CAREER EPISODE 2
A. INTRODUCTION
CE 2.1
This section here represents the detail walk-through of the project entitled “A Review of Recent Development in Smart Grid Systems” which I undertook as my academic project while studying insert degree at Andhra University College of Engineering, located in Visakhapatnam, India. I did this project during the academic year of 2015.
B. BACKGROUND
CE 2.2
The rising concern regarding the energy security and climate changes in the energy sector is overcome by the Distributed generation, and the increase in the awareness in the public to decrease the pollutant gas emission also has led to the use of DGs. And this has resulted in the concept of smart grids as well as microgrids and its rise of interest among both consumers and producers. A smart grid system along with the microgrid system has swung the development of the information technology and communication system in the new era. This project here focused on these considerations, and case study was carried out for the design and implementation of smart grids along with the advancements in microgrid development.
CE 2.3
The main objective which I focused on this project for its successful completion is given as:
To minimize the operational cost of the VPP by considering the shifting and generation cost for all the period at a particular time horizon
To develop renewable energy for meeting the real-time demand
To design the system for the smart grid system by implementing different microgrid system
CE 2.4
I undertook this project as my final year project, and as I did it on an individual basis, the full responsibility for the successful completion of the project was mine alone. Starting from the brainstorming of the project, preparing the proposal and planning the project, right to the design and simulation was all my share of work, however I was guided by my project guide in all these instances. I checked the operation of the system to view the proper operation of the smart grid system where I made the case study of the 33 bus network model of the microgrid system. I carried out emulation of PV simulator, micro-generator and wind turbine, and made comparison of the performance of smart grid system with a conventional distribution system. Finally, I prepared the final report by taking help from the project guide and submitted it before the submission date.
CE 2.5
Figure attached in this subsection reflect the position I had been occupied with.
Fig: Organization Chart
CE 2.6
Keeping the objectives in mind, I performed certain tasks which are listed below:
To design for the smart grid system by implementing microgrid with load control, micro sources, and management
To emulate the PV array with the regulation of the DC supply
To emulate the microturbine by configuring the DC motor and the synchronous machine which was actually a small open cycle gas turbine
To perform the simulation of the smart grid system by using the SPIDER tools from the Matlab
To perform the case study of the smart grid system by taking the 33 bus network microgrid model
C. PERSONAL ENGINEERING ACTIVITIES
CE 2.7
I first studied the details of smart grid system by going through several papers to know about the existing smart grids, its design and implementations, shortcomings and future concerns. I collected the data like requirement of smart grids such as low carbon grid, economical grid, self-healing grid, two way communications and advance software for bringing variations at the distribution network to upgrade to the smart grid. I carried out emulation of the smart grid systems by performing emulation of PV simulator, wind turbine, etc. and compared the performance characteristics (I-V characteristics) against the conventional power transmission system.
CE 2.8
The project demanded the sound knowledge on different subjects of electrical and electronics engineering throughout its course, like the knowledge on power electronics, design of power transmission system, SCADA, design of substations, electrical devices and circuits, transformers, generators, etc. Also, I utilized knowledge of smart sensors and software communication for the integration of the AMI system and its synchronization with back-end applications. I referred the IEEE 2030.7-2017 for the verification of the micro-grid and smart grid system for the project system, IEEE 1547 and 2030 standard to gain the idea regarding the distributed energy. I applied my knowledge for simulation of the smart grid system in this project using the Matlab Simulink tool with Spider simulation platform. I referred to the IEEE 1451 for technological implementation of smart sensors.
CE 2.9
CE 2.9.1
I carried out research on the power transmission system, where I studied both traditional power network system and the power transmission network utilizing micro-grids. From the research, it was clear that the implementation of smart-grids required the overcoming of challenges like the installation of smart sensors for smart metering for the entire distribution network’s main elements for facilitating two-way communication contrast to the present traditional power distribution network with either no communication or one-way communication system. Another challenge was integrating and synchronizing the AMI system with back-end office applications for constant online monitoring. And other challenges were installing the fault detection system with real-time intelligent capabilities, integrating LV control as well as monitoring in real-time with the use of SCADA like system for high-voltage systems, etc. The smart grids with decentralized control are shown below:
Fig: Smart grid’s decentralized structure
CE 2.9.2
For the smart grid system, it is necessary to implement interconnection among the centralized structure of power grids and the distributed generations for control applications. For the collection of the data like connectivity, measurements and device model, the UMPCUs – Universal monitoring, protection and control units are to be installed at each of the grid’s components. IEC61850 and the Ethernet infrastructure standards were adopted for the improvement of the automation system’s response time, and the IEC61850 protocol facilitated the communication in the network, replacing conventional protocol being used i.e. serial communication. The challenge with this system is controlling the balance between consumption and generation. This was studied with PV power generation and its analysis. Shown below in the figures are micro-grids and communication architecture for the smart-grids system:
Fig: Microgrid with load control, micro sources, and management
Fig: Communication architecture in smart grid
CE 2.9.3
Then, in order to investigate the micro sources’ dynamic behavior, I performed emulations for micro sources at the laboratory scale i.e. emulation for the PV array, microturbine, and the Wind generator. I regulated the DC output of the power supply and emulated the PV simulator. This emulating module consisted of a variable DC power supply of 120V and 2KW capacity with set of DC motor generators of 4000rpm and 42V. The IV characteristic curve showed that the currents were 0.8A, 1.04A, and 1.3A for 0.6Sun, 0.8Sun and 1Sun at 0V cells voltage, and graph decayed exponentially to 0A in between 0.7-0.75V cell voltage. The graph is shown below:
Fig: I-V characteristics curve for a PV cell
CE 2.9.4
For the emulation of microturbines, which is used widely as a generating unit for DG systems in CHP system, I emulated the micro-generator by configuring a couple of the DC motor and the synchronous machine where it used small and simple cycle gas turbine. And, in the emulation of the wind turbine emulator, I considered in the main three parts that included generator, wind speed emulator and power electronic converter. Along with this, I used induction generator and dc motor for emulation. The emulator for wind turbine is shown below:
Fig: Wind turbine emulator
CE 2.9.5
I then proceed for the implementation of the micro-grid platform using the Spider simulation platform in Matlab, which was considered the two controlling methods i.e. centralized and distributed. I designed the model in such a way that the user or operator would select the control method by themselves which emphasized that the selection would be made depending upon the application of the user. I used Spider-simulation platform which used Matlab/Simulink tools in this project which was integration of the demand response. This module included different types of algorithms for DR implementation which included data mining of aggregation resources, optimization of energy resources, forecasting online tools, etc. This system spontaneously included the schedules of resources result as an input. For the transmission of the network simulation to the optimization block, this process was started from the network simulation in Simulink.
