CN107422640B - Combined integral system identification method based on relay feedback - Google Patents
Combined integral system identification method based on relay feedback Download PDFInfo
- Publication number
- CN107422640B CN107422640B CN201710649291.0A CN201710649291A CN107422640B CN 107422640 B CN107422640 B CN 107422640B CN 201710649291 A CN201710649291 A CN 201710649291A CN 107422640 B CN107422640 B CN 107422640B
- Authority
- CN
- China
- Prior art keywords
- combined integral
- relay
- formula
- representing
- gain
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B13/00—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion
- G05B13/02—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric
- G05B13/04—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators
- G05B13/042—Adaptive control systems, i.e. systems automatically adjusting themselves to have a performance which is optimum according to some preassigned criterion electric involving the use of models or simulators in which a parameter or coefficient is automatically adjusted to optimise the performance
Landscapes
- Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Artificial Intelligence (AREA)
- Computer Vision & Pattern Recognition (AREA)
- Evolutionary Computation (AREA)
- Medical Informatics (AREA)
- Software Systems (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
- Feedback Control In General (AREA)
Abstract
The invention relates to an application method of a relay feedback identification method on a combined integral system, which is characterized by comprising the following steps: step 1, performing a relay feedback test on a combined integral system to be identified by using an ideal non-biased relay; and 2, utilizing the deviation between the actual oscillation frequency and the theoretical critical oscillation frequency compensated by the offset phase angle to establish a frequency domain information relation, and deducing to obtain system parameters. The invention adopts the parameter identification of the combined integral system based on the relay feedback, can realize single identification to obtain a plurality of parameters, and has high identification precision. Compared with an ATV method or a parameter estimation method for describing a combined integral system by an approximate model, the obtained identification effect is obviously improved.
Description
Technical Field
The invention relates to a method for identifying system parameters and setting controller parameters of a combined integration system by using a relay technology, belonging to the field of industrial process control.
Background
In industrial processes, most objects are generally approximated as first-order and second-order plus pure hysteresis models, and a combined integral system, which is a novel process industrial system proposed in recent years, is approximated as the two process objects for a long time in the past. Although this approximate description addresses the necessity of system control, there is great room for improvement in the control effect. Industrial process devices in the process industry are in an uninterrupted operation state for a long time, and the change of the structure aging operation environment of industrial equipment enables system parameters to drift, so that the control effect of the system is deteriorated, and the situation is serious and shutdown debugging can be faced. Resulting in a reduction in industrial process productivity while reducing resource utilization. In order to solve the control limitation, the system parameter change is responded, and the control effect is improved. Parameter identification and tuning research of a controller for a combined integral system are necessary.
For the combined integral system, the model approximates the deficiencies described:
(1) the first-order and second-order plus pure hysteresis system approximately describes that the combined integral system can only track the Navier curve of the system in a partial frequency domain range of the system, and certain deviation exists;
(2) the controller obtained according to the model design of the approximate description combined integral system cannot achieve ideal effects on control effects, namely rapidity, stability and robustness;
(3) according to the approximate description model, the identification parameters obtained by using a general parameter identification method have large errors, and the accuracy of the description system is further reduced.
Disclosure of Invention
The purpose of the invention is: the accuracy of the description system is improved.
In order to achieve the above object, the present invention provides an application method of a relay feedback identification method in a combined integral system, which is characterized by comprising the following steps:
in the formula, kiRepresenting system gain, s-table complex frequency domain operator, Gi(s) represents a stable polynomial without integral element, τ1iRepresenting a system time-lag parameter, τ2iRepresenting a system time lag parameter.
