G JAYAKRISHNA - Academia.edu (original) (raw)

Papers by G JAYAKRISHNA

Lecture Notes in Electrical Engineering, 2014

ABSTRACT The major power quality issues are voltage sag, voltage swell and voltage harmonics in d... more ABSTRACT The major power quality issues are voltage sag, voltage swell and voltage harmonics in distribution system. These power quality issues are solved by custom power conditioning devices such as Dynamic Voltage Restorer (DVR), Distributed Static Compensator (DSTATCOM) and Unified Power Quality Conditioner (UPQC). This paper presents the ability of Unified Power Quality Conditioner to mitigate voltage sag, voltage swell and voltage harmonics in distribution system. UPQC is modeled in MATLAB_SIMULINK environment with Fuzzy Logic (FL), Neural Network (NN) controllers. The performances of UPQC with two controllers are compared.

International Journal of Software Innovation

In recent years, distributed generations (DGs) are extremely fast in detecting their location, wh... more In recent years, distributed generations (DGs) are extremely fast in detecting their location, which helps to satisfy the ever-increasing power demands. The placement of energy storage systems (ESSs) could be a substantial opportunity to enhance the presentation of radial distribution system (RDS). The major part of DG units in RDS deals with the detection of ideal placement and size of the DGs, which efficiently balance the power loss and voltage stability. The ideal location and size of ESSs are examined in standard IEEE-33 and 69 bus systems, which is important to reduce power losses. Nowadays, several algorithms or techniques are modified for the development of hybrid algorithms to improve the quality of DG allocation. In this research, a hybrid shuffled frog leap algorithm (SFLA) with ant lion optimizer (SFLA-ALO) is proposed for the optimal placement and size of the DG and ESS in the RDS to reduce power losses and maintain the stability of voltage. The performance of the propo...

International Journal of Electrical and Electronics Research

The importance of distributed generation (DG) has increased recently as a result of the growth in... more The importance of distributed generation (DG) has increased recently as a result of the growth in commercial and industrial loads, which has put more pressure on conventional energy sources and utilities. Alternative power generation methods that can handle the massive load without endangering the environment are therefore urgently needed. The installation of Energy Storage Systems (ESSs) may give a substantial opportunity to enhance the aesthetic appeal of the distribution system. DG is a practical substitute for conventional energy sources, which have drawbacks for both the economics and the environment. It goes without saying that there are situations in which a large amount of land and money are required. However, improper DG location or sizing increases safety issues because to the increasing power loss caused by larger reverse flow from the load to the supply. In order to reduce power losses and maintain voltage stability, the ideal location and dimensions for the DG and ESS i...

This paper presents the design of an adaptive power oscillation damping (POD) controller for a st... more This paper presents the design of an adaptive power oscillation damping (POD) controller for a static synchronous compensator (STATCOM) equipped with energy storage. The proposed method is effective in increasing the damping of the system at the desired frequencies. First, the impact of active and reactive power injection into the power system will be carried out using a simple twomachine system model. A control strategy that optimizes active and reactive power injection at various connection points of the STATCOM will be derived using the simplified model. The effectiveness of the proposed control method to provide power oscillation damping irrespective of the connection point of the device and in the presence of system parameter uncertainties will be verified through simulation and results.

The modelling and simulation of modified SVPWM VSI fed three phase Induction motor drive are also... more The modelling and simulation of modified SVPWM VSI fed three phase Induction motor drive are also presented. The drive system is modelled using the blocks of simulink The Z-source inverter is a relatively recent converter topology that exhibits both voltage-buck and voltage-boost capability. The Z-source concept can be applied to all dc-to-ac, ac-to-dc, ac-to-ac, and dc-to-dc power conversion whether two-level or multilevel. Power electronic inverter is a circuit that converts direct power to alternative power. Inverters are commonly used to supply AC power from DC sources such as solar panels or batteries. It is widely used in industrial power conversion systems both for utility and drives applications. Induction motor is popularly used in industries due to ruggedness and robustness. Previous publications have shown the control of a Z-source neutral point clamped inverter using the carrier-based modulation technique. Z-source inverter based adjustable speed drive system (ASD) effec...

This paper discusses the theory and implementation of a class of distributed power converters for... more This paper discusses the theory and implementation of a class of distributed power converters for photovoltaic (PV) energy optimization. Resonant switched-capacitor converters are configured in parallel with strings of PV cells at the sub-module level to improve energy capture in the event of shading or mismatch. The converters operate in a parallel-ladder architecture, enforcing voltage ratios among strings of cells at terminals normally connected to bypass diodes. The balancing function extends from the sub-module level to the entire series string through a dual-core cable and connector. The parallel configuration allows converters to handle only mismatch power and turn off if there is no mismatch in the array. In general the power management architecture can impact the viability of solar energy, increasing energy capture while reducing costs and solving painful integration issues. The central inverter implements a maximum power point tracking (MPPT) algorithm that optimizes power...

