JP2003345444A - Position feedback compensating method for redundant actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To rapidly perform a compensating processing when a fault occurs in each system. <P>SOLUTION: The respective kinds of position feedback of the two redundant systems are defined as the stroke burdens L1, L2 of motors 2, 3 in the respective systems, and also defined as the integrated values Ef1, Ef2 of rotation detectors in the respective systems. The position detecting result of a whole stroke L in the redundant actuator 1 is fetched from a potentiometer 4, and defined as the value Ef. The fetched value Ef is compared with the integrated values Ef1, Ef2 of the systems, so as to obtain ratios Gc1, Gc2. The ratios Gc1, Gc2 are multiplied by a position command value Ec with respect to the whole stroke L of the redundant actuator 1. One product is defined as the position command value Ec1 to the one motor 2, and the other product is as the position command value Ec2 to the other motor 3. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for compensating position feedback of a redundant linear actuator used for operating a movable nozzle of a rocket, for example.

[0002]

2. Description of the Related Art Conventionally, as the above-mentioned redundant actuator, for example, there is a redundant linear actuator which includes two motors and is connected such that each output of these two motors is output as a sum of speeds. In this redundant linear actuator, approximately (approximately) 1 /
By performing two strokes at a time, the entire stroke as the actuator is controlled.

In such a redundant linear actuator, in order to perform position servo control, a position detector for detecting the length of an output shaft is arranged, and the amount of displacement in the length direction is detected by the position detector. Feedback is performed, and a plurality of position detectors are arranged in order to provide redundancy for the failure of the position detector.

[0004]

However, in the above-mentioned redundant linear actuator, in order to compensate for the failure of the detector, a plurality of LVDTs (linear variable differential transformers) and potentiometers which can easily detect the failure are arranged. Thus, for example, it is necessary to identify a failure by comparison with a redundant counterpart detector.

Further, when the rotation angle of the motor is detected by a rotation detector such as a resolver or an encoder, and the integrated value is converted into a stroke by calculation, when the position is used as position feedback, quick compensation for the occurrence of a failure is provided. There is a problem that operation cannot be expected, and solving this problem has been a conventional problem.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is capable of instantaneously compensating for the occurrence of a failure in each system. It is intended to provide a way.

[0007]

According to a first aspect of the present invention, there is provided a redundant actuator having two motors, and connecting the motors so as to output the respective outputs of the two motors as a sum of speeds. Position feedback compensation method, wherein the position feedback of each of the two systems is taken as the stroke share L1, L2 of the motor of each system and the integrated value Ef1, Ef2 of the rotation detector of each system, and the total stroke L of the redundant actuator is calculated. The position detection result is converted into a potentiometer, a linear variable differential transformer and the integrated value Ef.
1, Ef2, and is taken as Ef, and this taken value Ef and the integrated values Ef1, Ef of each system are taken as Ef.
Gc1 (= Ef1 / Ef) and Gc2 (= Ef
2 / Ef), the position command value Ec for these ratios Gc1 and Gc2 and the overall stroke L of the redundant actuator.
And the position command value Ec for one of the motors
1 and the position command value Ec for the other motor.
2, and the configuration of the redundant actuator position feedback compensation method is a means for solving the above-described conventional problem.

[0008] In the position feedback compensation method for a redundant actuator according to the second aspect of the present invention, when a failure of a potentiometer or a linear variable differential transformer as a position detector for detecting the position of the entire stroke L of the redundant actuator is detected. Is to quickly fix the ratios Gc1 and Gc2 of the captured value Ef and the integrated values Ef1 and Ef2 of each system to 1/2, and when a failure of the rotation detector of each system is detected, The control is stopped immediately.

In this position feedback compensation method for a redundant actuator, if the reliability of the position detector is low, a plurality of position detectors may be arranged or the integrated value of the motor rotation angle detected by the plurality of redundant motors may be calculated. It is possible to use a sum.

In the position feedback compensation method for a redundant actuator according to the third aspect of the present invention, when a potentiometer is used as the position detector, the output signal terminal from the brush is set to a + voltage or a detection voltage at which the detection signal has a maximum value or more. It is configured to be connected to a voltage with a high resistance that is equal to or less than the minimum value.

[0011]

According to the position feedback compensation method for a redundant actuator according to the first aspect of the present invention, since the above-described configuration is employed, it is not necessary to detect the occurrence of a failure in a redundant partner system, that is, one system. Therefore, it is not necessary to detect the occurrence of a failure in the other system from the other system, or to detect the occurrence of a failure in one system from the other system. In addition, it is not necessary to switch the position command value. The compensation operation for the occurrence of the failure is quickly performed.

