Aircraft Power System Stability Study Including Effect of Voltage Control and Actuators Dynamic

This paper describes a stability analysis of aircraft ac frequency-wild power systems with constant power loads (CPL). In contrast to previous publications, the proposed analysis method employs the dq modeling approach instead of the state-space averaging (SSA) and average-value modeling (AVM) methods to derive power-electronic converter models for stability studies. This results in lower order models and allows the modeling of vector-controlled converter elements where the SSA and AVM methods are not easily applicable. The resulting model can be combined with models of other power system elements expressed in terms of synchronously rotating frames (generators, front-end converters, vector-controlled drives, etc.). The paper analyzes the stability of frequency-wild power systems for both load and parameter variations and takes into account controlled generator voltage dynamics and electromechanical actuator dynamics. The stability margins are assessed and compared with those for power systems with the ideal voltage source and the ideal CPLs. The study is supported by intensive time domain simulations that support the theory.