CN104836579A - Control device or method for preventing loop oscillation - Google Patents

Abstract

The invention relates to a control device and method for preventing loop oscillation, wherein the device comprises an adjusting performer, an analog-to-digital converter (ADC), a cost function detector, a loop filter, a control value regulator, and a digital-to-analog converter (DAC). The device also comprises a first processor, which is used for receiving a first parameter output by the cost function detector. A second parameter is obtained by performing first error correction according to the first parameter and is used for executing accuracy adjustment of the loop filter. The second parameter is output to the loop filter. The loop filter is used for receiving the second parameter and performs filter operation according to the second parameter.

Description

A kind of control device or method preventing loop oscillation

Technical field

The present invention relates to control technology, particularly relate to a kind of control device and the method that prevent loop oscillation.

Background technology

Present inventor, in the process realizing the embodiment of the present application technical scheme, at least finds to there is following technical problem in correlation technique:

Under the closed-loop control scene of digital receiver, in control loop, the precision of the adjusting actuator of analog domain is designated as the first precision, complete the analog signal of adjustment after analog to digital converter (ADC), digital signal is converted to by analog signal, through a series of processing execution to loop filter, the output accuracy of loop filter is designated as the second precision, export after controlling value adjuster adjusts, after digital to analog converter (DAC), be converted to analog signal by digital signal and be input to again in adjusting actuator.Wherein, in ADC and DAC, A refers to ANALOG, represents analog signal; D refers to DIGITAL, representative digit signal.

Due to through a series of process, perform and produce a series of error in the process of loop filter, or due to the requirement of closed-loop control itself, therefore, described second precision can there will be the unmatched situation of precision with described first precision, usually described second precision higher than described first precision, thus can cause the phenomenon of loop oscillation.Only the second higher precision is adjusted to the first lower precision, therefore can not reaches the effect of control loop vibration, in correlation technique, for this problem, not provide effective solution.

Summary of the invention

In view of this, the embodiment of the present invention, desirable to provide a kind of control device and the method that prevent loop oscillation, effectively can control loop oscillation, prevent loop oscillation phenomenon.

Technical scheme of the present invention is achieved in that

Prevent a control device for loop oscillation, described device comprises: adjusting actuator, analog to digital converter ADC, cost function detector, loop filter, controlling value adjuster, and digital to analog converter DAC, is characterized in that, described device also comprises:

First processor, for receiving the first parameter that described cost function detector exports, carrying out the first error correction according to described first parameter and obtaining the second parameter, and described second parameter is used for performing precision adjustment to described loop filter; Described second parameter is exported to described loop filter;

Accordingly, described loop filter, for receiving described second parameter, carries out filtering operation according to described second parameter.

Wherein, described device also comprises:

Second processor, obtains the 3rd parameter for carrying out the second error correction, and described 3rd parameter is used for performing precision adjustment to described loop filter; Described 3rd parameter is exported to described loop filter;

Accordingly, described loop filter, is further used for carrying out filtering operation according to described second parameter and described 3rd parameter.

Wherein, described first processor, being further used for described first parameter is e (n), and time e (n)=c (r (n)), adopt error amount normalization mode to carry out described first error correction, obtaining the second parameter is e ' (n); The computing adopting described error amount normalization mode to perform is:

$e^{\′}\left(n\right)=\left\{\begin{array}{c}e\left(n\right),\mathrm{abs}\left(e\left(n\right)\right)>\mathrm{step};\\ 0,\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator, and abs represents signed magnitude arithmetic(al).

Wherein, described second processor, be further used for receiving described loop filter and carry out the first output valve that described filtering operation obtains, and receive described controlling value adjuster and carry out controlling to adjust the second output valve of obtaining, described first output valve is f (n), and described second output valve is lf _ctime (n), according to described f (n) and described lf _cn (), adopts controlling value process and the mode resetting the integrated value in loop filter carries out described second error correction, and obtaining the 3rd parameter is lf ' (n-1); Adopt described controlling value process and the computing that the mode resetting the integrated value in loop filter performs is:

${\mathrm{lf}}^{\′}\left(n\right)=\left\{\begin{array}{c}{\mathrm{lf}}_C\left(n\right)+\frac{\mathrm{step}}{2},{\mathrm{lf}}_C\left(n\right)\≠{\mathrm{lf}}_C(n-1)\\ \mathrm{lf}\left(n\right),\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator.

