A Brief Review of Super-excitation Schemes in Short-circuit Generators


V. Sreeram
D. H. Gopal
M. R. Ravindra Mohare


Most short circuit generators have static excitation systems to supply field current to the rotor circuit. All synchronous alternators suffer a reduction in the terminal voltage due to high armature reaction which is a result of the extremely high magnitude short-circuit currents. The reduction in terminal voltage will lead to a corresponding reduction in the stator current magnitude. The short-circuit generators are expected to maintain a constant magnitude of current for specified duration to complete the tests as per corresponding standards. Hence the short-circuit generators invariably make use of super-excitation to maintain the required magnitude of short-circuit currents for specified duration. During circuit breaker testing, it is required to maintain the recovery voltage at pre-fault levels. This requires significant over excitation of the machine. This paper presents a brief review of the methodology and algorithm of super-excitation schemesadopted in short circuit testing along with actual data recorded at the High Power Laboratory at CPRI, Bangalore.


How to Cite
Sreeram, V., Gopal, D. H., & Ravindra Mohare, M. R. (2015). A Brief Review of Super-excitation Schemes in Short-circuit Generators. Power Research - A Journal of CPRI, 45–50. Retrieved from https://cprijournal.in/index.php/pr/article/view/744


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