CN108254147B - Frequency-division amplitude modulation system for feedback signal of vibrating table - Google Patents
Frequency-division amplitude modulation system for feedback signal of vibrating table Download PDFInfo
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Abstract
The invention discloses a vibration table feedback signal frequency division amplitude modulation system, which is an adjustable amplifier formed by connecting an in-phase proportional amplifying circuit and a voltage dividing potentiometer in series, wherein an input signal of the adjustable amplifier is a current working frequency signal, frequency division and amplitude compensation information of a vibration table working range are preset in the adjustable amplifier, the adjustable amplifier compares the current working frequency signal to the frequency division information to obtain the amplification factor of the frequency division, the amplification factor is converted into amplitude modulation control pulses, and each amplitude modulation control pulse correspondingly adjusts the resistance value of the potentiometer. The invention not only can reduce the difficulty of constructing the feedback controller and adjusting parameters, but also can adaptively amplitude-modulate the feedback signal when the vibrating table outputs vibration signals in different frequency bands.
Description
Technical Field
The invention relates to a feedback signal adjusting system in a low-frequency vibrating table system.
Background
The electromagnetic vibration table has the advantages of wide frequency range, good controllability, high output waveform precision and the like, and is widely applied to important fields of product simulation vibration environment test, vibration measurement sensor calibration and the like. In order to improve the accuracy of the output waveform of the vibrating table at low frequencies (reduce the distortion), it is generally necessary to construct a feedback control system. However, the precondition for realizing feedback control is that an output vibration signal of the vibration table is detected by a vibration sensor (acceleration, speed or displacement sensor) or other motion quantity detection devices, then the output vibration signal is used as a feedback signal, and is differenced with an input signal of a system, the deviation signal excites the vibration table to vibrate after passing through a controller and a power amplifier, and finally, the construction of a closed-loop control system is completed, so that negative feedback control on the distortion degree of the output waveform of the vibration table is realized. In an ideal case where there is no phase shift between the feedback signal and the input signal, the negative feedback control can effectively suppress nonlinear distortion of the vibrating table. Further, the suppression effect of the method on nonlinear distortion is related to the feedback depth (amplification factor on the feedback channel).
Because of the limitation of the amplitude of the output motion quantity of the vibrating table and the phase shift of the system, the motion signal obtained by directly detecting the vibration sensor or other motion quantity detecting devices is used as a feedback signal, the suppression effect of the negative feedback control on nonlinear distortion can be reduced, and even positive feedback can occur. In order to make the negative feedback control system have better output waveform control function on the vibrating table, a PID controller with a complex structure is required to be designed under normal conditions, and correction of deviation signals in the negative feedback system is completed through repeated adjustment of parameters of the PID controller, so that the distortion degree of output waveforms is reduced. However, the introduction of the PID controller inevitably increases the complexity of the vibrating table negative feedback control system and the difficulty of adjusting the system parameters.
Disclosure of Invention
The invention aims to provide a system capable of reducing the difficulty of building a feedback controller and adjusting parameters and adaptively amplitude-modulating the feedback signal when a vibrating table outputs vibration signals in different frequency ranges.
The frequency segmentation and amplitude compensation information of the working range of the vibrating table are preset in the adjustable amplifier, the adjustable amplifier compares the current working frequency signal to the frequency segmentation information to obtain the amplification factor of the frequency segmentation and converts the amplification factor into amplitude modulation control pulses, and each amplitude modulation control pulse correspondingly adjusts the resistance value of the potentiometer.
Further, the current working frequency signal is output by a frequency detection unit, and the frequency detection unit comprises a comparator, a counter and a frequency controller; the comparator, the counter and the frequency controller are connected in sequence; the system input signal and the reference signal are input into the comparator together, the comparator outputs a square wave signal formed by the system input signal and the reference signal, the square wave signal and the digital clock pulse signal are input into the counter together, the counter outputs the number of periods of the system input signal and the number of periods of the digital clock pulse signal, the frequency controller outputs the frequency value of the system input signal, the frequency controller outputs an amplitude modulation control pulse, the frequency of the square wave signal corresponds to the frequency of the vibrating system input signal and is the same as the working frequency and the feedback signal frequency of the system.