Wherein, described loop filter, be further used for carrying out filtering operation according to described e ' (n) and described lf ' (n-1), performed computing is:

lf(n)=lf′(n-1)+f*e′(n)。

A kind of control method preventing loop oscillation, described method is applied to the control device preventing loop oscillation, described control device comprises adjusting actuator, analog to digital converter ADC, cost function detector, loop filter, controlling value adjuster, digital to analog converter DAC, it is characterized in that, described method comprises when described control device also comprises first processor:

First processor receives the first parameter that described cost function detector exports, and carries out the first error correction obtain the second parameter according to described first parameter, and described second parameter is used for performing precision adjustment to described loop filter; Described second parameter is exported to described loop filter;

Loop filter receives described second parameter, carries out filtering operation according to described second parameter.

Wherein, described method comprises when described control device also comprises the second processor:

Second processor carries out the second error correction and obtains the 3rd parameter, and described 3rd parameter is used for performing precision adjustment to described loop filter; Described 3rd parameter is exported to described loop filter;

Loop filter carries out filtering operation according to described second parameter and described 3rd parameter.

Wherein, describedly carry out the first error correction according to described first parameter and obtain the second parameter, specifically comprise:

Described first parameter is e (n), and time e (n)=c (r (n)), adopt error amount normalization mode to carry out described first error correction, obtaining the second parameter is e ' (n); The computing adopting described error amount normalization mode to perform is:

$e^{\′}\left(n\right)=\left\{\begin{array}{c}e\left(n\right),\mathrm{abs}\left(e\left(n\right)\right)>\mathrm{step}\\ 0,\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator, and abs represents signed magnitude arithmetic(al).

Wherein, described in carry out the second error correction and obtain the 3rd parameter, specifically comprise:

Described second processor receives described loop filter and carries out the first output valve that described filtering operation obtains, and receive described controlling value adjuster and carry out controlling to adjust the second output valve of obtaining, described first output valve is f (n), and described second output valve is lf _ctime (n), according to described f (n) and described lf _cn (), adopts controlling value process and the mode resetting the integrated value in loop filter carries out described second error correction, and obtaining the 3rd parameter is lf ' (n-1); Adopt described controlling value process and the computing that the mode resetting the integrated value in loop filter performs is:

${\mathrm{lf}}^{\′}\left(n\right)=\left\{\begin{array}{c}{\mathrm{lf}}_C\left(n\right)+\frac{\mathrm{step}}{2},{\mathrm{lf}}_C\left(n\right)\≠{\mathrm{lf}}_C(n-1)\\ \mathrm{lf}\left(n\right),\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator.

Wherein, describedly carry out filtering operation according to described second parameter and described 3rd parameter, specifically comprise:

Loop filter carries out filtering operation according to described e ' (n) and described lf ' (n-1), and performed computing is:

lf(n)=lf′(n-1)+f*e′(n)。

The control device of the embodiment of the present invention comprises: adjusting actuator, ADC, cost function detector, loop filter, controlling value adjuster, DAC, described device also comprises first processor, the first parameter that first processor exports for receiving described cost function detector, carry out the first error correction according to described first parameter and obtain the second parameter, described second parameter is used for performing precision adjustment to described loop filter; Described second parameter is exported to described loop filter; Accordingly, described loop filter, for receiving described second parameter, carries out filtering operation according to described second parameter.

The parameter of carrying out filtering operation due to loop filter is the second parameter obtained through the first error correction, therefore, can eliminate error, effectively control loop oscillation, can prevent the loop oscillation phenomenon that error causes.

