Showing papers by "Sanjeevikumar Padmanaban published in 2018"
TL;DR: A comprehensive study of power quality in power systems, including the systems with dc and renewable sources is done, and power quality monitoring techniques and possible solutions of the power quality issues for the power systems are elaborately studied.
Abstract: This paper discusses the power quality issues for distributed generation systems based on renewable energy sources, such as solar and wind energy. A thorough discussion about the power quality issues is conducted here. This paper starts with the power quality issues, followed by discussions of basic standards. A comprehensive study of power quality in power systems, including the systems with dc and renewable sources is done in this paper. Power quality monitoring techniques and possible solutions of the power quality issues for the power systems are elaborately studied. Then, we analyze the methods of mitigation of these problems using custom power devices, such as D-STATCOM, UPQC, UPS, TVSS, DVR, etc., for micro grid systems. For renewable energy systems, STATCOM can be a potential choice due to its several advantages, whereas spinning reserve can enhance the power quality in traditional systems. At Last, we study the power quality in dc systems. Simpler arrangement and higher reliability are two main advantages of the dc systems though it faces other power quality issues, such as instability and poor detection of faults.
223 citations
TL;DR: A modified power ratio variable step (MPRVS) based perturb & observe (P&O) method has been proposed in the PV MPPT action which forces the operating point close to maximum power point (MPP).
Abstract: This research work deals with the modeling and control of a hybrid photovoltaic (PV)-Wind micro-grid using Quasi Z-source inverter (QZsi). This inverter has major benefits as it provides better buck/boost characteristics, can regulate the phase angle output, has less harmonic contents, does not require the filter and has high power performance characteristics over the conventional inverter. A single ended primary inductance converter (SEPIC) module used as DC-DC switched power apparatus is employed for maximum power point tracking (MPPT) functions which provide high voltage gain throughout the process. Moreover, a modified power ratio variable step (MPRVS) based perturb & observe (P&O) method has been proposed, as part of the PV MPPT action, which forces the operating point close to the maximum power point (MPP). The proposed controller effectively correlates with the hybrid PV, Wind and battery system and provides integration of distributed generation (DG) with loads under varying operating conditions. The proposed standalone micro grid system is applicable specifically in rural places. The dSPACE real-time hardware platform has been employed to test the proposed micro grid system under varying wind speed, solar irradiation, load cutting and removing conditions etc. The experimental results based on a real-time digital platform, under dynamic conditions, justify the performance of a hybrid PV-Wind micro-grid with Quasi Z-Source inverter topology.
104 citations
TL;DR: The fuzzy space vector pulse width modulation technique provides less current harmonic content, fixed switching pattern, protection from over current, low switching losses and able to handle the non-linearities and uncertainties of the photovoltaic-wind grid integrated system.
Abstract: This research study presents the fuzzy space vector pulse width modulation (FSVPWM) method of current control for three-phase voltage source inverter. The hybrid fuzzy particle swarm optimisation-based maximum power point (MPP) tracking algorithm has been employed to obtain high tracking efficiency as well as optimal MPP under adverse operating states. The FSVPWM technique provides less current harmonic content, fixed switching pattern, protection from over current, low switching losses and able to handle the non-linearities and uncertainties of the photovoltaic-wind grid integrated system. Grid synchronisation with sinusoidal current injection is achieved using the inverter controller. Fuzzy logic controller-based SVPWM controller compensates current error and provides DC-link utilisation with high efficiency. The experimental responses have been validated using MATLAB/Simulink interfaced real-time dSPACE DS 1104 controller. Irrespective of solar irradiance and wind velocity, the proposed hybrid system obeys MPP accurately with high performance.
100 citations
TL;DR: A comprehensive review is presented on accomplished research work on stabilization of dc and ac microgrid system stabilization techniques, which can basically be classified as compensation done at feeder side; by adding intermediate circuitry; and at load side.