In the method of compensating for the position feedback of the redundant actuator according to the second aspect of the present invention, since the above-described configuration is employed, the position detector and the rotation detectors of the respective systems have a system-redundant relationship, and the position detection is performed. This eliminates the need for multiple sensors.Especially for servo systems that provide speed feedback, which requires position and rotation angle detectors, and systems that require rotation angle detection, such as DC brushless motors, additional sensors are required. Can be constructed.

In the position feedback compensation method for a redundant actuator according to the third aspect of the present invention, since the above-described configuration is employed, even in a potentiometer in which failure detection is difficult, a position feedback path is automatically provided to the rotation angle detector when a failure occurs. Will be changed.

[0014]

According to the position feedback compensation method for a redundant actuator according to the first aspect of the present invention, by employing the above-described configuration, it is possible to instantaneously perform a compensation operation with respect to occurrence of a failure in each system. This is a very good effect.

According to the position feedback compensating method for a redundant actuator according to the second aspect of the present invention, since the above-described configuration is employed, it is possible to avoid disposing a plurality of position detectors. For a system that requires angle detection, there is a very excellent effect that the system can be constructed without requiring an additional sensor.

In the method for compensating for the position feedback of the redundant actuator according to the third aspect of the present invention, since the above-described configuration is used, the position feedback path rotates when a failure occurs despite the use of a potentiometer which is difficult to detect the failure. The very good effect is that the angle detector can be changed automatically.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of a position feedback compensation method for a redundant actuator according to the present invention.

As shown in the block diagram of FIG. 1, the redundant actuator 1 includes two systems of motors 2 and 3 connected to each other so as to output each output as a sum of speeds, and a position detecting device for detecting an overall stroke L of the actuator. A potentiometer 4 as a measuring device, an A / D converter 5 for taking in the detection result of the entire actuator stroke L from the potentiometer 4, and a position feedback control unit 6 (part enclosed by a broken line in FIG. 1) for performing position feedback control. I have.

The position feedback control unit 6 uses the position feedback of each of the two systems as the stroke share L1, L2 of the motors 2, 3 of each system and the integrated value Ef1, Ef2 of the rotation detector of each system. Is detected by the A / D converter 5 as a fetched value Ef from the potentiometer 4 and
SP (digital signal process)
or), the ratio Gc1 (= Ef1 / Ef) between the captured value Ef and the integrated values Ef1 and Ef2 of the rotation detectors of each system,
Gc2 (= Ef2 / Ef) is obtained, and these ratios Gc1,
The product of Gc2 and the position command value Ec for the entire stroke L of the redundant actuator is taken as the position command value Ec1 for the motor 2 of one system and the position command value Ec2 for the motor 3 of the other system. ing.

In this case, the position feedback control unit 6 sets the ratio Gc1 to 1/2 ≦ Gc1 ≦ to avoid an unrealistic value due to the influence of noise or error at the time of a small signal.
And clamp the ratio Gc2 to 1/2 ≦ Gc2 ≦
Clamping at 1 and implementing this control system,
The capture value Ef is set to the minimum value in order to prevent “0/0” when the capture value Ef becomes 0.

Therefore, it is assumed that a failure has occurred in the other system in which the motor 3 of the redundant actuator 1 is located. In such a failure, since only one of the systems in which the motor 2 is provided is driven, the amount of change in the stroke L1 of the motor 2 is equal to the amount of change in the entire actuator stroke L, and the ratio Gc1 is 1 (normally Gc1). = 1/2).
Since this operation is a transfer function, it is equivalent to feeding back the captured value Ef.

At this time, since the position command value changes from 1/2 Ec to Ec, the stroke burden L1 in one system where the motor 2 is provided is equal to the total stroke L of the actuator.
Thus, the shortage of stroke at the time of failure is automatically compensated.

As shown in the upper and lower portions of FIG. 2, the position control gain changes equivalently, and automatically becomes equivalent to the gain of the transfer function when the same operation as that of the partner system is performed.

Further, when a failure of the potentiometer 4 as a position detector for detecting the position of the entire stroke L of the redundant actuator 1 is detected, the ratios Gc1 and Gc2 of the fetched value Ef and the integrated values Ef1 and Ef2 of the respective systems. Is quickly fixed to 1/2, the position command value Ec becomes the stroke L1 or L2 corresponding to the burden of one system or the other system, and the total stroke L is compensated as a total.

Further, when the failure of the rotation detector of the redundant actuator 1 is detected, the control of the failed system is immediately stopped, and after the stop, in the normally operating system, a signal from the position detector is output from the position detector. The automatic operation is compensated in the same manner as described above from the change in the fetched value Ef.

