Power system inter-area oscillations can be damped using distributed control of multiple power injections within the interconnection. This type of control traditionally requires system-wide measurements which are transmitted from dispersed, sometimes remote, locations and are subject to delays. This paper evaluates the effect that delayed feedback signals have on the stability of a two-area power system and presents delay-dependent criteria for stability using two different implementations of a damping controller. The controllers are based on a uniform proportional control action and use two feedback signals one from each area of the two-area power system. Each of these signals is subject to an independent delay. Using a Lyapunov-based approach, sufficient conditions for stability that depend on each time delay are found for a range of proportional control gains. Numerical results show that the regions of time delays for which the system is stable are reduced as the proportional gain increases. Time domain simulations validate these stability regions and show the varying responses for the two control implementations and different values of the proportional gain.

10aAA14-0061 aWilches-Bernal, Felipe1 aCopp, David, A.1 aGravagne, Ian1 aSchoenwald, David, A. uhttps://ieeexplore.ieee.org/document/8600640/01749nas a2200157 4500008004100000245009300041210006900134260002900203520120500232653001301437100002701450700002001477700001801497700002601515856005001541 2018 eng d00aStability Criteria for Power Systems with Damping Control and Asymmetric Feedback Delays0 aStability Criteria for Power Systems with Damping Control and As aFargo, NDbIEEEc09/20183 aPower system inter-area oscillations can be damped using distributed control of multiple power injections within the interconnection. This type of control traditionally requires system-wide measurements which are transmitted from dispersed, sometimes remote, locations and are subject to delays. This paper evaluates the effect that delayed feedback signals have on the stability of a two-area power system and presents delay-dependent criteria for stability using two different implementations of a damping controller. The controllers are based on a uniform proportional control action and use two feedback signals one from each area of the two-area power system. Each of these signals is subject to an independent delay. Using a Lyapunov-based approach, sufficient conditions for stability that depend on each time delay are found for a range of proportional control gains. Numerical results show that the regions of time delays for which the system is stable are reduced as the proportional gain increases. Time domain simulations validate these stability regions and show the varying responses for the two control implementations and different values of the proportional gain.

10aAA14-0061 aWilches-Bernal, Felipe1 aCopp, David, A.1 aGravagne, Ian1 aSchoenwald, David, A. uhttps://ieeexplore.ieee.org/document/8600640/01700nas a2200145 4500008004100000245010300041210006900144260003400213520114300247100002001390700002701410700001801437700002601455856007301481 2017 eng d00aTime-domain analysis of power system stability with damping control and asymmetric feedback delays0 aTimedomain analysis of power system stability with damping contr aMorgantown, WVbIEEEc09/20173 aPower systems can be stabilized using distributed control methods with wide-area measurements for feedback. However, wide-area measurements are subject to time delays in communication, which can have undesirable effects on system performance. We present time-domain analysis results regarding the small-signal stability of a two-area power system with damping control subjected to asymmetric time delays in the feedback measurements. We consider two wide-area damping control implementations. The first is implemented with a High Voltage DC transmission line, and the second uses distributed Energy Storage devices. Numerical results show regions of stability for the closed-loop systems that depend on the time delays and the choice of the control gain. These results show that increasing the control gains cause the systems to be less robust to time delays, and, under certain conditions, increasing the time delays can have a stabilizing effect. Furthermore, we provide analysis of time simulations and eigenvalue plots that verify these stability regions and show how stability is affected as time delays increase.

1 aCopp, David, A.1 aWilches-Bernal, Felipe1 aGravagne, Ian1 aSchoenwald, David, A. uhttps://certs.lbl.gov/publications/time-domain-analysis-power-system