EAI Endorsed Transactions on Energy Web, 2022

Power quality enhancement is one of the major concerns from the last few years due to fluctuation... more Power quality enhancement is one of the major concerns from the last few years due to fluctuations occurring in the power transmission and distribution. This paper presents the design of distributed generation system for reducing power quality problems in the distribution system and grid side supply. It involves the design of distributed generation using renewable energy source and also reverse voltage technique based multilevel inverter for integration into the grid. This paper also presents the design of fuzzy controller based modified synchronous rotating frame theory for regulating the DC link voltage and multilevel inverter currents. The system was simulated using MATLAB Simulink and the results are verified with single phase and three phase non linear loads.

This paper proposes a Space Vector Modulation (SVM)-based approach for the switching state redund... more This paper proposes a Space Vector Modulation (SVM)-based approach for the switching state redundancy of an n-level Flying Capacitor Converter(FCC) to carry out the voltage balancing task within the switching states. Capacitor voltage deviations are minimized to choose the proper redundant switching states among the available switching states. The performance of a grid-connected Five-level FCC under the proposed SVM strategy for various operating conditions is simulated and evaluated based on time-domain simulations in the MATLAB/SIMULINK. The simulation results demonstrate the capability of the proposed SVM strategy to regulate the capacitor voltages at their nominal reference values.

This paper deals with a Cuk dc-dc converter as a single-stage power-factor-correction converter f... more This paper deals with a Cuk dc-dc converter as a single-stage power-factor-correction converter for a permanentmagnet (PM) brushless dc motor (PMBLDCM) fed through a diode bridge rectifier from a single-phase ac mains. A three-phase voltage-source inverter is used as an electronic commutator to operate the PMBLDCM driving an air-conditioner compressor. The speed of the compressor is controlled to achieve optimum airconditioning using a concept of the voltage control at dc link proportional to the desired speed of the PMBLDCM. The stator currents of the PMBLDCM during step change in the reference speed are controlled within the specified limits by an addition of a rate limiter in the reference dc link voltage. The proposed PMBLDCM drive (PMBLDCMD) is designed and modeled, and its performance is evaluated in Matlab-Simulink environment. Simulated results are presented to demonstrate an improved power quality at ac mains of the PMBLDCMD system in a wide range of speed and input ac volt...

This paper discusses the design of a new transformerless single-stage single-switch double buck c... more This paper discusses the design of a new transformerless single-stage single-switch double buck converter (ISSSSDB) which integrates a buck-type power factor correction (PFC) cell with a buck-type dc–dc output cell in a special way. High input power factor can be obtained automatically by operating the PFC cell inductor in discontinuous conduction mode (DCM), where the well and tight output voltage is regulated by the DC-DC cell. The advantages of this converter are low voltage stress across the dc-link capacitor, low current stress on the switch, and high step down input to output voltage, low cost and reduced size. These characteristics makes the converter costefficient, easy-to-design, and suitable for the low-power and non-isolated applications. The results are validated by simulating ISSSSDB using MATLAB/Simulink.

Journal of emerging technologies and innovative research, 2018

B. Ravi teja, Dr. G. Jayakrishna,Akhib Khan Bahamani Assistant professor, Professor, Assoc.Profes... more B. Ravi teja, Dr. G. Jayakrishna,Akhib Khan Bahamani Assistant professor, Professor, Assoc.Professor Electrical & Electronics Engineering, Narayana Engineering College, Nellore, India ________________________________________________________________________________________________________ Abstract : This paper is designed in such a way that it overcomes this limitation by the use of solar energy. Hybrid Inverter with Solar Battery Charging System consists of an inverter powered by a 12V Battery. This inverter generates up to 230V AC with the help of driver circuitry and a heavy load transformer. This battery gets charged from two sources, first being the mains power supply itself and second from the solar power. If the mains power supply is available, then the relay switches to main power supply for supplying the load. This power supply also charges the battery for using it as back up the next time when there is a power outage. The use of solar panel to charge the battery gives an ad...

International journal of engineering research and technology, 2014

This paper presents a low cost single phase inverter with virtual DC bus for common mode ground l... more This paper presents a low cost single phase inverter with virtual DC bus for common mode ground leakage current elimination in PV systems. It concentrates on the removal of common mode ground currents in the transformer less PV systems using virtual DC bus concept. In addition to this, the virtual Dc bus provides a negative voltage level for the generation of negative ac grid current. Based on this idea, an inverter topology is designed, in which the virtual DC bus is created with the switched capacitor technology. It uses two switched capacitors, five power switches and only a single filter inductor, which results in reduced cost of the device. This inverter topology is modulated with two techniques such as unipolar sinusoidal pulse width modulation (UPSPWM) and double frequency sinusoidal pulse width modulation (DFSPWM) for a DC input of 400V from the PV panels. Simulated results concluded that the proposed inverter topology provides the reduced output current ripple, low THD and ...

