JP2001265405A - Multiple system servo actuator controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multiple system servo actuator controller capable of preventing the deterioration of responsiveness or servo rigidity as much as possible and preventing power waste due to any antagonization between systems. SOLUTION: This multiple system servo actuator controller is constituted of a control circuit 20 for controlling the first system of an electric servo actuator 1, a control circuit 30 for controlling the second system of the electric servo actuator 1, and a serial bus 40 for operating data communication between the control circuits 20 and 30. The control circuits 20 and 30 are respectively constituted of CPUs 21 and 31, memories 23 and 33, input and output circuits 24 and 34, driver circuits 25 and 35 for outputting motor driving currents to motor coils 9a and 9b of a monitor 10, communication I/F circuits 26 and 36 for operating data communication with a host controller 41, and inter-system communication I/F circuits 27 and 37 for operating data communication with the other system. Deflection characteristics between a sensor signal S1 and a sensor signal S2 are measured, and dead zone width W1 and W2 of amplifiers 61 and 71 of the control circuits 20 and 30 are respectively controlled based on the measured deflection characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo actuator control device in which an electric circuit system is juxtaposed to form a multiplex system.

[0002]

2. Description of the Related Art For example, in a FBW (fly-by-wire) helicopter, an aircraft, a spacecraft, or the like, a plurality of drive systems for controlling the same control target are provided in parallel, and even if some of the drive systems fail, the remaining drive systems remain. The safety and reliability are improved by configuring the multiplex system so that normal operation can be continued only by the system.

[0003]

The multi-system servo actuator has high reliability, but the actuator driving force is slightly different between the systems due to variations among the systems such as control circuits, sensors and drive circuits. As a result, the responsiveness is degraded and power is wasted due to antagonism between systems. In particular, power waste that does not contribute to the output becomes remarkable when outputs having different polarities occur between the systems. When outputs of the same polarity and different magnitudes are generated between the systems, the torque and force act additively, so that the power is effectively used. However, when outputs having different polarities are generated between the systems, the torque and the force cancel each other, and power is wasted.

[0004] As a countermeasure, control circuits of each system,
It is conceivable to drive in with fine adjustment so that variations in sensor signal values, drive circuits, and the like are minimized. However, once the control unit has been adjusted, it becomes a matched set that is limited to only the combination with that actuator,
Subsequent maintenance and replacement become difficult.

As another countermeasure, for example, a method of communicating operation output signal values of respective systems with each other, calculating an average value or a median value of operation signal values, and using a common operation output signal value in each system is considered. (For example, Japanese Patent Laid-Open No. 9-126)
351 and JP-A-58-139202). However, an average value calculation circuit and a median value calculation circuit that refer to the cross-links between the systems are required, which weakens the independence between the systems and complicates the control circuit.

SUMMARY OF THE INVENTION An object of the present invention is to provide a multiplex servo actuator control device capable of preventing power waste due to antagonism between systems while minimizing a decrease in responsiveness and servo stiffness.

[0007]

SUMMARY OF THE INVENTION The present invention provides a first drive unit and a second drive unit for independently driving an actuator, and independently detects motion information of the actuator to obtain a first detection signal and a second detection signal. And a first sensor for outputting a first operation signal to the first drive unit by performing a servo control operation so that a difference between the external command signal and the first detection signal is reduced. A control operation unit, a second control operation unit that performs a servo control operation so as to reduce a difference between the external command signal and the second detection signal, and outputs a second operation signal to the second drive unit; A first control characteristic adjustment unit for measuring a deviation characteristic between the signal and the second detection signal, and adjusting a control characteristic of the first control calculation unit based on the measured deviation characteristic; Measuring a deviation characteristic between the two detection signals, Is a multi-system servo actuator control device characterized by comprising a second control characteristic adjustment unit for adjusting the control characteristics of the second control arithmetic unit on the basis of the boss was deviation characteristics.

According to the present invention, a deviation characteristic between a first detection signal and a second detection signal is measured in a multiplex servo actuator in which a first driving unit and a second driving unit independently drive a common actuator. Then, by adjusting the control characteristics of the first control calculation unit and the second control calculation unit based on the measured deviation characteristics, the antagonistic state between the systems can be reduced.