Further, the output end of the adjustable amplifier is connected with the input end of the adjustable phase shifter, the adjustable phase shifter is formed by connecting two stages of all-pass filters in series, the frequency detection unit outputs phase-shifting control pulses according to the frequency value ff of the system input signal, and the phase-shifting control pulses adjust the resistance of the adjustable digital potentiometer of the first stage of all-pass filter and the resistance of the adjustable digital potentiometer of the second stage of all-pass filter.
The amplification factor of different frequency bands of the adjustable amplifier is determined as follows:
1) And inputting excitation signals with different frequencies into the vibrating table in the working frequency range, and constructing a negative feedback control system. And under different frequencies, different gains are applied to the amplitude of the feedback signal, the precision characteristic of the output signal of the vibrating table under the conditions of corresponding frequencies and corresponding gains of the feedback signal is detected, and the gains required by the feedback signal under different frequencies can be obtained according to the gains of the feedback signal meeting the precision requirement of the vibrating table. The operating frequency range of the vibrating table is divided into (k' -1) segments, denoted:
f m ≤f<f m +1 ,m＝1 ,2 ,3 ,...k′-1；
2) For each frequency segment in turn, taking the average value of the frequency gains in the current frequency segment as the gain p of the current frequency segment m ；
3) The gain for each band is expressed as:
，
wherein R is 6 Is the resistance value of a feedback resistor in the in-phase proportional amplifying circuit, R 7 Is the total resistance value of the voltage dividing potentiometer, R 7w Is the partial pressure resistance value of the partial pressure potentiometer;
4) Determining the resistance R of a fixed resistor of an in-phase proportional amplifying circuit 5 Judging whether the current frequency segment needs to amplify or attenuate the signal, and taking R when the signal needs to be amplified 7w ＝R 7 Obtaining R 6 The method comprises the steps of carrying out a first treatment on the surface of the By R 6 Value sum R 7w As a ginsengCalculating the number of amplitude modulation control pulses to be input into a feedback resistor in the in-phase proportional amplifying circuit and the number of amplitude modulation control pulses of the voltage dividing potentiometer, so as to control the adjustable amplifier to adjust the amplitude of the feedback signal of the corresponding frequency band;
taking R when signal attenuation is required 6 =0, find the required R 7w The method comprises the steps of carrying out a first treatment on the surface of the By R 6 Value sum R 7w The number of amplitude modulation control pulses which are required to be input into a feedback resistor in the in-phase proportional amplifying circuit and the number of amplitude modulation control pulses of the voltage dividing potentiometer are obtained by reference calculation, so that the adjustable amplifier is controlled to realize the adjustment of the amplitude of the feedback signal of the corresponding frequency band. Further, the phase shift value of the adjustable phase shifter in different frequency bands is determined as follows:
s1: and in the working frequency range, exciting signals with different frequencies are input to the vibrating table, and a negative feedback control system is constructed. And under different frequencies, different phases of the feedback signal are adjusted, the precision characteristics of the output signal of the vibrating table under the conditions of corresponding frequencies and phases of the feedback signal are detected, and the phase shift value required by the feedback signal under different frequencies can be obtained according to the phases of the feedback signal meeting the precision requirement of the vibrating table. Dividing the operating frequency range of the oscillating table into k-1 segments, denoted f n ≤f<f n +1, n=1, 2, 3,..k-1, the criterion for the segments is that the phase shift value of the feedback signal within the segment is the same; the phase shift values herein being identical means that the difference between the phase shift values for each frequency within the frequency segment is within the allowable deviation range;
s2: for each frequency segment in turn, taking the average value of the phase shift values of the frequencies in the frequency segment as the phase shift value of the frequency segmentTo->As f n Phase shift values of the frequency segmented adjustable phase shifter;
s3: for f n The phase shift value of the frequency segment is expressed as:
；
wherein: r is R 2 R is the resistance value of a digital potentiometer in the first-stage all-pass filter 3 The resistance value of the digital potentiometer in the second-stage all-pass filter;
s4: let R 2 ＝R 3 Combining the steps S2 and S3 to obtain R corresponding to each frequency segment 2 、R 3 Value, for each frequency segment, R 2 、R 3 And calculating the number of phase-shifting control pulses required to be input into the adjustable digital potentiometer in the first-stage all-pass filter and the adjustable digital potentiometer in the second-stage all-pass filter by taking the value as a reference, and controlling the phase-shifting value of the corresponding frequency segment generated by the adjustable phase shifter.
