Reference numeral 8 denotes a speed sensor provided on the vibration table 7, and 9 denotes a speed feedback signal obtained from the speed sensor 8. This speed feedback signal 9
Is an input signal (address signal for table index) of a speed-friction force data table 1n described later.

In the controller 1, 1a is a command voltage (C / M), 1b is a displacement signal (displacement feedback voltage) of the actuator (ACT) 3 obtained from the displacement sensor 5, and 1c is a command voltage (C / M). / M) A deviation signal (deviation voltage) proportional to the deviation between 1a and the displacement signal (displacement feedback voltage) 1b, 1d is the differential pressure feedback gain (G), 1e is the differential pressure signal obtained from the differential pressure pickup sensor 4, 1f is a differential pressure feedback gain (G), and 1g is a deviation signal.

Reference numeral 1h denotes a speed-friction force data table (D-TBL) storing data corresponding to the frictional force characteristics generated in the actuator 3, and the vibration table 7
And outputs a frictional force signal proportional to a frictional force generated in the actuator 3 in accordance with the input signal.

Reference numeral 1i denotes a frictional force gain (G) for inputting the frictional force signal output from the speed-frictional force data table (D-TBL) 1h, and the speed-frictional force data table (D-TBL) 1h The frictional force signal thus output is added to the deviation signal 1g of the displacement / differential pressure servo loop system as a compensation signal for improving disturbance of the acceleration waveform generated in the actuator 3, and a servo valve command voltage 1j is obtained.

FIG. 2 is a diagram showing a speed-friction force data map of the speed-friction force data table (D-TBL) 1h. FIG. 3 is a diagram showing the acceleration waveform on the vibration table 7 in the case of the drive control according to the embodiment of the present invention and in the case of the conventional drive control, and FIG. 3A shows the command voltage (C / M).
FIG. 1B shows a signal waveform of FIG. 1A, FIG. 2B shows an acceleration waveform at the time of disturbance compensation according to the embodiment of the present invention, and FIG. 2C shows a conventional acceleration waveform.

The operation according to the embodiment of the present invention will now be described with reference to FIGS. The vibration table 7 is driven by an actuator (ACT) 3 via a joint 6. At this time, the speed feedback signal 9 obtained from the speed sensor 8 provided on the vibration table 7 is input to the speed-friction force data table (D-TBL) 1h.

Speed-friction force data table (D-TB)
L) 1h outputs a friction force signal proportional to the friction force generated in the actuator (ACT) 3 according to the speed feedback signal 9 obtained from the speed sensor 8, and supplies the friction force signal to the friction force gain (G) 1i.

When the frictional force signal output from the speed-frictional force data table (D-TBL) 1h is inputted, the frictional force signal 1i is used to improve the acceleration waveform disturbance generated in the actuator (ACT) 3. A servo valve command voltage 1j is obtained as a compensation signal in addition to the deviation signal 1g of the displacement / differential pressure servo loop system.

As described above, in the embodiment of the present invention, in the shaking table system using the electro-hydraulic actuator, the speed-friction force data table (D-TBL) 1
Using h, a compensation signal proportional to the frictional force of the actuator (ACT) 3 is calculated from the velocity feedback value of the shaking table, and the compensation signal is added to a deviation signal calculated from the displacement / differential pressure servo system to perform servo control. This is a command signal to the valve (S / V) 2. Actuator (ACT) 3 by the command signal
, The distortion caused by the frictional force in the acceleration waveform generated on the vibration table 7 can be improved.

In a fatigue tester in which an electrohydraulic servo actuator is dynamically driven to apply a force to a test piece attached to the tip of the actuator, a highly accurate vibration is applied by applying the same method as described above. The waveform can be reproduced.

[0024]

As described above in detail, according to the present invention, in a shaking table system using an electro-hydraulic servo actuator, a disturbance compensation function using a speed-friction force data table is provided. In this case, it becomes possible to increase the drive command to the servo valve near the acceleration peak (near zero speed), thereby compensating for the waveform disturbance occurring at the maximum acceleration amplitude.

Further, according to the present invention, in a shaking table system using an electro-hydraulic servo actuator, it is possible to improve the acceleration waveform distortion which resonates with the frictional force of the actuator, the lap of the servo valve, etc., and inevitably occurs. Therefore, the accuracy of the response signal of the excitation table with respect to the target signal can be improved. This makes it possible to reproduce the acceleration waveform on the vibration table with high accuracy.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a main part of an actuator drive control mechanism of an electro-hydraulic vibration table according to an embodiment of the present invention.

FIG. 2 is a diagram showing a speed-friction force data map of a speed-friction force data table (D-TBL) 1h in the embodiment.

FIG. 3 is a diagram showing an acceleration waveform on a vibration table 7 in the embodiment in comparison with a conventional acceleration waveform.

FIG. 4 is a block diagram showing a configuration of a main part in a conventional actuator drive control mechanism of an electro-hydraulic vibration table.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Control device of electrohydraulic servo actuator, 2 ... Servo valve (S / V), 3 ... Actuator (ACT), 4 ... Differential pressure pickup sensor, 5 ... Displacement sensor, 6 ... Coupling, 7 ... Vibration table, 8 ... speed sensor 9 ... speed feedback signal 1a: command voltage (C / M), 1b: displacement signal (displacement feedback voltage), 1c: deviation signal (deviation voltage), 1d: differential pressure feedback gain (G), 1e: differential pressure signal, 1f: differential pressure feedback Gain (G), 1g: Deviation signal, 1h: Speed-friction force data table (D-TBL), 1i: Friction force gain (G), 1j: Servo valve command voltage.

Claims (2)

[Claims] An actuator for an electro-hydraulic shaking table stores a speed-friction force data table corresponding to a frictional force characteristic generated in an actuator of the electro-hydraulic shaking table in an actuator control device constituting a servo loop system. Wherein the disturbance of the acceleration waveform generated in the step (c) is improved by a disturbance compensation function using the speed-friction force data table. 2. A frictional force generated in said actuator in an actuator control apparatus for an electro-hydraulic vibration table, wherein said actuator drive control mechanism of said electro-hydraulic vibration table comprises a servo loop system of displacement and differential pressure. A speed-friction force data table storing data according to characteristics; a means for obtaining a speed feedback signal of the shaking table; and a speed-friction force data table generated in the actuator based on the speed feedback signal based on the speed feedback signal. Means for obtaining a compensation signal proportional to the frictional force to be applied, and means for obtaining a servo valve command signal for an actuator based on the compensation signal and a deviation signal of a servo loop system. Actuator control device for vibration table.