Power Electronics and Drives

In this paper, the issues of Electro Magnetic Interference (EMI) and its suppression in a Power Electronic System is presented. Different noises especially common mode noise and differential mode noise are analysed. A Boost PFC circuit employing ZVT technique is analysed and then an EMI filter is designed in the input side of PFC converter to protect the converter from

A new four quadrant Field Orientation-Controlled (FOC) three-phase induction motor drive based on Hysteresis Current Comparison (HCC) has been developed. The direct relationship between current and torque in the Direct-Quadrature (dq) reference frames has been exploited to develop an HCC scheme that offers accurate tracking of current and torque based on the pulse width modulation technique. The parameters of the inner HCC and the outer Proportional-Integral (PI) speed controllers have been optimised to obtain effective current and torque tracking. The complete closed loop system being speed-controlled, four quadrant operation has been obtained using step speed input while the suitability of the developed model has been tested under full load stress during steady state. The results obtained satisfy the four quadrant operation requirements of advanced drives where controlled starts and stops are essential in both forward and reverse directions. This is evident in the effectiveness of current and torque tracking and ease of speed transition from motoring to regeneration and vice versa. The developed model finds applications in advanced industrial drives as an energy-efficient and cost-effective alternative to eliminate the effects of supply voltage drops and mechanical load variations.

In this paper, the experiments on phosphor-converted LEDs (pc-LEDs) with a correlated color temperature (CCT) of 8500K has been conducted with
the scattering enhancement particles (SEPs) to achieve the higher color uniformity and emitted luminous flux of pc-LEDs. Moreover, this paper also introduced about choosing scattering enhancement particles (SEPs), including calcium carbonate (CaCO3) and titania (TiO2), and compared these particles’ properties by adding them into the yellow Y3Al5O12:Ce3+ phosphor compounding. Afterward, the LightTools program was applied to illustrate the optical simulation, and obtained results was analyzed and verified by applying the Mie-scattering theory. The scattering coefficients, the anisotropic scattering, the reduced scattering, and the scattering amplitudes at 455 nm and 595 nm are included in the scattering computation of SEPs. According to researched results, among the SEPs, TiO2 particles result in the highest value of color uniformity. However, a rise in their concentration is the cause of a sharp decline in luminous flux. Meanwhile, CaCO3 particles show the ability of reducing the deviated level in correlated color temperature by 620K if there is employed 30% of CaCO3 concentration. Hence, CaCO3 particles are the recommendation for achieving higher chromatic homogeneity and lumen output.

Among conformal phosphor structure, in-cup phosphor structure, and remote phosphor structure, while in term of attaining the highest luminous flux, remote phosphor structure is the most ideal one, it seems to be that this structure results in the lowest-quality of color. Therefore, it is necessary in conducting experiments to surmount this disadvantage and make a possibility in enhancing the color quality of WLEDs with remote phosphor structure. In this research, with the ability of advancing the color rendering index (CRI) and color quality (CQS) for WLEDs, a dual-layer remote phosphor structure was considered as a suggestion. The experiments in this study used three kinds of WLEDs with the similar structures but different color temperatures varying at 5600 K, 7000 K, and 8500 K. The objectives of this paper is proposing a solution to obtain the highest color quality by placing a yellow-green emitting SrBaSiO4:Eu 2+ phosphor layer or a red-emitting SrwFxByOz:Eu 2+ ,Sm 2+ phosphor layer on the YAG:Ce 3+ phosphor layer and then choosing the most appropriate value of SrwFxByOz:Eu 2+ ,Sm 2+ concentration. The experimental results which are satisfied expectations of researchers indicated that SrwFxByOz:Eu 2+ ,Sm 2+ has enforced its role in managing to raise the CRI and CQS. Particularly, the greater concentration of SrwFxByOz:Eu 2+ ,Sm 2+ leads to the higher the CRI and CQS, since the red light component in WLEDs increased. Besides, the quality of luminous flux is in a tight connection with the SrBaSiO4:Eu 2+ phosphor layer. Whereas, according to the Mie scattering theory and the Lambert-Beer law, if the concentration of SrwFxByOz:Eu 2+ ,Sm 2+ and SrBaSiO4:Eu 2+ becomes redundant, the luminous flux and color quality will take a deep dive. Briefly, the results from this article has largely contributed to fabricating high-quality WLEDs.

