JPH06180602A - Non-linear system controller - Google Patents

Abstract

PURPOSE:To remove the influence of a cross talk even when the number of parameters is increased, or a frequency is limited by shifting a phase by specific amounts when a superimposed frequency is matched with the high frequency, sum frequency, or difference frequency of the other superimposed frequency, or the other superimposed frequency itself. CONSTITUTION:When the high frequency, sum frequency, or difference frequency of the superimposed frequency generated by an oscillator 31 of the other parameter control part 3 is substantially matched with the output of the oscillator 31, and a cross talk frequency is generated, the phase of a fine vibration generated by its own oscillator 31 is shifted by pi/2 or the odd number-fold length against the phase of the cross talk frequency by a phase adjusting equipment 36. An error signal generating part 2 is a plural input constitution because an object to be controlled is a neural network 11, and it is equipped with plural circuits constituted of a subtracter 21 and squaring circuit 22, and an adder 23 which adds the outputs of those circuits. Therefore, direct components at the time of multiplying signals are turned to zero, and the influence of the cross talk can be removed.

Description

Detailed Description of the Invention

[0001]

The present invention is used for controlling a system having a nonlinear input / output characteristic, for example, a nonlinear circuit. In particular, it relates to the expansion of the frequency range of minute vibrations used for control of nonlinear systems.

[0002]

2. Description of the Related Art FIG. 11 is a block diagram showing a conventional non-linear control device. In this example, a case where the nonlinear circuit 10 is controlled as a nonlinear system will be described.

This non-linear system controller inputs the output of the non-linear circuit 10 to be controlled into one of the error signal generators 20 having two inputs. The reference signal is supplied to the other input of the error signal generator 20. Error signal generator 2
The output of 0 is supplied to each of the plurality of parameter control units 30. The outputs of these parameter control units 30 are
Each is connected to a parameter control input of the non-linear circuit 10.

FIG. 12 is a block diagram showing the details of the error signal generator 20.

The error signal generator 20 comprises a subtractor 21 and a squaring circuit 22. The subtractor 21 subtracts the output of the nonlinear circuit 10 and the reference signal, and the squaring circuit 22 squares the subtraction result. This squared value is the parameter control unit 3
It is output to 0.

FIG. 13 is a block diagram showing the details of the parameter control unit 30.

The parameter control unit 30 includes an oscillator 31, a multiplier 32, a low pass filter 33, and an integrator 34, respectively.
And an adder 35. The signal from the error signal generator 20 is supplied to one input of the multiplier 32,
The output of the oscillator 31 is supplied to the other input of the.
The output of the multiplier 32 is supplied to the integrator 34 via the low-pass filter 33, and the output of the oscillator 31 is added to the output of the integrator 34 by the adder 35. The output of the adder 35 is supplied to the nonlinear circuit 10.

Therefore, the output of the oscillator 31 is supplied to the nonlinear circuit 10 as a minute vibration, and the influence of the parameter control unit 30 can be known from the minute vibration component contained in the error signal of the nonlinear circuit 10. This will be described in more detail with reference to FIG.

FIG. 14 is a diagram for explaining the operation of this conventional example. Here, two parameter control units 30a and 30b
Will be described as an example.

Control signals from the parameter control units 30a and 30b are added to the parameter control input of the nonlinear circuit 10. The control signal from the parameter control unit 30a is the sum of the small vibration output from the oscillator 31a and the output from the integrator 34a, and the control signal from the parameter control unit 30b is the small vibration output from the oscillator 31b and the output from the integrator 34b. Is the sum of Therefore, the two minute vibration components are input to the nonlinear circuit 10.

In the error signal generator 20, the subtractor 21 compares the reference signal with the output of the non-linear circuit 10 and outputs the difference to the squaring circuit 22. The squaring circuit 22 takes the square of the input value and outputs it as an error signal. The error signal includes a vibration component controlled by the parameter control unit 30a and a vibration component controlled by the parameter control unit 30b.