Incidentally, as the motion information of the actuator and the external command signal, displacement information, speed information, acceleration information and the like can be used according to the target of the servo control.

Further, according to the present invention, a first drive unit and a second drive unit for independently driving an actuator, and an output displacement of the actuator are independently detected, and a first detection signal and a second detection signal are output.
Servo control calculation is performed so that the difference between the external command signal and the first detection signal is reduced, and the first operation signal is output to the first sensor and the second sensor that respectively output the detection signals.
A first control calculation unit that outputs to the drive unit, and a second control that performs servo control calculation so as to reduce the difference between the external command signal and the second detection signal, and outputs a second operation signal to the second drive unit. An arithmetic unit, a first control characteristic adjusting unit for measuring a deviation characteristic between the first detection signal and the second detection signal, and adjusting a control characteristic of the first control arithmetic unit based on the measured deviation characteristic; And a second control characteristic adjustment unit for measuring a deviation characteristic between the first detection signal and the second detection signal and adjusting a control characteristic of the second control calculation unit based on the measured deviation characteristic. A multiplex servo actuator control device characterized by the following.

According to the present invention, a deviation characteristic between a first detection signal and a second detection signal is measured in a multiplex servo actuator in which a first driving unit and a second driving unit independently drive a common actuator. Then, by adjusting the control characteristics of the first control calculation unit and the second control calculation unit based on the measured deviation characteristics, the antagonistic state between the systems can be reduced.

Further, according to the present invention, the control characteristic of the first control operation section has a dead zone of the width W1 and the gain G1a, has a higher gain G1b than the gain G1a except for the dead zone, and has a control characteristic of the second control operation section. Is the width W2 and the gain G2a
The first control characteristic adjustment unit and the second control characteristic adjustment unit have a first control operation unit and a second control operation unit based on the measured deviation characteristic. It is characterized in that the dead zone widths W1 and W2 of the calculation unit are variably set.

According to the present invention, the dead zone width W of the first control calculation unit and the second control calculation unit is determined based on the measured deviation characteristics.
1 and W2 are variably set, so that the first
When the deviation characteristic between the detection signal and the second detection signal is large, the control gain in the antagonistic state is reduced by increasing the dead zone widths W1 and W2, so that power consumption in the actuator can be prevented. On the other hand, when the deviation characteristic between the first detection signal and the second detection signal is small, the responsiveness and the servo stiffness in the normal operation can be maintained high by narrowing the dead zone widths W1 and W2.

Further, according to the present invention, the first control characteristic adjusting section and the second control characteristic adjusting section measure a deviation characteristic between the first detection signal and the second detection signal over an operation range of the actuator, and It is characterized in that a constant evaluation value is calculated by the processing, and the dead zone widths W1 and W2 of the first control operation unit and the second control operation unit are adjusted based on the evaluation value.

According to the present invention, a deviation characteristic between the first detection signal and the second detection signal is measured over the operating range of the actuator, and a constant evaluation value is calculated by statistical processing.
By adjusting the dead zone widths W1 and W2 based on the evaluation values, the antagonistic state can be reliably reduced regardless of the operating range of the actuator.

Further, according to the present invention, the first control characteristic adjusting unit and the second control characteristic adjusting unit store the deviation characteristic between the first detection signal and the second detection signal in advance and store the deviation characteristic between the first detection signal and the second detection signal. The adjustment unit adjusts the dead zone width W1 of the first control operation unit in real time based on the deviation value corresponding to the current first detection signal, and the second control characteristic adjustment unit adjusts the deviation corresponding to the current second detection signal. The dead zone width W2 of the second control calculation unit is adjusted in real time based on the value.

According to the present invention, the deviation characteristic between the first detection signal and the second detection signal is stored in advance, and the first control characteristic adjustment unit stores the deviation value corresponding to the current first detection signal. By adjusting the dead zone width W1 of the first control calculation unit in real time based on the above, the antagonistic state can be reliably reduced regardless of the operating range of the actuator. Also, in the region where the deviation characteristic is small in the operation range of the actuator,
By reducing the dead zone width W1, the response and the servo rigidity in this region can be kept high.

