Assessment of multipulse converter average models for stability studies using a quasistationary small-signal technique

This paper presents a capability assessment of multipulse converters average models to perform stability studies in commercial-aircraft electrical power systems. Particularly, a quasistatic small-signal analysis technique is employed to determine unstable quiescent operating points, which are later verified on the average model by means of small-signal output impedance measurement and transient simulations. The effectiveness of the average model was tested up to its limit, being in effect capable of predicting the subtlest of instabilities, such as the ones that could occur during line commutation. The paper presents a detailed description of the averaging method employed, as well as an in-depth description of the quasistationary small-signal technique used for the stability analyses. Results obtained, namely transient and frequency domain simulations using Synopsys´ Saber/sup R/, validate the theoretical considerations disclosed.