In the parameter control unit 30a, the multiplier 32
As a result, the error signal from the error signal generator 20 is converted into the oscillator 3
Synchronous detection is performed by multiplying the output of 1. When this detection output is passed through the low pass filter 33, a DC component appears in the output. This DC component is integrated by the integrator 34. The output of the integrator 34 is combined with the minute vibration from the oscillator 31 by the adder 35 and supplied to the nonlinear circuit 10 as a control signal. In this way, the optimum value of the control signal to be output by the parameter control unit 30a is obtained.

The parameter control unit 30b also performs the same operation to obtain the optimum value of the control signal to be output.

[0014]

However, in the conventional non-linear system control device, due to the non-linearity of the control system to be controlled, crosstalk between the superposed small vibration and its harmonics, sum frequency and difference frequency is caused. There was a problem that occurs.
Further, due to this crosstalk, the influence of other minute vibrations on the error is mixed in the synchronous detection output, and there is a problem that the controllability of the parameters is reduced.

In order to avoid the above-mentioned crosstalk,
The frequency range of superposed small vibrations must be within an octave, that is, within twice the lowest frequency. However, if you need to increase the number of parameters,
It may be insufficient when the usable frequency is limited.

An object of the present invention is to solve the above problems and to provide a non-linear system control device capable of eliminating the influence of crosstalk even when the number of parameters is increased or the frequency is limited.

[0017]

According to a first aspect of the present invention, a plurality of parameter control units that respectively provide control signals to a control target whose input / output characteristics are nonlinear, and an error for obtaining an output error of the control target. A plurality of parameter control units, each of which includes a vibration superimposing unit that superimposes microvibrations of different frequencies on the output control signal, and a microvibration included in the output error obtained by the error signal generation unit. In a non-linear system control device including a means for detecting a frequency component and an integrating means for integrating the output of the detecting means into an output control signal of the parameter control unit,
When the vibration superimposing means has a crosstalk frequency when any of the harmonic, sum frequency, or difference frequency of the superimposing frequency generated by the vibration superimposing means of the other parameter control unit substantially coincides with the superimposing frequency and becomes the crosstalk frequency. , The phase of the microvibration generated by itself with respect to the phase of the crosstalk frequency is π /
There is provided a non-linear system control device characterized in that it includes a phase adjusting means for shifting by 2 or an odd multiple thereof.

According to a second aspect of the present invention, it is provided with a plurality of parameter control units that respectively provide control signals to a control target whose input / output characteristics are non-linear, and an error signal generating unit that determines an output error of the control target. , Each of the plurality of parameter control units, a vibration superimposing unit that superimposes a microvibration on the output control signal, and a unit that detects the frequency component of the microvibration included in the output error obtained by the error signal generating unit,
In the non-linear system control device including an integrating means for integrating the output of the detecting means to obtain an output control signal of the parameter control section, the vibration superimposing means uses another vibration superimposing means that uses substantially the same frequency. There is provided a non-linear system controller characterized by including a phase adjusting means for shifting the phase of the minute vibration generated by itself with respect to the phase of the minute vibration generated by π / 2 or an odd multiple thereof.

[0019]

Function: A phase difference of π / 2 or an odd multiple thereof is given between signals causing crosstalk. By doing so, the DC component becomes zero when the signals are multiplied, and the influence of crosstalk can be removed. Therefore, there is no limitation on the frequency range of superposed minute vibrations, and the number of controllable parameters can be increased.

It is also possible that the two vibration superposing means can use the same frequency, and a phase difference of π / 2 or an odd multiple thereof can be provided between them. Also in this case, the DC component becomes zero when the signals are multiplied, and crosstalk does not occur. This is effective when the range of the superposed frequency is limited, and the number of controllable parameters can be doubled to the conventional one.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing a non-linear system controller according to a first embodiment of the present invention. Here, a case where a neural network is a control target will be described as an example.