Accompanying drawing explanation

Fig. 1 is the control device structural representation of control loop in prior art digital receiver;

Fig. 2 is the oscillatory occurences schematic diagram in existing digital AGC loop;

Fig. 3 is the oscillatory occurences schematic diagram of existing AGC loop under ETU70 channel;

Fig. 4 is the control device structural representation of the embodiment of the present invention;

Fig. 5 is the control method flow chart of the embodiment of the present invention;

Fig. 6 is the control device structural representation of the concrete scene of the embodiment of the present invention one;

Fig. 7 is that the embodiment of the present invention is for the dead-beat phenomenon schematic diagram under static channel scene;

Fig. 8 is that the embodiment of the present invention is for exporting the dead-beat phenomenon schematic diagram under scene under ETU70 channel.

Embodiment

Be described in further detail below in conjunction with the enforcement of accompanying drawing to technical scheme.

Be described for the closed-loop control scene of digital receiver, in the digital receiver of communication system, a kind of existing digital newspaper industry loop as shown in Figure 1, comprise adjusting actuator 01, ADC02, cost function detector 03, loop filter 04, controlling value adjuster 05, digital to analog converter DAC06.In Fig. 1, be designated as the first precision, represent with step in the precision of the adjusting actuator of analog domain, the analog signal r (t) completing adjustment is digital signal r (n) after ADC, and error-detecting exports and is:

e(n)=c(r(n)) （1）

In formula (1), described c (r (n)) is take described digital signal r (n) as the cost function of input, different according to the difference of closed-loop control target, while cost function output there is error, its output variance is in control loop, existing loop filter realizes by an integrator, such as, export to be:

lf(n)=lf(n-1)+f*e(n) （2）

In formula (2), f is the loop filter factor and f<1.

Existing controlling value adjuster is realized by controlling value Tuning function, and after the process of existing controlling value adjuster, the output of controlling value adjustment is:

${\mathrm{lf}}_C\left(n\right)=\mathrm{floor}\left(\frac{\mathrm{lf}\left(n\right)}{\mathrm{step}}\right)*\mathrm{step}---\left(3\right)$

In formula (3), floor (x) represents the maximum integer of getting <=x, also can replace floor (x) with round (x) or ceil (x).Due to through a series of process, perform and produce a series of error in the process of loop filter, or due to the requirement of closed-loop control own, therefore, described second precision can there will be the unmatched situation of precision with described first precision, in order to eliminate the unmatched situation of precision, so introduce controlling value adjuster, the object of controlling value Tuning function is that high-precision loop filter is exported the partial removal exceeding analog domain adjusting actuator precision step in lf (n).

Existing digital loop control loop filter bandwidth shown in Fig. 1 is only limited to loop filter factor f: τ=1/f and represents that the time constant that change is got on e (n) rank followed the tracks of by this loop filter.For departure output variance on the impact of control loop, f generally gets <<1, thus cause the precision of lf (n) to be f*step<<step, so controlling value Tuning function is essential in digital control loop, as shown in Equation (3).

The precision exporting lf (n) just because of loop filter is greater than the precision step of analog domain adjusting actuator, and is tending towards 0 along with convergence e (n) of control loop, and causes lf (n) to be converged in lf _cnear (n).Even if now also can lf be caused when the value being less than step appears in e (n) _cn () is in the vibration of convergency value place appearance ± step.Fig. 2 illustrates the oscillatory occurences of conventional digital control loop for AGC loop: in Fig. 2, adjusting actuator is the amplifier of gain controllable, its gain control accuracy step=1dB; E (n) after loop convergence=c (r (n))=meanpower (r (n))-powertarget=± 0.5dB; Get loop filter factor f=0.04.

Even if controlling value adjuster introduced by existing control device, still cannot solve precision and not mate the loop oscillation problem caused, once there is loop oscillation problem, may judge by accident is that loop self breaks down, not that loop breaks down in fact, and be only that precision is not mated.For this reason, embodiments provide following control program, can settle the matter once and for all, avoid precision not mate the loop oscillation caused, avoid erroneous judgement, but the embodiment of the present invention is not limited to the closed-loop control scene of digital receiver.For the closed-loop control scene of digital receiver, can be greater than to numeric field loop filter output accuracy in digital closed control loop oscillatory occurences that analog domain adjusting actuator degree of regulation causes and propose a kind of better simply scheme and remove this phenomenon.