Abstract: Microgrid, because of its advantages over conventional utility grids, is a prudent approach to implement renewable resource-based electricity generation. Despite its advantages, microgrid has to operate with a significant proportion of constant power loads that exhibit negative incremental impedance and thus cause serious instability in the system. In this paper, a comprehensive review is presented on accomplished research work on stabilization of dc and ac microgrid. After reviewing these, microgrid system stabilization techniques are classified with required discussions. As found out in this paper, the stabilization techniques can basically be classified as compensation done: 1) at feeder side; 2) by adding intermediate circuitry; and 3) at load side. Finally, after analyzing the merits and drawbacks of each generalized technique, several infographics are presented to highlight the key findings of this paper.
82 citations
TL;DR: In this article, a new transformer and switched capacitor-based Boost Converter (T & SC-BC) is proposed for highvoltage/low-current renewable energy applications.
Abstract: In this article a new Transformer and Switched Capacitor-based Boost Converter (T & SC-BC) is proposed for high-voltage/low-current renewable energy applications. The proposed T & SC-BC is an original extension for DC-DC boost converter which is designed by utilizing a transformer and switched capacitor (T & SC). Photovoltaic (PV) energy is a fast emergent segment among the renewable energy systems. The proposed T & SC-BC combines the features of the conventional boost converter and T & SC to achieve a high voltage conversion ratio. A Maximum Power Point Tracking (MPPT) controller is compulsory and necessary in a PV system to extract maximum power. Thus, a photovoltaic MPPT control mechanism also articulated for the proposed T & SC-BC. The voltage conversion ratio (Vo/Vin) of proposed converter is (1 + k)/(1 − D) where, k is the turns ratio of the transformer and D is the duty cycle (thus, the converter provides 9.26, 13.88, 50/3 voltage conversion ratios at 78.4 duty cycle with k = 1, 2, 2.6, respectively). The conspicuous features of proposed T & SC-BC are: (i) a high voltage conversion ratio (Vo/Vin); (ii) continuous input current (Iin); (iii) single switch topology; (iv) single input source; (v) low drain to source voltage (VDS) rating of control switch; (vi) a single inductor and a single untapped transformer are used. Moreover, the proposed T & SC-BC topology was compared with recently addressed DC-DC converters in terms of number of components, cost, voltage conversion ratio, ripples, efficiency and power range. Simulation and experimental results are provided which validate the functionality, design and concept of the proposed approach.
69 citations
TL;DR: A hybrid Artificial Neural Network (ANN)-Fuzzy Logic Control (FLC) tuned Flower Pollination Algorithm as a Maximum Power Point Tracker (MPPT) is employed to amend root mean square error of photovoltaic modeling.
Abstract: In this research paper, a hybrid Artificial Neural Network (ANN)-Fuzzy Logic Control (FLC) tuned Flower Pollination Algorithm (FPA) as a Maximum Power Point Tracker (MPPT) is employed to amend root mean square error (RMSE) of photovoltaic (PV) modeling. Moreover, Gaussian membership functions have been considered for fuzzy controller design. This paper interprets the Luo converter occupied brushless DC motor (BLDC)-directed PV water pump application. Experimental responses certify the effectiveness of the suggested motor-pump system supporting diverse operating states. The Luo converter, a newly developed DC-DC converter, has high power density, better voltage gain transfer and superior output waveform and can track optimal power from PV modules. For BLDC speed control there is no extra circuitry, and phase current sensors are enforced for this scheme. The most recent attempt using adaptive neuro-fuzzy inference system (ANFIS)-FPA-operated BLDC directed PV pump with advanced Luo converter, has not been formerly conferred.
65 citations
TL;DR: In this paper, some problems regarding energy scenarios, energy storage systems, grid infrastructure and communication systems in the supply and demand side of the grid are reviewed, and some solutions for these problems are presented.