In this embodiment, a plurality of parameter control units 3 which give control signals to a control target whose input / output characteristics are non-linear, that is, a neural network 11, and an error signal generation for obtaining an output error of the neural network 11. And part 2. Each of the parameter control units 3 includes an oscillator 31 and an adder 35 as vibration superimposing means that superimposes minute vibrations of different frequencies on the output control signal, and a minute error included in the output error obtained by the error signal generating unit 2. A multiplier 32 and a low-pass filter 33 are provided as means for detecting the frequency component of vibration, and an integrator 34 is provided as an integrating means for integrating the output of the detecting means to obtain the output control signal of the parameter control section.
Equipped with. The output of the integrator 34 is output to the neural network 11 after the small vibration from the oscillator 31 is superimposed by the adder 35.

The characteristic feature of this embodiment is that the output of the oscillator 31 is used as the output of the oscillator 3 of another parameter control unit 3.
When the harmonic, sum frequency, or difference frequency of the superposed frequency generated by 1 substantially matches and becomes the crosstalk frequency, the phase of the microvibration generated by itself is compared with the phase of the crosstalk frequency. This is because a phase adjuster 36 that shifts π / 2 or an odd multiple thereof is provided.

The error signal generator 2 has a plurality of inputs because the controlled object is the neural network 11, and is provided with a plurality of circuits including a subtractor 21 and a squaring circuit 22, and outputs of these circuits are provided. Adder 2 to add
3 is provided.

In this embodiment, the direct current component of the synchronous detection output in the parameter control unit 3 depends on the phase difference between the multiplied frequencies, that is, the different phase θ,
Multiplying two signals of the same frequency f having θ ′, cos (2πft + θ) × cos (2πft + θ ′) = (1/2) {cos (θ−θ ′) + cos (4πft + θ + θ ′) (1) I'm taking advantage of it. In this equation, the DC component (1/2) cos (θ−θ ′) on the right side becomes zero when the phase difference is | θ−θ ′ | = (2n + 1) π / 2. Therefore, the crosstalk between frequencies can be suppressed by adjusting the phase difference between the frequencies appearing as crosstalk to π / 2 or an odd multiple thereof.

2 to 4 each show a crosstalk suppressing method.

The crosstalk is (1) k-th frequency f
_{When k} is equal to the second harmonic 2f _i of i-th frequency f _i, (2) l-th frequency f _l is the i-th frequency f _i
And the j-th frequency f _j matches the sum frequency,
(3) It occurs when the m-th frequency f _m matches the i-th frequency f _i and the j-th frequency f _j and the difference frequency. In either case, by shifting the phase between frequencies causing crosstalk by π / 2 or an odd multiple thereof, crosstalk between superimposed frequencies can be suppressed at the output of the multiplier 32.

FIG. 5 shows an example of frequency arrangement, and FIGS. 6 and 7 show the phase determination method for each frequency.

Here, it is assumed that the lowest frequency is f _0, and frequencies up to frequency f _2n-1 are assigned to the oscillator 31 within the same frequency interval within 2 octaves. In this arrangement, the phase determination method for each frequency when n is an even number is shown in FIG. 6, and the phase determination method when n is an odd number is shown in FIG.
θ ₀ , θ ₁ , ..., θ _2n-1 are the superposed frequencies f, respectively.
The phases of ₀ , f ₁ , ..., F _2n-1 are represented.

When n is an even number, first, the frequencies f ₀ ,
Based on the phase of f ₁ , these second harmonics 2f ₀ , 2
f ₁ and frequencies f _n , f equal to these second harmonics
Phase difference between _{n + 2} | 2θ ₀ −θ _n |, | 2θ ₁ −θ _{n + 2}
Θ _n and θ _{n + 2} are adjusted so that | becomes an odd multiple of π / 2. Next, the phase of the sum frequency f ₀ + f ₁ of the frequencies f ₀ and f ₁ and the phase θ _{n + 1} of the frequency f _{n + 1} equal to the sum frequency
Θ _{n + 1} is adjusted such that the phase difference | θ ₀ + θ ₁ −θ _{n + 1} | with and becomes an odd multiple of π / 2. Furthermore, the frequency f ₀ ,
f and the phase of the n _{+ 2} of the difference frequency f _{n + 2} -f _0, the phase difference between the phase theta ₂ of frequency f ₂ is equal to the difference frequency | theta _{n + 2} - [theta]
_The phase θ ₂ is adjusted so that ₀ −θ ₂ | is an odd multiple of π / 2. Then, the phase θ _{n + 2} is used to determine the phase θ _{n + 4} , and the phases θ ₁ and θ ₂ are used to determine the phase θ _{n + 3} .

