CN104950936A - Resonance frequency tracking and vibration load amplitude combined control system based on stable amplitude - Google Patents

Abstract

The invention discloses a resonance frequency tracking and vibration load amplitude combined control system based on stable amplitude. The resonance frequency tracking and vibration load amplitude combined control system adopts a two-layer fuzzy controller structure, wherein a supervision management controller is arranged on the upper layer and performs planning of a frequency and amplitude control sequence as well as calculation and output of control values on a frequency tracking controller and a resonance zone amplitude controller which are located on the lower layer by monitoring the crack propagation length, the load amplitude as well as the sampling control time of the resonance frequency; the frequency tracking controller and the resonance zone amplitude controller are arranged on the lower layer. The resonance frequency tracking and vibration load amplitude combined control system based on stable amplitude has good dynamic property and performs resonance frequency tracking and vibration load amplitude control simultaneously in a fatigue crack propagation control process.

Description

Resonance frequency based on fixed ampllitude is followed the tracks of and oscillating load amplitude combined control system

Technical field

The present invention relates to frequency-tracking and the amplitude controlling field of vibrational system, particularly a kind of resonance frequency based on fixed ampllitude is followed the tracks of and oscillating load amplitude combined control system.

Background technology

The serviceability of electromagnetic resonance HF fatigue testing machine directly affects the accuracy of test findings, should in crack propagation process the natural frequency of strict tracker the stability of Control experiment load.Resonant mode fatigue crack propagation test system resonance frequencies tracking technique in the past and the fuzzy control technology of resonance region test load amplitude, although system works can be made in resonance region and the stability of amplitude reserving, but because frequency-tracking and amplitude controlling independently carry out, first trace into system resonance point, then carrying out amplitude controlling in resonance region makes amplitude reach setting value, amplitude overshoot can be caused like this in control procedure to vibrate, system can not be made to have good dynamic property, if make the stability of system also amplitude reserving in Crack Extension frequency adjustment process, must amplitude controlling and frequency-tracking carry out simultaneously.

Summary of the invention

Cannot carry out to overcome in existing crack Propagation control procedure the deficiency that resonance frequency is followed the tracks of and oscillating load amplitude controlling, dynamic property are poor simultaneously, the invention provides in a kind of crack Propagation control procedure and carrying out resonance frequency is followed the tracks of and oscillating load amplitude controlling, dynamic property the are good tracking of the resonance frequency based on fixed ampllitude and oscillating load amplitude combined control system simultaneously.

The technical solution adopted for the present invention to solve the technical problems is:

A kind of resonance frequency based on fixed ampllitude is followed the tracks of and oscillating load amplitude combined control system, described combined control system adopts double-deck fuzzy control system device structure, upper strata is supervision and management controller, by On Crack Propagation length, the monitoring in the controlling of sampling moment of load amplitude and resonance frequency, carry out the planning of frequency and amplitude controlling sequential and the calculating of controlling value and output to underlying frequency tracking control unit and resonance region amplitude controller, lower floor is frequency tracing control device and resonance region amplitude controller.

Further, described upper strata supervision and management controller be input as crack extending length and sampling instant, export have 3 classes: (1) according to sampling instant, control load fuzzy controller activationary time, determine its controlling value exported and control the moment; Controlled frequency fuzzy controller activationary time, determine its controlling value exported and control the moment, (2) according to the feature of gathered crack extending length and Crack Extension different phase, the domain of load fuzzy controller and frequency ambiguity controller is adjusted by adjustment quantized factor and proportional factor, principle is that Crack Extension initial stage Crack Extension is slower, amplitude variations is less, adopts little domain, less tracing step and less amplitude controlling amount; Crack Extension Crack Extension in mid-term is very fast, and amplitude variations is comparatively large, domain in employing, larger tracing step and larger amplitude controller; Crack Extension later stage Crack Extension is fast, and amplitude variations is large, adopts large domain, large tracing step and large amplitude controlling amount; (3) according to gathered crack extending length, the natural frequency value f of crack Propagation to system during this numerical value is calculated _theory, and by this value and now system operating frequency value f _ksubtract each other after taking absolute value and fuzzy controller input bf, bf must be multiplied by quantizing factor K ₁after be transformed into fuzzy domain, be input to fuzzy self-adaption resonance frequency tracking control unit.