As shown in Figure 4, the control device of loop oscillation that prevents of the embodiment of the present invention comprises:

Adjusting actuator 11, the analog to digital converter ADC12 analog signal that adjusting actuator 11 exports being converted to digital signal, the cost function detector 13 digital signal that ADC12 exports being carried out cost function computing, the parameter exported according to cost function detector 13 carry out filtering operation loop filter 14, loop filter 14 is exported to the controlling value adjuster 15 regulated, the digital signal carrying out controlling value adjuster 15 to control adjustment computing output is converted to the digital to analog converter DAC16 of analog signal.

Described device also comprises: first processor 17, first processor 17 is connected with cost function detector 13, for receiving the first parameter that cost function detector 13 exports, carry out the first error correction according to described first parameter and obtain the second parameter, described second parameter is used for performing precision adjustment to loop filter 14; Described second parameter is exported to loop filter 14.Accordingly, loop filter 14, is connected with first processor 17, for receiving described second parameter, carries out filtering operation according to described second parameter.

In the present invention one preferred implementation, as shown in Figure 4, the control device of loop oscillation that prevents of the embodiment of the present invention also comprises: the second processor 18, second processor 18 obtains the 3rd parameter for carrying out the second error correction, and described 3rd parameter is used for performing precision adjustment to loop filter 14; Described 3rd parameter is exported to loop filter 14.Accordingly, loop filter 14 is for carrying out filtering operation according to described second parameter and described 3rd parameter.

In the present invention one preferred implementation, as shown in Figure 4, first processor 17 is e (n) for described first parameter, and time e (n)=c (r (n)), adopt error amount normalization mode to carry out described first error correction, obtaining the second parameter is e ' (n); The computing adopting described error amount normalization mode to perform is:

$e^{\&prime;}\left(n\right)=\left\{\begin{array}{c}e\left(n\right),\mathrm{abs}\left(e\left(n\right)\right)>\mathrm{step}\\ 0,\mathrm{others}\end{array}\right.---\left(4\right)$

" 0, others " in above-mentioned formula (4) being described, referring to when not meeting abs (e (n)) >step, e ' (n)=0.

Wherein, described step is the precision of described adjusting actuator, and abs represents signed magnitude arithmetic(al).

In the present invention one preferred implementation, as shown in Figure 4, second processor 18 is connected with described controlling value adjuster respectively with described loop filter, the first output valve that described filtering operation obtains is carried out for receiving loop filter 14, and reception controlling value adjuster 15 carries out controlling to adjust the second output valve obtained, described first output valve is f (n), and described second output valve is lf _ctime (n), according to described f (n) and described lf _cn (), adopts controlling value process and the mode resetting the integrated value in loop filter carries out described second error correction, and obtaining the 3rd parameter is lf ' (n-1); Adopt described controlling value process and the computing that the mode resetting the integrated value in loop filter performs is:

${\mathrm{lf}}^{\&prime;}\left(n\right)=\left\{\begin{array}{c}{\mathrm{lf}}_C\left(n\right)+\frac{\mathrm{step}}{2},{\mathrm{lf}}_C\left(n\right)\&NotEqual;{\mathrm{lf}}_C(n-1)\\ \mathrm{lf}\left(n\right),\mathrm{others}\end{array}\right.---\left(5\right)$

" lf (n), others " in above-mentioned formula (5) is described, refers to and do not meeting lf _c(n) ≠ lf _c(n-1) when, f ' (n)=lf (n).

Wherein, described step is the precision of described adjusting actuator.

In the present invention one preferred implementation, loop filter 14 is for carrying out filtering operation according to described e ' (n) and described lf ' (n-1), and performed computing is:

lf(n)=lf′(n-1)+f*e′(n) （6）

As shown in Figure 5, the control method of loop oscillation that prevents of the embodiment of the present invention is applied to the control device preventing loop oscillation shown in Fig. 4, described control device comprises adjusting actuator, analog to digital converter ADC, cost function detector, loop filter, controlling value adjuster, digital to analog converter DAC, when described control device also comprises first processor, said method comprising the steps of:

Step 101, first processor receive the first parameter that described cost function detector exports, and carry out the first error correction obtain the second parameter according to described first parameter, and described second parameter is used for performing precision adjustment to described loop filter; Described second parameter is exported to described loop filter.

