IEEE 421.5:1992 pdf download.IEEE Recommended Practice for Excitation System Models for Power System Stability Studies.
When the behavior of synchronous machines is to be simulated accurately in power system stability studies, it is essential that the excitation systems of the synchronous machines be modeled in sufficient detail, see 11211. The desired models must be suitable for representing the actual excitation equipment performance for large, severe disturbances as well as for small perturbations.
A 1968 IEEE Committee Report (see 161) provided initial excitation system reference models. It established a common nomenclature, presented mathematical models for excitation systems then in common use, and defined parameters for those models. A 1981 report (see 171) extended that work. It provided models for newer types of excitation equipment not covered previously as well as improved models for older equipment.
This document, based heavily on the 1981 report, is intended to again update the models, provide models for additional control of features, and formalize those models in a recommended practice. To some extent, the model structures presented in this document are intended to facilitate the use of field test data as a means of obtaining model parameters. The models are, however, reduced order models and do not represent all of the control loops on any particular system. In some cases, the model used may represent a substantial reduction, resulting in large differences between the structure of the model and the physical system.
The excitation system models themselves do not allow for regulator modulation as a function of system frequency, an inherent characteristic of some older excitation systems. The models are valid for frequency deviations of ±5% from rated frequency and oscillation frequencies up to about 3 Hz. These models would not normally be adequate for use in studies of suhsynchronous resonance or other shaft torsional interaction problems. Delayed protective and control functions that may come into play in long term dynamic performance studies are not represented.
A sample set of data (not necessarily typical) for each of the models, for at least one particular application, is provided in Appendix I. A suffix, A, is used with the version of all models described in this report to differentiate them from previous models.
2. References
This standard shall be used in conjunction with the following publications:
[1] ANSI C50. 10-1990, American National Standard for Synchronous Machines — Rotating Electrical Machinery.2
[21 IEEE Std 100-1988, IEEE Standard Dictionary of Electrical and Electronics Terms (ANSI).3
[31 IEEE Std 115-1983, IEEE Test Procedures for Synchronous Machines (ANSI).
[4] IEEE Std 421.1-1986. IEEE Standard Definitions for Excitation Systems for Synchronous Machines (ANSI).
[5] Bayne, J. P., Kundur, P., and Watson, W. 4bStatic Exciter Control to Improve Transient Stability,” IEEE Transactions on Power Apparatus and Systems, vol. PAS—94, pp. 1141—1146, July 1975.
[61 “Computer Representation of Excitation Systems.” IEEE Committee Report, IEEE Transactions on Power Apparatus and Systems, voL PAS-87, no. 6. pp. 1460—1464. June 1968.IEEE 421.5 pdf download.