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This paper presents Space Vector Modulation (SVM) sequences that reduce Common Mode Voltage (CMV) in Dual Three-phase Asymmetrical Induction Motor (DTAIM). At first, two existing SVM techniques such as Reference SVM (RSVM) and CMV1 are studied. Additionally, three new switching sequences are developed as CMV2, CMV3 and DCMV3, which reduce peak magnitude of CMV by 66.8% in comparison with RSVM technique. In SVM techniques, to obtain least CMV, zero vectors are usually replaced by two opposite large Active voltage Vectors (AV) with equal time duration. In such topologies like CMV1, total six AVs are utilized to synthesize the reference vector. The proposed SVM technique CMV2 utilizes only five large AVs to synthesize the reference vector and reduces CMV. Selection of five neighbouring AVs is reflected in reduction of harmonic flux trajectories and stator current ripple in proposed techniques. Additionally, two more switching sequences (CMV3 and DCMV3) are developed related to utilization of specific zero voltage vectors in all sectors (7 and 56) that produce zero CMV. These two switching sequences also provide easy implementation feature during the development of c-code program. In this study, CMV and stator current ripple are considered as performance parameters for different SVM techniques. All SVM techniques are analysed by analytical results, computer simulations, and using prototype test setup of DTAIM fed by Dual Three-phase Voltage Source Inverters (DTVSIs). [ABSTRACT FROM AUTHOR]

There is a consistent demand for reliable, efficient, small-sized, and light weight on-board chargers for vehicular battery charging applications. In view of aforesaid requirements, these chargers are restricted to Level-1 and Level-2 charging. Therefore, it leads to larger charging time. The proposed charger is integrated with propulsion machine drive system that serves to utilize the high power-rated electrical machine and motor-drive voltage source converter to facilitate vehicular battery charging when the vehicle is not running. This article presents mathematical modeling under various operational modes, analysis, and design considerations for the proposed system configuration. The entire system is developed in sim-power system toolbox of MATLAB software and tested in real-time implementation. The performance investigations of proposed charging system are carried out for vehicle battery charging under steady state as well as source variations. Furthermore, to ensure power quality features, total harmonic distortions of source voltage, and current and input power factor, are monitored. The salient features of proposed systems include no additional circuit, on-board charger suitable for fast charging, plugged in with single-phase, 230-V, 50-Hz outlet. It also offers a reduction in switch stress, reduced filter size, less ripple in current and voltage, and also improves the dynamic response. [ABSTRACT FROM AUTHOR]

This paper addresses the compensation of power quality problems such as balancing of load, compensation of neutral current, and distortions of the load current in a wind-based renewable energy system working at an isolated location for small consumers. For this purpose, an adaptive theory based momentum least mean square (MLMS) algorithm is used to operate the voltage source converter, which enhances the power quality in the system. This control is also responsible for keeping constant frequency and voltage at the point of common interface under mechanical and electrical transients. In addition, the reactive power is also compensated. The MLMS is a modified control of basic LMS that utilizes the past gradient information to reach improved adaptation performance instead of using its current value. This control has removed the drawback of LMS algorithms such as weight convergence dependence on the selection of the step size parameter. Moreover, it is observed that with inputs having high noise components, the MLMS algorithm performs better. Therefore, the application of the proposed control seems better in wind-based power generation where the input conditions are uncertain. The entire setup is developed in MATLAB/SIMULINK as well as tested in a real-time implementation. The performance results are observed to be effective. [ABSTRACT FROM AUTHOR]

The six-phase asymmetrical induction motors (SPIMs) are employed for high power medium voltage drive due to its attractive features of reduced stator copper loss, lower torque pulsation, higher torque per ampere, and higher reliability. In this paper, analysis of carrier-comparison-based pulse width modulation (PWM) techniques namely sinusoidal PWM and double zero-sequence injection PWM are carried out from a space vector perspective. Furthermore, new space vector pulsewidth modulation (SVPWM) techniques are developed by modifying the switching sequences of carrier-based PWM techniques. A comprehensive analysis of these PWM techniques is carried out in terms of harmonic flux trajectories, squared harmonic flux, and harmonic distortion factor (HDF). As a result, modified SVPWM technique namely 6ΦSVM3 is found superior to aforesaid PWM techniques, which significantly reduces HDF and provides lower current total harmonic distortion (THD). The experimental results of aforementioned PWM techniques are obtained and verified from six phase asymmetrical induction motor fed by dual two-level 3ΦVSIs. This paper is also accompanied by a video file of experimental test setup recorded while 6ΦSVM2 is running on SPIM. [ABSTRACT FROM AUTHOR]

