Nelinearno vodenje laboratorijske naprave polhelikopter

magistrsko delo

Martin Porenta (Avtor), Igor Škrjanc (Mentor), Goran Andonovski (Komentor)

Povzetek

Pri vodenju sistemov se v praksi dostikrat srečamo z nelinearnimi sistemi, za katere je značilno, da izkazujejo precej kompleksnejšo dinamiko kot linearni sistemi. To pomeni, da s klasičnimi regulatorji ne moremo zagotoviti dovolj dobrega delovanja zaprtozančnega vodenja čez celotno delovno območje. Zato smo se v tem magistrskem delu posvetili zaprtozančnemu vodenju nelinearnega dinamičnega sistema z naprednejšimi nelinearnimi regulatorji. Eksperimente smo izvajali na laboratorijski napravi polhelikopter in njenem matematičnem modelu. Napravo sestavlja nihalo, ki je v sredini vrtljivo vpeto. Na levi strani nihala imamo proti utež na desni strani pa elektro motor s propelerjem. Sistem kot vhod prejme napetost na elektromotorju in na izhodu vrne kot odmika. Naprava izkazuje nelinearno delovanje in precej ocsilatoren odziv, zato je še posebej primerna za testiranje razvitih nelinearnih regulatorjev. Cilj magistrske naloge je bil, da smo spoznali različne napredne regulatorje ter poiskati najboljšega za vodenje naprave polhelikopter. Celotno magistrsko delo je razdeljeno na šest glavnih poglavij. V prvem uvodnem poglavju na kratko predstavimo teoretične osnove vodenja sistemov. Ker se bomo v delu srečevali z naprednejšimi nelinearnimi regulatorji, ki temeljijo na nelinearnem modelu sistema, smo v uvodnem poglavju na kratko predstavili teorijo identifikacije nelinearnih modelov sistema. Kot smo že omenili, bomo za vodenje sistema uporabili naprednejše pristope. Zato smo v drugem poglavju podrobneje predstavili teorijo in izpeljali izraze vseh uporabljenih naprednejših regulatorjev. V magistrskem delu smo uporabili tri različne regulatorje: mehki prediktivno funkcijski regulator (FPFC), regulator na osnovi nevronskih mrež NARMA L2 in regulator PID z optimiziranimi parametri. Vse eksperimente smo izvajali na laboratorijski napravi polhelikopter in njenem matematičnem modelu, zato je četrto poglavje magistrske naloge posvečeno analizi statičnih in dinamičnih lastnosti laboratorijske naprave. Izkaže se, da je dobro poznavanje lastnosti sistemi, ki ga vodimo, ključno za uspešno načrtovanje eksperimentov in regulacijskih algoritmov. Vse regulacijske algoritme smo najprej razvili na modelu naprave, saj je zajemanje meritev in identifikacija modela veliko hitrejša in tudi iskanje napak v programski kodi veliko lažje. Nato smo regulatorje razvili še na realnem sistemu in opazovali kakšne spremembe moramo narediti, da nek kompleksnejši regulator uspešno zaživi na realnem sistemu. Po končani analizi laboratorijske naprave in njenega modela v četrtem poglavju predstavimo rezultate vodenja z razvitimi regulatorji. Najprej predstavimo rezultate vodenja za posamezni regulator, ki jih v zadnjem podpoglavju četrtega poglavja primerjamo med seboj, da določimo najboljšo vrsto regulatorja za obravnavani problem. Izkaže se, da najboljše rezultate vodenja dobimo z regulatorjem FPFC, ampak je razvijanje FPFC zamudnejše kot s PID. Regulator PID dobro deluje na začetku delovnega območja (manjši koti odmika naprave polhelikopter), pri večjih odmikih pa postane odziv sistema precej oscilatoren. FPFC izkazuje precej manjše oscilacije kot regulator PID, ampak v ustaljenem stanju slabše odpravlja motnje kot PID. NARMA L2-regulator se precej dobro izkaže pri vodenju na modelu sistema, ampak nam regulatorja ni uspelo usposobiti na realnem sistemu. Pri vodenju NARMA L2-regulatorja na realnem sistemu dobimo nestabilen odziv sistema in nikakor ne uspemo dobiti dobrega delovanja. V petem in šestem poglavju sledita še podrobnejša razprava rezultatov in zaključek magistrskega dela.

