Power flow control and N-1 contingency analysis with DSRs in unbalanced transmission networks

Abstract

The need for modern electricity infrastructures and more capable grid components brings attention to Distributed Series Reactor (DSR) technology because of its control capabilities. DSRs are a new smart grid technology that can be applied to control flows in transmission or distribution systems. Design of DSRs to control power flow over transmission lines to alleviate overloads due to load growth under single line contingencies is investigated in this paper. N-1 contingency analysis is performed to assure secure operation of the grid while controlling the active power flow. The IEEE 39 bus standard model is modified to a 3-phase, unbalanced transmission model with 345 kV lines that accounts for tower geometry. The design of DSRs to control power flow under N-1 line contingency is performed using this modified 3-phase, unbalanced model. DSR design to control the power flow of a real power system over tie lines connecting different power pool areas and to control the power flow over transmission lines within the area itself is investigated. The economics of DSRs are then evaluated by comparing the DSR design with a design that uses new line construction.

Load growth and power flow control with DSRs: Balanced vs unbalanced transmission networks

“…In the work here, the DSR adds reactance to the self-impedance of the line model. The value of the reactance added depends on the number of DSR modules activated and the selected reactance for each DSR module [16]- [17], [24]. In this study the DSR modules inject 50µH/module (0.01885 ohms).…”

“…Controlling power flow over lines to enhance system capacity, alleviate overloads, and improve reliability has also been addressed in [7]- [17]. Reference [7] proposes a multi-agent system for coordinated and adaptive control of power flow over transmission lines to relieve overloads.…”

“…Design of DSRs to control power flow over transmission lines to alleviate overloads due to load growth under single line contingencies is investigated in [17]. N-1 contingency analysis is performed to assure secure operation of the grid while controlling the active power flow.…”

“…No previous papers in the literature other than the work in [16] and [17] studied the application of DSRs in unbalanced three phase transmission systems, and many of the transmission lines in the US are unbalanced [18][19][20][21]. This work is devoted to investigating the application of DSRs in unbalanced transmission for load growth.…”

Enhanced Contingency Analysis—A Power System Operator Tool

“…The proposed approach addresses both static and dynamic security assessment. In [24] the researchers performed the N-1 contingency analysis with distributed series reactors designed to control power flow in unbalanced transmission networks.…”