The invention has the advantages that:
1. the working frequency of the vibrating table is segmented, each frequency segment is respectively carried out, each frequency is not required to be independently phase-shifted, the difficulty of building and parameter adjustment of a feedback controller is reduced, and the accuracy of a negative feedback signal is high.
2. The working frequency of the vibrating table is segmented, amplitude modulation is respectively carried out on each frequency segment, each frequency does not need to be independently subjected to amplitude modulation, the speed detection device is simplified, and the difficulty of building and parameter adjustment of the feedback controller is reduced.
Drawings
Fig. 1 is a schematic structural view of the present invention.
Fig. 2 is a schematic diagram of the adjustable amplifier of the present invention.
Fig. 3 is a schematic diagram of an adjustable amplifier connected to an adjustable phase shifter.
Detailed Description
Example 1
Referring to fig. 1, the vibration table feedback signal frequency-division amplitude modulation system comprises a frequency detection unit and an adjustable amplifier. The signal input end of the frequency detection unit is connected with the input signal of the vibrating table system, and the output end of the frequency detection unit is respectively connected with the pulse input ends of the adjustable phase shifter and the adjustable amplifier. Signal input end and motion quantity detection of the adjustable phase shifterThe vibration table detected by the detecting device outputs a motion signal u i The output end of the adjustable amplifier is connected with the signal input end of the adjustable amplifier, and the output end of the adjustable amplifier is a vibration table system feedback signal u after amplitude adjustment fb 。
The input signal of the vibrating table system is input into the frequency detection unit, and the frequency detection unit outputs corresponding number of phase-shifting control pulses and amplitude-modulation control pulses to the adjustable phase shifter and the adjustable amplifier according to the frequency value of the signal.
Output motion signal u of vibrating table detected by motion amount detecting device in vibrating table negative feedback control system i And the feedback signal is input into the adjustable phase shifter, the output phase of the adjustable phase shifter is compensated, and the feedback signal is input into the adjustable amplifier again.
Referring to fig. 1, the frequency detection unit includes a comparator, a counter and a frequency controller, wherein the input signal of the vibrating table system and the reference input signal are input into two input ends of the comparator together, the comparator outputs a square wave signal with the same frequency as the input signal of the vibrating table system according to the existing conventional comparator structural design. The square wave signal and the digital clock pulse signal are input into a counter together, the counter can respectively trigger and count rising edges of the square wave signal and the digital clock pulse signal, and the number of rising edges is recorded in time t to obtain the number N of the cycles of the square wave signal f Number of cycles N of digital clock signal s Output the number of cycles N of square wave signal f Number of cycles N of digital clock signal s The frequency controller is given to the frequency controller according to the cycle number N of the square wave signal f And number of digital clock pulse periods N s Calculating to obtain the frequency value f of the square wave signal f I.e. the frequency value of the system input signal is:
wherein f s Is a fixed value, is the frequency of the digital clock pulse signal, and the counter and the frequency controller pass through the baseThe digital signal processing unit is realized by an FPGA or a DSP.
The system input signal and the known reference input signal are input to the comparator, the comparator outputs a high level when the amplitude of the system input signal is higher than the amplitude of the reference input signal, whereas the comparator outputs a low level, whereby the comparator outputs a square wave signal having the same frequency as the system input signal. At this time, the frequency of the square wave signal is unknown, so that the square wave signal and the digital clock pulse signal are simultaneously input into the counter, the counter counts the cycle number of the square wave signal, and the frequency of the digital clock is known, and in the same time, the frequency of the square wave can be calculated according to the ratio of the cycle number of the square wave signal to the cycle number of the digital clock signal, and the frequency of the input signal of the system is known from the frequency of the square wave, so that the frequency corresponds to the corresponding frequency segment.
