Introducing a Novel DC Power Flow Method With Reactive Power Considerations

Abstract

The DC power flow model is in widespread utilization in electricity-market applications and contingency analysis. The presented versions of this model can be classified into two categories: state-dependent, or Hot-Start, models and state-independent, or Cold-Start, models. A reasonable accuracy is reported in the literature regarding Hot-Start models as they take into account branch losses and bus voltages by using available base point. On the contrary, due to the absence of base point in Cold-Start models, branch losses must be either neglected or guessed (which is an uncertain precautionary measure), or evaluated by a cumbersome iteration process. In addition, the bus voltage profiles are inevitably considered to be flat. Hence, the accuracy of available Cold-Start models in different circumstances remains of great concern. This paper addresses this concern and unveils a new Cold-Start model that does not rely on a risky assumption. In other words, there will be no lossless or flat voltage profile assumption in the presented approach whereas the equations remain linear. Besides, the exact effect of the net reactive loads on phase angles is considered and, consequently, the reactive power balance equations are reflected in the model for the first time.