Step 102, loop filter receive described second parameter, carry out filtering operation according to described second parameter.

In the present invention one preferred implementation, carry out the first error correction according to described first parameter in step 101 and obtain the second parameter and specifically comprise:

Described first parameter is e (n), and time e (n)=c (r (n)), adopt error amount normalization mode to carry out described first error correction, obtaining the second parameter is e ' (n); The computing adopting described error amount normalization mode to perform is:

$e^{\&prime;}\left(n\right)=\left\{\begin{array}{c}e\left(n\right),\mathrm{abs}\left(e\left(n\right)\right)>\mathrm{step}\\ 0,\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator, and abs represents signed magnitude arithmetic(al).

In the present invention one preferred implementation, when described control device also comprises the second processor, described method also comprises further error correction, comprises the following steps:

Step 201, the second processor carry out the second error correction and obtain the 3rd parameter, and described 3rd parameter is used for performing precision adjustment to described loop filter; Described 3rd parameter is exported to described loop filter.

Step 202, loop filter carry out filtering operation according to described second parameter and described 3rd parameter.

In the present invention one preferred implementation, carry out the second error correction in step 201 and obtain the 3rd parameter and specifically comprise:

Described second processor receives described loop filter and carries out the first output valve that described filtering operation obtains, and receive described controlling value adjuster and carry out controlling to adjust the second output valve of obtaining, described first output valve is f (n), and described second output valve is lf _ctime (n), according to described f (n) and described lf _cn (), adopts controlling value process and the mode resetting the integrated value in loop filter carries out described second error correction, and obtaining the 3rd parameter is lf ' (n-1); Adopt described controlling value process and the computing that the mode resetting the integrated value in loop filter performs is:

${\mathrm{lf}}^{\&prime;}\left(n\right)=\left\{\begin{array}{c}{\mathrm{lf}}_C\left(n\right)+\frac{\mathrm{step}}{2},{\mathrm{lf}}_C\left(n\right)\&NotEqual;{\mathrm{lf}}_C(n-1)\\ \mathrm{lf}\left(n\right),\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator.

In the present invention one preferred implementation, step 202 specifically comprises:

Loop filter carries out filtering operation according to described e ' (n) and described lf ' (n-1), and performed computing is:

lf(n)=lf′(n-1)+f*e′(n)。Be described the embodiment of the present invention for the closed-loop control scene of digital receiver below, control device comprises first processor and the second processor simultaneously.

The device of the embodiment of the present invention is as shown in Figure 6 relative to Fig. 1, add first processor and the second processor, under this scene, described first processor specifically adopts error normalized function to realize, described second processor specifically adopts controlling value process and resets integrated value two functions in loop filter and realizes, and processes the value that former error exports e (n) and loop filter output lf (n) respectively.The error in a part of loop can be eliminated by the process of first processor, and then better can remove error in conjunction with the process of the second processor, thus make after first processor and the second processor control treatment, the first precision is designated as in the precision of the adjusting actuator by analog domain, and the output accuracy of loop filter is when being designated as the second precision, eliminate precision and do not mate the loop oscillation caused, avoid erroneous judgement.

Wherein, adopt first processor, perform normalization Error processing and export as above-mentioned formula (4):

$e^{\&prime;}\left(n\right)=\left\{\begin{array}{c}e\left(n\right),\mathrm{abs}\left(e\left(n\right)\right)>\mathrm{step}\\ 0,\mathrm{others}\end{array}\right.$

By the control treatment of first processor, adopt above-mentioned formula (4) to process e (n), be conducive to the adjustment that loop controls.