Thus, using the phase of the lowest frequency,
The phases are sequentially determined up to θ _2n−1 and θ _{n / 2-1 in the} order of the harmonic, the phase of the sum frequency, and the phase of the next lower frequency. From θ _{n / 2} to θ _n-1 , f _{n + k} (k> 0) and f
It is determined by using the difference frequency component of ₀ .

Similarly, when n is an odd number, the frequencies f ₀ and f
_With reference to the phases θ ₀ and θ ₁ of ₁ , the phases are sequentially determined from the lowest frequency phase to θ _2n-1 and θ _{(n-1) / 2} . θ
_{About n / 2} to θ _n-1, it is determined using the difference frequency component between f _{n + k} (k> 0) and f ₀ .

According to this embodiment, the frequency range of superposed small vibrations can be expanded to octave or more, and the number of controllable parameters can be increased. However, when the frequency range is limited, the number of parameters is limited. In the following embodiments, a configuration that can increase the number of parameters even when the frequency range is limited will be described.

FIG. 8 is a block diagram showing a non-linear system controller according to the second embodiment of the present invention. Here, similarly to the first embodiment, a case where a neural network is a control target will be described as an example.

In this embodiment, two parameter control units 4a and 4b use the same superposition frequency, and only one of them, that is, the parameter control unit 4b, has the phase adjuster 36.
Is different from the first embodiment. The parameter control unit 4a is equivalent to that shown in the conventional example, and includes an oscillator 31,
A multiplier 32, a low pass filter 33, an integrator 34 and an adder 35 are provided. On the other hand, the parameter control unit 4
b is equivalent to that shown in the first embodiment and further includes a phase adjuster 36. The phase adjuster 36 adjusts the phase between the same superimposed frequencies, and with respect to the phase of the minute vibration generated by the oscillator 31 of the parameter control unit 4a,
The phase of the minute vibration generated from the oscillator 31 in the own parameter control unit 4b is shifted by π / 2 or an odd multiple thereof.

FIG. 9 shows the phase difference between minute vibrations having the same frequency. This diagram is the same as that shown in each of FIGS. 2 to 4 except that the superposed frequencies themselves are the same. In the first embodiment, the phase adjustment is performed when the superimposed frequency in a certain parameter control unit 3 and the harmonic of the superimposed frequency in another parameter control unit 3 have the same frequency. On the other hand, in the second embodiment, the phase adjustment is performed when the superposed frequency itself is the same frequency, and the principle is the same as in the first embodiment. By making it possible to use the same frequency in this way, the number of parameters can be increased even when the frequency range is limited.

FIG. 10 is a block diagram showing a non-linear system controller according to the third embodiment of the present invention. This embodiment differs from the second embodiment in that two parameter control units 5a and 5b share the oscillator 31. That is, the parameter control unit 5a includes an oscillator 31, a multiplier 32, a low-pass filter 33, an integrator 34, and an adder 35, while the parameter control unit 5b includes a multiplier 32, a low-pass filter 33, an integrator 34, and an adder. The output of the oscillator 31 is supplied from the parameter control unit 5a to the parameter control unit 5b via the phase adjuster 36. At this time, the phase adjuster 36 uses the parameter control unit 5a.
The phase of the minute vibration generated by the oscillator 31 is shifted by π / 2 or an odd multiple thereof. Therefore, the two parameter control units 5a and 5b can superimpose a minute signal having the same frequency and a different phase on the control signal. This allows
Similar to the second embodiment, the number of parameters can be increased even when the frequency range is limited.