This paper studies the use of power electronic drives to implement dynamic thermal inertia control in low-energy buildings. Dynamic management of energy components is used to offset variability of stochastic solar resources. Emphasis is on power electronic HVAC (heating, ventilation, and air conditioning) drives, which can act as an effective electric swing bus to mitigate solar power variability. In doing so, grid power flows become substantially more constant, reducing the need for fast grid resources or dedicated energy storage such as batteries. The concept is equivalent to using building thermal energy as virtual dynamic storage in support of power grid operation. The paper defines a bandwidth over which such HVAC drives can operate. To test the methods, 18 months of solar data have been collected on sub-millisecond time scales as a basis to evaluate efficacy, determine solar frequency-domain content, and analyze mitigation of variability. A practical band-pass filter is realized with a lower frequency bound such that the building maintains consistent temperature, and an upper frequency bound to ensure that commanded HVAC fan speeds do not update arbitrarily fast, avoid acoustic discomfort to occupants, and prevent undue hardware wear and tear. The combination is illustrated in simulation and with experimental results based on various update rates of a variable frequency fan drive over stochastic solar data. Building electrical and thermal energy systems modeling is addressed, including solar and HVAC systems as well as batteries and large-scale thermal storage. A full-scale multiple-day case study provides insight on potential grid-side and storage-related benefits.

This paper introduces various electrical and thermal energy generation, consumption, and storage components in solar powered low-energy buildings. Dynamic management of such energy components is essential given the stochastic solar resources. Emphasis is put on power electronic HVAC (heating, ventilation, and airconditioning) drives, which can act as an effective electric swing bus to mitigate solar power variability. In doing so, grid power flows become substantially more constant, reducing the need for fast grid resources or dedicated energy storage such as batteries. The concept is equivalent to using building thermal energy as virtual dynamic storage in support of power grid operation. The paper defines a bandwidth over which such HVAC drives can operate. A practical band-pass filter is realized that provides 1) lower frequency bounds such that the building maintains consistent room temperature via the HVAC system as demonstrated by a thermal modeling study, and 2) upper frequency bounds that ensure commanded HVAC fan speeds do not update arbitrarily fast. The latter primarily avoids acoustic discomfort to users. The combination is illustrated by experimental results based on various update rates of a variable frequency fan drive over a sample of actual stochastic solar data. Building electrical and thermal energy systems modeling by MATLAB is addressed throughout the paper, including solar and HVAC systems as well as batteries and water tanks. Index Terms—Low-energy buildings, frequency domain analysis, grid-level energy storage, HVAC systems, solar energy, thermal storage, power electronic drives, complex system energy management

The Brushless dc motor is a simple and robust machine, which has found application over a wide power and speed ranges in different shapes and geometries. This paper presents a new configuration for an integrated starter-generator system based on brushless dc motor without permanent magnet technology. The proposed novel motor consists of two magnetically dependent stator and rotor sets (layers), where each stator set includes nine salient poles with windings wrapped around them while, the rotor comprises of six salient poles with no windings. The magnetic field passes through a guide to the rotor then the stator and finally completes its path via the motor housing. To evaluate the motor performance, two types of analysis, namely numerical technique and experimental study have been utilized. In the numerical analysis the finite element analysis is employed, where as in the experimental study, a proto-type motor has been built and tested. The calculated results compare favorably with the test results. Due to the ruggedness of the proposed motor in comparison with the conventional and brushless dc motors it looks very promising for hybrid vehicle.

Rapid depletion of fossil fuel reserves, and concerns over climate change have encouraged power generation from sustainable energy based microgrids. And to address the necessity of three-phase inverters in microgrid systems or sustainable-powered households, an Arduino-based three-phase inverter using MOSFET is designed, which converts DC into three-phase AC power. The designed system generates 223V square signals at each phase from a 12V battery through switching of three stages of power MOSFETs using pulse width modulation (PWM) signals at their gates from an Arduino Uno. Each stage of power MOSFETs consists of six transistors making it eighteen in total, which are used to perform the inversion process separately for each three single-phase connections. The system is programmed using an Arduino Uno to generate PWM signals and to keep 120 degrees phase displacement among each phase. Three step-up transformers are coupled at the outputs of MOSFET stages for amplification. The system...

Cascaded H-bridge Multilevel Inverter (CHBMLI) is the most suitable topology for the PV power converters. In this paper an effort has been made to increase the performance of CHBMLI by improving the fundamental Root Mean Square (RMS) value of the output voltage. This work proposes a Modified Multi Carrier PWM (MMCPWM) technique where, reference sine wave has been replaced by ellipse wave, resulting in enhanced performances on the fundamental rms output voltage and lower Total Harmonic Distortion (THD). Analysis of single phase 5-level CHBMLI with and without load are carried for the different Multi Carrier PWM (MCPWM) techniques. Results were compared for both MCPWM and MMCPWM at different modulation indices. The proposed MMCPWM technique emerged as a very promising technique in enhancing the fundamental output voltage and at the same time mitigating the problem of THD. 5-level CHBMLI with the proposed control strategy is simulated in MATLAB/SIMULINK. The results were compared with the existing literature for validation of the proposed control strategy.