The frequency detection unit outputs amplitude modulation control pulses with corresponding numbers according to the detected frequency value of the system input signal to control the third digital potentiometer and the fourth digital potentiometer to output corresponding resistance values, so that the amplitude of the input adjustable amplifier signal is adjusted.
As shown in fig. 2, the adjustable amplifier is formed by connecting an in-phase proportional amplifying circuit and a voltage dividing potentiometer in series, and the amplification factor determining steps of different frequency bands of the adjustable amplifier are as follows:
1) And inputting excitation signals with different frequencies into the vibrating table in the working frequency range, and constructing a negative feedback control system. And under different frequencies, different gains are applied to the amplitude of the feedback signal, the precision characteristic of the output signal of the vibrating table under the conditions of corresponding frequencies and corresponding gains of the feedback signal is detected, and the gains required by the feedback signal under different frequencies can be obtained according to the gains of the feedback signal meeting the precision requirement of the vibrating table. The operating frequency range of the vibrating table is divided into (k' -1) segments, denoted:
f m ≤f<f m +1 ,m＝1 ,2 ,3 ,...k′-1；
2) For each frequency segment in turn, taking the average value of the gains of the frequencies in the current frequency segment as the gain p of the current frequency segment m ；
3) The gain for each band is expressed as:
wherein R is 6 Is the resistance value of a feedback resistor in the in-phase proportional amplifying circuit, R 7 Is the total resistance value of the voltage dividing potentiometer, R 7w Is the partial pressure resistance value of the partial pressure potentiometer;
4) Determining the resistance R of a fixed resistor of an in-phase proportional amplifying circuit 5 Judging whether the current frequency segment needs to amplify or attenuate the signal, and taking R when the signal needs to be amplified 7w ＝R 7 Obtaining R 6 The method comprises the steps of carrying out a first treatment on the surface of the By R 6 Value sum R 7w The number of amplitude modulation control pulses which are required to be input into a feedback resistor in the in-phase proportional amplifying circuit and the number of amplitude modulation control pulses of the voltage dividing potentiometer are obtained by reference and calculation, so that the adjustable amplifier is controlled to realize the adjustment of the amplitude of a feedback signal of a corresponding frequency band;
taking R when signal attenuation is required 6 =0, find the required R 7w The method comprises the steps of carrying out a first treatment on the surface of the By R 6 Value sum R 7w The number of amplitude modulation control pulses which are required to be input into a feedback resistor in the in-phase proportional amplifying circuit and the number of amplitude modulation control pulses of the voltage dividing potentiometer are obtained by reference calculation, so that the adjustable amplifier is controlled to realize the adjustment of the amplitude of the feedback signal of the corresponding frequency band.
The working frequency of the vibrating table is segmented, amplitude modulation is respectively carried out on each frequency segment, each frequency does not need to be independently subjected to amplitude modulation, and the difficulty of building and parameter adjustment of the feedback controller is reduced.
Example 2
The difference between this embodiment and embodiment 1 is that the output end of the adjustable amplifier is connected to the input end of the adjustable phase shifter, and the structure and phase shifting method of the adjustable phase shifter. The rest of the structure and method are the same as in example 1.