Step 2, utilizing deviation between the actual oscillation frequency and the theoretical critical oscillation frequency compensated by the offset phase angle to establish a frequency domain information relation, and deducing to obtain system parameters:
(a) the ideal non-biased relay receives the feedback signal to realize the switch switching, and the output of the system presents the frequency omega near the working point under the condition of satisfying the establishment limit switchingoscIs oscillated with a period of ToscAnd y (t) is a controlled object output signal, comprising:
in the formula, Fsn、FcnIf all the values are non-zero constants, phase angle shift exists between the oscillation point and the critical point on the open-loop Nyquist curve of the system, and:
in the formula (I), the compound is shown in the specification,pna phase angle representing the nth harmonic;
(b) for the second-order combined integral object, a new system frequency domain relation is established through offset angle compensation, and the relation is expressed as follows:
in the formula (1), k represents a system gain, ωsDenotes a frequency parameter, T denotes a time constant, k1The gain of the system is represented by,τ2representing a system time lag;
from the amplitude relationships of equations (1), (2), and (3), we can obtain:
from the phase angle relationship:
k1、k3、k5derived from the frequency response of the object being estimated by numerical calculation, i.e.
In equation (8), K is 1,2,3, h denotes a relay output level, and y (i) denotes a system output signal;
the joint type (4) - (8) is calculated by using a 1stopst optimization tool box to obtain system parameters, namely k, tau1,τ2,T。
Due to the adoption of the technical scheme, compared with the prior art, the invention has the following advantages and positive effects:
the invention adopts the system input signal level as the selection principle for determining the switching level of an ideal relay, the relay switch level is set to be five to ten percent of the input level, and the switch is switched in the identification process, so that the system has a limit ring. And establishing a new frequency domain relation, and deducing to obtain the parameters of the combined integral system. Based on the reasons, the system performance analysis method specially aiming at the combined integration process and the application of the combined integration link in other fields have important theoretical and practical significance.
The invention adopts the parameter identification of the combined integral system based on the relay feedback, can realize single identification to obtain a plurality of parameters, and has high identification precision. Compared with an ATV method or a parameter estimation method for describing a combined integral system by an approximate model, the obtained identification effect is obviously improved.
Drawings
FIG. 1 is a basic schematic diagram of a relay feedback;
FIG. 2 is a diagram illustrating function analysis;
FIG. 3 is a waveform of an oscillation output of the combined integration system;
FIGS. 4(a) and 4(b) are comparisons of estimated model Nyquist curves;
FIGS. 5(a) and 5(b) are comparisons of pad approximation, estimated model Nyquist curves;
FIG. 6 is a step response curve for a second order combined integral system;
fig. 7 is a nominal system response curve.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It is to be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention, and that various changes and modifications may be suggested to one skilled in the art upon reading the teachings herein, and that such equivalents are within the scope of the appended claims.
The invention provides an application method of a relay feedback identification method on a combined integral system, which is characterized by comprising the following steps:
in the formula, kiRepresenting system gain, s represents complex frequency domain operator, Gi(s) represents a stable polynomial without integral element, τ1iRepresenting a system time-lag parameter, τ2iA parameter representing the time lag of the system,
without loss of generality, there are typically one to five combined integral objects, the transfer functions i.e. (i) one (v)
Where k denotes the system gain, k1Denotes the system gain, k2Denotes the system gain, T denotes the time constant, τ denotes the system time lag parameter, τ1Representing a system time-lag parameter, τ2Representing a system time-lag parameter, τ3Representing a system time-lag parameter, τ4Representing a system time-lag parameter, τ4=τ1+τ2And s denotes a complex frequency domain operator.
Step 2, utilizing deviation between the actual oscillation frequency and the theoretical critical oscillation frequency compensated by the offset phase angle to establish a frequency domain information relation, and deducing to obtain system parameters:
(a) the ideal non-biased relay receives the feedback signal to realize the switch switching, and the output of the system presents the frequency omega near the working point under the condition of satisfying the establishment limit switchingoscIs oscillated with a period of ToscAnd y (t) is a controlled object output signal, comprising:
in the formula, Fsn、FcnIf all the values are non-zero constants, phase angle shift exists between the oscillation point and the critical point on the open-loop Nyquist curve of the system, and:
in the formula (I), the compound is shown in the specification,pna phase angle representing the nth harmonic;
the characteristics of the combined integral system are different from the characteristics of a first-order or second-order plus pure hysteresis system, and the oscillation waveform output shows the characteristic difference of the first-order or second-order plus pure hysteresis system under the condition that a limit loop is established, as shown in figure 3. The second combined integration system, i.e. (ii), exhibits a typical combined integration characteristic, with an oscillatory output of a trapezoidal wave. The situation that when the combined integral system is approximately described by a first-order or second-order plus lag model, estimated parameters are difficult to solve by using a phase angle shift identification method is explained.
