Identification Of Ev Charging Load Model And EV’s Effect Ondistributionvoltage

With the increasing number of the Electric Vehicles(EVs), charging load has become an important factor that affects the operation performance of the distribution network. To evaluate the risk causing by large charging load objectively, a proper tool for analyzation and one accurate charging model are essential. The model of electric vehicle battery charging load established on the DC side cannot be used directly during the distribution network analysis, and the constant-power model is too simple to describeall the typicle charging loads, which would easily cause deviations.To build a charging model for the voltage analyzationof distribute network, considering typical EV charging modes, this paper studied the compositon of charging model on the AC side and ananysized proportions of three different components mainly usingthe methods of identifitation and experiment data induction, through which built the static equivalent load model on the AC side, and applied it to the distribution network to analyze the way that charging load affected distribution voltage.According to the typical structure of a EV charger, this paper identified power-mode, impedance-mode and current-mode load from total load with least square method using data extracted through the simulation of electric vehicle battery charging behavior and studied its variations with changes of charging current, source voltage and SOC of batteries. By applying both the identified results and the one fold power-mode load to the simple system and distribution network, this paper analyzed and compared the effects of static voltage stability margin and the maximum transmit capacity.Besides the typical charging method, Tesla chargers offer a special charging procedureduring which thecharging powerwaves a lot. By testing on the charging process with two Tesla EVs(Model S 85 and Model S P85), related data on the AC side was obtained, based on which, this paper analyzed charing character under the Tesla intelligentcharging mode and described its advantages by comparing with the charging mode discussed before. Furthermore, this paper built a time-variantmodel of the special intelligentcharing process. Also, amethod of time-shifting was put forward to limit the.peak power while large numbers of EVs were charging. By this method, one charge station could support more EVs within its mamximum limited power.Air conditioning load and charging load are both sensitive to weather conditions and human activities, so the combination of those two loads may cause power shortage and have negative influence on the voltage stability of distribution network. This paper took IEEE33 distribution network as an example; calculated power flow wth charging stations accessed and analyzed the nodes’ voltage under different accessing circumstances. Moreover, this paper considered the situation that both air conditioning load(including normal and inverter air conditioners) and charging load were accessed and analized effects on the v oltage of distribution network which should be taken seriously.