Elektromanyetik Yataklı Rotorların MIMO PID Kontrolu

Elektromanyetik yataklı rotorlar kararsız sistemler oldukları için geribeslemeli kontrol çalışma şartlarının ayrılmaz bir parçasıdır. Rotor dinamiği sabit hızda doğrusal ve zamanla değişmeyen özellikte olmakla birlikte, elektromanyetik yatak dinamiği doğrusal değildir. Doğrusal olmayan yatak dinamiği sabit bir sapma akımı kullanılarak bir çalışma noktası civarında doğrusallaştırılabilir. Bu makalede yatay rotor/aktif manyetik yataklı sistemler için MIMO PID kontrolör tasarlayarak SISO PID kontrol ile performansını karşılaştırmaktayız. Rotor dinamiğindeki dinamik eşleşme birbirine dik yönlerde jiroskopik kuvvetler oluşturmaktadır. Eşleşik (dinamik) dengesizlik kuvvetler nedeniyle oluşabilecek yanal yönlerdeki açısal hareketlerin meydana getirdiği jiroskopik kuvvetlerin kompanzasyonu için SISO PID kontrol yeterli performansa sahip değildir.

Anahtar Kelimeler:

Konveks optimizasyon, MIMO PID kontrol, dinamik balanssızlık giderme, jiroskopik rotor dinamiği, elektromanyetik yataklar

MIMO PID Control of Rotors with Electromagnetic Bearings

Rotors with electromagnetic bearings are inherently unstable systems; hence feedback control is an integral part of their operation. While the rotor dynamics is linear and time-invariant at constant operation speed, electromagnetic bearing model is non-linear. Non-linear bearing dynamics can be linearized at an operating point using a constant bias current. In this paper we design a MIMO PID controller for horizontal rotor/active magnetic bearing systems and compare its performance with respect to SISO decentralized PID control. Dynamic coupling in rotor dynamics causes gyroscopic forces to act at orthogonal directions on the rotor. SISO PID control lacks sufficient performance as it has limited capability to compensate for the gyroscopic effects due to angular motions in transverse directions which can be caused by couple (dynamic) unbalance forces.

Keywords:

Konveks optimizasyon, MIMO PID kontrol, dinamik balanssızlık giderme, jiroskopik rotor dinamiği, elektromanyetik yataklar,

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