Referring to fig. 3, the adjustable phase shifter is formed by connecting two stages of all-pass filter circuits in series, wherein a filter resistor (the filter resistor refers to RC electricity with a filtering function) in the first stage of all-pass filter circuitResistance in the path) is a first digital potentiometer, and the resistance value is expressed as R 2 The method comprises the steps of carrying out a first treatment on the surface of the The filter resistor in the second-stage all-pass filter circuit is a second digital potentiometer, and the resistance value is expressed as R 3 . The first digital potentiometer and the second digital potentiometer are adjustable digital potentiometers, the frequency detection unit outputs corresponding number of phase shift control pulses according to the detected frequency value of the system input signal to control the first digital potentiometer and the second digital potentiometer to output different resistance values, and 0-360-degree phase shift can be achieved on the signal input into the adjustable phase shifter. The phase shift value of the adjustable phase shifter in different frequency ranges is determined as follows:
(1) And inputting excitation signals with different frequencies into the vibrating table in the working frequency range, and constructing a negative feedback control system. And under different frequencies, different phases of the feedback signal are adjusted, the precision characteristics of the output signal of the vibrating table under the conditions of corresponding frequencies and phases of the feedback signal are detected, and the phase shift value required by the feedback signal under different frequencies can be obtained according to the phases of the feedback signal meeting the precision requirement of the vibrating table. According to the size of the operating frequency range of the vibrating table and the phase shift values of the feedback signals under different frequencies, the operating frequency range of the vibrating table can be divided into a plurality of sections, each section is ensured to have feedback signal phase shift values close to each other, and the frequency range is divided into (k-1) sections, which can be expressed as:
f n ≤f<f n +1 ,n＝1 ,2 ,3 ,...k-1；
(2) In each frequency band, taking the average value of the phase shift values of the frequencies as the phase shift value of the adjustable phase shifter of the frequency band；
(3) Taking the average value of the frequencies of each frequency band in (1) as a reference, according to the circuit characteristics of the adjustable phase shifter, the phase shift value corresponding to each frequency band is expressed as:
wherein R is 2 Is the first stageResistance value R of adjustable digital potentiometer of pass filter 3 The resistance value of the adjustable digital potentiometer of the second-stage all-pass filter;
(4) Let R 2 ＝R 3 Combining the steps (2) and (3) to obtain R corresponding to each frequency band 2 、R 3 Value of R as 2 、R 3 The value can be used as a reference to calculate the number of phase-shifting control pulses which need to be input into the first digital potentiometer and the second digital potentiometer, so as to control the adjustable phase shifter to generate phase-shifting values of corresponding frequency bands.
The embodiment can carry out amplitude phase self-adaptive adjustment on the feedback signal of the vibrating table system by frequency division, so that the feedback signal has amplitude and phase meeting the requirements of a negative feedback control system.
The present invention is further illustrated by the following examples, but the present invention is not limited to these examples. It will be appreciated by those skilled in the art that the invention encompasses all alternatives, modifications and equivalents as may be included within the scope of the claims.
Claims (3)
1. The frequency segmentation and amplitude compensation information of the working range of the vibrating table are preset in the adjustable amplifier, the adjustable amplifier compares the current working frequency signal to the frequency segmentation information to obtain the amplification factor of the frequency segmentation and converts the amplification factor into amplitude modulation control pulses, and each amplitude modulation control pulse correspondingly adjusts the resistance value of the potentiometer;
the amplification factor of different frequency bands of the adjustable amplifier is determined as follows:
1) Inputting excitation signals with different frequencies to the vibrating table in the working frequency range, and constructing a negative feedback control system; under different frequencies, different gains are applied to the amplitude of the feedback signal, and the precision characteristics of the output signal of the vibrating table under the corresponding frequency and corresponding gain conditions of the feedback signal are detected, thereby meeting the requirements of vibrationThe gain of the feedback signal required by the accuracy of the movable platform can obtain the gain required by the feedback signal under different frequencies; the operating frequency range of the vibrating table is divided into (k' -1) segments, denoted: f (f) m ≤f<f m +1 ,m＝1 ,2 ,3 ,...k′-1；
2) For each frequency segment in turn, taking the average value of the frequency gains in the current frequency segment as the gain p of the current frequency segment m ；
3) The gain for each band is expressed as:wherein R is 6 Is the resistance value of a feedback resistor in the in-phase proportional amplifying circuit, R 7 Is the total resistance value of the voltage dividing potentiometer, R 7w Is the partial pressure resistance value of the partial pressure potentiometer;
4) Determining the resistance R of a fixed resistor of an in-phase proportional amplifying circuit 5 Judging whether the current frequency segment needs to amplify or attenuate the signal, and taking R when the signal needs to be amplified 7w ＝R 7 Obtaining R 6 The method comprises the steps of carrying out a first treatment on the surface of the By R 6 Value sum R 7w The number of amplitude modulation control pulses which are required to be input into a feedback resistor in the in-phase proportional amplifying circuit and the number of amplitude modulation control pulses of the voltage dividing potentiometer are obtained by reference and calculation, so that the adjustable amplifier is controlled to realize the adjustment of the amplitude of a feedback signal of a corresponding frequency band;
taking R when signal attenuation is required 6 =0, find the required R 7w The method comprises the steps of carrying out a first treatment on the surface of the By R 6 Value sum R 7w The number of amplitude modulation control pulses which are required to be input into a feedback resistor in the in-phase proportional amplifying circuit and the number of amplitude modulation control pulses of the voltage dividing potentiometer are obtained by reference calculation, so that the adjustable amplifier is controlled to realize the adjustment of the amplitude of the feedback signal of the corresponding frequency band.
