CHARGING OF PLUGIN ELECTRICAL VEHICLE

Task 4: Advanced managing strategies for multiple charging requests in an electrical grid (The “smart” approach).

In task 4, we analysed the effectiveness of smart strategies in which the charging processes of each user are scheduled on the basis of a more sophisticated priority criterion rather than simply considering only the arrival time, and the charging rate of each user is adapted to the grid load condition during the charging process.

We firstly considered the following priority and charging rate assignment functions:

The priority function (1) is formulated to assign priority to the users on the basis of both the amount of power required and the electricity rate they are disposed to pay. The influence of each of these aspects (power required and electricity rate) on determining the user priority can be adjusted by tuning the weighting coefficients a and b, with a+b=1.

The charging rate assignment function (2) consists in distributing the energy required by each user over the entire time period available before the user leaves the system.

Since the energy still required and the time available for each user change during the process, the implementation of the smart strategy requires a “frequent” communication about the user state of charge, and the updating of the priority and charging rate at regular intervals. The duration of these intervals is indicated as time resolution. In this task, we used a time resolution of 0.25 h. 

Task 5: try the effectiveness of your own advanced managing strategy.

In this task we carried out several simulations by introducing different smart strategies. In particular, we experimented different ways of assigning the priority of the users and different time resolution values. 

Task 6: Large scale scenario.

In this final task we evaluated the effectiveness of the different strategies previously analyzed in a large-scale scenario in which several grid nodes are considered. We considered different Uniform and Gaussian profiles for the electricity rate and the arrival and departure times of the users. 

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CHARGING OF PLUGIN ELECTRICAL VEHICLE USING MATLAB

Stage  1: PEV charging in a conventional distribution grid

Task 1: Understanding basic battery charging parameters.

In Task 1, we dealt with the charging process of a single PEV to familiarize with the basic concepts about battery charging. We selected different values of the available power from the grid, the battery charging rate and capacity, the initial state of charge and the user arrival and departure times in order to evaluate when the user is actually satisfied in terms of state of charge at the departure time.

 

Task 2: A real case of study: multiple charging requests in a conventional electrical grid (The “superdumb” approach).

In Task 2 we simulated the evolution of a local node of the distribution grid in which six PEVs have to be charged by using the so-called “superdumb” approach. In this case, the electrical grid is a conventional one, without any additional feature to support specific procedures or strategies to manage the vehicles charging. No communication is then possible between the PEVs and the utility in order to adapt the charging process to the grid load conditions. This means that the charging process of a PEV starts when the vehicle is plugged in and it is performed at the maximum charging rate allowed by the battery (provided that enough power is available from the grid at the time of plug-in). In the case when the power request exceeds the available power at that time, the charging request is rejected and the user cannot charge his battery. We performed several analyses by considering different realistic user profiles in terms of battery capacity, charging rate, arrival and departure times.

Task 3: Simple managing strategies for multiple charging requests in an electrical grid (The “dumb” approach).

In Task 3 we used the “dumb” approach, which is still a First-Come-First-Served strategy in which the charging process of a PEV is performed at the maximum charging rate, provided that the grid is capable of supplying the required power. However, in the “dumb” scenario, users can communicate to the grid manager their arrival and their (expected) departure times, the required energy to complete the charge as well as the instant at which they are actually fully charged. Thanks to this information exchange, a kind of negotiated charging can be implemented: if a user cannot be served at the time of arrival, its charging request is not completely rejected, but just queued until sufficient power becomes available (obviously, if power is available before the user departure time).

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Electrical Final year Project 2014

CHARGING OF PLUGIN ELECTRICAL VEHICLE--

Plug-in electric vehicles (PEVs) may guarantee significant advantages with respect to traditional gasoline-fueled vehicles in terms of:

• greenhouse gas emissions reduction;

• energy consumption reduction;

• air quality improvement;

• oil consumption reduction;

• higher drive comfort.

Owing to all these potentially significant societal benefits guaranteed by transport electrification, PEVs are expected to diffuse rapidly over the next few years.

Unfortunately, the resulting energy request for vehicle batteries recharging may create overload conditions for the electrical grid. It is then necessary to develop ad hoc strategies to manage the charging of these vehicles and consequently to adapt the grid infrastructure.

The project encourages you to cope with the very hot real-world problem arising from the increasing demand for charging Plug-in Electric Vehicles through the electrical energy distribution grid. You will analyze the effect of multiple quasi-contemporary charging requests on the grid, hence discovering how, as the number of users to be charged increases, either the grid collapses or the user requests may not be entirely fulfilled. You will be asked to analyze the effectiveness of smart energy dispatching strategies and smart battery charging methods in mitigating (or completely overcoming) the grid overload problems. You will also experience some of the real-world engineering trade-offs commonly encountered in developing scheduling strategies for the management of a shared resource such as the energy available from the grid.

A study by  the Pacific Northwest National Laboratory showed that the use of PEVs with the existing power plants in the U.S. could result in a 30% improvement in energy consumption per Vehicle Miles Traveled (VMT), a 27% reduction in CO₂ emissions, and a 52% reduction in imported oil [1]-[3].

Moreover, PEVs offer the unique possibility of being supplied by using clean renewable energy sources. According to a study of the Berkeley Center for Entrepreneurship & Technology of the University of California, the total emissions of the U.S. vehicle fleet would even be reduced by 62% by 2030 if about half of the fleet were powered by clean electricity. Owing to all these potentially significant societal benefits guaranteed by transport electrification, PEVs are expected to diffuse rapidly over the next few years. Indeed, electric vehicles are predicted to account for 64-86% U.S. sales of new light vehicles by 2030 [4].