Hybrid energy systems are increasingly being applied in areas where grid extension is considered uneconomical. Their costs can be minimized through proper equipment sizing and load matching. This paper reports the results of optimization of hybrid energy system model for remote area in India. For this purpose, the Jaunpur block of Uttaranchal state of India has been selected as remote area. The model is developed with the objective of minimizing cost function based on demand and potential constraints. The model has been optimized using LINDO software 6.10 version. From the economic analysis, the capital cost, cost of energy for different types of resources, optimized cost of hybrid energy system are determined. In order to consider the fluctuation in the discharge and power generation from SHP, the EPDF has been varied from 1.0 to 0.0. The EPDF is electric power delivery factor and also called optimizing power factor and is maximum equal tol.

There is so many applications in which the cells must be used in series to form a battery pack. When a group of cells are arranged to form a battery pack the voltage across individual cells must be equal at all times. Otherwise the battery life gets reduced as the change in voltage level in any one cell will adversely affects other cells. This paper aims to introduce a new technology of equalizing the voltage across individual cells in a battery pack at every instant. The basic element in this technology is the CUK-converter, which is a DC-DC converter.CUK is a switched mode control and this switching is established with the help of microcontroller which manipulates the signals from each cells to form gate signals for driving converter MOSFETs. The greatest advantage of this technique is that as CUK converter is used the power lost in this technique will be minimum because CUK converters has got efficiency of more than 95%.The paper presents basic principles and theoretical analysis of CUK converter action, control strategy that is to be adopted for the equalization scheme. The P-Spice analysis of converter, few experimental waveforms etc.are also included in this paper.

A novel anti-sway control system for cranes is proposed. The proposed method is based on theformation of a predetermined sway angle as a piecewise-continuous function, the second derivative of which doesnot experience discontinuity. Its third derivative is a rectangular pulse of certain variable-sign amplitude, whichresults in eliminating the mechanical stress in the crane construction and kinematic gears. A comprehensivemathematical model and an experimental prototype of the crane are developed. Simulation and experimentalresults prove that the proposed anti-sway method enables damping of the oscillations of the suspended load duringits horizontal motion (in two orthogonal coordinates) and hoisting/lowering. The control method is invariant to themechanism/load mass ratio, lift height and hoisting speed.

In this paper are presented the power losses and sources of their occurrence in worm gear boxes. These are the losses that occur in the coupling of worm teeth and worm gear, losses in bearings, seals and oil churning power losses in the transmission. When the operation of worm gearing is characterized by line contact of coupled elements which is accompanied by significant sliding, the highest value have the power losses in the worm and worm gear coupling compared to other losses in gearing. Among other things, in the paper also presents the expressions that are used for calculation of individual power losses and efficiency of the gearing. The size of the losses primarily depends on the type of coupled material and geometry of worm pair, circumferential velocity (input rotational speed), the type and viscosity of lubricating oil, load, worm shape, and temperature and so on. The paper also deals with the influence of different factors on power losses and efficiency. As the efficiency of the worm pair is significantly lower compared to other types of gear pairs, the appropriate combination of geometric parameters and materials of worm and worm gear, lubrication and working conditions can significantly affect its increase.

In constant V/f control technique it is assume that the stator resistance and leakage inductance drops are negligible, especially at high speed and small load. In other words, the back emf is comparatively large at high speed and hence these voltage drops can be neglected. By maintaining constant V/f, constant Eg/f and hence constant air-gap flux is assumed. This assumption is however invalid at low speeds since a significant voltage drop appears across the stator impedance. The terminal voltage, V no longer approximates  ag. By using MATLAB Simulink, the open-loop constant V/f is simulated. It is shown that the performance of the drive deteriorates at low speeds. The improvement in the performance by applying voltage boost is shown and discussed.

To address the requirement for three-phase inverters in microgrid systems or sustainable-powered industrial facilities, a MOSFET-based three-phase inverter is designed and implemented, which can convert DC power into three-phase AC. The designed system produces 223V square (AC) waves at each phase from a 12V battery (DC) through switching of three stages of power MOSFETs using PWM signals at their gates from an Arduino Uno R3. Each stage of MOSFETs consists of six MOSFETs making it eighteen in total, which are used to perform the inversion process separately for each of three single-phase connections. The system is programmed through the Arduino Uno to generate the PWM signals and to keep 120 degrees phase displacement among each phase. Three center-tapped step-up transformers are used at the outputs of MOSFET stages for signal amplification. Using a 60W incandescent light bulb at each phase as a load, the system produces 386.2SV of voltage for three-phase line, delivering 0.58A of ...