This paper describes a control algorithm based on modified enhanced phase-locked loop (MEPLL) in dynamic voltage restorer (DVR). It compensates distortions and unbalances in the supply voltage along with voltage sag/swell. Three-phase MEPLL extracts the fundamental positive-, negative-, and zero-sequence components from the distorted/unbalanced signals. Further fundamental positive-sequence components are used in the reference load voltage calculations. In addition to track the angle of the input signals similar to the conventional PLLs, the proposed algorithm (MEPLL) offers features of getting fundamental and sequential components in case of distorted or unbalanced grid voltage for all the three phases simultaneously. Optimization approach named as autonomous groups particle swarm optimization, a variant of PSO is used for the calculation of PI-controller gains. The integrated time square error is used as a cost function for optimization of an error between the reference and actual values. This approach of tuning PI gains improves the performance by eliminating the manual process. The proposed control algorithm is implemented in DVR system using MATLAB software and validated in a laboratory environment. The performance shows that the proposed control algorithm gives time effective and satisfactory solution for the unpredictable issues mentioned. [ABSTRACT FROM AUTHOR]

Most of the two-stage converters for electric bike battery charging comprise of a boost converter for power factor correction (PFC) followed by a dc–dc converter with universal input voltage. These two-stage conversions suffer from poor efficiency and increased component count. In this paper, a single-stage switched inductor Cuk converter based PFC converter is proposed, which offers high step-down gain, low current stress, high efficiency, and reduced component count. The operational analysis and design equations for various components of the proposed converter are carried out in continuous current mode. This paper presents mathematical modeling, analysis, simulation, and experimentation on the proposed converter rated for 500 W, 48 V/10.4 A. The performance investigation of the proposed converter with respect to power quality indices like voltage total harmonic distortion (THD), current THD, and total power factor is carried out with various types of loads such as resistive load and battery load in both constant voltage (CV) and constant current (CC) mode. Furthermore, the dynamic performance of the proposed converter with battery charging is investigated in CV mode and CC mode with respect to the wide range of supply variations. [ABSTRACT FROM AUTHOR]

This paper presents the new controller for voltage and frequency control (VFC) of two-winding single-phase induction generator. It provides coordinated control of battery energy storage system (BESS) and dump load during the mismatch of power between loads and generator using VFC loop. It provides protection against overcharging of BESS. For this purpose adaptive vectorial filter (AVF) is implemented to operate single-phase induction generator in standalone mode of operation for power quality features. The unique feature of this filtering technique is its simplicity and no other analogy filters are required to produce the reconstructed signal of fundamental frequency. This procedure uses the vectorial natures of the single-phase input signal, which is decomposed by shifting property in the α–β orientation frame in order to get the diverse harmonic constituents. The design and analysis of AVFs for the proposed system is carried out in order to find the required performance. The proposed control method is evaluated by simulations in MATLAB/Simulink followed by experimental validation in laboratory for signifying its capability to execute different harmonic constituents under an extremely distorted generator current. Apart from control method, design of generator with finite-element method and its electromagnetic properties are also discussed. [ABSTRACT FROM AUTHOR]

In this paper, Lorentzian norm based adaptive filter (LAF) is implemented to control voltage source converter (VSC) for improvement in power quality of three phase four wire wind based distributed generation system. This control algorithm operates VSC to control the terminal voltage and frequency in allowable range. In addition to above, neutral current compensation, load balancing, reactive power, and harmonic compensation are also carried out. Therefore, in the system, the generator always supplies the active fundamental component of load current. The LAF is derived from a sliding window type objective function with Lorentzian norm of past errors to overcome bad effect of impulsive environment on system. Hence, it is most suitable filter in wind-based distributed generation system application in order to neutralize the effect of wind impulses on the voltage and frequency of the generator. The entire system comprises induction generator, VSC, and star-delta transformer and nonlinear load is developed in MATLAB Simulink followed by a prototype in the laboratory. The control performance of the said filter is evaluated and validated by simulation and experimental analysis. After performance observation, results are found satisfactory. [ABSTRACT FROM AUTHOR]