Abstract: The increase in the emission of greenhouse gases (GHG) is one of the most important problems in the world. Decreasing GHG emissions will be a big challenge in the future. The transportation sector uses a significant part of petroleum production in the world, and this leads to an increase in the emission of GHG. The result of this issue is that the population of the world befouls the environment by the transportation system automatically. Electric Vehicles (EV) have the potential to solve a big part of GHG emission and energy efficiency issues such as the stability and reliability of energy. Therefore, the EV and grid relation is limited to the Vehicle-to-Grid (V2G) or Grid-to-Vehicle (G2V) function. Consequently, the grid has temporary energy storage in EVs’ batteries and electricity in exchange for fossil energy in vehicles. The energy actors and their research teams have determined some targets for 2050; hence, they hope to decrease the world temperature by 6 °C, or at least by 2 °C in the normal condition. Fulfilment of these scenarios requires suitable grid infrastructure, but in most countries, the grid does not have a suitable background to apply in those scenarios. In this paper, some problems regarding energy scenarios, energy storage systems, grid infrastructure and communication systems in the supply and demand side of the grid are reviewed.
47 citations
TL;DR: An artificial neural network (ANN) based maximum power point tracking (MPPT) control strategy for wind energy conversion system (WECS) implemented with a DC/DC converter using a radial basis function network (RBFN) based neural network control strategy.
Abstract: This paper proposes an artificial neural network (ANN) based maximum power point tracking (MPPT) control strategy for wind energy conversion system (WECS) implemented with a DC/DC converter. The proposed topology utilizes a radial basis function network (RBFN) based neural network control strategy to extract the maximum available power from the wind velocity. The results are compared with a classical Perturb and Observe (P&O) method and Back propagation network (BPN) method. In order to achieve a high voltage rating, the system is implemented with a quadratic boost converter and the performance of the converter is validated with a boost and single ended primary inductance converter (SEPIC). The performance of the MPPT technique along with a DC/DC converter is demonstrated using MATLAB/Simulink.
44 citations
TL;DR: The proposed energy management strategy (EMS) for a DC microgrid to supply power to rural communities with solar, wind, fuel cell, and batteries as input sources is offered and the performance of the system is analyzed based on different operating conditions of the input sources.
Abstract: The AC and DC power system structures need to be modernized to meet consumer demands. DC microgrids are suitably admired due to their high efficiency, consistency, reliability, and load sharing performance, when interconnected to DC renewable and storage sources. The main control objective for any DC microgrid is providing proper load–power balancing based on the Distributed Generator (DG) sources. Due to the intermittent nature of renewable energy sources, batteries play an important role in load–power balancing in a DC microgrid. The existing energy management strategy may be able to meet the load demand. However, that technique is not suitable forrural communities’ power system structure. This research offers an energy management strategy (EMS) for a DC microgrid to supply power to rural communities with solar, wind, fuel cell, and batteries as input sources. The proposed EMS performs the load–power balancing between each source (renewable and storage) in a DC microgrid for dynamic load variation. Here, the EMS handles two battery sources (one is used to deliver power to the priority load, and the other is utilized in the common DC bus) to meet the required demand. The proposed EMS is capable of handling load–power balancing using renewable energy sources with less consumption of non- conventional energy sources (such as a diesel generator). The performance of the system is analyzed based on different operating conditions of the input sources. The MATLAB/Simulink simulation model for the proposed DC microgrid with their EMS control system is developed and investigated, and their results are tabulated under different input and load conditions. The proposed EMS is verified through a laboratory real-time DC microgrid experimental setup, and the results are discussed.
42 citations
TL;DR: Analytical and simulation results prove the robustness and correctness of the technique proposed in this paper, and only exact solutions to the low-order harmonics elimination for Cascaded H-bridge inverter are reported for all modulation indices.
Abstract: Considering the aim of having low switching losses, especially in medium-voltage and high-power converters, the pre-programmed pulse width modulation technique is very useful because the generated harmonic content can be known in advance and optimized. Among the different low switching frequency techniques, the Selective Harmonics Elimination (SHE) modulation method is most suitable because of its direct control over the harmonic spectrum. This paper proposes a method for obtaining multiple solutions for selectively eliminating specific harmonics in a wide range of modulation indices by using modified Newton–Raphson (NR) and pattern generation techniques. The different pattern generation and synthesis approach provide more degrees of freedom and a way to operate the converter in a wide range of modulation. The modified Newton–Raphson technique is not complex and ensures fast convergence on a solution. Moreover, multiple solutions are obtained by keeping a very small increase in the modulation index. In the previous methods, solutions were not obtainable at all modulation indices. In this paper, only exact solutions to the low-order harmonics elimination for Cascaded H-bridge inverter are reported for all modulation indices. Analytical and simulation results prove the robustness and correctness of the technique proposed in this paper.