This doctoral thesis represents a set of new ideas, methods and research re-sults related to improving the efficiency of functioning of ship power plants (SPP) of combined propulsion complexes (CPC). The main motivation for these studies is the existing current practice requests for the operation of the SPP CPC, such as: ensuring minimization of irreversible losses in the transmission of capac-ities from the SPP to the engines of the CPC; the need to improve the monitoring of the transfer of capacities in the SPP CPC with dynamic principles of retaining the vessel; increasing the operational reliability and strength of the SPP CPC; creation of new and improvement of existing decision support systems (DSS) during operation, research and design of the SPP CPC.
Based on the analysis of the existing state of the development of the SPP CPC, the following unresolved problems were found on the lines of propellers, in power systems of motors for thrusters and power distribution systems, which can be characterized as follows: reduction of propeller thrust and torque due to water flow perpendicular to the axis of the propeller caused by the flow from the vessel speed or flows from other engines with force in the direction of inflow due to the deflection of the propeller flow. This is often called a cross-combination of resistances; the presence of cavitation for heavy loads on the propellers leads to a reduction in pressure on the blade of the propeller and can occur during a small immersion of the propeller due to the movement of the ship across the waves; sudden drops of thrust and torque with the effect of hysteresis due to the large amplitude of the ship's motion perpendicular to the surface of the water; simulta-neous reduction of thrust and change of thrust direction due to interaction of the flow from the thruster to the hull (Coanda effect); loss of the thrust and reduction of thrust caused by the action of the propellant flow from one motor to adjacent motors; limitation of the increase in torque by the inductance of the motor with the prevention of damage to the mechanical part of the electric drive; limitation of the maximum power of the thruster, is taken into account when determining the overload capacity of the electric motor and frequency converter (FC); the absence of a control strategy for the thruster FC based on  variable speed governors which provide the transition of consumers, working on a constant power hyper-bola, to the torque or speed of rotation control mode; the need for Dynamic Posi-tioning (DP) systems to meet the quality management requirements encountered during the operational phase; unification of Power Management System (PMS) in a combination of functions in relation to others similar; the independence of PMS systems components from each other to the level of sensors; not only the reduc-tion in capacity based on the total design load, but also the load of an individual medium speed diesel generator (MSDG); compliance of the system with condi-tions increasing the load in terms of sufficiency to ensure normal operation in re-lation to any abnormal mode and non-overloading the ship electric power system (SEPS) in general.
The above problems directly led to the formulation of the main complex re-search task: the development of a DSS for the design, research and improvement of SPP CPC, consisting of three main tasks: the development of a monitoring system for degradation effects on the lines of propulsion flows of motors with the identification of relevant markers, the development of the strategy for all-mode power controllers, torque controllers and variable speed governors by the electric motors of the CPC thrusters and the development of the methodology for con-structing multi-criteria control strategies over power distribution of the SPP CPC.
As a result of solving the main and auxiliary tasks, the following scientific positions were obtained: improvement of the method of computational hydrody-namics is provided by using the distribution of the sought-for intensities of the degradation effects from the interaction of the propeller flows among themselves and the CPC body due to the use of piezoelectric sensors on the shaft lines of az-imuth thruster. Compensation of degradation effects is achieved by calculation of power flows from azimuth thrusters in the form of a power drive disc, which al-lows identifying turbulent regions with relative vortex viscosity coefficients μt/μw. Calculation of the components of the x-velocities at the intersection of the propel-ler flow along the axis of rotation with dimensions in units of the diameter of the DP propeller makes it possible to realize the method of surface-oriented averag-ing of the Reynolds-Navier-Stokes equation for mass transfer at the interface; limitations on power and torque on the shaft lines of the SPP CPC thruster of dynamically positioning vessels are provided by redistribution of the thrusts be-tween the thrusters or the reduction of the maximum load as part of the algo-rithm for distributing the thrust of the DP system due to the application of the strategy of full range speed governors in relation to operating conditions; for the first time, a three-level multi-criteria strategy for managing the distribution of en-ergy in the hybrid SPP CPC was developed by integrating the classical strategy of power distribution management with a strategy of control over the state of the MSDG and the degree of charge of the energy storage system alternative generat-ing element. The developed strategy differs from existing by higher speed detec-tion of risk of de-energization of ship electric power system, greater reliability and accuracy in determining the need for load reduction and the thruster speed of rotation fully integrated with variable speed governors and power supply system; for the first time, the DSS was created to study the ways of automating and com-puterizing the design and operation processes of the SPP CPC, which being based on theoretical, design and experimental methods, has enabled the introduction of a comprehensive substantiation, verification and self-testing of the developed components of the methodological and mathematical apparatus; for the first time, a physical model of a multifunctional CPC with a variable structure was created, which, in synergy with the solution of the problem of DSS development, allows iterative analysis of the structures of the SPP CPC with minimal initial data; the law of pulsations of thrusts on the lines of propeller shafts is established, which occur under conditions of interaction of several thrusters with each other and with the CPC body. In the process of studying the version of the configuration of a CPC with contra-rotating propellers (CRP) it was established that: 1) the rota-tion of the thruster body leads to the appearance of characteristic recirculation zones and changes in the velocity fields in its disk and differs by an increased de-gree of flow heterogeneity; 2) the characteristics of the thrust and the torque of the thruster differ significantly depending on the direction of rotation; 3) the pul-sation of the propeller thrust  of the azimuth thruster sharply increases with its rotation, and the most significant growth in pulsations occurs at the resonant fre-quencies of the interaction of the propeller flow of the azimuth thruster and the stationary one; the theory of non-stationary interaction of several propellers with each other has been developed, which made it possible to establish for the first time the following facts: 1) rotation of the thruster  leads to an increase in the ax-ial and tangential components of the thrusts and torques; 2) the operation of the azimuth thruster at large angles with respect to the stationary propeller results in the appearance of significant loads on the  thruster stock, which can be determi-native in terms of the strength of the structural components of the thruster, the presence of deformations of which has been experimentally established and con-firmed by calculation. Also, for the first time, the dependencies of the thrusts and torques of the azimuth thruster were determined as a result of the interaction of the propeller flow with the hull and the stock due to the occurrence of degrada-tion effects; for the first time, a simplified semi-empirical method for iterative progressively regressive parameterization of the SPP CPC was developed in off-design operation modes, which generalizes the previously relationship, which have been derived for thrusts and torques of co-axial CPP s in a homogeneous flow with ratios known from the theory of turbomachines for the case of interac-tion between the stationary propeller and the azimuth thruster. On the basis of this technique, a calculation method has been developed that makes it possible to accurately estimate the value of thrusts and torques of motors for azimuth thrust-ers in a wide range of operating conditions and the angles of flow deflection due to the influence of degradation effects that are substantially different from the de-sign ones. The necessity to take into account the influence of degradation effects on the lines of propeller shafts in the CRP Azipod® concept has been proved

