BI-DIRECTIONAL ELECTRIC VEHICLE FAST CHARGING STATION WITH REACTIVE POWER COMPENSATION.

Presented by,M.SWATHI

M.E., Power system engineering

Guided by,Dr.M.SARAVANAN Professor, EEE Dept,

Thiagarajar College of Engineering.

Objective

• To minimize the voltage impact due to electric vehicles fast charging in low voltage distribution network during peak load condition.

• The reactive power compensation is realized by simple direct voltage control method.

• The fast charging of electric vehicles is controlled by the switching of power converter modules with new constant current/reduced constant current approach.

Need For Battery Electric Vehicle

• First introduced in 19th century.• Attracts globally for its zero tailpipe emission and

used as a effort to reduce the dependence on fossil fuel and CO2 emission.

• Replaced the internal combustion engine due to invention of muffler and electric starter.

• Has battery storage and charger to control the bi-directional flow of real and reactive power.

Charging Of Battery And Its Impacts On Grid.

• SLOW CHARGING: Inexpensive way to charge and does not draw much

power from the distribution network. Takes about 6-8 hours to fully charge the depleted

battery.• FAST CHARGING: Drains very high power from the grid and takes 30

minutes to charge 80% of the battery capacity.• IMPACTS DUE TO CHARGING OF BATTERY : Harmonics; power demand load profile; system

losses; voltage profile; transformer overloading.

Literature Survey.

NAME OF THE AUTHOR

TITLE OF THE PAPER

PUBLICATION INFERENCE

Kejun Qian; Chengke Zhou; Malcolm Allan and Yue Yuan.

Modeling of Load Demand Due to EV BatteryCharging in Distribution Systems.

IEEE transactions on power systems, vol. 26, no. 2, April 22, 2011.

Stochastic method developed to find the stochastic nature of the start time of battery charging and initial battery state of chargesTakes into account the future changes in electricity tariff.

Bao K; LiS; Zheng h;

Battery charge and discharge control for energymanagement in EV and utility integration

IEEE power and energy societygeneral meeting

Principle Of Bi-Directional Power Transfer.

CONDITIONS FOR POWER TRANSFER:d1 > d2 Real power transfer from Bus 1 to Bus 2d1 < d2 Real power transfer from Bus 2 to Bus 1V1 > V2 Reactive power transfer from Bus 1 to Bus 2V1 < V2 Reactive power transfer from Bus 2 to Bus 1

Configuration Of Grid Connected EV System

Control Block Diagram Of AC/DC Converter.

Control Block Diagram Of DC/DC Converter.

Block diagram

Control scheme

• Communication based control system used in microgrid is less reliable since any communication link malfunctions will likely lead to instability

• Communicationless control based on the classical droop operating principles in microgrid is therefore preferred.

• Conventional droop control method using PI controller for active power sharing in hybrid microgrid will be implemented.

• The controller in a hybrid micrgrid manages the power sharing among the DGs in the microgrid by implementing droop controller equation.

f−fo = −Kp (P−Po)V−Vo = −Kq (Q−Qo)

fo and Vo are rated frequency and grid voltage respectively.

Po and Qo are the (momentary) set points for active and reactive power of the inverter respectively.

FULL BRIDGE CONVERTER

PWM SIGNAL FROM CONTROL

SCHEME

ENERGY STORAGE

Active and reactive power droop characteristics of an ac sub-grid

Active power droop characteristic for a dc subgrid

S.No Month WORK STATUS1

2

3

4

5

June’2014

June’2014

July’2014

August’2014

September’2014

Literature survey

Problem statement

Control scheme development

Implementation(power sharing)

Document and paper work

Completed

Completed

Yet to complete

Yet to complete

Yet to complete

Action Plan

THANK YOU