The position feedback is provided for compensating the operation of the other system, and is not directly used for the feedback of the servo system. Therefore, it can be deleted in the case of a position detector failure. When the position detector is in a normal state, it is possible to automatically compensate for the failure of the rotation angle detector with the motor of the other system, so that it is not necessary to install a plurality of rotation angle detectors.

Further, when the potentiometer 4 is used as the position detector as in this embodiment, as shown in FIG. 3, the output signal terminal 7 from the brush is set to a positive voltage or a detection voltage which is higher than the maximum detection voltage. It is desirable to connect with a high resistance to the voltage minus the voltage minimum value or less.

In this case, when the potentiometer 4 breaks down and the brush is opened, the voltage is set to the + voltage or the-voltage set by the circuit, and the detection voltage is maximum or minimum by the circuit. When the absolute value is calculated, Gc2 becomes 1/2, that is, the ratio G between the captured value Ef and the integrated values Ef1 and Ef2 of the respective systems.
The above operation of quickly fixing c1 and Gc2 to 1/2 is automatically performed, and as a result, the entire stroke L is compensated.

As described above, in spite of using the potentiometer 4 which is difficult to detect a failure, at the time of a failure, the position feedback path to the rotation angle detector is automatically changed.

In the above-described embodiment, the position detection result of the entire stroke L of the redundant actuator 1 is fetched from the potentiometer 4 as a position detector, and is set as Ef. A differential transformer) can be used, and as shown in the block diagram of FIG. 4, the position detection result of the entire stroke L of the redundant actuator 1 is obtained from the sum of the rotation detector integrated values Ef1 and Ef2 of each system. It can be taken in.

The position feedback compensation method of the redundant actuator according to the present invention can be employed for position feedback compensation of the redundant actuator used for operating the movable nozzle of the rocket. It can be used for position feedback compensation of a hatch driving actuator.

The detailed configuration of the redundant actuator position feedback compensation method according to the present invention is not limited to the above-described embodiment.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a redundant actuator position feedback compensation method according to the present invention.

FIG. 2 is a block diagram showing that a position control gain by a position feedback compensation method (processing method) in FIG. 1 is automatically equivalent to a gain of a transfer function when the same operation as that of a partner system is performed.

FIG. 3 is a partial circuit diagram showing an optimal embodiment when a potentiometer is used as a position detector in the position feedback compensation method in FIG.

FIG. 4 is a block diagram showing another embodiment of the redundant actuator position feedback compensation method according to the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 redundant actuator 2 one system motor 3 the other system motor 4 potentiometer (position detector) 6 position feedback control unit 7 output signal terminal Ec position command values Ec1 and Ec2 for overall stroke Position command values Ef for motors in each system Captured values Ef1 and Ef2 of position detection results of entire strokes Integrated values (rotation angle integrated values) of rotation detectors of each system Gc1, Gc2 Ratio of captured value and integrated value of each system Kp Servo controller gain L Redundant actuator Total stroke L1, L2 Stroke share of motor of each system

Claims (3)

[Claims] 1. A position feedback compensation method for a redundant actuator comprising two motors and connecting the motors so as to output the respective outputs of the two motors as a sum of speeds, comprising: The feedback is defined as the stroke share L1, L2 of the motor of each system and the integrated value Ef1, Ef2 of the rotation detector of each system, and the position detection result of the entire stroke L of the redundant actuator is determined by a potentiometer, a linear variable differential transformer, Fetched from one of the sums of the values Ef1 and Ef2 and
f, the input value Ef and the integrated value Ef of each system
Gc1 and Gc2 with respect to Ef1 and Ef2.
A redundant actuator characterized by taking a product of c1 and Gc2 and a position command value Ec for the entire redundant actuator stroke L to obtain a position command value Ec1 for one motor and a position command value Ec2 for the other motor. Position feedback compensation method. 2. The overall stroke L of the redundant actuator.
If the failure of a potentiometer or linear variable differential transformer as a position detector that detects the position of
The ratios Gc1 and Gc2 of the captured value Ef and the integrated values Ef1 and Ef2 of each system are fixed to 1/2 quickly, and when a failure of the rotation detector of each system is detected, control of the failed system is performed. 2. The method according to claim 1, wherein the stop is performed promptly. 3. When a potentiometer is used as the position detector, an output signal terminal from the brush is connected with a high resistance to a positive voltage that is equal to or higher than the maximum detection voltage or a negative voltage that is equal to or lower than the minimum detection voltage. 3. The position feedback compensation method for a redundant actuator according to 1 or 2.