Further again, the process jointly controlled repeats two stages: from k-1 moment to the k moment with from the k moment to the control procedure in k+1 moment, (1) from the k-1 moment to the k moment: only carried out frequency-tracking, and do not carry out amplitude controlling by changing exciting voltage, the change of amplitude-frequency response is caused by frequency-tracking, the input quantity eaf of calculated rate tracking control unit and bf, eaf are the difference of amplitude-frequency response after frequency-tracking and the ratio of corresponding frequency-tracking step-length another inputs bf=|f _theory-f _k| the absolute value of moment frequency values and theoretical natural frequency deviation for this reason, calculates tracing step Δ f required for next step by frequency tracing control device _k, calculate down 2 moment rate-adaptive pacemaker f _k+2=f _k+ Δ f _k, export subsequent time frequency f _k+1=f _krate-adaptive pacemaker remains unchanged, the amplitude output valve adopting the k-1 moment to calculate carries out amplitude controlling, (2) from the k moment to the k+1 moment: be carry out amplitude controlling by changing exciting voltage, frequency remains unchanged, the change of amplitude-frequency response caused by amplitude controlling, the deviation e=r-A of the input quantity e of calculated amplitude controller and ec, e moment amplitude-frequency response and setting value for this reason _k, ec deviation variation rate next step control voltage variation delta U is calculated by amplitude mode fuzzy controllers _k, calculate down 2 moment voltages and export U _k+2=U _k+ Δ U _k, the subsequent time rate-adaptive pacemaker amount that output previous moment calculates carries out frequency-tracking, and the exciting voltage of subsequent time exports the U that remains unchanged _k+1=U _k.

Further, the process from the k-1 moment to the k moment is repeated from the k+1 moment to the k+2 moment, repeat the process from the k moment to the k+1 moment from the k+2 moment to the k+3 moment, be recycled to frequency and amplitude controlling completes always, if after frequency adjusts to the right place, amplitude does not still arrive setting value, then carry out amplitude controlling continuously, as amplitude is adjusted to the right place and frequency does not adjust to resonance point, then frequency-tracking is followed the tracks of with minimum step 0.1Hz, amplitude controlling rule is constant, until find resonance point.

Technical conceive of the present invention is: in process of the test, amplitude and frequency intercouple, and owing to adjusting frequency while amplitude controlling, the change of amplitude caused by the change of amplitude caused by frequency change and electromagnetic exciter Voltage Cortrol can be superimposed.Therefore an input---frequency influence factor fa is increased on conventional vibration amplitude fuzzy controller basis, frequency influence factor fa is the output of frequency tracing control device, determine its impact on amplitude controlling according to frequency-tracking state, revise the fuzzy rule of resonance region amplitude controller accordingly.The output of amplitude controller is the variable quantity of electromagnetic exciter voltage, its state activation, and controlled quentity controlled variable calculates, and output time is provided by upper strata supervision and management controller.

The control of amplitude can impact frequency tracing control equally, therefore the resonance frequency tracker in jointly controlling has two major features: (1) is not calculating and the output of per moment all carrying out controlled quentity controlled variable, its state activation, controlled quentity controlled variable calculates, and output time is provided by upper strata supervision and management controller.(2) amplitude and frequency united controller will follow the tracks of resonance frequency on the basis as far as possible ensureing amplitude stability, reduce tracing step, the amplitude oscillatory caused because frequency-tracking step-length is comparatively large to reduce under same tracking mode.