Journal of emerging technologies and innovative research, 2018

In the field of Electrical Engineering, the transmission line plays an important role. During the... more In the field of Electrical Engineering, the transmission line plays an important role. During the transmission of electricity some faults occur in it. The main problems faced by transmission lines are damage of insulators, conductor corrosion, vibration damage, arching damage of conductors and leakage of current. Many lines are located in remote and rugged environments. Usually the workers who inspect these lines conduct the helicopter surveys or must climb the tower to check the line close proximity. In connection with the shortcomings of the current power transmission line inspection Transmission Line Monitoring System(TLMS) or Robot technology, a new electric power inspection leading to significant cost benefits in contrast to the conventional systems(Helicopters, industrial climbers etc.) is developed to improve the monitoring and control. The images of the line defects and potential problems are located and collected with the aerial views of the cameras. Combined with the GPS to receive the information, an autonomous inspection and airborne image real-time display is presented according to the default track points. It can be used to conduct inspection on ground, relatively small mountain ranges, plains region of daily patrol and large area electric power line disaster monitoring word. The additional features of this paper include current sensor, temperature sensor, camera and GPS tracking for various purposes to monitor the line. Index Terms-Transmission line monitoring system, robot technology, Temperature sensor, GPS tracking. ________________________________________________________________________________________________________ I INTRODUCTION The power generating capacity of our country is very low but conversely the consumption rate is very high as a result of which the demand for power has increased. So it has become necessary to reduce the losses in order to obtain efficient power transmission[1]. In order to achieve this, transmission lines have to be monitored in real time. The simplest form of power lines consists of one conductor per phase hung on insulator string which can be of either suspension or strain type. However in bundled power lines there is more than one conductor per phase. The inspection of power lines are difficult and dangerous for a human to perform due to the nature of their location and also due to the complexity of the power system. In order to rectify this problem, we propose a robot whose purpose is to monitor the transmission lines which would act as an alternative to a human technician. The robot is suspended from the conductor through a roller wheel mechanism and travels along the conductor. In doing so it has to cross the obstacles along the power line that requires complex robotic controls such as conductor grasping, obstacle detection, image processing and pattern recognition which require appropriate sensors, measuring devices, power supply and actuators. By using such an automated system the level of human involvement can be minimized. The robot consists of a current coil (insulation detector), RC servomotors, carbon, rotating shaft, micro-wheel assembly, transmitter, receiver, GPS and a microcontroller unit such as the Arduino. Current coil is used to determine the flow of current through the live transmission lines and the variation in the current coil reading gives the quality of insulation. It is also used to determine the transmission voltage level. Thermal imaging camera is used to measure the temperature of components and this data is used to identify the components that are defective due to normal wear & tear, chemical contamination, corrosion, fatigue and faulty assembly in transmission systems. Over heating can occur in virtually all electrical components including generators, transformers, pole top connections, insulators, jumpers, shoe connections, fuse connections, switch gears and starters. RC servo motors are used for mechanical action of the robot and thus are responsible for the locomotion of the robot. Carbon composite frames which are of low weight, forms the body of the robot. They are of high mechanical & insulating strength. Solar panels provide power to the robot by converting the solar energy into electrical energy. Vibration sensors are used to detect the hissing noise which can occur due to corona effect. In the rotating shaft ultrasonic sensors are used to detect the obstacles of the surroundings and another static sensors on the robot is used to detect the ground clearance to measure the sag in the transmission line. Micro-wheels for the robot movement are fixed over the live conductors. These micro-wheels are connected to the RC servomotors which provide mechanical energy required for the rotating the wheel. GPS assembly and Trans-receiver assembly is used for communicating the position of the robot to the control room and the monitored data. The micro-controller unit integrates all these elements in to a single system [2]. Unlike underground cables, overhead lines are vulnerable to external environmental attacks, such as adverse weather, high humidity, pollution, ground stability, vegetation, and flying objects etc. To ensure high reliability and availability of the overhead lines for bulk electricity transmission, cost effective maintenance strategies including the application of specific accessories and materials, such as lightning arrestor and high voltage insulation coating (HVIC) as well as tower refurbishment to mitigate the risks caused by lightning, pollution and typhoon are essential. Power Corporation has adopted both preventive and condition-based strategies for Transmission overhead line (TOHL) maintenance for many years and has accumulated a lot of valuable experience and knowledge on the implementation of various maintenance and refurbishment practices. These practices have led to the achievement of world class service performance and contributed in the long term economic growth[33. Existing system deals with monitoring of transmission lines by using hot line maintenance. Its main purpose is to inspect transmission lines including conductors, insulators earth wires and poles [4]. This process is done manually by checking each conductors at great height. The inspecting person is placed on the transmission lines by using helicopter. The person on the transmission line have a faraday's suite over him which acts as an insulation between line and person.