This paper presents dynamic analysis of a boost type DC-DC converter for high-brightness LED (HBLED) driving applications. The steady state operation in presence of all system parasitics has been discussed for continuous conduction mode (CCM). The state-space averaging, energy conservation principle and standard linearization are used to derive ac small signal control to inductor current open-loop transfer function of the converter. The derived transfer function can be further used in designing a robust feedback control network for the system. In the end frequency and transient responses of the derived transfer function are obtained for a given set of component values, hence to provide a useful guide for control design engineers.

Power electronics converters are widely used in power system such as motor drive applications because of their low cost and higher reliability. Rectifiers are used whenever AC to DC conversion is needed. 12-pulse controlled scheme is the basic topology of rectifier mainly used in high voltage DC transmission system and many other applications. This type of converter can operate reducing certain line current harmonics.
It is needed to understand the performance of this converter qualitatively and their impacts on power system due to their harmonics. Therefore, it is necessary to predict the harmonic levels of converter. By using 12-pulse rectifiers in AC to DC conversion, power factor will improve and total harmonic distortion can be reduced compared with simple diode and thyristor bridge rectifiers. In this paper, both input and output sides of 12-pulse rectifier with highly inductive RL load is analyzed and MatLab SimuLink will be used to simulate all necessary waveforms and to get required information.

Vector control of AC motor developed by K. Hasse and F. Blaschke introduces a new technology in industrial drives in 1968 and in early 1970s.Induction motors are the most widely used electric motors due to its reliability, low cost ,low maintaince, less weight and robustness however induction motor do not inherently have the capability of fast dynamic performance due to coupling nature. Due to this reason earlier D.C.Motors were applied in most electrical drives though it is high cost, not reliable, high weight ,high maintaince but the recent development in vector control of Induction motor have lead to their large scale use in almost all electrical drive. In vector control method machine is control in a synchronously rotating frame where as in sinusoidal machine variables appears as D.C. quantities. In steady state current resolved in to two control inputs I. e. direct axis and quadrature axis component in a synchronously rotating reference frame, direct axis component act as field current and quadrature axis component act as armature current just like in D.C.Motors. For vector control direct axis components must oriented in the direction of rotor flux and quadrature axis components must perpendicular to it under all operating conditions .So vector control must ensure correct orientation of the space vector and generate control import signal. This develops closed loop control system .So that we can independently control flux & torque which provides fast dynamic performance like D.C.Motors.

Modern AC drives are designed mostly around an induction motor. An induction motor is operated through inverter, which converts a DC voltage to an AC voltage. In MOSFET inverters the gate voltage of the MOSFET is changed by a Pulse Width Modulated (PWM) signal to produce an AC voltage from a DC input. In this paper a microprocessor-based system is described which produces Sinusoidal Pulse Width Modulated (SPWM) signal that can be used for controlling the inverters of a single-phase induction motor. Here a variety of PWM patterns are stored in a Look Up Table (LUT) in a ROM from which the appropriate pattern is generated according to the desired frequency and modulation index (M). This system may readily be extended for a three-phase motor.