Similarly, the second control characteristic adjustment unit is configured to control the current second
By adjusting the dead zone width W2 of the second control calculation unit in real time based on the deviation value corresponding to the detection signal,
The antagonistic state can be reliably reduced regardless of the operation range of the actuator. In a region where the deviation characteristic is small in the operation range of the actuator, the responsiveness and the servo stiffness in this region can be maintained high by narrowing the dead zone width W2.

Further, the first control characteristic adjustment section and the second control characteristic adjustment section can adjust their own dead band widths based on the stored information only by the detection signal of the own system, so that the independence between the systems can be enhanced. it can.

[0020]

FIG. 1 is a sectional view showing an example of a multiplex servo actuator to which the present invention can be applied. The electric servo actuator 1 drives one ball screw 6 to rotate by a motor 10 of a dual circuit system, and
Is moved linearly to control the position of the output shaft 4.

The ball screw 6 is rotatably supported by a bearing 7 with respect to the housing 2 and the fixed portion 3. Ball screw 6
The magnets 8a and 8b serving as the rotor of the motor 10 are attached to the base of the motor 2, and the magnets 8a and 8b
The motor coils 9a and 9b are attached so as to surround.

A nut 5 fixed to the output shaft 4 is screwed into the ball screw 6. The output shaft 4 is slidably supported on the housing 2, and the rotation is restricted by the rotation stopper 15. The two sensing members 12a and 12b are integrally attached in parallel with the output shaft 4. Inside the housing 2, two displacement sensors 11a and 11b for independently detecting the displacement of each of the sensing members 12a and 12b are attached.

Thus, the motor 10 and the displacement sensor 11
a and 11b constitute a double circuit system. If the first system circuit fails, the first system failure is detected and appropriate action is taken to perform servo operation only with the second system circuit. Can be continued, so that the overall reliability can be improved.

FIG. 2 is a block diagram showing an electrical configuration of an embodiment of the present invention. The servo actuator control device includes a control circuit 20 for controlling a first system of the electric servo actuator 1, a control circuit 30 for controlling a second system of the electric servo actuator 1, and control circuits 20, 30.
And a serial bus 40 for performing data communication between them. The host controller 41 performs data communication with the control circuits 20 and 30 via the other serial buses 38 and 39, and sends the same external command signal to the control circuits 20 and 30, for example.

The control circuit 20 has a CPU (Central Processing Unit) 21 for controlling the entire operation according to a predetermined program.
, A memory 23 for storing programs and data, and an input / output circuit (Programmable Input
d Output) 24, a driver circuit 25 that outputs a motor drive current to the motor coil 9a of the motor 10, a communication I / F (interface) circuit 26 that performs data communication with the host controller 41, and a control circuit 30. , And an inter-system communication I / F circuit 27 for performing data communication. CP
U21 is a register 22 which is a work memory for arithmetic processing.
Having. Further, the sensor signal from the displacement sensor 11a is taken into the input / output circuit 24.

The control circuit 30 is, like the control circuit 20,
CPU that controls the overall operation according to a predetermined program
31, a memory 33 for storing programs and data,
An input / output circuit 34 for inputting / outputting data;
A driver circuit 35 for outputting a motor drive current to the motor coil 9b, a communication I / F circuit 36 for performing data communication with the host controller 41, and an inter-system communication I / F circuit for performing data communication with the control circuit 20 37 and the like.
The CPU 31 has a register 32 which is a work memory for arithmetic processing. The sensor signal from the displacement sensor 11b is taken into the input / output circuit 34.

FIG. 3 is a control block diagram showing the operation of the control circuits 20 and 30. The control circuit 20 includes a subtracter 60 for subtracting the sensor signal S1 from the displacement sensor 11a from the external command signal C, an amplifier 61 for amplifying the output ΔC1 of the subtractor 60, and a current command I
A subtractor 63 for subtracting the amount of current feedback signal of the current output from the driver circuit 25 from 1 and a subtractor 6
3 comprises an amplifier 64 for amplifying the output.

The control circuit 30 is, like the control circuit 20,
A subtractor 70 for subtracting the sensor signal S2 from the displacement sensor 11b from the external command signal C, and an output Δ of the subtractor 70
An amplifier 71 for amplifying C2; a subtractor 73 for subtracting a current feedback signal amount of a current output from the driver circuit 25 from a current command I2 output from the amplifier 71; and an amplifier 74 for amplifying an output of the subtractor 73 Etc.