Beneficial effect of the present invention is mainly manifested in: adopt based on fixed ampllitude resonance frequency follow the tracks of and oscillating load amplitude jointly control strategy, when crack Propagation, resonance frequency is followed the tracks of and amplitude controlling carries out simultaneously, achieve the stability of system amplitude reserving in Crack Extension frequency adjustment process, it is made to reach better control performance, the fuzzy control technology avoiding the system resonance frequencies tracking technique of resonant mode fatigue crack propagation test in the past and resonance region test load amplitude first traces into system resonance point, and then the amplitude overshoot vibration carried out amplitude controlling in resonance region and cause, system is made to have good dynamic property.

Accompanying drawing explanation

Fig. 1 follows the tracks of based on the resonance frequency of fixed ampllitude and oscillating load amplitude jointly controls tactful structure principle chart.

Fig. 2 be based on fixed ampllitude resonance frequency follow the tracks of and oscillating load amplitude jointly control amplitude derivative-frequency characteristic curve diagram in strategy.

Fig. 3 follows the tracks of based on the resonance frequency of fixed ampllitude and oscillating load amplitude jointly controls the membership function schematic diagram of fuzzy variable EAF in strategy.

Fig. 4 follows the tracks of based on the resonance frequency of fixed ampllitude and oscillating load amplitude jointly controls the membership function schematic diagram of fuzzy variable BF in strategy.

Fig. 5 follows the tracks of based on the resonance frequency of fixed ampllitude and oscillating load amplitude jointly controls the membership function schematic diagram of fuzzy variable Δ F in strategy.

Fig. 6 be based on fixed ampllitude resonance frequency follow the tracks of and oscillating load amplitude jointly control amplitude in strategy-frequency characteristic schematic diagram.

Fig. 7 follows the tracks of based on the resonance frequency of fixed ampllitude and oscillating load amplitude jointly controls the membership function schematic diagram of fuzzy variable E in strategy.

Fig. 8 follows the tracks of based on the resonance frequency of fixed ampllitude and oscillating load amplitude jointly controls the membership function schematic diagram of fuzzy variable EC in strategy.

Fig. 9 follows the tracks of based on the resonance frequency of fixed ampllitude and oscillating load amplitude jointly controls the membership function schematic diagram of fuzzy variable Δ U in strategy.

Embodiment

Below in conjunction with accompanying drawing, the invention will be further described.

With reference to Fig. 1 ~ Fig. 9, a kind of resonance frequency based on fixed ampllitude is followed the tracks of and oscillating load amplitude combined control system, and described combined control system adopts double-deck fuzzy control system device structure, as shown in Figure 1.Upper strata is supervision and management controller, by On Crack Propagation length, the monitoring in the controlling of sampling moment of load amplitude and resonance frequency, the planning of frequency and amplitude controlling sequential and the calculating of controlling value and output are carried out to underlying frequency tracking control unit and resonance region amplitude controller, timely output corresponding information is to lower floor's controller, and lower floor is made up of frequency tracing control device and resonance region amplitude controller.

In described frequency tracing control device,

1.1) determination of input quantity and output quantity

Adopt the ratio eaf of amplitude variations amount Δ A and corresponding frequency-tracking step delta f as input quantity, this value is equivalent to the derivative of Fig. 2 amplitude frequency curve.And regulation: it is just that amplitude increases Δ A, and it is negative for reducing Δ A, and it is just that same frequency increases Δ f, and it is negative for reducing Δ f, then have:

$eaf=\frac{\mathrm{\Δ}A}{\mathrm{\Δ}f}=\frac{A_k-A_{k-1}}{f_k-f_{k-1}}---\left(1\right)$