35 citations
TL;DR: This research work deals with a hybrid control system based integrated Cuk converter fed brushless DC motor for power factor correction and assesses adequacy of the proposed method, but the power factor broke down.
Abstract: This research work deals with a hybrid control system based integrated Cuk converter fed brushless DC motor (BLDCM) for power factor correction. In this work, moth-flame optimization (MFO) and a fuzzy logic controller (FLC) have been combined and a moth-flame fuzzy logic controller (MFOFLC) has been proposed. Firstly, the BLDC motor modeling is composed with the power factor correction (PFC) based integrated Cuk converter and BLDC speed is regulated using variable DC-Link inverter voltage which results in a low switching operation with fewer switched losses. Here, with the use of a switched inductor, the task and execution of the proposed converter is redesigned. The DBR (diode bridge rectifier) trailed by a proposed PFC based integrated Cuk converter operates in discontinuous inductor conduction mode (DICM) for achievement of better power factor. MFO is exhibited for gathering of a dataset from the input voltage signal. At that point, separated datasets are sent to the FLC to improve the updating function and minimization of torque ripple. However, our main objective is to assess adequacy of the proposed method, but the power factor broke down. The execution of the proposed control methodology is executed in the MATLAB/Simulink working platform and the display is assessed with the existing techniques.
TL;DR: This paper mainly focuses on the analysis, DC-transformer modeling, comparison, and experimental investigation of a non-inverting and non-isolated Nx multilevel boost converter (Nx MBC) for low to high DC applications.
Abstract: This paper mainly focuses on the analysis, DC-transformer modeling, comparison, and experimental investigation of a non-inverting and non-isolated Nx multilevel boost converter (Nx MBC) for low to high DC applications. Recently, numerous isolated and non-isolated DC-DC converter configurations have been addressed for low to high DC voltage conversion purposes, which is vital for several applications (e.g., renewable energy, medical equipment, hybrid vehicles, fuel cells, DC-links, multilevel inverters, and drive applications), by utilizing and modifying the structure of reactive elements (switched capacitors and switched inductor circuitry). Among all the switched reactive structures, voltage multiplier circuitry provides a feasible solution for low to high DC voltage conversion due to its flexible and modular structure, voltage clamping capability, reduced rating of components, and ease of modification. Non-inverting and non-isolated Nx MBC combine the features and structures of conventional boost converters and voltage multiplier circuitry. DC-transformer modeling of Nx MBC is discussed for the continuous current mode (CCM) and discontinuous current mode (DCM), which helps to analyze the characteristics of the converter in a more practical way and helps to study the effect of semiconductor components, internal resistances, and load on the voltage conversion ratio of the converter. The mode of operation of Nx MBC in the CCM and DCM is also discussed with the boundary condition. The derived analysis is verified by simulations and experimental investigations, and the obtained results of 3x MBC always show good agreement with each other and the theoretical analysis.
TL;DR: Two multilevel pulse width modulation (PWM) methods; multi-carrier sine PWM (MCSPWM) and space vector P WM (SVPWM) has been considered for NPC-MLI and results convey that the SVPWM method is superior when compared with the MCSPWM algorithms.
Abstract: The Multilevel inverter topologies (MLIs) are increasingly being used, which is the preferred choice in many industrial Medium-voltage (MV) applications. The inherent low switching frequency in med...
12 Jun 2018
TL;DR: Support Vector Machine is one of the classification methods in machine learning algorithm where it can be easily classified the cavitation problem and the method of SVM can more efficiently detect the Cavitation problem with the centrifugal water pump.