[0038]

As described above, the non-linear system control device of the present invention increases the number of minute vibrations that can be superimposed by giving a phase difference of π / 2 or an odd multiple thereof to the signals that cause crosstalk. , The number of controllable parameters can be increased. In particular, when the superposition frequency and the harmonic of the other superposition frequency, or either the sum frequency or the difference frequency become substantially the same frequency, by shifting the superposition frequency, it is possible to limit the frequency range of the microvibration to be superposed. It becomes possible to arrange it more than octave and it is possible to greatly increase the number of controllable parameters. Further, even when the frequency range is limited, the number of controllable parameters can be increased more than before by using the same frequency with the phase shifted.

[Brief description of drawings]

FIG. 1 is a block diagram showing a non-linear system control device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a method of suppressing crosstalk.

FIG. 3 is a diagram showing a method of suppressing crosstalk.

FIG. 4 is a diagram showing a method of suppressing crosstalk.

FIG. 5 is a diagram showing an example of frequency allocation.

FIG. 6 is a diagram showing a phase determination method for each frequency.

FIG. 7 is a diagram showing a phase determination method for each frequency.

FIG. 8 is a block diagram showing a non-linear system control device according to a second embodiment of the present invention.

FIG. 9 is a diagram showing a phase difference between minute vibrations having the same frequency.

FIG. 10 is a block diagram showing a non-linear system control device according to a third embodiment of the present invention.

FIG. 11 is a block configuration diagram showing a conventional non-linear control device.

FIG. 12 is a block configuration diagram showing details of an error signal generator.

FIG. 13 is a block configuration diagram showing details of a parameter control unit.

FIG. 14 is a diagram illustrating an operation of a conventional example.

[Explanation of symbols]

2, 20 Error signal generator 3, 4a, 4b, 5a, 5b, 30, 30a, 30b
Parameter control unit 10 Non-linear circuit 11 Neural network 21 Subtractor 22 Square circuit 23, 35 Adder 31 Oscillator 32 Multiplier 33 Low-pass filter 34 Integrator 36 Phase adjuster

Claims (2)

[Claims] 1. A plurality of parameter control units comprising: a plurality of parameter control units that respectively provide control signals to a control target whose input / output characteristics are nonlinear; and an error signal generation unit that obtains an output error of the control target. A vibration superimposing means for superimposing microvibrations of different frequencies on the output control signal, and means for detecting the frequency component of the microvibration included in the output error obtained by the error signal generating section, In a non-linear system control device including an integrating means for integrating the output of the detecting means to obtain an output control signal of the parameter control section, the vibration superimposing means is characterized in that the vibration superimposing means of the other parameter controlling section with respect to the superimposing frequency. When any of the harmonics, sum frequency or difference frequency of the superposed frequency generated by the means substantially coincides with each other and becomes the crosstalk frequency, the crosstalk frequency Π is the phase of the minute vibration generated by itself with respect to the phase of the Stokes frequency.
A non-linear system control device including phase adjustment means for shifting by 1/2 or an odd multiple thereof. 2. A plurality of parameter control units, each of which includes a plurality of parameter control units that give a control signal to a control target whose input / output characteristics are non-linear and an error signal generation unit that obtains an output error of the control target. Are respectively a vibration superimposing means for superimposing a microvibration on the output control signal, a means for detecting the frequency component of the microvibration included in the output error obtained by the error signal generating section, and a means for detecting this. In a non-linear system control device including an integrating means for integrating an output into an output control signal of the parameter control unit, the vibration superimposing means is a small amount generated by another vibration superimposing means using substantially the same frequency. A non-linear system control device comprising phase adjusting means for shifting the phase of minute vibration generated by itself with respect to the phase of vibration by π / 2 or an odd multiple thereof.