Vol.8, No 1, 2009 pp. 13 - 24
UDC 621.313 62-83 621.396.965.8
SPEED-CONTROLLED ELECTRICAL DRIVE WITH NOVEL DISTURBANCE OBSERVER
Djordje Stojić1, Milić Stojić2
1Electrotechnical Institute "Nikola Tesla", Koste Glavinića 8a, 11000 Belgrade, Serbia, E-mail: djoles@sbb.rs
2University of Belgrade, Faculty of Electrical Engineering, Bulevar Kralja Aleksandra 73, 11120 Belgrade, Serbia, E-mail: estojic@etf.rs
Abstract. This paper presents the design of a digitally-controlled speed electrical drive in the presence of arbitrary external immeasurable load disturbances. The extraction of a known class of external disturbances is achieved by using the novel DOB (Disturbance Observer), in which the discrete-time model of external disturbance is included implicitly. It is shown, analytically, by simulation, and experimentally, that the proposed modification of disturbance observer enables the entire rejection of a known class of immeasurable external disturbances, in the steady-state, regardless of the DOB filter cutoff frequency. Thus the speed of disturbance extraction and quality of closed-loop system set-point transient response can be achieved independently. The proposed design procedure is carried out by the speed-controlled drive with a vector-controlled induction motor. Both the simulation and experimental results illustrate the effectiveness and robustness of the proposed technique.
Key Words: Disturbance observer, external load torque disturbance, disturbance model, speed-controlled electrical drive.
BRZINSKI-REGULISANI ELEKTROMOTORNI POGON SA NOVIM OPSERVEROM POREMEĆAJA
Ovaj rad predstavlja projektovanje digitalno-regulisanog brzinskog elektromotornog pogona u prisustvu proizvoljnih spoljnih nemerljivih poremećaja koji nastoje da odvuku sistem iz tekuće radne tačke. Ekstrakcija poznate klase spoljnih poremećaja se izvodi upotrebom novog opservatora poremećaja (DOB), u koji je implicitno uključen vremenski diskretan model spoljnih poremećaja. Pokazano je, analitički, simulacijom, i eksperimentalno, da predložena modifikacija opservera poremećaja omogućava celokupno odbijanje poznate klase nemerljivih spoljnih poremećaja, u ustaljenom stanju, bez obzira na graničnu frekvenciju DOB filtera. Na taj način je moguće dostići zasebno brzinu ekstrakcije poremećaja i kvalitet odziva sistema sa povratnom spregom. Predloženi postupak projektovanja obavlja se brzinski-regulisanim elektromotornim pogonom sa vektorski-upravljanim indukcionim motorom. Efikasnost i robusnost predložene tehnike potvrđuju kako simulacija tako i rezultati eksperimenta.
Ključne reči: Opserver poremećaja, spoljni poremećaji momenta opterećenja, model poremećaja, brzinski-regulisan elektromotorni pogon