Typically, PEVs require 0.2-0.3 kWh for a mile of driving and are characterized by battery capacity values in the range of 8-55 kWh. As a consequence, the additional demand for electric power required to charge a large fleet of PEVs in reasonable time may add a significant load to the distribution grid. For example, a study of the Joint Research Centre of the European Commission carried out for a real case study has recently shown that the maximum electric power request would increase by about 30% if PEVs should reach 25% of the vehicle fleet [5].

In a similar scenario, the presence of several contemporary charging requests could cause overload conditions in local nodes of the grid if the charging processes of the PEVs are not properly managed and scheduled. These overloads might lead to interruptions and/or unbalanced conditions which may degrade the quality of service, increase line losses and damage utility and customer equipment [3], [5].

It is therefore mandatory to develop innovative strategies for the scheduling of the battery charging process to avoid dangerous grid load conditions. Unfortunately, both electrical distribution grids and charging systems available nowadays are essentially “dumb” structures that offer no (or very poor) interacting capabilities. Thus, at the present time, the only possible working modality is to start the charging process of a PEV just when the vehicle is plugged in (or, at most, with a delay fixed by the user) without any dynamic adaptation mechanism of the charging conditions to the actual grid load. Clearly, the actual implementation of innovative strategies to overcome the problems discussed will require the combined development of smart grid infrastructures and advanced charging systems capable of reciprocal interaction. Only pursuing this multifaceted “smart revolution”, in which the engineers’ contribution is fundamental, it will be possible to support PEVs diffusion and to benefit from the potential huge advantages deriving from their extensive penetration worldwide.

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Electrical Seminar Topic: Smart Grid

Seminar Topic:

Seminar topics during under graduation course enhances the student to look beyond the textbooks and make them innovative. Seminar topics should be chosen in such a manner that the topic should be simple and explains about the present technology which can be find very little in text books and should be useful to audience. I am introducing a topic called SMART GRID so that  you can add the required resources and present in a seminar or can do a mini projects which helps during the placement.

Electric Grid:

Electrical Grid is an interconnection of power system constitutes generating plants, transmission network and distribution system ( to consumer ends). In normal grid, energy losses takes place due to the poor transmission and distribution networks including power thefts which results in loss in economy.No communication exist between the consumers and grid authorities. Power consumed is charged at same rate during all the day. So many flaws in today power grid makes it weak to sustain small disturbances.

Smart Grid:

Smart Grid is an an intelligent, future electricity system that connects all the generating systems (supply), grid and distribution systems ( consumer terminals) through an intelligent communication system.Smart Grid is a family of network control systems and asset management tools, empowered by sensors, communication pathways and information tools. Simply smart grid is an secure integration of electrical and information infrastructures.

Smart Grid at Consumer's side:

Major focus on the smart grid is on the distribution level or consumers. Demand is what drives the supply, so better management at consumer level helps the overall system. Important component of smart grid is 'smart metering'. Older meters connected to consumers just indicated the units consumed by the consumer. Smart meters evolved in to advanced metering system where the meter not only stores but also communicates loads and other power statistics in real time and even advice the consumers for better and optimal load control for reduction in prices. Smart grid explains and gives choice to the consumers to decide the timing and amount of power consumption based on the price per unit at that instant. Thus smart grid provides many wide features to the consumers for reducing the electricity bills and participating the consumers in improving the performance of the grid.

Smart Grid at Transmission side:

Smart grid helps the Generation and Transmission companies in dealing effectively with the power thefts and system losses through smart metering and advanced communication features. This also reduce in the reduction in the CO₂ emissions in to atmosphere.

Thus smart grid helps in reducing the losses, electricity bills and global warming and makes the electrical grid stronger to disturbances.

Please find some more sources related to this and i hope this can become a good seminar topic as it is the emerging technology and everybody talking about. Add some surveys, reports and case studies while presenting the seminar topic which makes the subject more informative and useful. 

 Resource link from Wikipedia Smart Grid

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How to Prepare Technical Paper for Presentation

Technical papers preparation:

How to prepare a technical paper for paper presentation? What should be the topic of the paper for presentation? What are the resources available for preparing a technical paper? These are some of the questions when you want to start preparing a technical paper when you are a beginner.

What is Paper Presentation?

Paper presentation is the abstract of the work which you have done. The ideas what you learned, observed and discovered when you are working on a particular topic is kept on a paper.

Different Types of Papers:

Technical papers are of three types

• Informative
• Modeling and Simulation
• Design and Manufacture

Informative: 

This type of papers will explain about the general information available. For eg: Consider latest trends and technologies used in Wind Power Generation. You can collect the information from different sources and organize them accordingly and can give your suggestions, comments on the topic and can make a paper.Technical papers of this type will be given less importance than the others because the direct work involvement which you do is less. However if you add a case study of your own then the quality of the paper will be improved. For eg: Energy Conservation or Audit, you do a case study for your University or big township and give your suggestions.

Modeling and Simulation: 

Many software tools available for simulation and carryout the studies and before designing simulation tests will be carried out  to study the design. Simulation tests will also be carried out for existing system to determine who it behaves during different operating conditions. Choose some IEEE or other journal technical papers, pick up the topic which will suit you the best. Model the system and try to simulate in different software tools (MATLAB,PSCAD, ETAP,EMTP,PSPICE..) and if possible do the experiment in your lab and analyse the results.

Design and Manufacture: 

This type of papers explains about designing and manufacturing an equipment. It explains about what are your requirements, who you design the equipment and manufacture it. What is the end result. For eg: you can take up designing SMPS based on your requirement and manufacture it accordingly.

Final Advice: Refer International Journals and Magazines and choose your topic. Do something different from the parent paper (what you taken up as reference). All the Best!

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