Papers by Polamraju V.S.Sobhan
Information Technology in Industry, Mar 24, 2021
Recently, waste heat energy recovery has attracted the attention of many researchers. The power c... more Recently, waste heat energy recovery has attracted the attention of many researchers. The power conversion efficiency of Thermoelectric Generator (TEG) system is enhanced by designing suitable MPPT controller. In this study a robust nonlinear control technique based on synergetic control theory is designed to extract maximum power from Thermoelectric Generator system (TEG). The designed synergetic control law ensures the fast convergence towards maximum power operating point without any oscillations under the presence of system uncertainties and variable temperature conditions. The TEG system comprises of a Thermoelectric Generator module, power converter, maximum power point tracking algorithm and load. The simulation results show viability of proposed strategy in comparison with Perturb and Observe (P&O) method under variable temperature.
Improved internal model controller design to control speed and torque surges for wind turbine driven permanent magnet synchronous generator
ABSTRACT
Rotor levitation by Active Magnetic Bearings using Fuzzy Logic Controller
... produced by a single two pole electromagnet can be shown to be given by the following equatio... more ... produced by a single two pole electromagnet can be shown to be given by the following equation where I is the total current in the magnet coils, z is Rotor Levitation by Active Magnetic Bearings Using Fuzzy Logic Controller Polamraju.VSSobhan 1 , Dr. GVNagesh Kumar 2 ...
International Journal of Intelligent Enterprise, 2021
The incorporation of renewable energy resources (RERs) into electrical grid is very challenging p... more The incorporation of renewable energy resources (RERs) into electrical grid is very challenging problem due to their intermittent nature. This paper solves an optimal power flow (OPF) considering wind-solar-storage hybrid generation system. The primary components of the hybrid power system include conventional thermal generators, wind farms and solar photovoltaic modules with batteries. The main critical problem in operating the wind farm or solar PV plant is that these RERs cannot be scheduled in the same manner as conventional generators, because they involve climate factors such as wind velocity and solar irradiation. This paper proposes a new strategy for the optimal power flow problem taking into account the impact of uncertainties in wind, solar PV and load forecasts. The simulation results for IEEE 30 bus system with genetic algorithm (GA) and two-point estimate method have been obtained to test the effectiveness of the proposed optimal power flow strategy. Results for a sample system with GA and two-point estimate OPF, and GA and Monte Carlo simulation have been obtained to ascertain effectiveness of the proposed method.
International journal of engineering & technology, Feb 9, 2018
The bearingless switched reluctance motor (BLSRM) is emerging as an attractive option for modern ... more The bearingless switched reluctance motor (BLSRM) is emerging as an attractive option for modern industrial applications because of the features, such as compact size, lubrication and seal free performance, long life and ability to rotate at very high speed and high power. The control approach is extremely fundamental to a steady operation because of its highly nonlinear, multi variable and open loop unstable nature. This paper presents a single neuron based rotor suspension control of a 12/14 Hybrid Pole BLSRM with autonomous rotation and suspension poles. This hybrid pole structure produces the suspension force linearly with respect to rotor position and independent of the torque characteristics. Implementation of a non model based Single neuron adaptive PID Controller by avoiding the modeling complexity is proposed. Experimental results demonstrate that the proposed controller maintains the rotor in the center position as well as the speed tracking and disturbance elimination performances independently.
International Journal of Power Electronics, 2020
Rotor vibration control during start up, acceleration and deceleration phases is one of the key p... more Rotor vibration control during start up, acceleration and deceleration phases is one of the key problems besides stable levitation, in high-speed applications of bearingless switched reluctance motor (BSRM). In this paper, an effective intelligent sliding mode controller is proposed for suppressing the rotor vibration due to residual unbalance and external disturbance during levitation and motoring phases. The parameters of time-varying sliding surface for avoiding high control gains and chattering are adjusted integrating the sliding mode control (SMC) and features of fuzzy logic control. The experimental studies conducted on a prototype BSRM system confirm that the application of fuzzy SMC guarantees the robust performance with less chattering under model uncertainties and unknown external disturbances compared to classical sliding mode controller.
International journal of engineering & technology, Feb 9, 2018
Motors working in extreme conditions such as ultra high and low temperatures, high contamination,... more Motors working in extreme conditions such as ultra high and low temperatures, high contamination, high purity etc. require high maintenance of mechanical bearings and the regular lubrication. Hence there is a need of a motor without mechanical bearings and lubrication in addition to simple in control and less maintenance. There by, bearingless motors (BLMs) gain more attention. The bearingless switched reluctance motor's (BLSRM) is simple in construction and economical in addition to high speed capacity and high torque to inertia ratio. The magnetic nonlinearity arising due to double salient structure makes rotor eccentric displacement control and speed regulation complicate and needs robust control methodology such as sliding mode control (SMC) which has integrity, high certainty and rapid dynamic response when compared to typical controllers. Sliding mode can be realized with distinct classical reaching laws. This paper presents design and implementation of a SMC for a 12/14 BLSRM and the dynamic performance is endorsed by simulation using Matlab software.