(b) A second order combined integral object (iv) having a frequency characteristic of:
for the second-order combined integral object, a new system frequency domain relation is established through offset angle compensation, and the relation is expressed as follows:
in the formula (1), k represents a system gain, ωsDenotes a frequency parameter, T denotes a time constant, k1The gain of the system is represented by,τ2representing a system time lag parameter;
from the amplitude relationships of equations (1), (2), and (3), we can obtain:
from the phase angle relationship:
k1、k3、k5derived from the frequency response of the object being estimated by numerical calculation, i.e.
In equation (8), K is 1,2,3, h denotes a relay output level, and y (t) denotes a system output signal;
the joint type (4) - (8) is calculated by using a 1stopst optimization tool box to obtain system parameters, namely k, tau1,τ2,T。
In order to verify the effectiveness of the algorithm, a plurality of groups of different combined integral object model tests are selected for comparison. Assuming that the ATV prior information is known, the parameter identification result for the second combined integral object is shown in table 1, and is known from the Nyquist curve comparison of fig. 4(a) and fig. 4 (b): the phase angle shift method is used for identifying that the obtained system model is almost coincident with the actual system, and the identification result of the ATV method has certain deviation.
For the fourth combined integral object, the pad approximation model is directly used to compare with the actual object, and the parameter identification result is shown in table 2. From a comparison of the Nyquist curves of fig. 5(a) and 5(b), it can be seen that: the model obtained by phase angle shift method identification almost coincides with the actual system, and the effect is better than that of a Pade approximate model.
TABLE 1 comparison of identification results for a second combined integration object
TABLE 2 comparison of recognition results for fourth combined integration objects
Since the combined integral object has good open-loop characteristics, the system can respond quickly to reach a given value when a step is given. The step response curve of the second order combined integral system is shown in fig. 6. In order to make the whole closed loop system have good characteristics as shown in fig. 6, the desired closed loop transfer function is selected to have the following structural form:
in the formula, τ10Representing a system time-lag parameter, τ20Representing a system time lag parameter. When lambda is 1, the response time of the open loop is the same as that of the closed loop; when lambda is larger than 1, the response time of the open loop is faster than that of the closed loop; when λ < 1, the response time of the open loop is slower than that of the closed loop. This may reverse the controller transfer function:
let λ be 1, τ10=τ1,τ20=τ2,k0K, there are:
the input and output relations of the controller in the time domain are as follows:
where u(s) represents the controller output. Part of the equation is a proportional term, and the second term can be interpreted as the controller being at [ t- (τ)10+τ20),i-τ20]The output of the time is obtained by predicting the output of the controller at the past time.
And (4) considering 1 second-order combined integral object, and performing simulation comparison by utilizing IMC-PID, predicted PI, PID and a combined integral controller.
According to the identified parameters, the transfer function of the system is known as follows:
compared with a step response curve under the condition of step interference, the control algorithm obtains the step response curve, and as can be seen from fig. 7, the combined integral controller is excellent in rapidity and almost free of overshoot, while IMC-PID and PID have certain overshoot more or less, and the adjusting time is longer. The predicted PI, although not overshooting, is somewhat slower. Overall, the control effect of the combined integral controller is fast and smooth.