— This paper deals with the exposition of how robotics can be applied to various fields of agriculture. One of the most important occupations in a developing country like India is agriculture. It is very important to improve the efficiency and productivity of agriculture by replacing laborers with intelligent machines like robots using latest technologies. The paper proposes a new strategy to replace humans in various agricultural operations like detection of presence of pests, spraying of pesticides, spraying of fertilizers etc there by providing safety to the farmers and precision agriculture. The developed system involves designing a prototype which uses simple cost effective equipments like microprocessor, wireless camera, various motors and terminal equipments which is an aid to the farmers in various crop field activities.

Vibratory screens are machines that, when subjected to the mechanical vibration, carry out the separation of material mixtures to granulation, or to fractions. The number of fractions depends on the number of storeys on a vibrating screen. This paper discusses the regulated electric drive of vibratory screens with one storey, used to separate the boiler ash from the slag (bottom ash) in the Thermal Power Plants TENT-B, Obrenovac. Some of the important parameters of vibratory sieving are frequency and amplitude of vibrations, tilt angle of the vibratory screens, and the angle of the actuating force acts on the vibrating screen. The proposed technical solution is provided to adjust all of these parameters. The synchronous operation of vibratory exciters is requested, as well as the work of vibratory screens in super-resonant mode. The paper presents the experimental results and determining the amplitude-frequency (AF) characteristics of the vibrating screens.

Direct torque control (DTC) is one of the most excellent control strategies of torque control in induction motor. The aim is to control effectively the torque and flux. Torque control of an induction motor (IM) based on DTC strategy will be developed and a comprehensive study will be made in this project. Direct torque control is the first technology to control the real motor control variables of torque and flux. This method makes the rotor more accurate and fast control, high dynamic speed response and simple to control. The reference value can be calculated using the flux and torque estimation and also motor parameters.With the Joint progress of the power electronics and numerical electronics it is possible today to deal with the axis control with variable speed in low power applications. With these technological projections, various command approaches have been developed by the scientific community to master in real time, the flux and the torque of the electrical machines, the direct torque control (DTC) scheme being one of the most recent steps in this direction. This scheme provides excellent properties of regulation without rotational speed feedback. In this control scheme the electromagnetic torque and stator flux magnitude are estimated with only stator voltages and currents and this estimation does not depend on motor parameters except for the stator resistance.

In this paper a dual open loop speed control system based on two independent PWM signals of small permanent magnet DC (PMDC) motors using PIC16F877A microcontroller (MCU) has been designed and implemented. The Capture/Compare/PWM (CCP) modules of the MCU are configured as PWM mode and the MCU is programmed using flowcode software package to generate two PWM signals with various duty cycles at the same frequency. A dual H-bridge channel chip SN754410 is used to drive the motors. The variation of PWM duty cycles is related directly to controlling the DC motors terminal voltage which directly proportional with speed of each motor. The complete PWM control system model has been simulated using proteus design suite software package. The development of hardware and software of the dual DC motor speed control system has been explained and clarified.

The demand for electricity is increasing day-by-day and frequent power cuts is causing many problems in various areas such as household, domestic, farms, etc. Due to limited amount of power generation at power station and due to shortage of non-renewable sources, uninterruptible power supply being a biggest challenge in the entire world. In this paper, a smart emergency light is designed, developed and tested for use it in various applications such as home, industries, agricultural sector and shops, etc. The developed energy lamp has no running cost and has low initial cost. The main objective of this work is to provide the smart emergency light with solar power to the farmers. This work will help the farmers in many ways such as protecting the fields from yield animals. It can also be used as emergency light and entertainment, etc. The main applications of this work is that it can used as FM radio, USB charging, music by memory card, mini fan, torch light, etc. This can also be controlled by remote. The battery can be used for all these applications. This battery can be charged by two ways using solar energy and AC mains supply. The developed lamp is tested in the real time environment.

Our project presents a systematic procedure for modeling and simulation of a singlemachine infinite-bus power system installed with a thyristor controlled series compensator (TCSC).We used TCSC so that impact of TCSC on power system stability can be more reasonably evaluated. The model of the example power system is developed using MATLAB/SIMULINK and the system results are being presented to validate the effectiveness of using TCSC on power system stability.

DC/DC converters are massively used for switch-mode regulated power supply, renewable energy conversion systems and electrical drives. Conventionally analog methods were popular for control of these converters. This paper elucidates a digital controller using digital filter architecture, which supports fixed-point algorithm. Digital controller application to DC/DC converters has always been considered because of their superiority over analog controller. In digital controller, the control strategy can be altered or reprogrammed without the need of significant hardware changes. The digital controller improves response of DC-DC converter by varying loop-gain, cross-over frequency and phase margin. Closed loop digital control of buck and boost converter is presented and the results are obtained for varying operating conditions and verified using MATLAB/Simulink.

