Partition-composition method for online detection of interconnected power system transient stability

This paper presents a novel controller for DFIG based wind parks, designed to achieve more efficient voltage regulation, reactive power compensation and to enhance the transient stability margin of the interconnected power system. The supervisory-secondary voltage control is used to generate the local voltage reference, providing an improved overall voltage profile, while combining an automatic gain controller (AGC) to improve the transient response of the primary control loop. The controller is implemented and tested with a power system comprising of a lumped, fundamental frequency model of a DFIG based wind park, and hydro and diesel generators connected to the electric grid. The performance of the controller was investigated for both steady-state improvements as well as under extreme contingencies to demonstrate its benefits.

Download Full-text

Multi-objective virtual inertia control of renewable power generator for transient stability improvement in interconnected power system

International Journal of Electrical Power & Energy Systems ◽

10.1016/j.ijepes.2019.105641 ◽

2020 ◽

Vol 117 ◽

pp. 105641 ◽

Cited By ~ 1

Author(s):

Xiangyu Zhang ◽

Zhengzhen Zhu ◽

Yuan Fu ◽

Wenqi Shen

Keyword(s):

Power System ◽

Transient Stability ◽

Power Generator ◽

Interconnected Power System ◽

Multi Objective ◽

Renewable Power ◽

Virtual Inertia ◽

Inertia Control

Download Full-text

Fuzzy-Based Torsional Oscillations Mitigation via Thyristor Switched Braking Resistor in Multi-Machine Power System

Advanced Science Engineering and Medicine ◽

10.1166/asem.2020.2653 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1102-1124

Author(s):

M. Fayez ◽

F. Bendary ◽

M. El-Hadidy ◽

M. Mandor

Keyword(s):

Power System ◽

Transmission Lines ◽

High Speed ◽

Transient Stability ◽

Fuzzy Logic Controller ◽

Low Cost ◽

Torsional Oscillation ◽

Turbine Generator ◽

Torsional Oscillations ◽

Interconnected Power System

Turbine generator shaft torsional oscillations is an interdisciplinary power system dynamic problem as it involves mechanical and electrical engineering. Torsional oscillations occur in the mechanical for electrical reasons. Torsional oscillations cause fatigue life expenditure of the mechanical shaft system. There have been great motivations to mitigate the shaft torsional oscillations especially when unrestricted high speed reclosure (HSR) is utilized on the overhead transmission lines emanating from a generation station. Mitigation of torsional oscillation compromises between the use of HSR and preserving the mechanical integrity of the involved turbine generator set. Therefore, braking resistor (BR) controlled by fuzzy logic controller is presented in this paper as a low cost, reliable mean for torsional oscillations mitigation. BR was first utilized for the system transient stability enhancement. It serves as an extra load capable of dissipating extra generated power in case of system severe faults close to a generation station consequently prevents generator pole slipping conditions. IEEE 3 machine 9 bus system is adopted in this paper to test the effects of BR on shaft torsional oscillations mitigation in interconnected power system. Comparative simulation studies between the unsuccessful reclosure with and without fuzzy controlled BR prove the effectiveness of the scheme for mitigation of torsional oscillations significantly.

Download Full-text