The invention applies the concept of phase angle deviation to the relay feedback identification of the combined integral system, and avoids the problem that the estimated parameters cannot be obtained by describing the combined integral system by a first-order or second-order plus pure hysteresis model to carry out parameter identification. And the phase angle deviation is utilized to compensate the deviation between the experimental oscillation point of the relay and the theoretical critical value, so that the approximate error is eliminated. Under the condition of not needing prior information, a plurality of parameters of the combined integral system can be identified and obtained, and a combined integral generator is designed and obtained on the basis, and the control effect is fast and stable.
Claims (1)
1. A combined integral system identification method based on relay feedback is characterized by comprising the following steps:
step 1, performing a relay feedback test on a combined integral system to be identified by using an ideal non-biased relay, wherein the combined integral system is an open-loop stable object, and a transfer function of the combined integral system consists of 2 or more time-lag objects and is expressed in the following form:
in the formula, kiRepresenting system gain, s represents complex frequency domain operator, Gi(s) represents a stable polynomial without integral element, τ1iRepresenting a system time-lag parameter, τ2iRepresenting a system time lag parameter, i represents an ith harmonic, and n represents a harmonic order;
step 2, utilizing deviation between the actual oscillation frequency and the theoretical critical oscillation frequency compensated by the offset phase angle to establish a frequency domain information relation, and deducing to obtain system parameters:
(a) the ideal non-biased relay receives the feedback signal to realize the switch switching, and the output of the system presents the frequency omega near the working point under the condition of meeting the establishment of limit switchingoscIs oscillated with a period of ToscAnd y (t) is a controlled object output signal, comprising:
in the formula, Fsn、FcnIf all the values are non-zero constants, phase angle shift exists between the oscillation point and the critical point on the open-loop Nyquist curve of the system, and:
in the formula (I), the compound is shown in the specification,pna phase angle representing the nth harmonic;
(b) for the second-order combined integral object, a new system frequency domain relation is established through offset angle compensation, and the relation is expressed as follows:
in the formula (1), k represents a system gain, ωsDenotes a frequency parameter, T denotes a time constant, k1The gain of the system is represented by,τ2representing a system time lag parameter;
from the amplitude relationships of equations (1), (2), and (3), we can obtain:
from the phase angle relationship:
k1、k3、k5derived from the frequency response of the object being estimated by numerical calculation, i.e.
In equation (8), K is 1,2,3, h denotes a relay output level, and y (t) denotes a system output;
the joint type (4) - (8) is calculated by using a 1stopst optimization tool box to obtain system parameters, namely k, tau1,τ2,T。
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201710649291.0A CN107422640B (en) | 2017-08-01 | 2017-08-01 | Combined integral system identification method based on relay feedback |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201710649291.0A CN107422640B (en) | 2017-08-01 | 2017-08-01 | Combined integral system identification method based on relay feedback |
Publications (2)
Publication Number | Publication Date |
---|---|
CN107422640A CN107422640A (en) | 2017-12-01 |
CN107422640B true CN107422640B (en) | 2020-08-11 |
Family
ID=60437129
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201710649291.0A Active CN107422640B (en) | 2017-08-01 | 2017-08-01 | Combined integral system identification method based on relay feedback |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN107422640B (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111522224A (en) * | 2020-05-09 | 2020-08-11 | 东华大学 | Parameter self-tuning PLC control method based on prediction PI and bias relay feedback |
CN111897204A (en) * | 2020-06-29 | 2020-11-06 | 华东理工大学 | PID parameter setting method of cascade control system based on single relay feedback |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2004274623A (en) * | 2003-03-11 | 2004-09-30 | Sharp Corp | Data rounding correction circuit and video equipment |
