Georgia Power

About: Georgia Power is a company organization based out in Atlanta, Georgia, United States. It is known for research contribution in the topics: Voltage & Power-system protection. The organization has 73 authors who have published 66 publications receiving 932 citations. The organization is also known as: Georgia Railway and Power Company.

A Comparison of 100 Percent Stator Ground Fault Protection Schemes for Generator Stator Windings

Abstract: This paper describes three different schemes for detecting single-phase-to-ground faults in 100% of the generator stator winding. The operating theory, a setting example, and field measurements are provided for each of the three schemes. A chart comparing the significant application characteristics of the three schemes is presented.

Transmission level instrument transformers and transient event recorders characterization for harmonic measurements

Abstract: A technique for laboratory characterization of instrument transformers designed for transmission level voltage and current measurements is presented. The technique is also extended to transient event recorders (TERs). The objective of the method is to determine the suitability of existing substation instrument transformers for harmonic measurements, particularly in the frequency range of 60 to 1500 Hz covering the first 25 harmonics. Specifically, the following characteristics are of interest: transfer function magnitude and phase, linearity, and sensitivity of the frequency response to burdens. The measurement technique is based on exciting the instrument transformer primary with an impulsive waveform. Both input and output waveforms are recorded using laboratory grade probes and digitizers. Digital signal processing techniques are used to compute the instrument transformer frequency response. Several voltage transformers and current transformers in the 230 kV-765 kV voltage range were tested. The results are described. >

Slope-Permissive Under-Voltage Load Shed Relay for Delayed Voltage Recovery Mitigation

Abstract: In this paper, a new relay algorithm is proposed for under-voltage load shedding (UVLS) based on rate of voltage recovery and predicted time to recover above a preset voltage threshold Simulation experience in the Southern Electric System has shown that conventional UVLS relay logic is ill-suited to the task of mitigating delayed voltage recovery and fast voltage collapse situations while maintaining compliance with existing NERC Reliability Standards The proposed scheme continuously monitors both voltage magnitude and rate-of-change of voltage magnitude and uses these values to determine a projected voltage recovery time following a contingency event If the projected recovery time is such that resultant system conditions are unacceptable (eg, major load loss, loss of generation, or voltage collapse), the relay will operate to shed load at the distribution feeder level This unique scheme has been implemented in a commercially-available programmable relay and is presently installed and active in a number of substations in Georgia Power Company

Coordination of Load Conservation with Turbine-Generator Underfrequency Protection

Abstract: A system disturbance or operating abnormality may leave a power system with a generation deficiency, which, if uncorrected, can result in an extensive power outage. The possibility of such disturbances has led to increased interest in the application of automatic underfrequency protection schemes to restore load/generation balance and to prevent equipment damage. This paper presents a comprehensive underfrequency protection program recently developed for the Southern electric system in which digital computer simulations were used to optimize a system- wide load shed program and to verify its coordination with a steam turbine-generator underfrequency protection scheme.