Marc Paupert

Current unbalance reduction in three-phase systems using single phase PHEV chargers

A method to reduce the current three phase unbalance using single phase Plug-in Hybrid Electric Vehicle (PHEV) chargers is presented in this paper. A reduction in the voltage unbalance has been achieved as a consequence of the mitigation of the current unbalance. The method performs the reactive power management on the PHEV charger in order to reduce the unbalance factor without affecting the battery charging time or charging power. The method works under restrictions to preserve the voltage quality. A simulation on Matlab-Simulink® of a three phase housing group with power profiles, initial states of charge, charging start time and PHEV category randomly selected is presented. A reduction of 50 % at some times in the day is illustrated.

PHEV charger model for active and reactive Power commands and its limitations

Abstract Locally reactive power management seems to be the most realizable ancillary service to be offer to the electrical grid. Therefore, the Plug-in Hybrid Electrical Vehicle (PHEV) might have an important role on this service due to its particular charging structure. This paper presents the response of a PHEV charger to active and reactive commands in V2G context. A charger structure controlled by sliding mode is presented and compared with the proportional integral (PI) control technique; the step responses to active and reactive power demands are shown. The boundary conditions related to control laws are also discussed.

Real-time plug-in electric vehicle charging strategies for current and voltage unbalance minimization

Plug-in electric vehicles (PEVs) have been proposed as one of the solutions to reduce transportation dependency on oil. Nevertheless, if PEVs are introduced as a new load on the grid without any charging strategy, the grids power quality will be deteriorated. Among the power quality parameters, current and voltage unbalances would be affected. This paper proposes a real-time strategy in order to minimize the current unbalance factor (CUF) caused by PEVs and housing on a common connection point (CCP) in a residential network. As a consequence of the CUF minimization, the voltage unbalance factor (VUF) is significantly reduced. The CUF at a CCP is formulated as a function of the loads in-phase and quadrature currents (PEVs and householders included). This objective function is minimized under maximum rating and charging priority constraints using algorithm Active-set. The minimization process is a part of the strategy which consists in adapting the optimization problem in real-time to changing conditions such as PEVs arrival and departure times, PEVs battery capacity variety, a random initial state-of-charge (SOC) and the householders consumption. The strategy was tested on a low voltage network simulated on Matlab /Simulink. Results show that the current balance index is increased more than 400%, the voltage unbalance index is reduced 17% and some of the CCPs in the electric network simulated, are re-balanced (based on the EN50160 standards definition) thanks to the CUF minimization.