Approximating line losses and apparent power in AC power flow linearizations

The linearized DC model is widely used in optimization of power systems but few studies evaluate the accuracy and feasibility of its solutions. This paper studies the source of errors in the linearized DC model and proposes three new models to improve its accuracy. In particular, it proposes a cold-start model capturing line losses and hot-starts models for approximating apparent power and more accurate phase angles. All of the models are linear programs and can easily be used as a building block for more complex applications. Experimental results on well-known benchmarks show the significant benefits in accuracy of the new models and the high correlation of their solutions with AC solutions.