PROJECT TITLE :

Power system electromechanical oscillation modes as affected by dynamic interactions from grid-connected PMSGs for wind power generation - 2017

ABSTRACT:

Dynamic interactions between a grid-connected permanent magnet synchronous generator (PMSG) and power system are normally weak. This paper reports a special condition of modal resonance, underneath which the grid-connected PMSG may dynamically interact with power system strongly to have an effect on power system electromechanical oscillation modes (EOMs). The special condition of modal resonance reported during this paper is that an open-loop converter oscillation mode (COM) of PMSG is shut to an open-loop EOM of an influence system on the complex plane. Damping torque analysis is disbursed to elucidate why robust dynamic interactions between PMSG and power system could occur beneath the condition of modal resonance. Results of theoretical analysis in this paper indicate that incidence of modal resonance might possibly cause the damping of either closed-loop COM or EOM to decrease such that power system little-signal angular stability is affected negatively by grid affiliation of PMSG. Responsible COMs for modal resonance are found to be connected with active/reactive power control systems of a grid-aspect converter of PMSG. Within the paper, an example multimachine power system with PMSGs is presented to demonstrate and validate analysis and conclusions made.