Wherein, adopt the second processor, perform controlling value process with above-mentioned formula (5) and to reset in loop filter integrated value and export and be:

${\mathrm{lf}}^{\&prime;}\left(n\right)=\left\{\begin{array}{c}{\mathrm{lf}}_C\left(n\right)+\frac{\mathrm{step}}{2},{\mathrm{lf}}_C\left(n\right)\&NotEqual;{\mathrm{lf}}_C(n-1)\\ \mathrm{lf}\left(n\right),\mathrm{others}\end{array}\right.$

Adopt above-mentioned formula (6), now loop filter exports and is modified to:

lf(n)=lf′(n-1)+f*e′(n)

By the control treatment of the second processor, adopt above-mentioned formula (5) and (6) to process lf (n), the lf (n) obtained after revising, be more conducive to the adjustment that loop controls.

Under this scene, adopt the embodiment of the present invention, for AGC loop, Fig. 2 is the oscillatory occurences schematic diagram in existing digital AGC loop, Fig. 7 be the embodiment of the present invention for the dead-beat phenomenon schematic diagram under static channel scene, and use the embodiment of the present invention to obtain under Fig. 2 similarity condition controlling value adjustment export lfc (n) as shown in Figure 7, can intuitively find out as shown in Figure 7: owing to being tending towards the first precision through adjusting the second precision, therefore, loop oscillation is not obvious.Under ETU70 channel, the loop of prior art is adopted to control and embodiment of the present invention loop controls the simulation result that obtains respectively as shown in figures 3 and 8, Fig. 3 is the oscillatory occurences schematic diagram of existing AGC loop under ETU70 channel, Fig. 8 is that the embodiment of the present invention is for exporting the dead-beat phenomenon schematic diagram under scene under ETU70 channel, remove in Fig. 3 and Fig. 8 channel condition and Fig. 2 different outside, other parameter is all consistent.Can intuitively find out as shown in Figure 8: owing to being tending towards the first precision through adjusting the second precision, therefore, loop oscillation is not obvious.

If module integrated described in the embodiment of the present invention using the form of software function module realize and as independently production marketing or use time, also can be stored in a computer read/write memory medium.Based on such understanding, the technical scheme of the embodiment of the present invention can embody with the form of software product the part that prior art contributes in essence in other words, this computer software product is stored in a storage medium, comprises some instructions and performs all or part of of method described in each embodiment of the present invention in order to make a computer equipment (can be personal computer, server or the network equipment etc.).And aforesaid storage medium comprises: USB flash disk, portable hard drive, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disc or CD etc. various can be program code stored medium.Like this, the embodiment of the present invention is not restricted to any specific hardware and software combination.

Accordingly, the embodiment of the present invention also provides a kind of computer-readable storage medium, wherein stores computer program, and this computer program is for performing the control method preventing loop oscillation of the embodiment of the present invention.

The above, be only preferred embodiment of the present invention, be not intended to limit protection scope of the present invention.

Claims (10)

1. prevent a control device for loop oscillation, described device comprises: adjusting actuator, analog to digital converter ADC, cost function detector, loop filter, controlling value adjuster, and digital to analog converter DAC, is characterized in that, described device also comprises:

First processor, for receiving the first parameter that described cost function detector exports, carrying out the first error correction according to described first parameter and obtaining the second parameter, and described second parameter is used for performing precision adjustment to described loop filter; Described second parameter is exported to described loop filter;

Accordingly, described loop filter, for receiving described second parameter, carries out filtering operation according to described second parameter.

2. device according to claim 1, is characterized in that, described device also comprises:

Second processor, obtains the 3rd parameter for carrying out the second error correction, and described 3rd parameter is used for performing precision adjustment to described loop filter; Described 3rd parameter is exported to described loop filter;

Accordingly, described loop filter, is further used for carrying out filtering operation according to described second parameter and described 3rd parameter.

3. device according to claim 2, it is characterized in that, described first processor, being further used for described first parameter is e (n), and time e (n)=c (r (n)), adopt error amount normalization mode to carry out described first error correction, obtaining the second parameter is e ' (n); The computing adopting described error amount normalization mode to perform is:

$e^{\&prime;}\left(n\right)=\left\{\begin{array}{c}e\left(n\right),\mathrm{abs}\left(e\left(n\right)\right)>\mathrm{step}\\ 0,\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator, and abs represents signed magnitude arithmetic(al).