Fig; Spider simulation platform of the micro-grid
CE 2.9.6
I also performed the case study of the microgrid model for determining the validity and testing of a centralized microgrid control model for the 33 bus distribution network that included 68 DG units and 220 consumers where microgrid model was connected with the bus10 in this network. This system implemented the MATLAB/Simulink which was compatible with the OP5600. Here, I considered that microgrid would be owned by the VPP (virtual power plant) and all the resources containing the consumer and energy generator. I noted the aggregation of the DR and DG resources was done by the VPP and it was also capable of absorbing the energy from the main grid where it had low generation and high demand which emphasized the VPP’s active participation in electricity market. I noted that VPP reduced consumption to more specified period by defining the DR program. I noted the optimization of the generation and demand resources by the VPP for making decision and performing load shifting economically.
Fig: Microgrid model with 33 bus network
CE 2.10
TECHNICAL PROBLEMS AND SOLUTIONS
One of the major challenges I found during the research study for the conversion of the present traditional passive network to futuristic smart grid systems with the active network was about the implementation of two-way communication, which is very crucial for the monitoring and control of the power grids. This challenge could be overcome with the used of IEC61850 protocol for the replacement of traditional serial communication protocol, which also gave option of advanced protection through the direct exchange of information within the devices across the present station bus.
While performing the simulation of the smart grid system in this project from the Matlab/Simulink tools, I faced a problem from the radio hardware getting busy. It returned the warning message from the call to the info method which indicated that either the Simulink simulation was in progress or the receiver or transmitter block, the mask was open. What I did was, I stopped the simulation and closed the block mask, and then called the release method of the system and again proceeded for simulation, which solved the issue.
CE 2.11
CREATIVE WORK
In this project, I performed a case study for the design and implementation scenario of the smart grid system, researching the challenges and ways to overcome those challenges, which in itself is an innovative work. Here, I came up with the standards and protocol to implement two-way communication, and the innovative aspect of these smart grids is the capability of power flow in a bidirectional way than just the bidirectional data communication. And, the incorporation of the storage devices for operating the micro-grid in islanding mode successfully was an innovative strategy.
CE 2.12
For every project to obtain the required and proper result, it requires well managed coordination between all the personnel involved with the project, which I maintained here in this project. Proper coordination was made with the Project guide and internal guide in this project for sharing the different status of the project. My project guide encouraged me with the challenges imposed by the project and helped me throughout the project in resolving those challenges. I made good communication with the staff of the Electronics and Communication department, where I gained the idea and knowledge to overcome different issues that came in the period of project execution. I also received great help and support from the lab assistants during the simulation.
D. SUMMARY
CE 2.13
With the combination of the different parts from the microgrid, smart grid system was composed of the distributed generation of the electricity in this project. Here, electrical power was transmitted from smart meter, across the switched into the storage of the EV. With the smart meter, the information regarding the energy demand would be given to the consumer by EV and further, the information was allowed to pass from the smart meter to the grid operator. Workforce development, reduction in carbon dioxide, and job creation have resulted from the development of the smart grid as analyzed from the case study of the project system.
CE 2.14
This project focused on increasing the efficiency of the distributed generation system which was, again increased by the smart grid system or model where microgrid system was implemented. After completing the designing of the system, I then proceed for the simulation which I did by using MATLAB Simulink with the Spider simulation platform. I also performed the case study of the model by taking the microgrid of 33 bus network.
CE 2.15
This project made me acquainted with the different electrical and electronic concepts of the project, especially about the smart grid system. I learned to use the SPIDER tools of the Matlab where I performed the simulation of the system. I also gained the idea about the proper communication skill which I utilized in this project to make proper discussion with the project guide.