PEV load and its impact on static voltage stability

Abstract

A global resurgence of electric vehicle has taken place as a sustainable alternative to fossil fuel dependent transportation. As a result, the new plug-in electric vehicle (PEV) charging load is emerging into power networks. Even though the environmental and economic benefits of electrified transportation are very much apparent, its impacts on power systems still need to be understood. This chapter develops a mathematical model of the PEV charging load, evaluates its impact on system steady state voltage stability and suggests effective remedies to overcome the stability impacts due to PEV charging on power grids. Load characteristics profoundly influence the static voltage stability of power systems. Therefore, it is important to understand the characteristics of this emerging PEV charging load and its impact on power system voltage stability. Hence, a load model for the power electronically controlled PEV battery charging load is introduced in this chapter. The proposed PEV load model consists of a combination of a constant power load and a voltage dependent load having negative exponential characteristics. Due to the voltage dependent characteristics of PEV, the conventional power flow equations require modifications in order to accommodate the PEV load. The required modifications to the Newton Raphson power flow algorithm are described in this chapter. The system studies carried out in this chapter found that PEV charging load cause negative impact on system voltage stability, hence effective remedial measures are introduced. Further, a computationally efficient index which has good physical interpretation is introduced for identifying voltage stability considered charging infrastructure.