Soft switching bidirectional DC-DC converter for energy storage systems
Bidirectional DC-DC converters are one of the most important parts of energy storage systems such as in plug-in hybrid electric vehicle (PHEV), the fuel-cell vehicle, renewable energy system, and uninterruptible power supply (UPS). Energy storage systems are used for storing energy and use it during fluctuations or supply outage. To improve its efficiency a soft-switching bidirectional DC-DC converter using a lossless active snubber is used. In this converter, Zero Voltage Switching (ZVS) of the main switches and Zero Current Switching (ZCS) of the auxiliary switches are always achieved by utilizing an active snubber which consists of auxiliary switches, diodes, an inductor, and a capacitor. In addition, by utilizing this active snubber, there is no reverse recovery problem induced by the poor dynamic performance of the MOSFETs body diode. Moreover, by adjusting according to loads, it is possible to achieve optimized overall efficiency throughout the whole loading range. This system is analyzed by the simulation in MATLAB/SIMULINK 2017. Hardware is implemented using dsPIC30f2010 microcontroller for 20W and 20 kHz and results are verified.
Published by: Sreelakshmi K S, Ninu Joy, Deena Mathew
Author: Sreelakshmi K S
Paper ID: V4I3-1618
Paper Status: published
Published: May 28, 2018
Fuzzy logic based three-level boost converter with Quasi-Z source
For conventional boost converters, switching stress will be more at high gain, in order to alleviate this problem three level boost converters are used. The mismatched voltage levels between the dynamic lower voltage and the required constant higher voltage of the DC link bus of the inverter can be solved using flying-capacitor based three-level boost converter with a quasi-Z source (TLBqZ). The operating principle of wide range voltage-gain for this topology is according to the effective switching states of the converter and the multi-loop energy communication characteristic of the quasi-Z source. The dynamic self-balance principle of the flying capacitor voltage is utilized. An analysis is done on the performance of the converter with PI and fuzzy controller. The fuzzy logic controller is used for switching pulse generation in the converter, as it is more advantageous over PI controller. An H-bridge inverter is fed from the converter that connects to the AC loads. The simulation of the circuit is performed in MATLABR2014a and waveforms are analyzed. An experimental prototype of the converter is implemented using dsPIC30F2010 microcontroller and results are verified.
Published by: Anju Ramesh T, Dr. Siny Paul, Neema S
Author: Anju Ramesh T
Paper ID: V4I3-1619
Paper Status: published
Published: May 28, 2018
Battery-ultracapacitor hybrid system for electric vehicles using new bidirectional quadratic DC-DC converter
Hybrid energy storage system is used with the objective of taking advantage of the best characteristics of each device, creating a system that is superior, than any of the devices used alone. Due to operational requirements of distributed generation systems, energy storage devices like batteries and super-capacitors, need bidirectional DC-DC converters to allow charge or discharge according to with the necessary conditions. A new battery-ultracapacitor hybrid energy storage system is proposed for electric vehicles. The main objectives of using ultra-capacitors in alongside batteries are: improving performance, increase the system efficiency and extend the battery life. In many applications, conventional bidirectional converters are inadequate since the specified range of input voltages and the specified range of output voltages call for an extremely large range of conversion ratios. A new bidirectional quadratic converter with high voltage gain in both step-down and step-up operation modes is used along with the ultra-capacitor. This converter is also characterized by a simple control technique since it is only necessary to control one power semiconductor for each mode. The additional power semiconductors remain always on or always off. In this project, an Ultra Capacitor is integrated with the battery in an Electric Vehicle using the new bidirectional quadratic buck-boost converter to improve the dynamic performance of the vehicle system and enhancing the battery life. The system model and the implemented control strategy has been simulated in MATLAB/SIMULINK software. The hardware of the proposed system is made. The control strategy is implemented using TMS320F28027.
Published by: Jithin K Mathews, Sija Gopinathan, Sera Mathew
Author: Jithin K Mathews
Paper ID: V4I3-1616
Paper Status: published
Published: May 28, 2018
Statistical approach to study the lithostratigraphic sequence in the Proterozoic Kolhans
Lithofacies succession in the Proterozoic Kolhan Group has been studied statistically using modified Cross-Association Analysis, Markov chain model, and Entropy function. The lithofacies analysis based on the field descriptions and their vertical packaging has been done for assessing the sediment depositional framework and the environment of deposition. Six lithofacies arranged, in two genetic sequences, have been recognized within the succession. The result of Markov chain and cross-association analysis indicates that the deposition of the lithofacies is in the Markovian and non-cyclic process and represents asymmetric fining- upward. The chi-square test has been done to test for randomness in hypotheses for lithofacies transition at the confidence level of 95%. The entropy analysis has been done to evaluate the randomness of occurrence of lithofacies in a succession. Two types of entropies are related to every state; one is relevant to the Markov matrix expressing the upward transitions (entropy after deposition), and the other, relevant to the matrix expressing the downward transitions (entropy before deposition). The total energy regime calculated from the entropy analysis showing maximum randomness, suggests that changing pattern in the deposition has been a result of rapid to the steady flow. This results from a change in the depositional pattern from deltaic to lacustrine deposit and sediment bypassing that finally generated non-cyclicity in the sequence.
Published by: Rohini Das
Author: Rohini Das
Paper ID: V4I3-1632
Paper Status: published
Published: May 28, 2018
Lung cancer detection system by fusion of CT and MRI images
Lung cancer is one of the common types of cancer in the world. It is hard to detect cancer and the affected level at an early stage. CT and MRI help us to detect this type of cancers at an early stage. Fusion of a CT and MRI images can be done for obtaining best results. However, in previous works, this method of diagnosis has not been carried out. In this proposed work combining of CT and MRI images can be done and the level of cancer in the lungs can be identified. Image fusion is used to identify the common features between the two images this can be used to improve the quality of the images for easy identification.
Published by: Gokulapriya V, M. Marikkannan
Author: Gokulapriya V
Paper ID: V4I3-1526
Paper Status: published
Published: May 28, 2018
An hybrid of PET and NIRS of non-invasive technique with clustering for detecting brain tumor
Segmentation is the process of partitioning the digital image into many segments which depends on pixels. It helps to identify objects or an irrelevant object in a particular area. The segmentation was based on color, texture and threshold methods. The main focus of this work is not only identifying the defected area in the brain but also analyzing the approximate location. So the clustering method is applied for grouping the similar objects. The non-invasive technique is a safe imaging technique uses today in research facilities and hospitals throughout the world. The comparing of non-invasive techniques like Positron Emission Tomography (PET) scan and the hybrid of Near-Infrared Spectroscopy (NIRS) and Electro-Encephalography (EEG) brain interfaces gives the best result to find the approximate location of the detected area in the brain with accuracy and stability.
Published by: Eniya Priya Darsini K
Author: Eniya Priya Darsini K
Paper ID: V4I3-1587
Paper Status: published
Published: May 28, 2018