In formula, A _kfor sampling instant test sine wave oscillations load amplitude, A _k-1for previous moment test sine wave oscillations load amplitude, f _kfor sampling instant test sine wave oscillations load frequency, f _k-1for previous moment test sine wave oscillations load frequency.Know by analysis, each state in ratio eaf and frequency-tracking process is corresponding, with reference to Fig. 2, search from B point to C point, Δ A is just, Δ f is just, eaf is just, represent that Searching point is between BD, otherwise search from C point to B point, Δ A is negative, Δ f is negative, eaf is just, represent that Searching point is also between BD, if namely eaf is just, then current Searching point is between BD, next step answers straight line, no matter Δ A is for bearing or being just, identical step-size in search can be adopted, step-size in search adopts same fuzzy rule to determine, the starting point of next step search can be different, Δ A and Δ f is timing, get now state point B point and start Searching point for next step, Δ A and Δ f is for time negative, and getting previous state point B point starts Searching point for next step, that is:

f _k+1＝f _k-1+Δf _kΔf＜0,ΔA＜0

f _k+1＝f _k+Δf _kΔf＞0,ΔA＞0 (2)

So just searching for face (extreme point left side BCD section) eaf is just, antihunting face (on the right of extreme point DEF section) eaf is negative, search from E point to F point, Δ A is negative, and Δ f is just, eaf is negative, represent that Searching point is in antihunting face, otherwise search from F point to E point, Δ A is just, Δ f is negative, eaf is negative, and same expression Searching point is in antihunting face, and next step all should be searched for backward, step-size in search can be identical, adopt same fuzzy rule to determine, starting point is different, and Δ A is just, Δ f is negative, gets now state point E point and starts Searching point for next step; Δ A is negative, and Δ f is just, gets previous state point E point and starts Searching point for next step, that is:

f _k+1＝f _k-1+Δf _kΔf＞0,ΔA＜0

f _k+1＝f _k+Δf _kΔf＜0,ΔA＞0 (3)

Composite type (2) and formula (3),

f _k+1＝f _k-1+Δf _kΔA＜0

f _k+1＝f _k+Δf _kΔA＞0 (4)

According to analysis above, choose the input of ratio eaf as fuzzy self-adaption Resonant Frequency Tracking System of amplitude variations amount Δ A and corresponding frequency-tracking step delta f, can find out with reference to Fig. 2, only adopt an eaf value can not the state of certainty annuity completely, the complete certainty annuity frequency-tracking state of input variable ability that another describes trace point position must be increased.Resonance frequency based on fixed ampllitude is followed the tracks of and oscillating load amplitude jointly controls in strategy, should carry out frequency-tracking, carry out amplitude controlling again, and the amplitude-frequency response value of resonance point is constantly change.Therefore select absolute value bf another input quantity as fuzzy self-adaption Resonant Frequency Tracking System of the deviation of trace point and theoretical resonance point, then,

bf＝|f _theory-f _k| (5)

In formula, f _theoryfor natural frequency calculated value, f _kfor following the tracks of moment frequency values.Bf is larger, and to represent resonance point far away, bf close to 0, represent from resonance point just very close to.Adopt these two parameters can determine position residing for trace point and state as input quantity, then select suitable fuzzy subset and membership function, set up suitable fuzzy rule by fuzzy reasoning, determine adaptive frequency-tracking step-length.

Further, consider Crack Extension different phase, tuning-points skew is different, and Crack Extension initial stage Crack Extension is comparatively slow, can adopt less tracing step; Crack Extension Crack Extension in mid-term is very fast, can adopt larger tracing step; Crack Extension later stage Crack Extension is fast, can adopt large tracing step.Different fuzzy rules or domain to be adopted like this in Crack Extension different phase, so adopt two-layer supervised dual input list to export Fuzzy control system, concrete structure schematic diagram is with reference to Fig. 1, the output quantity of frequency tracing control device is except frequency-tracking step delta f, also should be taken into account because frequency-tracking is on the impact of amplitude-frequency response, increase by a frequency influence factor fa.

