Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

The main objective of this work is to determine sensor fault in a Continuous Stirred Tank Reactor (CSTR) process using Unknown Input Observer (UIO). For any practical systems, there will be unavoidable disturbances and uncertainties, which leads to deviations in the plant output. Therefore it is essential in the design of any fault diagnosis system to consider these effects. CSTR equipped with a mixing device, and it runs at a steady state with a continuous flow of reactants and products. In CSTR, the outlet concentration is controlled by changing the volumetric flow rate. Initially, the data of the process were collected and preprocessed. Finally, the state space model was obtained using system identification tool in MATLAB. Pole placement technique is used for designing UIO for the system affected by input disturbances. The designed unknown input observer is used for generating a residual signal, and it is a deviation of plant output and observer output. The residual signal is zero during the fault-free condition. When a fault present, there is a deviation in the residual signal. In this work bias fault, drift fault was detected. Output observer also designed in this work to highlight the feature of the unknown input observer. Finally, it is observed that the unknown input observer has eliminated the input disturbances than that of output observer and faults was also detected effectively. © 2021 Elsevier Ltd. All rights reserved.

World University root node

Electrical

School of Electrical Engineering

Chennai Campus

Materials Today: Proceedings

Investigation of unknown input observer for sensor fault diagnosis for a CSTR process

Lighting is an important feature for the interior of a room as it produces a good state of mind, atmosphere, and beautiful appeal in living space. Light and lighting fixture create a pleasant and safe habitat besides adding style to the interior of a room. Moreover, as lighting consumes nearly 35% of the total electricity consumed in a building, LED drivers are proposed to increase energy efficiency. Lighting design is mandatory for the placement of lights to have good illumination, thereby lighting design is done for a two-bedded hostel room with fluorescent and LED lights and their performance is analyzed. A phase-shifted buck converter (PSBC) LED driver is designed and experimented for 24 and 6 W to retrofit the existing fluorescent lights in the two-bedded room. The results show that the output lumens and efficiency of PSBC LED driver are higher than conventional LED driver (CBC). Based on the PSBC experimental results, a lighting design is done using DIALux software for the existing room with fluorescent lights and a retrofitted room using PSBC and LED lights. The simulation results show that PSBC driver provides good illumination and has better energy savings. The estimated installation cost, energy savings, and energy efficiency for the PSBC driver and a conventional buck driver also prove that PSBC driver is a better alternative for energy savings. © Springer Nature Singapore Pte Ltd 2020.

Lecture Notes in Electrical Engineering

Lighting design for a campus hostel building using single-stage efficient buck led driver

To control the systems which operate in a repetitive mode is known to be a difficult task. For example, systems like robotic manipulators are used for doing the repetitive assigned task. This can be overcome by the iterative learning control (ILC) method. In this article, the DC motor model is discussed for controlling the speed of the motor by the design of an ILC algorithm, and its performance is compared with the conventional PID algorithm. The ILC algorithm is implemented for the minimum and non-minimum phase systems. The resulting response, absolute and integral absolute errors are plotted. The Z-N tuning method is used to implement PID control. The performance of the DC motor has been evaluated by comparing the Integral Square Error (ISE), Integral Absolute Error (IAE), and Integral Time Absolute Error (ITAE) with the conventional PID controller. © 2020 Published under licence by IOP Publishing Ltd.

Fulltext

IOP Conference Series: Materials Science and Engineering

Iterative Learning Control for a Repetitive 2D Process

The demand for lean protein is the main reason for raising domesticated birds in poultry farms for the purpose of farming meat or eggs for food. In these poultry farms, artificial lighting system is an essential factor for the success of the commercial production of egg layers and broilers. Lighting loads connected to the existing AC system requires DC power. Nearly 25% of the total power consumed in India is by lighting loads. Therefore, low-voltage DC distribution system is the new requirement of electrical network to improve energy conservation. In this paper, an energy efficient single-stage LED driver topology is proposed as a better alternative to fluorescent lights used in poultry farms. The proposed topology is a phase-shifted buck converter with reduced size of passive components. The converter is mathematically modelled and designed for a power of 24 W LED lights. An experimental prototype is developed for the proposed converter and the results are validated in terms of cost, energy savings, and energy efficiency with various other LED driver topologies like conventional buck converter and interleaved buck converter. Further to justify the outcome of the proposed LED driver, a case study is also done for poultry farms. © 2019, © 2019 IETE.