International Journal of Advanced Research in Electrical, Electronics and Instrumentation Energy, 2013

Multilevel inverters are used extensively now-a- days due to their increased power rating, improv... more Multilevel inverters are used extensively now-a- days due to their increased power rating, improving harmonic performance and reduced electromagnetic interference. In this paper, an H-bridge inverter topology with reduced number of switches is proposed which produces same number of levels as that of a conventional cascaded multilevel inverter. The proposed system consists of three sources connected in cascade with one source is PV cell and the other two are DC sources. Sinusoidal pulse width modulation technique is used to control the switches of inverter. This technique reduces the complexity of the control circuit, cost and leads to less total harmonic distortion (THD). Proposed novel seven level multilevel inverter with photovoltaic cell topology is validated through simulation using MATLAB/SIMULINK and the results are presented.

the conventional method of converter boost the input voltage but power factor correction cannot b... more the conventional method of converter boost the input voltage but power factor correction cannot be achieved properly in the input side but in the proposed semi bridge less converter boost the input voltage and achieved the power factor correction. The proposed converter features is higher efficiency, eliminate the input ripple. The detailed converter description, steady-state operation and experimental results of both conventional and proposed method are presented and analysed. The converter is applicable for the automotive level I and II but is ideally suitable for level I residential charging application.

International Journal of Advanced Research in Electrical, Electronics and Instrumentation Energy, 2013

This paper presents a three-phase asymmetric cascaded seven level inverter (ACSLI) based Shunt Hy... more This paper presents a three-phase asymmetric cascaded seven level inverter (ACSLI) based Shunt Hybrid Active Power Filter (SHAPF) topology for harmonic reduction in medium voltage test system (MVTS). The proposed SHAF topology consists of ACSLI based shunt active power filter (SAPF) and shunt passive filters (SPF) connected in parallel with the load. The SHAPF topology compensates harmonic currents drawn by non-linear load. The compensation process is based on concept of synchronous reference frame theory (SRFT) used for reference compensation current estimation, carrier switching frequency sub-harmonic pulse width modulation (CSFSHPWM) for generating switching signals for ACSLI, fuzzy logic controller (FLC) for maintaining DC bus capacitor voltage constant. Three types of shunt passive filters namely single tuned, double tuned and high pass filter are used individually for enhancing the harmonic filtering performance of ACSLI based SAPF. The proposed SHAPF topology is validated thr...

International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering, 2015

This paper presents a multilevel inverter that has been conceptualized to reduce component count,... more This paper presents a multilevel inverter that has been conceptualized to reduce component count, particularly for a large number of output levels. It comprises floating input dc sources alternately connected in opposite polarities with one another through power switches. Each input dc level appears in the stepped load voltage either individually or in additive combinations with other input levels. This approach results in reduced number of power switches as compared to classical topologies. The working principle of the proposed topology is demonstrated with the help of a single-phase five-level inverter. The topology is investigated through simulations and validated experimentally on a laboratory prototype. An exhaustive comparison of the proposed topology is made against the classical cascaded H-bridge topology.

This paper presents a novel bidirectional H-Bridge converter to reduce the common mode noise and ... more This paper presents a novel bidirectional H-Bridge converter to reduce the common mode noise and subsequently electromagnetic interference. The proposed H-Bridge converter consists of two switch legs in addition to the available switch legs of a normal H-Bridge converter. It is capable of both unidirectional AC-DC rectification and bidirectional conversion according to the switch operation. The simulation results prove that the proposed circuit has electromagnetic compatibility and low total harmonic distortion shows the reduced common mode noise.

This paper deals With a new family of high boost Voltage inverters that improve upon the conventi... more This paper deals With a new family of high boost Voltage inverters that improve upon the conventional trans-Z-source and trans-quasi-Z-source inverter.[1] The Improved Trans-Z-source Inverter(ITZI) provides continuous input current and a high boost voltage inversion capability. In addition, the improved inverter can suppress resonant Current at startup, which might destroy the device. In comparison to the conventional trans-Z-source/-trans-quasi-z-source inverters, for the same transformer turn ratio and input and output voltages, the improved inverter has a higher modulation index with reduced voltage stress on the dc link,[5] lower current stress flow on the transformer windings and diode, and lower input current ripple. The results are validated by simulating (ITZI) in matlab/simulink.

An interleaved boost converter with zero-voltage switching (ZVS) and zero-current switching (ZCS)... more An interleaved boost converter with zero-voltage switching (ZVS) and zero-current switching (ZCS) characteristics is proposed in this project. With this proposed method in addition to decreasing the current stress of the main circuit device, it can able to ripple of the input current and output voltage. In this launching the soft-switching interleaved converter reduces the complexity and cost. To reduce the switching losses main switches can attain the characteristics of ZVS and ZCS consequently. Based on the condition of the duty cycle this converter topology has two operational conditions, to determine these two conditions a driving circuit is proposed. The principle of operation and designed methods of converter is studied and also theoretical analyzed. Simulations results are used to verify the viability and accuracy of the proposed converter.

