This paper with an open-loop V/f control mode of inverter supply, searched for the causes of the oscillation using small signal analysis on the axially-laminated anisotropic (ALA) rotor and hybrid rotor (ALA-SPM two-part) motor, and analyzed operating performance of the motors with inertial damper on the same shaft. Results show that the negative electromagnet damping coefficient can be the key point to result in the oscillation; the electromagnet damping coefficient can increase with the increasing new variable k, the fraction length of SPM part, the maximum load of the motors and the stability can be improved. The stability of the system and the dynamic performance can be better with reasonable viscous damping coefficient of inertial damper, the motors can adequately develop their output torque capability, and improve operating performance. Ill. 11, bibl. 11, tabl. 3 (in English; abstracts in English and Lithuanian).Xuezhen Chen, Chenglin Gu. Hibridinio rotorinio variklio darbo našumo tyrimas // Elektronika ir elektrotechnika. -Kaunas: Technologija, 2011. -Nr. 7(113). -P. 3-8.Analizuojami mažų signalų hibridinio rotorinio variklio,veikiančio atviro ciklo V/f valdymo režimu, virpesiai, tiriamas to paties veleno su inerciniu slopintuvu variklių darbo našumas. Nustatyta, kad neigiamas elektromagnetinis slopinimo koeficientas daugiausia įtakos turi signalo virpesiams. Elektromagnetinis slopinimo koeficientas didėja didėjant naujam kintamam dydžiui k, keičiantis SPM dalies ilgiui. Naudojant inercinio slopintuvo klampiojo slopinimo koeficientą, galima padidinti sistemos stabilumą ir dinaminį našumą. Il. 11, bibl. 11, lent. 3 (anglų kalba; santraukos anglų ir lietuvių k.).