1.2) obfuscation of input and output amount

The input variable of frequency-tracking fuzzy controller has been selected to be adjacent two sampled point amplitude excursion Δ A and the ratio eaf of corresponding frequency-tracking step delta f and the absolute value of the bias bf of trace point and resonance point, output variable is tracking frequencies step delta f, and its corresponding Fuzzy Linguistic Variable is respectively EAF, BF and Δ F, according to many experiments situation, the basic domain of eaf is (-24,24), and the basic domain of fb is (0,20), the basic domain of Δ f is (-5,5), fuzzy variable EAF, fuzzy domain primary election corresponding to BF and Δ F is that domain basic with it is identical, and on its fuzzy domain, the fuzzy subset of EAF is negative large (NB), in negative (NM), negative little (NS), negative zero (NZ), positive zero (PZ), just little (PS), center (PM), honest (PB) fuzzy subset, namely the fuzzy subset of EAF=(PB, PM, PS, PZ, NZ, NS, NM, NB), BF is very near (PS), closely (PM), far (PB), namely the fuzzy subset of BF=(PB, PM, PS), Δ F is negative large (NB), in negative (NM), negative little (NS), negative zero (NZ), positive zero (PZ), just little (PS), center (PM), honest (PB) fuzzy subset, i.e. Δ F=(PB, PM, PS, PZ, NZ, NS, NM, NB).The degree of membership of each fuzzy subset is with reference to Fig. 3, Fig. 4, Fig. 5.The value of frequency influence factor fa is fairly simple, gets 0, and 1,2 three numerals describe the influence degree of frequency adjustment to amplitude controlling.

After the fuzzy subset of each fuzzy variable and membership function thereof have been selected, with reference to Fig. 6, vague description can be carried out to tracking mode, when trace point is B, trace point is positioned at that just to search for identity distance far from resonance point, and follows the tracks of to be in and slowly carry out state, then can be described as: BF is PB and EAF is PS, now should continue to follow the tracks of forward, and tracing step is large, i.e. Δ F=PB.When trace point is C, trace point is positioned at just searches for identity distance away from resonance point, and tracking is in very fast state, then can be described as: BF is PM and EAF is PM, now should continue to follow the tracks of forward, and tracing step is moderate, i.e. Δ F=PM.When trace point is D, trace point distance resonance point is very near, and tracking is in slower state, then can be described as: BF is PS and EAF is Z0, now finds resonance point, should stop following the tracks of, i.e. Δ F=Z0.For E point, trace point is positioned at negative search face and distance resonance point is moderate, and tracking is in very fast state, then can be described as: BF is PM and EAF is NM, now should continue to follow the tracks of backward, and tracing step is moderate, i.e. Δ F=NM.

1.3) formulation of fuzzy rule: to describe according to the fuzzy language of adopted fuzzy variable and fatigue crack propagation test natural frequency experience of following the tracks of sets up fuzzy rule as shown in table 1.

Table 1

The form of control law is:

R _k：if EAF is A _iand BF is B _j，then ΔF is C _m， (6)

Wherein, R _krepresent kth bar control language rule, k=1,2...24, A _irepresent the fuzzy language value of fuzzy variable EAF, i=1,2...8, B _jrepresent the fuzzy language value of fuzzy variable BF, j=1,2,3, C _mrepresent the fuzzy language value of fuzzy variable Δ F, m=1,2...9.

The computation rule of the factor of influence fa of frequency versus amplitude is:

if ΔF＝(PB,PM,NB,NM) fa＝2

if ΔF＝(PMS,PS,NMS,NS) fa＝1 (7)

if ΔF＝(ZO) fa＝0

1.4) fuzzy reasoning and defuzzification: the main body of frequency tracing control device is input quantity eaf and bf, output quantity is that two inputs of Δ F singly export fuzzy controller.Two inputs shown in employing formula (8) and formula (9) are single exports Mamdani MAX-MAN inference method, and de-fuzzy then adopts the gravity model appoach shown in formula (10) that precision is higher, and concrete fuzzy inference rule is as follows:

Rule 1:if A ₁and B ₁then C ₁

Rule 2:if A ₂and B ₂then C ₂

.........

