eCite Digital Repository

A novel loss-of-excitation protection scheme based on load angle variation of parallel snchronous generators


Rostami, A and Rezaei, N and Jalilian, A and Naderi, B and Negnevitsky, M, A novel loss-of-excitation protection scheme based on load angle variation of parallel snchronous generators, Proceedings of IEEE International Conference on Smart Technologies for Power, Energy and Control, 19-22 December 2021, Bilaspur, Chhattisgarh, India, pp. 1-6. ISBN 9781665443197 (2021) [Refereed Conference Paper]

Pending copyright assessment - Request a copy

DOI: doi:10.1109/STPEC52385.2021.9718655


The main weaknesses of the impedance-based loss of excitation (LOE) relay are its mal-operation during the power system disturbances (PSD) and its long detection time during LOE events. In this paper, to rectify the mentioned problems, a new LOE protection scheme is presented based on the load angle (δ) variation of the parallel synchronous generators (SGs) connected to a point of connection (POC). It will be shown that during a PSD, the variation of δ for all parallel SGs is similar such that their δ increases or decreases simultaneously. However, it will be shown that when the LOE happens in one of the parallel SGs, the δ of faulty SG increases while other SGs will experience reduction in their δ. Hence, when more than one SG is connected to a POC, the LOE condition can be discriminated from PSDs by the proposed LOE relay. However, when one SG is connected to the POC, the conventional impedance-based relay is employed to detect LOE/PSD. Since in real condition, the outage rate of the parallel connected SGs in a power plant is very low on a yearly basis, therefore, the contribution of the conventional impedance relay in detection of LOE/PSD is quite limited to some special instances. Simulation studies on a typical power prove high efficiency of the proposed algorithm.

Item Details

Item Type:Refereed Conference Paper
Keywords:protection, Loss-of-excitation, impedance relay, load angle, parallel synchronous generators
Research Division:Engineering
Research Group:Electrical engineering
Research Field:Electrical energy generation (incl. renewables, excl. photovoltaics)
Objective Division:Energy
Objective Group:Renewable energy
Objective Field:Renewable energy not elsewhere classified
UTAS Author:Naderi, B (Dr Seyedbehzad Naderi)
UTAS Author:Negnevitsky, M (Professor Michael Negnevitsky)
ID Code:155282
Year Published:2021
Deposited By:Engineering
Deposited On:2023-02-08
Last Modified:2023-02-08

Repository Staff Only: item control page