The torque from the motor output 66 and the torque from the motor output 76 are added, integrated and converted into a motor speed, and the motor speed is integrated and converted into the position of the output shaft 4. The motor speed is converted into a back electromotive voltage by a coefficient KE. In the integrators 52 and 53, s is a Laplace operator, and a and b are constants.

The amplifier 61 functions as a proportional element, and its control characteristic has a dead zone of width W1 and gain G1a.
Outside the dead zone, the gain G1b is higher than the gain G1a. The control characteristic adjustment unit 62 measures a deviation characteristic between the sensor signal S1 and the sensor signal S2, and variably sets the dead zone width W1 of the amplifier 61 based on the measured deviation characteristic.

Similarly, the amplifier 71 functions as a proportional element, and its control characteristic has a dead zone of the width W2 and the gain G2a, and the gain G is higher than the gain G2a except for the dead zone.
2b. The control characteristic adjustment unit 72 determines whether the sensor signal S1
And the sensor signal S2 are measured, and the dead zone width W1 of the amplifier 71 is variably set based on the measured deviation characteristic.

FIG. 4 is a control block diagram showing the operations of the amplifiers 61 and 71 and the control characteristic adjusting units 62 and 72.
The control characteristic adjusting unit 62 includes the sensor signal S1 and the sensor signal S
2, the amplifier 61 is set to the gain G1a if the deviation is within the dead band width W1, and the amplifier 61 is set to the gain G1b if the deviation is outside the dead band width W1.
Set to. In the operating state after the setting is performed, the amplifier 61 performs the servo control operation based on the set gain, and outputs the current command I1 as the operation output signal.

Similarly, the control characteristic adjusting section 72 reads out the amount of deviation between the sensor signal S1 and the sensor signal S2, and if the amount of deviation is within the dead band width W2, changes the amplifier 71 to the gain G2a.
On the other hand, if the shift amount is outside the dead zone width W2, the amplifier 71 is set to the gain G1b. In the operating state after the setting is performed, the amplifier 71 performs the servo control operation based on the set gain, and outputs the current command I2 as the operation output signal.

FIG. 5 is an explanatory diagram showing an example of the operation of the control characteristic adjusting sections 62 and 72. FIG. 5A shows the sensor signal S1.
5B is a graph showing a deviation amount (S1-S2) between the sensor signal S1 and the sensor signal S2 with respect to FIG.
FIG. 5C is a graph showing the initial control characteristics of the amplifier 71.
5 is a graph showing initial control characteristics of the present invention.

The initial control characteristic of the amplifier 61 has a relatively wide dead zone of width W1 with respect to the servo deviation ΔC1. Therefore, even if the servo deviation ΔC1 is large to some extent, if it is within the dead zone, the servo gain becomes low, and the antagonistic state between the systems can be alleviated. However, the responsiveness and the servo stiffness are reduced by the larger dead zone width W1.

The initial control characteristic of the amplifier 71 has a relatively narrow width W2 with respect to the servo deviation ΔC1. Therefore, the responsiveness and the servo rigidity are improved as compared with the amplifier 61, but the servo deviation ΔC2 tends to be outside the dead zone, and the antagonistic state between the systems is maintained.

Therefore, before the normal servo operation is started, the actuator is gradually displaced so that the sensor signal S
When the deviation amount (S1-S2) between 1 and the sensor signal S2 is measured over the operating range of the actuator, the deviation data shown in FIG. 5A is obtained. Next, statistical processing is performed on the deviation data to calculate a certain evaluation value, and the result is stored in a memory or the like. Note that the maximum value of the deviation amount, the root mean square value, or the like can be adopted as the evaluation value.

Next, the dead zone widths W1, W of the amplifiers 61, 71
2 is adjusted to substantially match the evaluation value. Thereafter, when the normal servo operation is started, the dead zone widths W1 and W2 are optimized, so that the antagonistic state between the systems is relaxed,
High responsiveness and high servo rigidity can be maintained.

