V2G Battery Charger for Electrical Vehicles

2017 ELE Engineering Design Project (DX06)

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Faculty Lab Coordinator

David Xu

Topic Category

Power / Controls

Preamble

The battery chargers for EV is usually energy unidirectional from grid to vehicles. The EV can be considered as a larger energy storage device, which can be used to support the grid operation whenever additional energy sources are needed. To enable this technology, bi-directional battery charger are required. The charger convert the grid energy into DC and charge the battery. It can also be controlled to discharge the battery and support the grid when the grid is in peak demand.

Objective

The objective of this project is to design a bidirectional battery charger at prototype level.

Partial Specifications

The specifications of the battery charger are:
1) full power at 500W (prototype level).
2) Single phase 120VAC input, 60Hz.
3) Nominal 48V DC output with charging capability up to 10A.
4) Energy bidirectional.
5) The grid side current THD<5%
6) Galvanic isolation between grid and battery

Suggested Approach

It is suggested to use single phase AC/DC converter plus bi-directional DC/DC converter with high frequency transformer for galvanic isolation. The group should study the dual active bridge with bi-directional AC-DC converter.

Group Responsibilities

The group should be responsible for project management, project demo and project reports

Student A Responsibilities

Student A should design the main power circuit for the charger with proper sensors

Student B Responsibilities

Student B should design the digital control system with signal conditioning circuit. The digital controller should be able to control the power circuit and accept the sensors' output.

Student C Responsibilities

Student C should write the program to control the main power circuit with proper algorithm. The energy bidirectional command is input from the human interface.

Course Co-requisites

ELE654