Influence of generator excitation system on generator under-impedance protection

Investigation of STATCOM effects on synchronous generator impedance based LOF relay with considering a realistic model for the excitation system of the generator

This paper studies the effects of static synchronous compensator (STATCOM) on synchronous generator conventional loss of field (LOF) protection. To accomplish a comprehensive study, a typical and realistic excitation system is considered for the generator by using the phase-domain generator model available in the real-time-digital-simulator. Using such a system, LOF phenomenon is realistically ...

The Influence of Impedance Values and Excitation System Tuning on Synchronous Generator Stability in Distribution Grids

Synchronous machines installed in recently developed small-scale hydro power plants in Norway have relatively high values of the synchronous reactances, as well as the sub-transient and transient reactances. Typical synchronous reactance is 2 – 2.5 pu, but values up to 3.1 pu are experienced, which is 3 times the typical values for larger low-speed synchronous generators (with salient poles). H...

Impedance-Based Out-of-Step Protection of Generator in the Presence of STATCOM

This paper presents a novel impedance-based approach for out-of-step (OOS) protection of a synchronous generator. The most popular and commonly used approaches for detecting OOS conditions are based on the measurement of positive sequence impedance at relay location. However, FACTS devices change the measured impedance value and thus disrupt the performance of impedance-based relay function. In...

Generator Over Excitation Capability and Excitation System Limiters

Sometimes, power system events have shown the need for generators to operate in the overexcited region to support stable operation. Operation up to, and transiently beyond, the overexcited limits from the capability curve is sometimes required. The two main issues in the paper are the generator capability in this region and the design of OEL (OverExcitation Limiters) in the excitation system th...

Dynamic Testing of Generator Protection Using a Model Generator Platform