CN104298854A - Method and device for detecting complexity of signal - Google Patents

Abstract

The invention discloses a device and method for detecting the complexity of a signal. The device comprises a standard testing system, a performance estimator and a complexity calculator. The complexity detecting method is simple, and algorithm efficiency is high.

Description

A kind of method of signal complexity measure and device

Technical field

The invention belongs to the signal complexity measure technical field of control system, particularly relate to a kind of method and device of signal complexity measure.

Background technology

Signal is extensively present in the signal stream transmittance process of internal system, the measuring-signal etc. of the deviation signal of such as controller input end, the control signal of actuator input end, transmitter input.The complexity measure of signal plays an important role in the evaluation, fault diagnosis, medical treatment etc. of system performance.But most systems is nonlinear often in actual production process, make the whole signal stream in control system present nonlinear characteristic, the characteristic quantity being therefore difficult to extract effective signal from original signal carries out analysis of complexity to signal.Therefore signal complexity measure is the very important and work of necessity.

Summary of the invention

Technical scheme of the present invention is, a kind of method of signal complexity measure and pick-up unit, is characterized in that comprising standard test system, performance calculator, complicated dynamic behaviour device.

The connected mode that three parts are connected successively.Described standard test system is connected with performance calculator; Described performance calculator is connected with complicated dynamic behaviour device.

Measured signal obtains test by standard test system and exports, and test exports output performance counter calculation of performance indicators, and performance index enter the complicacy that complicated dynamic behaviour device calculates measured signal again.

A kind of signal complexity measure, is characterized in that the method comprises the following steps:

Step 1: using the setting value of signal r as described standard test macro, the closed-loop control through standard test system obtains its output y.

Step 2: described performance calculator exports y and signal r by described standard test macro and is poor tracking error e, is then calculated the performance index η of system under this signal r effect by tracking error e.

Step 3: described complicated dynamic behaviour device calculates the complexity C of signal r by performance index η.

Described modular system design is a closed-loop system comprising controller and controlled device.

Described performance calculator first error of calculation e is as follows:

e＝r-y (1)

Wherein: r is measured signal;

Y is the output of measured signal by described standard test system.

Performance index η herein elects the integration IAEP of unit interval Error Absolute Value as, being calculated as follows of this index:

$\mathrm{IAEP}=\frac{\underset{0}{\overset{T}{\∫}}\left|e\right|\mathrm{dt}}{T}---\left(2\right)$

T is the time span of measured signal.

Complexity C is calculated as follows:

$C=\frac{\mathrm{IAEP}}{T}---\left(3\right)$

Complexity of the present invention be greater than 0 value, its value is larger, then it shows that the complicacy of signal is higher.This complexity is from the reality controlled, and the result obtained is independent of control, only relevant to signal itself.

Accompanying drawing explanation

Fig. 1 signal complexity measurement apparatus schematic diagram;

The structural drawing of Fig. 2 standard test fixture;

The exploded view of the signal that Fig. 3 is general;

Embodiment

Below in conjunction with accompanying drawing, preferred embodiment is elaborated.It is emphasized that following explanation is only exemplary, instead of in order to limit the scope of the invention and apply.

The invention provides a kind of succinct, effectively, need priori few, be easy to calculate, multiple-input, multiple-output control system method for testing performance without impact and device normally run on actual control system.

For the complexity of detection signal, the invention provides method for testing performance and the device of multiple-input, multiple-output control system.As shown in Figure 1, the present invention mainly contains three Part compositions: standard test system, performance calculator, complicated dynamic behaviour device.The method and device are implemented as follows:

1. standard test system

Described standard test system is single-input single-output closed feedback loop as shown in Figure 2, and controller C (s) represents, controlled device P (s) represents.The transfer function model of described standard test system P (s) is expressed as follows:

$P\left(s\right)=\frac{K}{T_{1}s+1}{e}^{-\mathrm{\θs}}---\left(4\right)$

Wherein: s is Laplace operator;

K is static gain;

T ₁for inertia time constant;

θ is time delay.

Described standard test system controller C (s) is as follows:

$C\left(s\right)=K_p(1+\frac{1}{T_{i}s})---\left(5\right)$

Wherein: k _pfor controller scale-up factor;

T _ifor the integration time constant of controller.