Enhancement of Line-Based Voltage Stability of Energy System with Thyristor Controlled Series Capacitor Using Cuckoo Search Algorithm
Lecture notes in mechanical engineering, 2020
Preserving stable conditions on encountering with small disturbances under normal or slightly ove... more Preserving stable conditions on encountering with small disturbances under normal or slightly overloaded conditions is termed as voltage stability. Maintaining voltage stability is one of the leading factors for energy system networks. In this paper, new line established voltage stability index entitled fast voltage stability index (FVSI) is proposed for optimal placement of Thyristor Controlled Series Capacitor (TCSC). Optimal tuning of TCSC is obtained using cuckoo search algorithm (CSA) to increase the voltage stability of the energy system established on minimization of total voltage deviation of the system. The CSA is coded in MATLAB and the performance is tested on IEEE 30 bus system with voltage deviation minimization as an objective function. TCSC is a series-connected device in the flexible alternating current transmission system (FACTS) family. It was capable of controlling the power flow through the line and also controls the line-based voltage stability. In this paper, TCSC is merged in CSA-based Power Flow to optimize the total voltage deviation. Results attained by CSA are related to that attained by genetic algorithm (GA) in both without and with TCSC conditions. These results show that CSA produces better results compared to GA for solving optimal tuning of TCSC.
Assessing the Risk of Reliability of Three Phase GIS Under Various Multiple Abnormalities
2021 IEEE 2nd International Conference On Electrical Power and Energy Systems (ICEPES), 2021
In today’s world, the installation of supporting insulators is critical for the working condition... more In today’s world, the installation of supporting insulators is critical for the working condition of 3-ø gas-insulated bus duct (GIBs), which is primarily dependent on concentration of electric fildstres on the spacer’s interface. Electric field stress must be reduced seems at the triple junction (TJ’s). GIB insulator breakdowns are caused by a variety of abnormalities such as delamination, protrusion, voids, particles and depressions. These imperfections have a negative impact on the field distribution along the spacer, de-energizing whole GIB and resulting in a significant economic loss. In this article, the post insulator with Functionally Graded Material (FGM) be intended in the direction of diminish huge field near TJ with establishment of metal inserts near zero enclosure end for a 3-ø GIB with multiple abnormalities in each and every grading (multiple voids with and without particles, multiple delamination’s with and without particles, multiple protrusions with and without particles, multiple depressions with and without particles, etc.). FGM are randomly distributed using various composite material doped with varied permittivity values to achieve a balanced electric field. The electrical stress is estimated by altering the diameters of each and every defect for various working voltages for various shapes, sizes and gradings of FGM among various permittivity values, and the findings were presented.
Boost PFC converter based on intelligent SM controller
2017 IEEE International Conference on Electrical, Instrumentation and Communication Engineering (ICEICE), 2017
In this paper a new sliding surface is introduced with fuzzy current sliding mode (SM) control to... more In this paper a new sliding surface is introduced with fuzzy current sliding mode (SM) control to overcome noise effect of differentiator in general current SM control. performance comparison of has been done on general SM control to the Fuzzy current SM control to Single phase AC/DC boost converter for achieving high power factor. This work is carried out in MATLAB/SIMULINK software. The converter is designed for 110V, 50 Hz AC input and 400V DC output.
International Journal of Engineering & Technology, 2018
Now-a-days to ensure power continuity and system’s reliability the protection system is to be des... more Now-a-days to ensure power continuity and system’s reliability the protection system is to be designed properly for distribution systems to handle the faults to avoiding the damage to the equipments and to the service engineers. Different types of relays with different working principles are used to detect different types of faults in the system. In order to avoid mal operation of relays, proper coordination is to be carried out. The objective of this paper is to maintain the relay coordination as well as to decrease the working time of relays by optimizing the values of time dial setting (TDS) using linear programming problem technique (LPP). The inequality constraints guarantee the coordination margin for each primary or backup relay pairs having a fault very close to the primary relay. Simulation is carried out on a IEEE 15 bus balanced radial distribution system with 3 different types of relays namely standard inverse, extremely inverse and very inverse relay and the results are...
Indian Journal of Science and Technology, 2016
In this paper PV fed two stages DC-DC converter has been designed and implemented for home applic... more In this paper PV fed two stages DC-DC converter has been designed and implemented for home applications .In two stages first stage consists of step down converter and second stage consists of step up converter connecting in cascade manner and power is transfers through both the stages. Here boost stage for step-up the voltage given by buck converter which is step down stage and will give required voltage to operate the load. By using P&O based MPPT algorithm maximum power has been extracted from the PV system. The proposed model has been implemented by using MATLAB / Simulink and results are verified experimentally.