Lecture Notes in Electrical Engineering, 2014

ABSTRACT The major power quality issues are voltage sag, voltage swell and voltage harmonics in d... more ABSTRACT The major power quality issues are voltage sag, voltage swell and voltage harmonics in distribution system. These power quality issues are solved by custom power conditioning devices such as Dynamic Voltage Restorer (DVR), Distributed Static Compensator (DSTATCOM) and Unified Power Quality Conditioner (UPQC). This paper presents the ability of Unified Power Quality Conditioner to mitigate voltage sag, voltage swell and voltage harmonics in distribution system. UPQC is modeled in MATLAB_SIMULINK environment with Fuzzy Logic (FL), Neural Network (NN) controllers. The performances of UPQC with two controllers are compared.

International Journal of Software Innovation

In recent years, distributed generations (DGs) are extremely fast in detecting their location, wh... more In recent years, distributed generations (DGs) are extremely fast in detecting their location, which helps to satisfy the ever-increasing power demands. The placement of energy storage systems (ESSs) could be a substantial opportunity to enhance the presentation of radial distribution system (RDS). The major part of DG units in RDS deals with the detection of ideal placement and size of the DGs, which efficiently balance the power loss and voltage stability. The ideal location and size of ESSs are examined in standard IEEE-33 and 69 bus systems, which is important to reduce power losses. Nowadays, several algorithms or techniques are modified for the development of hybrid algorithms to improve the quality of DG allocation. In this research, a hybrid shuffled frog leap algorithm (SFLA) with ant lion optimizer (SFLA-ALO) is proposed for the optimal placement and size of the DG and ESS in the RDS to reduce power losses and maintain the stability of voltage. The performance of the propo...

International Journal of Electrical and Electronics Research

The importance of distributed generation (DG) has increased recently as a result of the growth in... more The importance of distributed generation (DG) has increased recently as a result of the growth in commercial and industrial loads, which has put more pressure on conventional energy sources and utilities. Alternative power generation methods that can handle the massive load without endangering the environment are therefore urgently needed. The installation of Energy Storage Systems (ESSs) may give a substantial opportunity to enhance the aesthetic appeal of the distribution system. DG is a practical substitute for conventional energy sources, which have drawbacks for both the economics and the environment. It goes without saying that there are situations in which a large amount of land and money are required. However, improper DG location or sizing increases safety issues because to the increasing power loss caused by larger reverse flow from the load to the supply. In order to reduce power losses and maintain voltage stability, the ideal location and dimensions for the DG and ESS i...

This paper presents the design of an adaptive power oscillation damping (POD) controller for a st... more This paper presents the design of an adaptive power oscillation damping (POD) controller for a static synchronous compensator (STATCOM) equipped with energy storage. The proposed method is effective in increasing the damping of the system at the desired frequencies. First, the impact of active and reactive power injection into the power system will be carried out using a simple twomachine system model. A control strategy that optimizes active and reactive power injection at various connection points of the STATCOM will be derived using the simplified model. The effectiveness of the proposed control method to provide power oscillation damping irrespective of the connection point of the device and in the presence of system parameter uncertainties will be verified through simulation and results.

The modelling and simulation of modified SVPWM VSI fed three phase Induction motor drive are also... more The modelling and simulation of modified SVPWM VSI fed three phase Induction motor drive are also presented. The drive system is modelled using the blocks of simulink The Z-source inverter is a relatively recent converter topology that exhibits both voltage-buck and voltage-boost capability. The Z-source concept can be applied to all dc-to-ac, ac-to-dc, ac-to-ac, and dc-to-dc power conversion whether two-level or multilevel. Power electronic inverter is a circuit that converts direct power to alternative power. Inverters are commonly used to supply AC power from DC sources such as solar panels or batteries. It is widely used in industrial power conversion systems both for utility and drives applications. Induction motor is popularly used in industries due to ruggedness and robustness. Previous publications have shown the control of a Z-source neutral point clamped inverter using the carrier-based modulation technique. Z-source inverter based adjustable speed drive system (ASD) effec...

This paper discusses the theory and implementation of a class of distributed power converters for... more This paper discusses the theory and implementation of a class of distributed power converters for photovoltaic (PV) energy optimization. Resonant switched-capacitor converters are configured in parallel with strings of PV cells at the sub-module level to improve energy capture in the event of shading or mismatch. The converters operate in a parallel-ladder architecture, enforcing voltage ratios among strings of cells at terminals normally connected to bypass diodes. The balancing function extends from the sub-module level to the entire series string through a dual-core cable and connector. The parallel configuration allows converters to handle only mismatch power and turn off if there is no mismatch in the array. In general the power management architecture can impact the viability of solar energy, increasing energy capture while reducing costs and solving painful integration issues. The central inverter implements a maximum power point tracking (MPPT) algorithm that optimizes power...