Rule 3:if A _nand B _nthen C _n

Input x ₀and y ₀conclusion z ₀

By prerequisite " x ₀and y ₀" and various fuzzy rule " if A _iand B _ithen C _i(i=1,2...n) " can the reasoning results be obtained: the wall scroll rule of activation exports the fuzzy subset C of fuzzy variable _i' degree of membership such as formula shown in (8), the degree of membership of the fuzzy subset C' of total activation vagueness of regulations variable such as formula shown in (9), the output quantity z after defuzzification ₀such as formula (10).

${\mathrm{\μ}}_{{C_i}^{\′}}\left(z\right)={\mathrm{\μ}}_{A_i}\left(x_0\right)^{\mathrm{\μ}}_{B_i}\left(y_0\right)^{\mathrm{\μ}}_{C_i}\left(z\right)---\left(8\right)$

$z_0=\frac{\underset{i=1}{\overset{n}{\Σ}}{\mathrm{\μ}}_{C^{\′}}\left(z_i\right)z_i}{\underset{i=1}{\overset{n}{\Σ}}{\mathrm{\μ}}_{C^{\′}}\left(z_i\right)}---\left(10\right)$

The design of described resonance region amplitude controller, comprises with lower part:

2.1) obfuscation of input quantity and output quantity.

Amplitude mode fuzzy controllers be input as amplitude excursion e, deviation variation rate ec; Export the variation delta u of the exciting voltage for electromagnetic resonator, its corresponding Fuzzy Linguistic Variable is E, EC and Δ U, according to many experiments situation, the basic domain of e is (-25,25), the basic domain of ec is (-8,8), the basic domain of Δ u is (-5,5).The degree of membership of E, EC and each fuzzy subset of Δ U, with reference to Fig. 7, Fig. 8, Fig. 9.

2.2) foundation of fuzzy rule

The fuzzy rule of associating amplitude controller, change according to the difference of the frequency influence factor, frequency-tracking factor of influence has three numerical value 0,1,2.If system works is at resonance point, then factor of influence is 0; If be 1 close to the resonant enhance factor; As from resonance point slightly away from factor of influence be 2.According to the impact of frequency adjustment on each region of amplitude controller control law, draw and jointly control middle amplitude controlling three groups of fuzzy rule data, as table 2, table 3, table 4.

Table 2

Table 3

Table 4

2.3) fuzzy reasoning and defuzzification

Jointly control middle amplitude mode fuzzy controllers, adopt the fuzzy reasoning identical with frequency tracing control device and defuzzification rule, no longer repeat at this.

To follow the tracks of in order to the resonance frequency verifying based on fixed ampllitude and oscillating load amplitude jointly controls tactful control performance, built experiment porch have employed amplitude PID control method, the oscillating load amplitude of strategy process to fatigue crack propagation test that jointly control that amplitude mode fuzzy control method and the present invention propose control, and add the measurement function of dynamic control process parameter in the application: the overshoot amplitude in adjustment process, the measurement of regulation time.The systematic sampling time is 0.5 second, and for making experimental result have ubiquity, each method control performance parameter when measuring amplitude different settings, records specific experiment data with reference to table 5.Experimental result shows: provided by the inventionly jointly control strategy process and compare with amplitude PID control method, amplitude mode fuzzy control method, control accuracy is high, and (stable state accuracy is less than 1%, overshoot is less than 2%), regulation time is short, and control procedure is reliable and stable.

Table 5

Finally illustrate, above embodiment is only for patent spirit of the present invention explanation for example.Patent person of ordinary skill in the field of the present invention can make various amendment or supplements or adopt similar method to substitute to described specific embodiment, but can't depart from the spirit of patent of the present invention or surmount the scope that appended claims defines.

Claims (4)

1. the resonance frequency based on fixed ampllitude is followed the tracks of and oscillating load amplitude combined control system, it is characterized in that: described combined control system adopts double-deck fuzzy control system device structure, upper strata is supervision and management controller, by On Crack Propagation length, the monitoring in the controlling of sampling moment of load amplitude and resonance frequency, carry out the planning of frequency and amplitude controlling sequential and the calculating of controlling value and output to underlying frequency tracking control unit and resonance region amplitude controller, lower floor is frequency tracing control device and resonance region amplitude controller.

