Effect of Generator Flow Control Strategies on the Long Term Dynamics of a Model for Power Systems

Cascading component failure can cause system-wide blackouts in power systems. Complex system analysis of the long term dynamics suggests that power transmission systems operate near a critical point. Here the effect of generator operation in a model for power systems is investigated. Two opposing methods of dispatching generators are compared. These two methods are to minimize and maximize the line flows with respect to their limits across the system. These methods are also compared to an economic dispatch. It is shown that the generator dispatch method used affects the frequency distributions and other statistics of blackouts. Dispatching using the maximization method causes a reduction in the frequencies of all blackouts as measured by the amount of load shed. This reduction is concurrent with an increase in the investment in the transmission system. These observations suggest that economic dispatch, while attempting to increase reliability, actually decreases the robustness of the system.