EAI Endorsed Transactions on Energy Web, 2022

Power quality enhancement is one of the major concerns from the last few years due to fluctuation... more Power quality enhancement is one of the major concerns from the last few years due to fluctuations occurring in the power transmission and distribution. This paper presents the design of distributed generation system for reducing power quality problems in the distribution system and grid side supply. It involves the design of distributed generation using renewable energy source and also reverse voltage technique based multilevel inverter for integration into the grid. This paper also presents the design of fuzzy controller based modified synchronous rotating frame theory for regulating the DC link voltage and multilevel inverter currents. The system was simulated using MATLAB Simulink and the results are verified with single phase and three phase non linear loads.

This paper proposes a Space Vector Modulation (SVM)-based approach for the switching state redund... more This paper proposes a Space Vector Modulation (SVM)-based approach for the switching state redundancy of an n-level Flying Capacitor Converter(FCC) to carry out the voltage balancing task within the switching states. Capacitor voltage deviations are minimized to choose the proper redundant switching states among the available switching states. The performance of a grid-connected Five-level FCC under the proposed SVM strategy for various operating conditions is simulated and evaluated based on time-domain simulations in the MATLAB/SIMULINK. The simulation results demonstrate the capability of the proposed SVM strategy to regulate the capacitor voltages at their nominal reference values.

This paper deals with a Cuk dc-dc converter as a single-stage power-factor-correction converter f... more This paper deals with a Cuk dc-dc converter as a single-stage power-factor-correction converter for a permanentmagnet (PM) brushless dc motor (PMBLDCM) fed through a diode bridge rectifier from a single-phase ac mains. A three-phase voltage-source inverter is used as an electronic commutator to operate the PMBLDCM driving an air-conditioner compressor. The speed of the compressor is controlled to achieve optimum airconditioning using a concept of the voltage control at dc link proportional to the desired speed of the PMBLDCM. The stator currents of the PMBLDCM during step change in the reference speed are controlled within the specified limits by an addition of a rate limiter in the reference dc link voltage. The proposed PMBLDCM drive (PMBLDCMD) is designed and modeled, and its performance is evaluated in Matlab-Simulink environment. Simulated results are presented to demonstrate an improved power quality at ac mains of the PMBLDCMD system in a wide range of speed and input ac volt...

This paper discusses the design of a new transformerless single-stage single-switch double buck c... more This paper discusses the design of a new transformerless single-stage single-switch double buck converter (ISSSSDB) which integrates a buck-type power factor correction (PFC) cell with a buck-type dc–dc output cell in a special way. High input power factor can be obtained automatically by operating the PFC cell inductor in discontinuous conduction mode (DCM), where the well and tight output voltage is regulated by the DC-DC cell. The advantages of this converter are low voltage stress across the dc-link capacitor, low current stress on the switch, and high step down input to output voltage, low cost and reduced size. These characteristics makes the converter costefficient, easy-to-design, and suitable for the low-power and non-isolated applications. The results are validated by simulating ISSSSDB using MATLAB/Simulink.

Journal of emerging technologies and innovative research, 2018

B. Ravi teja, Dr. G. Jayakrishna,Akhib Khan Bahamani Assistant professor, Professor, Assoc.Profes... more B. Ravi teja, Dr. G. Jayakrishna,Akhib Khan Bahamani Assistant professor, Professor, Assoc.Professor Electrical & Electronics Engineering, Narayana Engineering College, Nellore, India ________________________________________________________________________________________________________ Abstract : This paper is designed in such a way that it overcomes this limitation by the use of solar energy. Hybrid Inverter with Solar Battery Charging System consists of an inverter powered by a 12V Battery. This inverter generates up to 230V AC with the help of driver circuitry and a heavy load transformer. This battery gets charged from two sources, first being the mains power supply itself and second from the solar power. If the mains power supply is available, then the relay switches to main power supply for supplying the load. This power supply also charges the battery for using it as back up the next time when there is a power outage. The use of solar panel to charge the battery gives an ad...

International journal of engineering research and technology, 2014

This paper presents a low cost single phase inverter with virtual DC bus for common mode ground l... more This paper presents a low cost single phase inverter with virtual DC bus for common mode ground leakage current elimination in PV systems. It concentrates on the removal of common mode ground currents in the transformer less PV systems using virtual DC bus concept. In addition to this, the virtual Dc bus provides a negative voltage level for the generation of negative ac grid current. Based on this idea, an inverter topology is designed, in which the virtual DC bus is created with the switched capacitor technology. It uses two switched capacitors, five power switches and only a single filter inductor, which results in reduced cost of the device. This inverter topology is modulated with two techniques such as unipolar sinusoidal pulse width modulation (UPSPWM) and double frequency sinusoidal pulse width modulation (DFSPWM) for a DC input of 400V from the PV panels. Simulated results concluded that the proposed inverter topology provides the reduced output current ripple, low THD and ...