Abstract: Cavitation is one of the major disadvantages in pumping system, which enhance to form bubbles in the pipeline and it reduces the efficiency of the pump. So it should be identified and take the preventive measure. Machine Learning is a fast and computational method which can easily detect any faults in the pumping system. Still now lots of work has been done on a detection of fault in the pumping system, but mainly those work has done based on vibration details and variation of speed. The paper presents how by the help of machine learning algorithm by varying the speed and pressure cavitation can be identified. It is the comparative study between how the vibration and speed together affects the cavitation result and variation of speed and pressure affects the cavitation. Support Vector Machine is one of the classification methods in machine learning algorithm where it can be easily classified the cavitation problem. So this paper analyses how the method of SVM can more efficiently detect the cavitation problem with the centrifugal water pump.
TL;DR: Simulation results confirm that, in transient periods, sliding mode controller remarkably outperforms its counterpart PI controller.
Abstract: This paper presents sliding mode control of sensor-less parallel-connected two five-phase permanent magnet synchronous machines (PMSMs) fed by a single five-leg inverter. For both machines, the rotor speeds and rotor positions as well as load torques are estimated by using Extended Kalman Filter (EKF) scheme. Fully decoupled control of both machines is possible via an appropriate phase transposition while connecting the stator windings parallel and employing proposed speed sensor-less method. In the resulting parallel-connected two-machine drive, the independent control of each machine in the group is achieved by controlling the stator currents and speed of each machine under vector control consideration. The effectiveness of the proposed Extended Kalman Filter in conjunction with the sliding mode control is confirmed through application of different load torques for wide speed range operation. Comparison between sliding mode control and PI control of the proposed two-motor drive is provided. The speed response shows a short rise time, an overshoot during reverse operation and settling times is 0.075 s when PI control is used. The speed response obtained by SMC is without overshoot and follows its reference and settling time is 0.028 s. Simulation results confirm that, in transient periods, sliding mode controller remarkably outperforms its counterpart PI controller.
TL;DR: A new single phase nine-level inverter using two capacitors and a single DC source is introduced using two control algorithms namely charging algorithm and discharging algorithm to eliminate Voltage imbalances in the capacitors.
Abstract: This study introduces a new single phase nine-level inverter using two capacitors and a single DC source. Voltage imbalances in the capacitors are eliminated using two control algorithms namely charging algorithm and discharging algorithm. The charging algorithm is used to change the inverter switching states when the measured voltage across the capacitors is less than the prescribed value. Alternatively, if the voltage across the capacitors is greater than the set value, the discharging algorithm determines the switching pattern of the inverter switches. The proposed voltage balancing algorithm is very simple to implement and makes the proposed inverter attractive for industrial applications. An extensive comparison of the proposed inverter is made against other topologies proposed in the literature in terms of the components used. The proposed inverter is tested in both standalone and grid connected modes. The proposed inverter is simulated and implemented as a prototype in the laboratory. Experimental results obtained from the prototype confirm the high-quality transient performance of the proposed inverter in terms of its dc capacitor voltage balancing capability.
TL;DR: An enhanced Particle Swarm Optimization (PSO) based MPPT method for the photovoltaic system integrated through Z-Source inverter, which has the capability to track the maximum power point (MPP) during an extreme environmental condition.
Abstract: Maximum Power Point Tracking (MPPT) technique is used to extract maximum power from the photovoltaic system. This paper involves working on an enhanced Particle Swarm Optimization (PSO) based MPPT method for the photovoltaic (PV) system integrated through Z-Source inverter. The main benefit of the proposed method is the diminishing of the steady-state oscillation when the maximum power point (MPP) is located. Additionally, during an extreme environmental condition, such as partial shading and large fluctuations of irradiance and temperature, the proposed method has the capability to track the MPP. This algorithm is implemented in dspace 1104 controller. MATLAB simulations are carried out under varying irradiance and temperature conditions to evaluate its effectiveness. Its performance is compared with a conventional method like Perturb and observe (P&O) method.
27 Jun 2018
TL;DR: Simulation results of 100W proposed improved M-SIBC with considering three stages are provided and the results always show a good agreement with theoretical analysis and also validates the improvedM-SI network concept.