Next, another operation example of the control characteristic adjusting units 62 and 72 will be described. As described above, before starting the normal servo operation, gradually displace the actuator,
The amount of deviation between the sensor signal S1 and the sensor signal S2 (S1-S
When 2) is measured over the operating range of the actuator,
The deviation data shown in FIG. 5A is obtained, and the deviation data is stored in a memory or the like as a lookup table. Note that the deviation data may be approximated by a predetermined function and stored as an operation parameter for calculating by a function operation.

Thereafter, a normal servo operation is started, and the control characteristic adjusting section 62 reads a deviation value corresponding to the current sensor signal S1 by referring to a look-up table or calculating a function, and determines the dead zone width W1 of the amplifier 61 by this deviation. Adjust in real time to approximately match the value. Therefore,
The dead zone width W1 changes in real time according to the operating position of the actuator.

Similarly, the control characteristic adjusting section 72 also refers to the look-up table and calculates the current sensor signal S
2 is read, and the dead zone width W2 of the amplifier 71 is adjusted in real time so as to substantially coincide with the deviation value. Therefore, the dead zone width W2 changes in real time according to the operating position of the actuator.

In this manner, the dead zone widths W1 and W2 are optimized in real time, and the response and the servo stiffness can be maintained high while alleviating the antagonistic state between the systems. In addition, the control characteristic adjustment units 62 and 72 can adjust their own dead band widths only with the sensor signals of the own system based on the stored data, so that the independence between the systems can be enhanced.

FIG. 6 is a graph showing the control characteristics of the amplifiers 61 and 71. The horizontal axis represents the servo deviations ΔC1 and ΔC2 input to the amplifiers 61 and 71, and the vertical axis represents the amplifiers 61 and 71.
Commands I1 and I2 output as operation output signals
It is.

In the stationary state before the start of the servo operation, Δ
When C1 = x3 and ΔC2 = x4, ΔC1, ΔC2
Enters the dead zone of the amplifiers 61 and 71,
The gain of the current commands I1, I2
And the power consumption of the motor 10 is reduced. In this case, the thresholds WL and WU of the dead zone are adjusted, and WL = x3, W
By setting U = x4, responsiveness and servo rigidity can be further improved.

When ΔC1 = x1 and ΔC2 = x6 in the stationary state before the start of the servo operation, ΔC1,
ΔC2 is outside the dead zone of the amplifiers 61 and 71 and the amplifier 6
The gain of the current commands I1, I1
2 increases, and the power consumption of the motor 10 increases. In this case, the threshold value of the dead zone WU is x6, and the threshold value WL is WL = x
By setting to 1, the current commands I1 and I2 are reduced and the power consumption of the motor 10 can be reduced.

If ΔC1 = x5 and ΔC2 = x3 in the stationary state before the servo operation starts, ΔC1,
Since ΔC2 falls within the dead zone of the amplifier 61, the amplifier 61
Gain decreases, and the current commands I1 and I2 also decrease. XL = x by adjusting the threshold WL and the threshold WU of the dead zone
3. By setting WU = x6, the responsiveness and the servo stiffness are improved while the current command I2 keeps the reduced state of I2.

[0047]

As described in detail above, according to the present invention, in a multiplex servo actuator in which a first drive unit and a second drive unit independently drive a common actuator, a first detection signal and a second detection signal are used. Measure the deviation characteristic between
The first control calculation unit and the second control
By adjusting the control characteristics of the control calculation unit, the antagonistic state between the systems can be reduced. As a result, it is possible to prevent power waste due to antagonism between systems while minimizing a decrease in responsiveness and servo stiffness.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a multiplex servo actuator to which the present invention can be applied.

FIG. 2 is a block diagram illustrating an electrical configuration according to an embodiment of the present invention.

FIG. 3 is a control block diagram showing operations of control circuits 20 and 30.

FIG. 4 shows amplifiers 61 and 71 and a control characteristic adjusting unit 62;
FIG. 72 is a control block diagram showing the operation of the embodiment 72.

5A and 5B are explanatory diagrams illustrating an example of the operation of the control characteristic adjustment units 62 and 72. FIG. 5A illustrates a shift amount (S1-S) between the sensor signal S1 and the sensor signal S2 with respect to the sensor signal S1.
5B is a graph showing the initial control characteristic of the amplifier 61, and FIG. 5C is a graph showing the initial control characteristic of the amplifier 71.