Journal of emerging technologies and innovative research, 2018

In the field of Electrical Engineering, the transmission line plays an important role. During the... more In the field of Electrical Engineering, the transmission line plays an important role. During the transmission of electricity some faults occur in it. The main problems faced by transmission lines are damage of insulators, conductor corrosion, vibration damage, arching damage of conductors and leakage of current. Many lines are located in remote and rugged environments. Usually the workers who inspect these lines conduct the helicopter surveys or must climb the tower to check the line close proximity. In connection with the shortcomings of the current power transmission line inspection Transmission Line Monitoring System(TLMS) or Robot technology, a new electric power inspection leading to significant cost benefits in contrast to the conventional systems(Helicopters, industrial climbers etc.) is developed to improve the monitoring and control. The images of the line defects and potential problems are located and collected with the aerial views of the cameras. Combined with the GPS to receive the information, an autonomous inspection and airborne image real-time display is presented according to the default track points. It can be used to conduct inspection on ground, relatively small mountain ranges, plains region of daily patrol and large area electric power line disaster monitoring word. The additional features of this paper include current sensor, temperature sensor, camera and GPS tracking for various purposes to monitor the line. Index Terms-Transmission line monitoring system, robot technology, Temperature sensor, GPS tracking. ________________________________________________________________________________________________________ I INTRODUCTION The power generating capacity of our country is very low but conversely the consumption rate is very high as a result of which the demand for power has increased. So it has become necessary to reduce the losses in order to obtain efficient power transmission[1]. In order to achieve this, transmission lines have to be monitored in real time. The simplest form of power lines consists of one conductor per phase hung on insulator string which can be of either suspension or strain type. However in bundled power lines there is more than one conductor per phase. The inspection of power lines are difficult and dangerous for a human to perform due to the nature of their location and also due to the complexity of the power system. In order to rectify this problem, we propose a robot whose purpose is to monitor the transmission lines which would act as an alternative to a human technician. The robot is suspended from the conductor through a roller wheel mechanism and travels along the conductor. In doing so it has to cross the obstacles along the power line that requires complex robotic controls such as conductor grasping, obstacle detection, image processing and pattern recognition which require appropriate sensors, measuring devices, power supply and actuators. By using such an automated system the level of human involvement can be minimized. The robot consists of a current coil (insulation detector), RC servomotors, carbon, rotating shaft, micro-wheel assembly, transmitter, receiver, GPS and a microcontroller unit such as the Arduino. Current coil is used to determine the flow of current through the live transmission lines and the variation in the current coil reading gives the quality of insulation. It is also used to determine the transmission voltage level. Thermal imaging camera is used to measure the temperature of components and this data is used to identify the components that are defective due to normal wear & tear, chemical contamination, corrosion, fatigue and faulty assembly in transmission systems. Over heating can occur in virtually all electrical components including generators, transformers, pole top connections, insulators, jumpers, shoe connections, fuse connections, switch gears and starters. RC servo motors are used for mechanical action of the robot and thus are responsible for the locomotion of the robot. Carbon composite frames which are of low weight, forms the body of the robot. They are of high mechanical & insulating strength. Solar panels provide power to the robot by converting the solar energy into electrical energy. Vibration sensors are used to detect the hissing noise which can occur due to corona effect. In the rotating shaft ultrasonic sensors are used to detect the obstacles of the surroundings and another static sensors on the robot is used to detect the ground clearance to measure the sag in the transmission line. Micro-wheels for the robot movement are fixed over the live conductors. These micro-wheels are connected to the RC servomotors which provide mechanical energy required for the rotating the wheel. GPS assembly and Trans-receiver assembly is used for communicating the position of the robot to the control room and the monitored data. The micro-controller unit integrates all these elements in to a single system [2]. Unlike underground cables, overhead lines are vulnerable to external environmental attacks, such as adverse weather, high humidity, pollution, ground stability, vegetation, and flying objects etc. To ensure high reliability and availability of the overhead lines for bulk electricity transmission, cost effective maintenance strategies including the application of specific accessories and materials, such as lightning arrestor and high voltage insulation coating (HVIC) as well as tower refurbishment to mitigate the risks caused by lightning, pollution and typhoon are essential. Power Corporation has adopted both preventive and condition-based strategies for Transmission overhead line (TOHL) maintenance for many years and has accumulated a lot of valuable experience and knowledge on the implementation of various maintenance and refurbishment practices. These practices have led to the achievement of world class service performance and contributed in the long term economic growth[33. Existing system deals with monitoring of transmission lines by using hot line maintenance. Its main purpose is to inspect transmission lines including conductors, insulators earth wires and poles [4]. This process is done manually by checking each conductors at great height. The inspecting person is placed on the transmission lines by using helicopter. The person on the transmission line have a faraday's suite over him which acts as an insulation between line and person.

