Problem Statement: The controlled charging of EV batteries may lowers the charging time and reduces the overloading of different network components. The impact varies changing the value of each network component, on the other hand uncontrolled charging requires twice the components replacement. The large number of electric vehicles may be accommodated easily deploying flexible and sophisticated distribution network.
Project Goals: The first task is to develop ac-dc central converter station using discrete semiconductor devices, gate drivers, passive components, voltage and current sensors, and control platform. The charging and grid support functions will be verified experimentally. The second task is to develop dc-dc converters for EV fast charging and battery energy storage. The hardware components used for this converter are similar to the central ac-dc converter. The performance of fast chargers and energy management strategies will be verified experimentally.Finally complete the charging device, so that the charge can reach level 3.
Progress in Meeting Project Goals: Progress in Meeting Project Goals: Our first task began by doing the simulation for DC-AC using MATLAB and simulink, after accomplishing this task we can see if our results are correct by looking at the plots. We then started to do the experiment in real time using the DSpace. Once task one is done, we can begin the second task. Second task is to repeat the steps used for the first task, but this time for DC-DC. As our focus, is fast charging for electrical vehicles (EV) we want to have a three-phase rectifier (AC-DC) that can convert the AC voltage coming from the grid to DC and a converter (DC-DC) to regulate the voltage that is going to charge the battery. As it is known batteries can only be charged using DC voltage. Currently we are working on finishing the simulations to real time, once we are done with that part we can then later focus on the DSP. The DSP will be controlling the buttons of start, stop and reset as well as the LCD screen and the voltage going from the DC-DC converter to the battery. The LCD screen will be displaying how much time left is there to fully charge the battery and other simple functions. We also need two more things: First, to have a transformer that will provide galvanic isolation between the charging station and utility grid. Second, a filter that will reduce the AC currents harmonic distortion. However, we have these two things at the lab, so no need to build it, only do the connections. Lastly, we need to put everything together once we test that everything is working, and this needed to be completed by April 15th.
Assessment of Project Progress to Date in Comparison with Project Plan as Proposed: We have completed the simulation about AC-DC and DC-DC on Matlab. We have also completed the simulation about AC-DC on real time.
Projected Schedule to Complete the Project: We plan to use Matlab to build AC-DC, DC-DC circuits and simulate them to ensure the feasibility of the circuit. At the same time, we use Realtime for actual measurement to ensure the actual utility of the circuit. After that, we will use the digital signal processor for signal control (including screen and button connections). Finally, all components (including filter and transformer) are soldered to the enclosure to complete the fast charging model. The completion time is expected to be May this year. Refer to Table 1 for the specific completion date.