In comparison to conventional power plants characterized by Synchronous Generators (GS), Distributed Generation units (DG) usually do not have damping or rotational inertia properties. With the increase of DG sources in the electrical system, the impact of low inertia and damping effect on the stability and dynamic performance of the grid increases. A solution to improve the stability of a power system is to provide virtual inertia by Virtual Synchronous Generators (VSG).
Using simulation in the PSCAD/EMTDC® software, this paper proves the efficiency of the virtual synchronous generator as a strategy to improve the static and dynamic stability of the frequency in power systems, by comparisons with the conventional control strategy, the PQ control, in a modeled scenario with characteristic conditions of the Sistema Interligado Nacional (SIN).

Rapid depletion of fossil fuel reserves, and concerns over climate change have encouraged power generation from sustainable energy based microgrids. And to address the necessity of three-phase inverters in microgrid systems or sustainable-powered households, an Arduino-based three-phase inverter using MOSFET is designed, which converts DC into three-phase AC power. The designed system generates 223V square signals at each phase from a 12V battery through switching of three stages of power MOSFETs using pulse width modulation (PWM) signals at their gates from an Arduino Uno. Each stage of power MOSFETs consists of six transistors making it eighteen in total, which are used to perform the inversion process separately for each three single-phase connections. The system is programmed using an Arduino Uno to generate PWM signals and to keep 120 degrees phase displacement among each phase. Three step-up transformers are coupled at the outputs of MOSFET stages for amplification. The system...

Rapid depletion of fossil fuel reserves, and concerns over climate change have encouraged power generation from sustainable energy based microgrids. And to address the necessity of three-phase inverters in microgrid systems or sustainable-powered households, an Arduino-based three-phase inverter using MOSFET is designed, which converts DC into three-phase AC power. The designed system generates 223V square signals at each phase from a 12V battery through switching of three stages of power MOSFETs using pulse width modulation (PWM) signals at their gates from an Arduino Uno. Each stage of power MOSFETs consists of six transistors making it eighteen in total, which are used to perform the inversion process separately for each three single-phase connections. The system is programmed using an Arduino Uno to generate PWM signals and to keep 120 degrees phase displacement among each phase. Three step-up transformers are coupled at the outputs of MOSFET stages for amplification. The system...

In this study, a three-phase ac – dc converter using three single-phase pulse-width-modulated zero-voltage transition (ZVT), soft-switched boost converter in modular approach is presented. The novelty of the active snubber cell is that, it provides ZVT turn-on and zero-voltage switching (ZVS) turn-off for the main switch without extra current or voltage stress. Auxiliary switch is turned on near zero-current switching without additional voltage stress and turns off near ZVS. The input line current and output voltage are controlled by the proposed power factor correction (PFC) converter in very wide load range. This PFC converter has ease of control as well as a simple structure. In this study, detailed steady-state analysis of proposed converter is presented, and this theoretical analysis is verified exactly by 400 V, 1.5 kW and 100 kHz prototype. This prototype has total efficiency of 97.3% and 0.9996 power factor with input line sinusoidal current at full load.

In the cutting system by the method of plasma cutting, the distance of torch to cut material greatly affect the success of cutting material. This research aims to make the control of high torch motor drive, with controller input coming from the output voltage of plasma cutting machine of Hyperterm Powermax85 which has been reduced by 50 times the actual plasma output value of plasma machine during cutting process. The problem limitation of the manufacture of this tool is that it controls only one driving motor with one axis, up and down. In this study, the measurement of output voltage is done by using digital clamp meter and digital multimeter while to measure the distance of torch by using filler gauge and caliper. Then, the tool has been made, tested the functionality of the tool by adjusting the position of the workpiece by reviewing the kerf value changes. Based on the measurement of torch distance to material from 0mm to 8mm distance, the material condition is cut off and when the distance is 9mm, the material condition is not cut. Then by taking large data of plasma output voltage which has been divide 50 times by voltage divider on plasma machine cutting to torch distance to cutting material, each of 0mm, 2mm, 4mm, 6mm, and 8mm, obtained data of average voltage of 2,620 V, 2,755 V, 2,995 V, 3,185 V, and 3,243 V. So based on the data, there is a relationship between the change of voltage (plasma output) to the distance (torch to cut material) that is: V = 0.083 (Distance) + constant. While with cutting test of material set at different distance with fixed cutting machine position, this tool can cut the material without any part of the material that is not cut with the change of kerf value of 0.4mm from the initial value of 2.7 mm.