International Journal of Advanced Research in Electrical, Electronics and Instrumentation Energy, 2013

Multilevel inverters are used extensively now-a- days due to their increased power rating, improv... more Multilevel inverters are used extensively now-a- days due to their increased power rating, improving harmonic performance and reduced electromagnetic interference. In this paper, an H-bridge inverter topology with reduced number of switches is proposed which produces same number of levels as that of a conventional cascaded multilevel inverter. The proposed system consists of three sources connected in cascade with one source is PV cell and the other two are DC sources. Sinusoidal pulse width modulation technique is used to control the switches of inverter. This technique reduces the complexity of the control circuit, cost and leads to less total harmonic distortion (THD). Proposed novel seven level multilevel inverter with photovoltaic cell topology is validated through simulation using MATLAB/SIMULINK and the results are presented.

the conventional method of converter boost the input voltage but power factor correction cannot b... more the conventional method of converter boost the input voltage but power factor correction cannot be achieved properly in the input side but in the proposed semi bridge less converter boost the input voltage and achieved the power factor correction. The proposed converter features is higher efficiency, eliminate the input ripple. The detailed converter description, steady-state operation and experimental results of both conventional and proposed method are presented and analysed. The converter is applicable for the automotive level I and II but is ideally suitable for level I residential charging application.

International Journal of Advanced Research in Electrical, Electronics and Instrumentation Energy, 2013

This paper presents a three-phase asymmetric cascaded seven level inverter (ACSLI) based Shunt Hy... more This paper presents a three-phase asymmetric cascaded seven level inverter (ACSLI) based Shunt Hybrid Active Power Filter (SHAPF) topology for harmonic reduction in medium voltage test system (MVTS). The proposed SHAF topology consists of ACSLI based shunt active power filter (SAPF) and shunt passive filters (SPF) connected in parallel with the load. The SHAPF topology compensates harmonic currents drawn by non-linear load. The compensation process is based on concept of synchronous reference frame theory (SRFT) used for reference compensation current estimation, carrier switching frequency sub-harmonic pulse width modulation (CSFSHPWM) for generating switching signals for ACSLI, fuzzy logic controller (FLC) for maintaining DC bus capacitor voltage constant. Three types of shunt passive filters namely single tuned, double tuned and high pass filter are used individually for enhancing the harmonic filtering performance of ACSLI based SAPF. The proposed SHAPF topology is validated thr...

International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering, 2015

This paper presents a multilevel inverter that has been conceptualized to reduce component count,... more This paper presents a multilevel inverter that has been conceptualized to reduce component count, particularly for a large number of output levels. It comprises floating input dc sources alternately connected in opposite polarities with one another through power switches. Each input dc level appears in the stepped load voltage either individually or in additive combinations with other input levels. This approach results in reduced number of power switches as compared to classical topologies. The working principle of the proposed topology is demonstrated with the help of a single-phase five-level inverter. The topology is investigated through simulations and validated experimentally on a laboratory prototype. An exhaustive comparison of the proposed topology is made against the classical cascaded H-bridge topology.

This paper presents a novel bidirectional H-Bridge converter to reduce the common mode noise and ... more This paper presents a novel bidirectional H-Bridge converter to reduce the common mode noise and subsequently electromagnetic interference. The proposed H-Bridge converter consists of two switch legs in addition to the available switch legs of a normal H-Bridge converter. It is capable of both unidirectional AC-DC rectification and bidirectional conversion according to the switch operation. The simulation results prove that the proposed circuit has electromagnetic compatibility and low total harmonic distortion shows the reduced common mode noise.

This paper deals With a new family of high boost Voltage inverters that improve upon the conventi... more This paper deals With a new family of high boost Voltage inverters that improve upon the conventional trans-Z-source and trans-quasi-Z-source inverter.[1] The Improved Trans-Z-source Inverter(ITZI) provides continuous input current and a high boost voltage inversion capability. In addition, the improved inverter can suppress resonant Current at startup, which might destroy the device. In comparison to the conventional trans-Z-source/-trans-quasi-z-source inverters, for the same transformer turn ratio and input and output voltages, the improved inverter has a higher modulation index with reduced voltage stress on the dc link,[5] lower current stress flow on the transformer windings and diode, and lower input current ripple. The results are validated by simulating (ITZI) in matlab/simulink.

An interleaved boost converter with zero-voltage switching (ZVS) and zero-current switching (ZCS)... more An interleaved boost converter with zero-voltage switching (ZVS) and zero-current switching (ZCS) characteristics is proposed in this project. With this proposed method in addition to decreasing the current stress of the main circuit device, it can able to ripple of the input current and output voltage. In this launching the soft-switching interleaved converter reduces the complexity and cost. To reduce the switching losses main switches can attain the characteristics of ZVS and ZCS consequently. Based on the condition of the duty cycle this converter topology has two operational conditions, to determine these two conditions a driving circuit is proposed. The principle of operation and designed methods of converter is studied and also theoretical analyzed. Simulations results are used to verify the viability and accuracy of the proposed converter.