EP2161853A3 (en) * | 2008-09-09 | 2013-06-05 | NTT DoCoMo, Inc. | Radio relay apparatus and method |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7599752B2 (en) * | 2005-05-17 | 2009-10-06 | Utah State University | Tuning methods for fractional-order controllers |
KR100846554B1 (en) * | 2006-11-15 | 2008-07-15 | 경북대학교 산학협력단 | Integrals of relay feedback responses for extracting process information |
US8255066B2 (en) * | 2009-05-18 | 2012-08-28 | Imb Controls Inc. | Method and apparatus for tuning a PID controller |
CN101807878B (en) * | 2010-03-25 | 2011-07-27 | 上海交通大学 | Servo system control method based on relay feedback |
CN103269110A (en) * | 2013-06-09 | 2013-08-28 | 哈尔滨工业大学 | Control parameter self-tuning lithium battery charging control method based on relay feedback |
CN103699010B (en) * | 2013-12-04 | 2016-03-09 | 上海交通大学 | A kind of servo system identification method based on relay position feedback temporal signatures |
CN103941580A (en) * | 2014-04-08 | 2014-07-23 | 上海理工大学 | Closed loop frequency domain identification method of generator set based on bias relay feedback |
CN104950679A (en) * | 2015-06-17 | 2015-09-30 | 上海建坤信息技术有限责任公司 | Air conditioning system model identification method based on bias relay feedback |
CN105674935A (en) * | 2016-02-25 | 2016-06-15 | 上海交通大学 | Relay-feedback-based servo system gap identification method |
CN105759607B (en) * | 2016-02-26 | 2018-08-14 | 北京工业大学 | The design method of PAC controllers based on intelligent control algorithm |
-
2017
- 2017-08-01 CN CN201710649291.0A patent/CN107422640B/en active Active
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2004274623A (en) * | 2003-03-11 | 2004-09-30 | Sharp Corp | Data rounding correction circuit and video equipment |
EP2161853A3 (en) * | 2008-09-09 | 2013-06-05 | NTT DoCoMo, Inc. | Radio relay apparatus and method |
Also Published As
Publication number | Publication date |
---|---|
CN107422640A (en) | 2017-12-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Zhang et al. | Low-complexity tracking control of strict-feedback systems with unknown control directions | |
Gao | Scaling and bandwidth-parameterization based controller tuning | |
CN108303885B (en) | Self-adaptive control method of motor position servo system based on disturbance observer | |
Huang et al. | Adaptive sliding control for single-link flexible-joint robot with mismatched uncertainties | |
Joseph et al. | Cohen-coon PID tuning method; A better option to Ziegler Nichols-PID tuning method | |
Deng et al. | Adaptive integral robust control and application to electromechanical servo systems | |
CN107422640B (en) | Combined integral system identification method based on relay feedback | |
Ryu et al. | Auto-tuning of sliding mode control parameters using fuzzy logic | |
CN109361333B (en) | Online inertia identification method and system, motor controller and readable memory | |
Berger et al. | Time optimal trajectory planning with feedforward and friction compensation | |
Raza et al. | Feedback linearization using high gain observer for nonlinear electromechanical actuator | |
Patelski et al. | Tracking control for a cascade perturbed control system using the active disturbance rejection paradigm | |
Su et al. | On performance limitation in tracking a sinusoid | |
Chen et al. | Motion control with deadzone estimation and compensation using GRNN for TWUSM drive system | |
Liu et al. | Hybrid reference governor-based adaptive robust control of a linear motor driven system | |
Kim et al. | Ga-based practical auto-tuning technique for industrial robot controller with system identification | |
CN110048600B (en) | Method for carrying out second-order sliding mode synchronous optimization on time lag value delta and switching frequency in DC-DC buck converter | |
Al Janaideh et al. | Adaptive control of uncertain Hammerstein systems with hysteretic nonlinearities | |
Davoodi et al. | Design and implementation of a feedforward feedback controller for a piezoelectric actuator | |
Herrera et al. | Identification and adaptive control of delayed unstable systems | |
Nguyen et al. | Robust precision positioning control on linear ultrasonic motor | |
Zheng et al. | Modified Smith predictor for frequency identification and disturbance rejection of single sinusoidal signal | |
Antritter et al. | Nonlinear tracking control of a dc motor via a boost-converter using linear dynamic output feedback | |
Osypiuk | Simple robust control structures based on the model‐following concept–A theoretical analysis | |
Zhao et al. | Self-optimizing Control of an Air Source Heat Pump |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |