Search

Differential protection schemes for busbars, generators or transformers connect multiple current transformers in parallel across a common burden. This paper describes the techniques used to simulate such an arrangement and concentrates particularly on the 3 CT case. Index Terms--B-H loop, hysteresis, current transformers, simulation.

The hysteresis loop of the core material in a test CT is simulated using the Jiles-Atherton theory. Comparisons are made between recorded and simulated waveforms and it is found necessary to replace the modified Langevin function used by Jiles and Atherton. Using an alternative function described in the paper, good agreement is achieved between test and simulated waveforms. Index Terms--B-H loop, current transformers, hysteresis, simulation.

The paper presents a platform system for the incorporation of flexible ac transmission systems (FACTS) devices. The platform permits detailed electromagnetic transients simulation as it is of manageable size. It manifests some of the common problems for which FACTS devices are used such as congestion management, stability improvement, and voltage support. The platform can be valuable for the validation of reduced order models such as small signal or transient stability models. The paper presents details on the development and validation of a small signal based model with the inclusion of a Unified Power Flow Controller. The validated model is then used successfully for the design of a feedback controller for improved damping. [ABSTRACT FROM AUTHOR]

A hysteresis model based on the Jiles--Atherton theory is incorporated into a power transformer model in an electromagnetic transient program (EMTP)-type program. The eddy current effects are also included in the same model. Comparisons are made between recorded and simulated waveforms using a single-phase distribution transformer. A good agreement is achieved between recorded and simulated data. [ABSTRACT FROM AUTHOR]