New microprocessor based relay to monitor and protect power systems against sub-harmonics

Multi-parameter bifurcation analysis of subsynchronous interactions in DFIG-based wind farms

“…SSO also appeared in a 150 MVA DFIG wind farm located in Minnesota, USA. In this case, the triggering condition was similar to the one experienced in Texas, i.e., after a fault on the system the wind farm became radially connected with a corridor with 60% of series compensation [22]. Another incident was reported in the north of China, where a 3000 MVA wind generation (composed mostly of DFIG turbines) experienced very low-frequency oscillations [23,24].…”

Evaluation of Phase Imbalance Compensation for Mitigating DFIG-Series Capacitor Interaction

“…An overview of reported DFIG-SSR events is given in Table I. 6.3 Hz Minnesota, USA -2011 [7] 9 -13 Hz Hebei, China -2012 [8] 6 -8 Hz Hebei, China -2013 [9] 8.1 Hz Texas, USA -2017 [10] 25.6 Hz Texas, USA -2017 [10] 22.5 Hz Texas, USA -2017 [10] 26.5 Hz…”

“…STATCOM [13]) and protection relays to trip either the wind farm or the series capacitor (e.g. [7]).…”

Sub-synchronous interaction analysis between DFIG based wind farm and series compensated network

“…leading to excessive currents both at the wind turbine level and the point of common coupling (PCC), and creating significant over-voltages at the utility level before relays detect [1]. Such events have been reported in the Electric Reliability Council of Texas (ERCOT) system and other places [3]- [4].…”