Implementation of Static VAR Compensator for Improvement of Power System Stability
2009 International Conference on Advances in Computing, Control, and Telecommunication Technologies, 2009
Static VAR compensator (SVC) is incorporated in Newton Raphson method in which Power Flow Solutio... more Static VAR compensator (SVC) is incorporated in Newton Raphson method in which Power Flow Solution is a solution of the network under steady state conditions subjected to certain constraints under which the system operates. The power flow solution gives the nodal voltages and phase angles given a set of power injections at buses and specified voltages at a few, both
Optimal Power Flow by Newton Method for Reduction of Operating Cost with SVC Models
2009 International Conference on Advances in Computing, Control, and Telecommunication Technologies, 2009
The optimal power flow is a power flow problem in which certain variables are adjusted to minimiz... more The optimal power flow is a power flow problem in which certain variables are adjusted to minimize an objective function such as cost of the active power generation or the losses,while satisfying physical operating limits on various controls, dependent variables and function of control variables. Current interest in OPF covers around its ability to solve for the optimal solution that
Look Up Table Based Fuzzy Logic Controller for Unmanned Autonomous Underwater Vehicle
2009 International Conference on Advances in Computing, Control, and Telecommunication Technologies, 2009
... Unmanned Autonomous Underwater Vehicle PVSSobhan1, Dr. GVNagesh Kumar2 , M.Ramya Priya2 , and... more ... Unmanned Autonomous Underwater Vehicle PVSSobhan1, Dr. GVNagesh Kumar2 , M.Ramya Priya2 , and B.Venkateswara Rao3 ... The total Universe of discourse for each linguistic variable is portioned into 8 linguistic values (Large Positive (LP), ...
2008 IEEE Region 10 and the Third international Conference on Industrial and Information Systems, 2008
The underwater vehicle is six degrees of freedom model. The execution of spatial maneuvers are de... more The underwater vehicle is six degrees of freedom model. The execution of spatial maneuvers are determined mainly by the dynamic properties of underwater vehicle particularly controllability and stability. The control surfaces are situated at the rear end of the underwater vehicle which moves either vertically or horizontally (Pitch, Yaw, Roll, Pitch-rate, Yaw-rate etc.) used to steer the vehicle to run according to preprogrammed course as per logic till such a time the target is acquired. The underwater vehicle response is slow compared to air scenario due to constraints like higher density of water; the resistance motion is many hundred times greater than air. In this paper a rule-based fuzzy logic controller is designed for Yaw control, which is used for the rudder movement of an underwater vehicle. A Plant model is extracted using the input and output behavior and is assumed to the either linear time invariant first order or second order. Since the plant models obtained by the above process are very approximate, 50% variations are given on damping (ξ) and natural frequency (ωn) of second order plant and similarly the gain and time constant are varied for the first order plant. The performance evaluation of fuzzy logic controller under the above varying plant conditions is done and the results have been presented and analyzed.
Journal of mechanics of continua and mathematical sciences, Dec 28, 2019
A robust nonlinear control technique based on synergetic control theory is presented to extract m... more A robust nonlinear control technique based on synergetic control theory is presented to extract maximum power of standalone photovoltaic system (SPV). The synergetic control makes the controlled system robust under the presence of system uncertainties and external disturbances such as variable irradiance and temperature. The designed control law guarantees the fast convergence towards the maximum power operating point origin without any oscillations. The PV system comprises of a PV source, power converter, maximum power point tracking algorithm and load. The simulations results show effectiveness of proposed method in comparison with Perturb and Observe (P&O) method under different atmospheric conditions such as variable solar radiation and PV cell temperature.
The Proposed Integrated double buck boost converter features two capacitors, two inductors with o... more The Proposed Integrated double buck boost converter features two capacitors, two inductors with only one controlled switch.It is able to supply a solid-state lamp from the dc mains fed with PV panel.The converter mean time between failures can be increased with the cautious design of the converter by selecting the film capacitors. The designed Integrated double buck-boost(IDBB) converter will power the LED lamps with the renewable source i.e.,from the PV cell. The dc mains providing low output LED ripple current. The operation of the converter is similar to the cascad connection of two buck-boost converters,at which only one controlled switch is shared by the two stages.The proposed driver circuit is designed for 70W and MATLAB/Simulink software is used for implementation.
Advances in Electrical and Electronic Engineering, 2011
Paralleling of converter modules is a wellknown technique that is often used in medium-power appl... more Paralleling of converter modules is a wellknown technique that is often used in medium-power applications to achieve the desired output power by using smaller size of high frequency transformers and inductors. In this paper, a parallel-connected singlephase PFC topology using flyback and forward converters is proposed to improve the output voltage regulation with simultaneous input power factor correction (PFC) and control. The goal of the control is to stabilize the output voltage of the converter against the load variations. The paper presents the derivation of fuzzy control rules for the dc/dc converter circuit and control algorithm for regulating the dc/dc converter. This paper presents a design example and circuit analysis for 200 W power supply. The proposed approach offers cost effective, compact and efficient AC/DC converter by the use of parallel power processing. MATLAB/SIMULINK is used for implementation and simulation results show the performance improvement.
Fuzzy synergetic control based thermoelectric generator system for waste heat recovery in manufacturing process
International Journal on Interactive Design and Manufacturing (IJIDeM)
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Papers by Polamraju V.S.Sobhan