Internal mold tuning rule is adopted to adjust as follows to controller parameter:

$K_p=\frac{T_1}{K(\mathrm{\λ}+\mathrm{\θ})},T_i=T_1---\left(6\right)$

λ represents the closed-loop time constant in internal model control, usually meets λ > θ.

2. performance calculator

The major function that performance calculates calculates the performance of system by formula (2).

3. complicated dynamic behaviour device

In working control process, a common signal as shown in Figure 3.Decomposition principle, a general command signal can be approximately decomposed into the array configuration of a series of ramp signal, and time interval t ₂-t ₁, t ₃-t ₂..., t _n-t _n-1less, degree of approximation is higher.That is:

r＝r ₁(t)+r ₂(t)+...+r _n(t) (7)

Wherein r _it i-th ramp signal that () decomposites for signal r;

According to the definition in this patent, the complexity of general signal is:

$C_{r\left(t\right)}=\frac{\mathrm{IAE}\left(r\left(t\right)\right)}{T}=\frac{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}\mathrm{IAE}\left(r_i\left(t\right)\right)}{T}=\frac{(\mathrm{\λ}+\mathrm{\θ})\underset{i=1}{\overset{n}{\mathrm{\Σ}}}\left|k_i\right|(t_i-t_{i-1})}{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}(t_i-t_{i-1})}---\left(8\right)$

θ is the delay of plant model, only relevant with the object of signal function, and has nothing to do with signal itself; λ is the closed-loop time constant in internal model control, and because standard test system controller parameter is determined according to its plant model parameter, utilize internal mold tuning rule to adjust to obtain, also the object of an and instruction signal function is relevant.Therefore, when analyzing the complexity of different instruction signal, if it acts in same controlled device, then the complexity of these instructions can be rewritten as:

$C=\frac{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}\left|k_i\right|(t_i-t_{i-1})}{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}(t_i-t_{i-1})}=\frac{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}|r\left(t_i\right)-r\left(t_{i-1}\right)|}{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}(t_i-t_{i-1})}---\left(9\right)$

Above formula is the complicated dynamic behaviour formula of discrete type signal.If the time interval is enough little, namely time, the computing formula of the complexity measure index of continuous type signal can be obtained:

$C=\frac{{\∫}_0^T\mathrm{ds}}{T}=\frac{L\left(r\left(t\right)\right)}{T}---\left(10\right)$

The length that L (r (t)) is continuous type signal.

The above; be only the present invention's preferably embodiment, but protection scope of the present invention is not limited thereto, is anyly familiar with those skilled in the art in the technical scope that the present invention discloses; the change that can expect easily or replacement, all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claim.

Claims (5)

1. a signal complexity measure device, is characterized in that this device comprises standard test system, performance calculator, complicated dynamic behaviour device;

Three parts of described device adopt the connected mode of connecting successively.Described standard test system is connected with performance calculator; Described performance calculator is connected with complicated dynamic behaviour device.

2. utilize a signal complexity measure for device described in claim 1, it is characterized in that the method comprises the following steps:

Step 1: using the setting value of signal r as described standard test macro, the closed-loop control through standard test system obtains its output y.

Step 2: described performance calculator exports y and signal r by described standard test macro and is poor tracking error e, is then calculated the performance index η of system under this signal r effect by tracking error e.

Step 3: described complicated dynamic behaviour device calculates the complexity C of signal r by performance index η.

3. signal complexity measure method according to claim 2, is characterized in that general complexity measure index is:

Wherein: IAEP is the integration of unit time error absolute value

T is the time span of measured signal.

4. a kind of control performance detection method according to claim 2 and the general complexity measure index described in claim 3, is characterized in that the computing formula of discrete type signal complexity measure index is:

Wherein: n is the number of discrete signal discrete point;

T _ifor the moment of signal i-th discrete point;

R (t _i) be the value of discrete signal i-th discrete point.

5. a kind of control performance detection method according to claim 2 and the general complexity measure index described in claim 3, is characterized in that the computing formula of continuous type signal complexity measure index is:

Wherein: the length that L (r (t)) is continuous type signal.