Abstract- In recent years the industrial application areas of the high performance AC drives based on Direct Torque Controller (DTC) technique have gradually increased due to its advantages over the field oriented control technique. Direct torque control (DTC) is one of the most excellent control strategies of torque control in PMSM. It is considered as an alternative to the field oriented control (FOC) or vector control technique. These two control strategies are different on the operation principle but their objectives are the same. They aim to control effectively the torque and flux. Torque control of an PMSM based on DTC strategy has been developed and a comprehensive study is presented in this research. The performance of this control method has been demonstrated by simulations performed using a versatile simulation package, Matlab/Simulink. Several numerical simulations have been carried out in a steady state and transient operation on a speed control mode. Implementation of an actual drive system based on the suggested DTC including software and hardware, to validate its performance practically is presented. The suggested control strategy guarantees very good dynamic and steady state characteristics. The practical and simulation results show that the used DTC gives good dynamic performance and good tracking response.

2020 IEEE 4th International Conference on Intelligent Energy and Power.
Section I. Modern Energy Systems & Power Electronics
Section II. Renewable Energy Systems & Distributed Generation
Section III. Intelligent & Adaptive Systems in Smart Grid
Section IV. Industrial Electronics & Electrical Drives
Section V. Special Power Electronics Systems & Applications

The multilevel inverters have important place in the modern high voltage applications because of their high quality output in all load conditions. Number of Power electronic switches and DC voltage sources are the important factors of the inverter which define output levels and quality. Cascaded multilevel inverters are mostly capable of handling more power in the output side thus these inverters are preferred for industrial applications. This paper presents a modified cascaded multilevel inverter with lessened number of power semiconductor switches compared with conventional cascaded multilevel inverter and also it presents various multicarrier pulse width modulation (MCPWM) techniques based on modified cascaded multilevel Inverter. These techniques will reduce the harmonic distortions present in the output voltage waveform. The proposed multilevel inverter produces thirteen-level using symmetrical sub-multilevel cells. This paper focus on to improve the ac output voltage with lower harmonic distortion and reduce the total harmonic distortion (THD). The proposed circuit have been simulated with help of MATLAB/SIMULINK.

—Stability analysis is one of the most important aspects to determine the performance of electric drive system during dynamic and steady state operating conditions. This is especially important since the motor operates in wide range of frequencies with the complex types of control strategies such as field oriented control and direct torque control. A new dynamic model is developed to study the instantaneous effect of varying voltage/current. In addition small signal equations are developed to evaluate the control performance by using conventional techniques such as Bode plot, Nyquist plot etc. In practice voltage-current relationships are used to perform such study. In this paper, the dynamic model based on voltage-flux-linkage relationship is utilized to evaluate the control performance of the three phase induction motor drive system. The presented model offers advantage of simplified analysis and provides more meaningful information. A study of voltage-current model and voltage-flux-linkage model has been carried out in this paper and important inferences are drawn from it. Analytical and simulation approach is used in the paper.

Majority of  engineering  colleges, universities and
the technical institutions are undertaking all initiatives to stay competitive. Efforts are exerted to continuously improve the curriculum in order to provide quality and relevant education for the students in response to global call for outcomes-based education. This paper presents the procedures, techniques, methods,  and advantages of using Altium Designer software in teaching electronic circuits. Altium Designer is a schematic capture, simulation, and PCB design software, dedicated to analyzing electronic circuits which is based on interconnected icons of electronic components. The approach makes it easier for the students to visualize the system they are attempting to design, model, and study. Likewise, it makes debugging and error correction simpler. Moreover, an example has been provided  also  to show how to use  the software for teaching and research in electronic circuits.

"Abstract- In this paper, pulse width modulation soft switched DC-DC converter without high voltage & current stress is
described. This converter does not require any extra switch to achieve soft switching, which considerably simplifies the control
circuit. In this proposed converter, the switch is turned on under zero-current and is turned-off at almost zero-voltage condition. In
this converter , it is desirable to control the output voltage by pulse width modulation because of its simplicity and constant
frequency. The circuit is simulated using PSPICE and the output voltage is obtained as 100V for 50V input.
Index Terms—Pulse width modulation (PWM), soft single switched (SSS), zero current switching (ZCS), zero voltage switching
(ZVS)."

Recently, an adjustable speed drive (ASD) is
widely used on many industries. A powerfactor is one oJ'
important aspect to be considered, since it can
drawback reactive powet' to supply side during its
operaling condition. This paper presettts a discrete PID
algorithm which applied by inner and outer loops
controller circuit. This makes a better control action on
power factor correction (PFC) circuit based on buck
topology-. Three phase IGBT inverter loaded by l0 hp
220/380 V 50 Hz squirrel cage induction ntotor is used
as a PFC load to meet real implementation on
industries. This proposed sl,srem is designed and
simulated by PSIM sofnuare. From the simulation result,
a control circuit achiet;e its best perJbrmance. A power
fa ctor increa s e s ignifi cantly.