IETE Journal of Research

Performance Analysis of Single-Stage LED Buck Driver Topologies for Low-Voltage DC Distribution Systems

Energy efficient generation from renewable energy sources is of major concern nowadays. A horizontal axis marine current turbine (HAMCT) of diameter 1.9 m is modelled using the blade element momentum (BEM) scheme and the turbine output parameters are given as an input to the electrical system for a tip speed ratio (TSR) of 5 and a power coefficient of 0.4. The design aspects of a buck-boost converter with proportional integral (PI) and sliding mode controller (SMC) is investigated for HAMCT system, with the highest power output of about 15.6 kW for a water velocity of 3 m/s. A comparison between PI controller and SMC are analyzed for the tidal turbine conversion system to obtain the desired output voltage with high efficiency is discussed here. The dynamic variation on load side to be controlled with dual loop controller to regulate the output voltage and to optimize the input current. In this paper performance and resemblance of control techniques which include sliding mode controller and PI controller are analysed with step and bode plot response. The system is designed for an output voltage range of 0.38 kV to 2.4 kV which is suitable for DC microgrids. The performance of HAMCT coupled with PMSG and the power converter with a controller is modelled and designed under MATLAB/SIMULINK environment. © 2019 The Authors. Published by Elsevier Ltd.

Department of Ocean Engineering

VIT Unitversity

Energy Procedia

A performance analysis of tidal turbine conversion system based on control strategies

Most of the loads connected to the existing AC distribution system operate with low voltage DC power. Hence, there is a requirement to convert AC into DC power. Often there are many inefficiencies associated with AC to DC power conversion. To enhance the energy conservation, low voltage DC distribution system (LVDCDS) is suggested in this paper. Forty percent of the total power consumed in India is by lighting loads which make use of DC power. LVDCDS is an ideal choice to power lighting loads in residential and commercial buildings. This paper presents a detailed study of four different single stage, interleaved, non-isolated light emitting diode (LED) drivers for lighting load. All the topologies are developed in hardware and tested experimentally with controller implementation to provide a constant power of 70 W to power LED lights in the campus building. The installation cost, payback period, and energy savings for the converters connected to LVDCDS are analyzed and discussed in particular. © 2018, © 2018 Taylor and Francis Group, LLC.

Electric Power Components and Systems

LED Boost Driver Topologies for Low Voltage DC Distribution Systems in Smart Structured Buildings

High performance single stage LED drivers gain a lot of attention in the outdoor lighting applications. Efficiency and dynamics is a primary concern in LED drivers. To enhance the efficiency and dynamics of driver, a Multi- Device Integer Frequency Boost LED driver (MDIFBD) is proposed. The proposed driver has two switches where one operates at low frequency and the other operates at integer multiples of low frequency. The high frequency switch current is interleaved through the low frequency switch. Thus the converter can operate at two different frequencies, with simple control technique. The proposed driver exhibits improved steady state performance with low switching loss. The proposed converter is designed, mathematically modeled and simulated in MATLAB environment. The converter is also developed in hardware for 70W and tested for input voltage and load dynamics. The converter is tested experimentally and the results are validated for improved dynamics in comparison with conventional boost driver operating at low frequency and higher efficiency with high frequency. © 2018, Institute of Advanced Scientific Research, Inc. All rights reserved.

Journal of Advanced Research in Dynamical and Control Systems

Multi device integer frequency LED boost driver for outdoor lighting applications

In this paper, a Double Frequency Buck Driver (DFBD) using SiC diodes for LED lighting systems is presented. This topology enhances the efficiency of the Double Frequency Buck Converter (DFBC) by minimizing the switching losses in power diode. The design procedure, mathematical equations and efficiency calculations of the DFBD are discussed. A prototype of the Conventional Buck Converter (CBC) with Si and SiC diode, DFBC with SiC diode and Si diode is implemented for 10W LED in hardware. Experimental results are presented for the four different topologies to imply that the efficiency of the system increases with SiC diodes. In addition, the cost analysis and energy savings for a multi-storeyed official building are estimated for the DFBC with SiC topology and validated with the other topologies. © 2017 The Authors. Published by Elsevier Ltd.

High Efficiency Buck LED Driver Using SiC

Robustness of the controller is vital in many process industries. The robust controller will not only compensate for disturbance but also for the parametric variation in the process itself. This paper proposes the design of such a robust propositional-integral (PI) controller for a non-linear level control process, like hemi-spherical tank system, using volumetric observer. In a level control system, the volume has a linear relation to the differences in inflow and outflow, whereas the rate change in height is non-linearly related to the flow difference. The robustness of the proposed controller was enhanced by using volume error instead of level error. The volume error is derived by using a volumetric observer, which observes the tank volume and a volume estimator, which estimate the desired tank volume. This enables a linear controller like PI controller to be more robust over the entire span of tank height. The robustness of the proposed controller was compared with the conventional controller and its performance is validated by using the averaged performance indices like averaged-ISE, ITAE and IAE. Simulation results illustrates that the proposed controller has faster response and lesser oscillations. © Research India Publications.