Ključne besede

dinamični sistemi;identifikacija;regulacija;prediktivni regulatorji;nevronske mreže;magisteriji;

Podatki

Jezik:	Slovenski jezik
Leto izida:	2022
Tipologija:	2.09 - Magistrsko delo
Organizacija:	UL FE - Fakulteta za elektrotehniko
Založnik:	[M. Porenta]
UDK:	681.5(043.3)
COBISS:	115207427
Št. ogledov:	65
Št. prenosov:	14
Ocena:	0 (0 glasov)
Metapodatki:

Ostali podatki

Sekundarni jezik:	Angleški jezik
Sekundarni naslov:	Nonlinear control of a semi-helicopter laboratory device
Sekundarni povzetek:	When designing control loops, we often encounter non-linear systems that have much more complex dynamics than linear systems. This means that we cannot use classical control algorithms to guarantee that the control loop works sufficiently well over the entire operating range. Therefore, in this master thesis we focus on the control of a nonlinear dynamic system with more advanced nonlinear controllers. All experiments were performed on a semi-helicopter laboratory device. The device consists of a pendulum which is rotatably mounted in the center. On the left side of the pendulum is a counterweight and on the right side is an electric motor with a propeller. The system receives the voltage at the electric motor as input and returns the offset angle as the output. The device shows non-linear operation and a rather oscillating response, so it is particularly suitable for testing developed non-linear controllers. The entire master's thesis is divided into six main chapters. In the first introductory chapter, we briefly present the theoretical foundations of the control of dynamical systems. Since we will encounter more advanced nonlinear controllers based on a nonlinear system model, we briefly introduced the theory of identification of the nonlinear system model. As mentioned earlier, we will use more advanced approaches to control our system. Therefore, in the second chapter we have presented the theory in more detail and derived the expressions of all the advanced controllers used. In the master thesis we have used three different controllers: Fuzzy Predictive Function Controller (FPFC), NARMA L2 Neural Network Controller and PID controller with optimised parameters. All experiments were conducted on a semi-helicopter laboratory device and its mathematical model, so that the fourth chapter of the master's thesis is devoted to the analysis of the static and dynamic properties of the laboratory device. It has been found that a good knowledge of the properties of the system is crucial for the successful design of experiments and control algorithms. We first developed all the control algorithms on the model of the device, as it is much faster to collect measurements and identify the model, and it is also much easier to look for errors in the program code. Then we developed the controls on the real system and observed what changes we had to make to make a more complex control work successfully on the real system. After the analysis of the laboratory device and its model, in the fourth chapter we present the results of control with developed regulators. We first present the results for each controller, which we compare in the last subsection of chapter four to determine the best controller type for our problem. It turns out that the best control results are obtained with an FPFC controller, but the development of the FPFC is more time-consuming than that of a PID controller. The PID controller works well at the beginning of the working range (smaller offset angles of the helicopter), but at higher offsets the system response becomes quite oscillatory. The FPFC has much less oscillation than the PID controller, but at steady state it performs worse than the PID controller at removing disturbances. The NARMA L2 controller works quite well when run on a system model, but we were not able to train the controller on a real system. When we run the NARMA L2 controller on a real system, we get an unstable system response and we never manage to get good performance. Chapters five and six are followed by an even more detailed discussion of the results and the conclusion of the master's thesis.
Sekundarne ključne besede:	dynamic system;identification;closed loop control;predictive control;neural network;
Vrsta dela (COBISS):	Magistrsko delo/naloga
Študijski program:	1000316
Konec prepovedi (OpenAIRE):	1970-01-01
Komentar na gradivo:	Univ. v Ljubljani, Fak. za elektrotehniko
Strani:	XIV, 108 str.
ID:	15899401