CN103809445B - Aircraft multiloop model bunch Composite PID controller design method - Google Patents

Abstract

The invention provides a kind of aircraft multiloop model bunch Composite PID controller design method, the method directly determines by frequency sweep flight test the model cluster that the amplitude-frequency that obtains in full envelope curve and phase-frequency characteristic form under given differing heights, Mach number condition; Directly determine open loop cut-off frequency interval according to the amplitude versus frequency characte in flight envelope; Directly determine and the interval corresponding phase margin of cut-off frequency interval according to the phase-frequency characteristic in flight envelope; Determine multistage PID controller sum of series parameter value by adding the identification Method in multistage PID controller phase margin index and System Discrimination in the full envelope curve of aircraft; Magnitude margin index in the full flight envelope of aircraft

Description

Aircraft multiloop model bunch Composite PID controller design method

Technical field

The present invention relates to a kind of controller of aircraft method for designing, particularly aircraft multiloop model bunch Composite PIDController design method, belongs to the category such as observation and control technology and flight mechanics.

Background technology

The control of aircraft landing process plays an important role to flight safety; Due to flying speed in aircraft landing processChange greatly, even also can face strong nonlinearity problem according to longitudinal model; On the other hand, the control vane of aircraft exist saturated,The phenomenons such as dead band; Consider from flight safety, when hedgehopping (as take off/land), controller must ensure system toolThere are certain stability margin, non-overshoot and stationarity, like this, just make the design of hedgehopping controller very complicated, can notDirectly apply mechanically existing control theory and carry out the design of aircraft control.

In the design of modern practical flight controller, a small part adopts state space method to design, and most ofStill adopt the classical frequency domain method taking PID as representative and carry out controller against Nyquist Array Method as the modern frequency method of representativeDesign. Modern control theory is taking state space method as feature, taking analytical Calculation as Main Means, to realize performance indications forExcellent modern control theory, has then developed again method for optimally controlling, model reference control method, self-adaptation control method, movingState is against control method, feedback linearization method, directly nonlinear optimization control, variable-gain control method, neural network control method,Fuzzy control method, a series of controller design methods such as robust control method and several different methods combination control, the science of deliveringPaper is ten hundreds of, and for example GhasemiA in 2011 has designed the reentry vehicle (Ghasemi of Adaptive Fuzzy Sliding Mode ControlA,MoradiM,MenhajMB.AdaptiveFuzzySlidingModeControlDesignforaLow-LiftReentryVehicle[J].JournalofAerospaceEngineering,2011,25(2):210-216), BabaeiAR in 2013 is that non-minimum phase and Nonlinear Flight device have designed fuzzy sliding mode tracking control automatic PilotInstrument (BabaeiAR, MortazaviM, MoradiMH.FuzzyslidingmodeautopilotdesignfornonminimumphaseandnonlinearUAV[J].JournalofIntelligentandFuzzySystems, 2013,24 (3): 499-509), a lot of research only rests on the Utopian simulation study stage; And thisPlant design and have three problems: (1), owing to cannot carrying out the extreme low-altitude handling and stability experiment of aircraft, is difficult to obtain accurateThe Mathematical Modeling of controlled device; (2) important performance of the evaluation flight control systems such as the stability margin specifying for army's mark refers toMark, state space method far can be expressed with obvious form unlike classical frequency method; (3) controller architecture is too multipleAssorted, not consider working control device and state of flight constraint, the controller of design physically can not be realized.

The scholar Rosenbrock of Britain has studied and how frequency domain method has been generalized to multi-variable system systematically, in a creative wayDesign in go, utilize matrix diagonal dominance concept, Multivariable is converted into the list of the classical approach that can know with people, in succession there is Mayne sequence return difference method, MacFarlane System with Characteristic Locus Method, Owens in the design problem of variable system laterThe methods such as dyadic expansion, common feature is the design of serious associated multi-variable system between many input more than one outputs, loop,Turn to the design problem of a series of single-variable systems, and then can select a certain classical approach (frequency of Nyquist and BodeResponse method, the root-locus technique of Evans etc.) design of completion system, above-mentioned these methods retain and have inherited classic graphic-arts techniqueAdvantage, do not require especially accurate Mathematical Modeling, easily meet the restriction in engineering. Particularly there is figure to show when adoptingWhen the conversational computer-aided design system of people's one machine of terminal is realized, can give full play to designer's experience and wisdom,Designing and both meet quality requirements, is again controller physically attainable, simple in structure; Both at home and abroad to multivariable frequencyMethod carried out improving research (tall and big far away, Luo Cheng, Shen Hui, Hu Dewen, Flexible Satellite Attitude solution lotus root controller multivariable is frequentlyRate territory method for designing, aerospace journal, 2007, Vol.28 (2), pp442-447; Xiong Ke, Xia Zhixun, Guo Zhenyun, banked turnHypersonic cruise vehicle multivariable frequency domain approach Decoupling design, plays arrow and guidance journal, 2011, Vol.31 (3), pp25-28) still, this method for designing conservative in the time of taking into account system uncertain problem is excessive, under aircraft control vane limited caseCan not obtain rational design result.

In sum, current control method can't change at dummy vehicle, stable according in full flight envelopeNargin index Design goes out that overshoot is little, low-latitude flying controller stably.

Summary of the invention

Can not in the situation that changing greatly, full flight envelope inner model design at aircraft symbol in order to overcome existing methodThe technological deficiency of little, the steady low-latitude flying controller of overshoot that closes the stability margin index in full flight envelope, the present invention carriesSupplied a kind of aircraft multiloop model bunch Composite PID controller design method, the method given differing heights, Mach severalUnder part, directly determine by frequency sweep flight test the model cluster that the amplitude-frequency that obtains in full envelope curve and phase-frequency characteristic form; According to flightAmplitude versus frequency characte in envelope curve is directly determined open loop cut-off frequency interval; Directly determine and cut according to the phase-frequency characteristic in flight envelopeThe only corresponding phase margin of frequency separation interval; By adding multistage PID controller the phase place in the full envelope curve of aircraftIdentification Method in nargin index and System Discrimination is determined multistage PID controller sum of series parameter value; Entirely fly at aircraftMagnitude margin index in row envelope curveDecibels is to carrying out controller's effect checking under stable condition; Abundant from phase margin and amplitudeThe concept of degree is set out to design and is met that the overshoot of full flight envelope is little, low-latitude flying controller stably.

The technical solution adopted for the present invention to solve the technical problems: a kind of aircraft multiloop model bunch Composite PID controlDevice method for designing processed, its feature comprises the following steps:

In the full envelope curve directly being flown by permission by frequency sweep flight test under step 1, given differing heights, Mach numberPrimary control surface in amplitude-frequency and the full envelope curve of phase-frequency characteristic formation aircraft and the model cluster of flying height, and can cross over flightEnvelope curve obtains the flutter frequency of aircraft, obtains open-loop transfer function mould between corresponding aircraft primary control surface and flying heightType bunch matrix is:

Wherein,ForSquare formation,For positive integer,For the independent variable of Laplace transformation,For aircraftFlying height,For Mach number,ForSingle mode square formation,ForMultinomial diagonal matrix,ForSingleMould square formation,For multinomial,For positive integer;

Choose

Satisfy condition:

And

Wherein,ForSquare formation,ForSingle mode square formation,ForMultinomial diagonal matrix,For?Row, theColumn element,For?Row, theColumn element,,ForSingle mode square formation,For multinomial,For phase angle mathematic sign;

The controller of aircraft multiloop system is made as:

Wherein,ForSquare formation,ForDiagonal matrix;For?Row, theColumn element,；

Step 2, controller，Design process as follows:

(1) order, the form of embodying is:

Wherein

、

For multinomialFormula,For the variable after laplace transform conventional in transfer function,Be respectively flying height and Mach number,The time delay of pitch channel,For withThe gain changing,For multinomialIn withThe coefficient bunch changing,For multinomialIn withThe coefficient bunch changing;

(2) directly determine that according to the amplitude versus frequency characte in flight envelope the interval definite method of open loop cut-off frequency is:

From?In, obtain open loop cut-off frequencySeparateMaximumAnd minimum of a value, open loop cut-off frequencyInterval is;

In formula,For the variable in frequency characteristic,For imaginary part represents,For angular frequency;

(3), according to the phase-frequency characteristic in flight envelope, calculate maximum phase nargin in envelope curve，

With minimum phase nargin in envelope curve

，

；

Directly determine with the interval corresponding phase margin of cut-off frequency interval and be:；

(4) transfer function of the multistage PID controller of candidate is:

In formula, N is integer, represents the progression of multistage PID controller to be determined,、、 For constant to be determined;

Add after multistage PID controller,

From?

In, obtain open loop cutoff frequencyRateThe maximum of separatingAnd minimum of a value, open loop cut-off frequencyInterval is，

Phase margin index in the full envelope curve of aircraftUnder stable condition, add system after multistage PID controllerPhase marginShould meet:

Meet:

Under These parameters and the common constraint of maximum likelihood criterion, according to the maximum likelihood side in system model Structure IdentificationMethod is determined progression N, the constant of multistage PID controller、、 ；

(5) the magnitude margin index in the full envelope curve of aircraftDecibels is under stable condition,

From?

In,To frequencyThe maximum of separatingAnd minimum of a value，Interval is，

Judgement:

Meet:

If meet, Flight Controller Design completes, if do not meet, then increases the progression of multistage PID controller.

The invention has the beneficial effects as follows: from the concept of phase margin and magnitude margin, by adding multistage PID to controlDevice is determined multistage according to the requirement and the identification Method that meet given phase margin and magnitude margin in full flight envelopeThe parameter of PID controller, designs and meets that the overshoot of full flight envelope is little, low-latitude flying controller stably.

Below in conjunction with embodiment, the present invention is elaborated.

Detailed description of the invention

Under step 1, given differing heights, Mach number, use Linear chirp（For initial frequency,For cut-off frequency,，For the frequency sweep time) or logarithm swept-frequency signal（For initial frequency,For cut-off frequency,, T isThe frequency sweep time) to aircraft excitation, amplitude-frequency and phase-frequency characteristic in the full envelope curve that can directly obtain allowing to fly, form aircraft completeThe model cluster such as primary control surface and flying height in envelope curve, obtains open loop between corresponding aircraft primary control surface and flying heightTransfer function model bunch matrix is:

Wherein,ForSquare formation,For positive integer,For the independent variable of Laplace transformation,For aircraftFlying height,For Mach number,ForSingle mode square formation,ForMultinomial diagonal matrix,ForSingleMould square formation,For multinomial,For positive integer;

Choose

Satisfy condition:

And

Wherein,ForSquare formation,ForSingle mode square formation,ForMultinomial diagonal matrix,For?Row, theColumn element,For?Row, theColumn element,,ForSingle mode square formation,For multinomial,For phase angle mathematic sign;

The controller of aircraft multiloop system is made as:

Wherein,ForSquare formation,ForDiagonal matrix;For?Row, theColumn element,；

Step 2, controller，Design process as follows:

(1) order, the form of embodying is:

Wherein

、

For multinomialFormula,For the variable after laplace transform conventional in transfer function,Be respectively flying height and Mach number,The time delay of pitch channel,For withThe gain changing,For multinomialIn withThe coefficient bunch changing,For multinomialIn withThe coefficient bunch changing;

(2) directly determine that according to the amplitude versus frequency characte in flight envelope the interval definite method of open loop cut-off frequency is:

From?In, obtain open loop cut-off frequencySeparateMaximumAnd minimum of a value, open loop cut-off frequencyInterval is;

In formula,For the variable in frequency characteristic,For imaginary part represents,For angular frequency;

(3), according to the phase-frequency characteristic in flight envelope, calculate maximum phase nargin in envelope curve，

With minimum phase nargin in envelope curve

，

；

Directly determine with the interval corresponding phase margin of cut-off frequency interval and be:；

(4) transfer function of the multistage PID controller of candidate is:

In formula, N is integer, represents the progression of multistage PID controller to be determined,、、 For constant to be determined;

Add after multistage PID controller,

From?

In, obtain open loop cut-offFrequencyThe maximum of separatingAnd minimum of a value, open loop cut-off frequencyInterval is，

Phase margin index in the full envelope curve of aircraftUnder stable condition, add system after multistage PID controllerPhase marginShould meet:

Meet:

Under These parameters and the common constraint of maximum likelihood criterion, according to the maximum likelihood side in system model Structure IdentificationMethod is determined progression N, the constant of multistage PID controller、、 ；

(5) the magnitude margin index in the full envelope curve of aircraftDecibels is under stable condition,

From?

In,To frequencyThe maximum of separatingAnd minimum of a value，Interval is，

Judgement:

Meet:

If meet, Flight Controller Design completes, if do not meet, then increases the progression of multistage PID controller.

Claims (1)

1. an aircraft multiloop model bunch Composite PID controller design method, its feature comprises the following steps:

Amplitude-frequency in the full envelope curve directly being flown by permission by frequency sweep flight test under step 1, given differing heights, Mach numberForm primary control surface in aircraft full envelope curve and the model cluster of flying height with phase-frequency characteristic, and can cross over flight envelopeThe flutter frequency that obtains aircraft, obtains open-loop transfer function model cluster between corresponding aircraft primary control surface and flying heightMatrix is:

Wherein,ForSquare formation,For positive integer,For the independent variable of Laplace transformation,For aircraft flight highDegree,For Mach number,ForSingle mode square formation,ForMultinomial diagonal matrix,ForSingle mode sideBattle array,For multinomial,For positive integer;

Choose

Satisfy condition:

And

Wherein,ForSquare formation,ForSingle mode square formation,ForMultinomial diagonal matrix,For?Row, theColumn element,For?Row, theColumn element,,ForSingle mode square formation,For multinomial,For phase angle mathematic sign;

The controller of aircraft multiloop system is made as:

Wherein,ForSquare formation,ForRightAngular moment battle array;For?Row, theColumn element,；

Step 2, controller，Design process as follows:

(1) order, the form of embodying is:

Wherein

、

For multinomial,ForVariable in transfer function after conventional laplace transform,Be respectively flying height and Mach number,To bowFace upward the time delay in loop,For withThe gain changing,For multinomialIn withThe coefficient bunch changing,For multinomialIn withThe coefficient bunch changing;

(2) directly determine that according to the amplitude versus frequency characte in flight envelope the interval definite method of open loop cut-off frequency is:

From?In, obtain open loop cut-off frequencySeparateLarge valueAnd minimum of a value, open loop cut-off frequencyInterval is;

In formula,For the variable in frequency characteristic,For imaginary part represents,For angular frequency;

(3), according to the phase-frequency characteristic in flight envelope, calculate maximum phase nargin in envelope curveIn envelope curveMinimum phase nargin

Directly determine with the interval corresponding phase margin of cut-off frequency interval and be:；

(4) transfer function of the multistage PID controller of candidate is:

In formula, N is integer, represents the progression of multistage PID controller to be determined,、、 ForConstant to be determined;

Add after multistage PID controller,

From?In, obtain open loop cut-off frequencyThe maximum of separatingAnd minimum of a value, open loop cut-off frequencyInterval is，

Phase margin index in the full envelope curve of aircraftUnder stable condition, add the phase place of system after multistage PID controllerNarginShould meet:

Meet:

Under These parameters and the common constraint of maximum likelihood criterion, true according to the maximum likelihood method in system model Structure IdentificationProgression N, the constant of fixed multistage PID controller、、 ；

(5) the magnitude margin index in the full envelope curve of aircraftDecibels is under stable condition,

From?

In, obtain frequentlyRateThe maximum of separatingAnd minimum of a value，Interval is，

Judgement:

Meet:

If meet, Flight Controller Design completes, if do not meet, then increases the progression of multistage PID controller.