4. device according to claim 3, it is characterized in that, described second processor, be further used for receiving described loop filter and carry out the first output valve that described filtering operation obtains, and receive described controlling value adjuster and carry out controlling to adjust the second output valve of obtaining, described first output valve is f (n), and described second output valve is lf _ctime (n), according to described f (n) and described lf _cn (), adopts controlling value process and the mode resetting the integrated value in loop filter carries out described second error correction, and obtaining the 3rd parameter is lf ' (n-1); Adopt described controlling value process and the computing that the mode resetting the integrated value in loop filter performs is:

${\mathrm{lf}}^{\&prime;}\left(n\right)=\left\{\begin{array}{c}{\mathrm{lf}}_C\left(n\right)+\frac{\mathrm{step}}{2},{\mathrm{lf}}_C\left(n\right)\&NotEqual;{\mathrm{lf}}_C(n-1)\\ \mathrm{lf}\left(n\right),\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator.

5. device according to claim 4, is characterized in that, described loop filter, is further used for carrying out filtering operation according to described e ' (n) and described lf ' (n-1), and performed computing is:

lf(n)=lf′(n-1)+f*e′(n)。

6. one kind prevents the control method of loop oscillation, it is characterized in that, described method is applied to the control device preventing loop oscillation, described control device comprises adjusting actuator, analog to digital converter ADC, cost function detector, loop filter, controlling value adjuster, digital to analog converter DAC, it is characterized in that, described method comprises when described control device also comprises first processor:

First processor receives the first parameter that described cost function detector exports, and carries out the first error correction obtain the second parameter according to described first parameter, and described second parameter is used for performing precision adjustment to described loop filter; Described second parameter is exported to described loop filter;

Loop filter receives described second parameter, carries out filtering operation according to described second parameter.

7. device according to claim 6, is characterized in that, described method comprises when described control device also comprises the second processor:

Second processor carries out the second error correction and obtains the 3rd parameter, and described 3rd parameter is used for performing precision adjustment to described loop filter; Described 3rd parameter is exported to described loop filter;

Loop filter carries out filtering operation according to described second parameter and described 3rd parameter.

8. device according to claim 7, is characterized in that, describedly carries out the first error correction according to described first parameter and obtains the second parameter, specifically comprises:

Described first parameter is e (n), and time e (n)=c (r (n)), adopt error amount normalization mode to carry out described first error correction, obtaining the second parameter is e ' (n); The computing adopting described error amount normalization mode to perform is:

$e^{\&prime;}\left(n\right)=\left\{\begin{array}{c}e\left(n\right),\mathrm{abs}\left(e\left(n\right)\right)>\mathrm{step}\\ 0,\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator, and abs represents signed magnitude arithmetic(al).

9. method according to claim 8, is characterized in that, described in carry out the second error correction and obtain the 3rd parameter, specifically comprise:

Described second processor receives described loop filter and carries out the first output valve that described filtering operation obtains, and receive described controlling value adjuster and carry out controlling to adjust the second output valve of obtaining, described first output valve is f (n), and described second output valve is lf _ctime (n), according to described f (n) and described lf _cn (), adopts controlling value process and the mode resetting the integrated value in loop filter carries out described second error correction, and obtaining the 3rd parameter is lf ' (n-1); Adopt described controlling value process and the computing that the mode resetting the integrated value in loop filter performs is:

${\mathrm{lf}}^{\&prime;}\left(n\right)=\left\{\begin{array}{c}{\mathrm{lf}}_C\left(n\right)+\frac{\mathrm{step}}{2},{\mathrm{lf}}_C\left(n\right)\&NotEqual;{\mathrm{lf}}_C(n-1)\\ \mathrm{lf}\left(n\right),\mathrm{others}\end{array}\right.;$ Wherein, described step is the precision of described adjusting actuator.

10. method according to claim 9, is characterized in that, describedly carries out filtering operation according to described second parameter and described 3rd parameter, specifically comprises:

Loop filter carries out filtering operation according to described e ' (n) and described lf ' (n-1), and performed computing is:

lf(n)=lf′(n-1)+f*e′(n)。