2. The oscillating table feedback signal frequency-division amplitude modulation system of claim 1, wherein: the current working frequency signal is output by a frequency detection unit, and the frequency detection unit comprises a comparator, a counter and a frequency controller; the comparator, the counter and the frequency controller are connected in sequence; the system input signal and the reference signal are input into the comparator together, the comparator outputs a square wave signal formed by the system input signal and the reference signal, the square wave signal and the digital clock pulse signal are input into the counter together, the counter outputs the number of periods of the system input signal and the number of periods of the digital clock pulse signal, the frequency controller outputs the frequency value of the system input signal, the frequency controller outputs an amplitude modulation control pulse, the frequency of the square wave signal corresponds to the frequency of the vibrating system input signal and is the same as the working frequency and the feedback signal frequency of the system.
3. The oscillating table feedback signal frequency-division amplitude modulation system of claim 2, wherein: the output end of the adjustable amplifier is connected with the input end of the adjustable phase shifter, the adjustable phase shifter is formed by connecting two stages of all-pass filters in series, and the frequency detection unit is used for detecting the frequency value f of the input signal of the system f And outputting phase-shifting control pulses, wherein the phase-shifting control pulses adjust the resistance of the adjustable digital potentiometer of the first-stage all-pass filter and the resistance of the adjustable digital potentiometer of the second-stage all-pass filter.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5594177A (en) * | 1995-05-17 | 1997-01-14 | Hanse; John K. | Shaker table |
| JP2000088817A (en) * | 1998-09-17 | 2000-03-31 | Mitsubishi Electric Corp | Hammering determining device |
| CN102288282A (en) * | 2011-05-04 | 2011-12-21 | 浙江大学 | Vibration table system with feedback control device based on linear optical grating ruler |
| CN102322391A (en) * | 2011-05-27 | 2012-01-18 | 新疆风能有限责任公司 | Protection method for carrying out predictive analysis on vibration condition of wind turbine blades |
| CN102319664A (en) * | 2011-05-04 | 2012-01-18 | 浙江大学 | Electromagnetic vibration table system with adjustable electric viscoelastic support device |
| CN103245366A (en) * | 2013-04-25 | 2013-08-14 | 南京航空航天大学 | Vibration signal differentiating circuit |
-
2018
- 2018-01-22 CN CN201810060509.3A patent/CN108254147B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5594177A (en) * | 1995-05-17 | 1997-01-14 | Hanse; John K. | Shaker table |
| JP2000088817A (en) * | 1998-09-17 | 2000-03-31 | Mitsubishi Electric Corp | Hammering determining device |
| CN102288282A (en) * | 2011-05-04 | 2011-12-21 | 浙江大学 | Vibration table system with feedback control device based on linear optical grating ruler |
| CN102319664A (en) * | 2011-05-04 | 2012-01-18 | 浙江大学 | Electromagnetic vibration table system with adjustable electric viscoelastic support device |
| CN102322391A (en) * | 2011-05-27 | 2012-01-18 | 新疆风能有限责任公司 | Protection method for carrying out predictive analysis on vibration condition of wind turbine blades |
| CN103245366A (en) * | 2013-04-25 | 2013-08-14 | 南京航空航天大学 | Vibration signal differentiating circuit |
Non-Patent Citations (1)
| Title |
|---|
| Self-Sensing Waveform Control for a Low-Frequency Electromagnetic Vibrator;Zhang Xufei;IEEE-ASME TRANSACTIONS ON MECHATRONICS;第785-793页 * |
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