2. follow the tracks of and oscillating load amplitude combined control system based on the resonance frequency of fixed ampllitude as claimed in claim 1, it is characterized in that: described upper strata supervision and management controller be input as crack extending length and sampling instant, output has 3 classes: (1) is according to sampling instant, control load fuzzy controller activationary time, determines its controlling value exported and controls the moment; Controlled frequency fuzzy controller activationary time, determine its controlling value exported and control the moment, (2) according to the feature of gathered crack extending length and Crack Extension different phase, the domain of load fuzzy controller and frequency ambiguity controller is adjusted by adjustment quantized factor and proportional factor, principle is that Crack Extension initial stage Crack Extension is slower, amplitude variations is less, adopts little domain, less tracing step and less amplitude controlling amount; Crack Extension Crack Extension in mid-term is very fast, and amplitude variations is comparatively large, domain in employing, larger tracing step and larger amplitude controller; Crack Extension later stage Crack Extension is fast, and amplitude variations is large, adopts large domain, large tracing step and large amplitude controlling amount; (3) according to gathered crack extending length, the natural frequency value f of crack Propagation to system during this numerical value is calculated _theory, and by this value and now system operating frequency value f _ksubtract each other after taking absolute value and fuzzy controller input bf, bf must be multiplied by quantizing factor K ₁after be transformed into fuzzy domain, be input to fuzzy self-adaption resonance frequency tracking control unit.

3. follow the tracks of and oscillating load amplitude combined control system based on the resonance frequency of fixed ampllitude as claimed in claim 1 or 2, it is characterized in that: the process jointly controlled repeats two stages: from k-1 moment to the k moment with from the k moment to the control procedure in k+1 moment, (1) from the k-1 moment to the k moment: only carried out frequency-tracking, and do not carry out amplitude controlling by changing exciting voltage, the change of amplitude-frequency response is caused by frequency-tracking, the input quantity eaf of calculated rate tracking control unit and bf, eaf is the difference of amplitude-frequency response after frequency-tracking and the ratio of corresponding frequency-tracking step-length another inputs bf=|f _theory-f _k| the absolute value of moment frequency values and theoretical natural frequency deviation for this reason, calculates tracing step Δ f required for next step by frequency tracing control device _k, calculate down 2 moment rate-adaptive pacemaker f _k+2=f _k+ Δ f _k, export subsequent time frequency f _k+1=f _krate-adaptive pacemaker remains unchanged, the amplitude output valve adopting the k-1 moment to calculate carries out amplitude controlling, (2) from the k moment to the k+1 moment: be carry out amplitude controlling by changing exciting voltage, frequency remains unchanged, the change of amplitude-frequency response caused by amplitude controlling, the deviation e=r-A of the input quantity e of calculated amplitude controller and ec, e moment amplitude-frequency response and setting value for this reason _k, ec deviation variation rate next step control voltage variation delta U is calculated by amplitude mode fuzzy controllers _k, calculate down 2 moment voltages and export U _k+2=U _k+ Δ U _k, the subsequent time rate-adaptive pacemaker amount that output previous moment calculates carries out frequency-tracking, and the exciting voltage of subsequent time exports the U that remains unchanged _k+1=U _k.

4. follow the tracks of and oscillating load amplitude combined control system based on the resonance frequency of fixed ampllitude as claimed in claim 3, it is characterized in that: repeat the process from the k-1 moment to the k moment from the k+1 moment to the k+2 moment, the process from the k moment to the k+1 moment is repeated from the k+2 moment to the k+3 moment, be recycled to frequency and amplitude controlling completes always, if after frequency is adjusted to the right place, amplitude does not still arrive setting value, then carry out amplitude controlling continuously, as amplitude is adjusted to the right place and frequency does not adjust to resonance point, then frequency-tracking is followed the tracks of with minimum step 0.1Hz, amplitude controlling rule is constant, until find resonance point.