FIG. 6 is a graph showing control characteristics of the amplifiers 61 and 71.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric servo actuator 4 Output shaft 5 Nut 6 Ball screw 8a, 8b Magnet 9a, 9b Motor coil 10 Motor 11a, 11b Displacement sensor 20, 30 Control circuit 21, 31 CPU 26, 36 Communication I / F circuit 27, 37 Communication between systems I / F circuit 38, 39, 40 Serial bus 41 Host controller

Continued on the front page F term (reference) 5H004 GA02 GA40 GB13 GB20 HA07 HB07 JA03 JB08 KA45 KA65 KB02 KC32 LB03 5H209 AA09 BB08 CC01 DD02 DD03 DD04 DD05 SS01 SS05 SS07 9A001 HH34 KZ32 LL02

Claims (5)

[Claims] A first drive unit and a second drive unit that independently drive an actuator, a first sensor that independently detects motion information of the actuator, and outputs a first detection signal and a second detection signal, respectively; A second sensor, a first control calculation unit that performs a servo control calculation so as to reduce a difference between the external command signal and the first detection signal, and outputs a first operation signal to the first drive unit; A second control calculation unit that performs a servo control calculation so as to reduce the difference between the first detection signal and the second detection signal, and outputs a second operation signal to the second drive unit. A first control characteristic adjustment unit for measuring a deviation characteristic between the first and second control signals, and adjusting a control characteristic of the first control calculation unit based on the measured deviation characteristic; and a deviation between the first detection signal and the second detection signal. Measure the characteristics, and based on the measured deviation characteristics, Te multiplexing system servo actuator control device characterized by comprising a second control characteristic adjustment unit for adjusting the control characteristics of the second control arithmetic unit. 2. A first drive unit and a second drive unit that independently drive an actuator, a first sensor that independently detects an output displacement of the actuator, and outputs a first detection signal and a second detection signal, respectively. A second sensor, a first control calculation unit that performs a servo control calculation so as to reduce a difference between the external command signal and the first detection signal, and outputs a first operation signal to the first drive unit; A second control calculation unit that performs a servo control calculation so as to reduce the difference between the first detection signal and the second detection signal, and outputs a second operation signal to the second drive unit. A first control characteristic adjustment unit for measuring a deviation characteristic between the first and second control signals, and adjusting a control characteristic of the first control calculation unit based on the measured deviation characteristic; and a deviation between the first detection signal and the second detection signal. Measure the characteristics, and based on the measured deviation characteristics, Te multiplexing system servo actuator control device characterized by comprising a second control characteristic adjustment unit for adjusting the control characteristics of the second control arithmetic unit. 3. The control characteristic of the first control operation unit has a dead zone of the width W1 and the gain G1a, and has a gain G1b higher than the gain G1a except for the dead zone. W2 and gain G2
a, and has a gain G2b higher than the gain G2a in other than the dead zone. The first control characteristic adjustment unit and the second control characteristic adjustment unit perform the first control calculation unit and the second control characteristic adjustment based on the measured deviation characteristic. 3. The multiplex servo actuator control device according to claim 1, wherein the dead zone widths W1 and W2 of the control calculation unit are variably set. 4. A first control characteristic adjuster and a second control characteristic adjuster measure a deviation characteristic between the first detection signal and the second detection signal over an operation range of the actuator, and keep the constant by statistical processing. Is calculated, and the dead zone widths W1 and W1 of the first control operation unit and the second control operation unit are calculated based on the evaluation values.
4. The multiplex servo actuator control device according to claim 3, wherein W2 is adjusted respectively. 5. The first control characteristic adjustment unit and the second control characteristic adjustment unit store a deviation characteristic between the first detection signal and the second detection signal in advance, and the first control characteristic adjustment unit The dead zone width W1 of the first control calculation unit is adjusted in real time based on the deviation value corresponding to the current first detection signal, and the second control characteristic adjustment unit is adjusted based on the deviation value corresponding to the current second detection signal. 4. The multiplex servo actuator control device according to claim 3, wherein the dead zone width W2 of the second control calculation unit is adjusted in real time.