Abstract: In this article, an improved Multistage Switched Inductor (M-SI) based power converter or Improved Multistage Switched Inductor Boost Converter (Improved M-SIBC) is proposed for renewable applications which provides a key to enhancing the voltage conversion ratio. In the last decades, Switched Inductor (SI) and M-SI are the popular network/technique employed in DC-DC converter to achieve a high voltage conversion ratio. An improved SI and M-SI network/technique is proposed to enhance the existing the voltage conversion capabilities of SI and M-SI by replacing central uncontrolled switches by polarized capacitor. The anticipated power converter configuration combines the feature of the conventional boost converter and improved M-SI. The voltage conversion a capability is depends on the number of stages of M-SI and ON time of the control switch. The operation modes and characteristics of the proposed converter with steady state mathematical analysis for N-stages are discussed in detail. Moreover, the proposed converter compared with the existing converter in terms of the voltage conversion ratio and the detail of the number of components is also provided. Matrix Laboratory R2016a simulation results of 100W proposed improved M-SIBC with considering three stages are provided and the results always show a good agreement with theoretical analysis and also validates the improved M-SI network concept.
01 Sep 2018
TL;DR: In this paper, a five-level transistor clamped H-bridge (TCHB) inverter was further investigated, where semiconductor switches operating at carrier frequency were configured by Silicon Carbide (SiC) devices to reduce the dominant switching losses.
Abstract: Using wide bandgap (WBG) devices has been a promising solution to improve the efficiency of power inverters for photovoltaic (PV) applications. However, for multilevel inverters, using WBG devices to improve the inverter efficiency can increase the system cost dramatically due to the high price of WBG devices in the present market as well as the large number of power devices typically required in multilevel inverter topologies. In this paper, a five-level transistor clamped H-bridge (TCHB) inverter will be further investigated. This inverter requires much lower number of semiconductor switches and fewer isolated dc sources than the conventional cascaded H-bridge inverter. To improve the inverter efficiency, semiconductor switches operating at carrier frequency will be configured by Silicon Carbide (SiC) devices to reduce the dominant switching losses, while the switches operating at fundamental output frequency (i.e., grid frequency) will be constituted by Silicon (Si) devices. As a result, both of the peak efficiency and California Energy Commission (CEC) efficiency of the TCHB inverter are significantly improved and dramatic system cost increase is avoided. In addition, due to the faster saturation characteristic of the IGBT devices, the large short-circuit current in SiC MOSFETs is constrained under the condition of load short-circuit faults. In other words, this proposed “SiC+Si” hybrid TCHB inverter can ride through a load short-circuit fault. Simulation and experimental results are presented to confirm the benefits of this proposed hybrid TCHB inverter.
TL;DR: Histology studies revealed that silver nanoparticles to cause fibrosis, lipofuscin-like deposits and also gut disruption in earthworms, which was evidenced by histology.
Abstract: To evaluate the toxicity of the silver nanoparticle against earthworms - Eudrilus eugeniae, a model for soil organism. Silver nanoparticles were synthesised by chemical reduction and further characterised by UV Visible Spectroscopy and FeSEM. Earthworms were allowed to interact with different concentrations of the synthesized silver nanoparticles. After exposure period, histology and inductively coupled plasma optical emission spectrometry (ICP-OES) were done to determine the accumulation and toxic effects exhibited by the nanoparticle on earthworms. The synthesized nanoparticle was found to be between the size of 180 and 200 nm. Histology studies revealed that silver nanoparticles to cause fibrosis, lipofuscin-like deposits and also gut disruption in earthworms. Silver nanoparticles were found to be toxic to Eudrilus eugeniae, which was evidenced by histology.
04 Jun 2018
TL;DR: The advantage of proposed topology is reduced voltage stress across switching device, which results into better efficiency and voltage gain is increased without disturbing the main circuit.
Abstract: In this paper a non isolated, non inverting, single switch, high gain modified SEPIC with voltage multiplier dc-to-dc converter is proposed. The proposed circuit is a combination of modified version of conventional SEPIC converter and voltage multiplier unit. The voltage gain of proposed converter is increases to n time of (1/ (1-D) by extending the voltage multiplier unit by n time. The advantage of proposed topology is reduced voltage stress across switching device, which results into better efficiency and voltage gain is increased without disturbing the main circuit. In this paper, the detail operation of proposed converter with mathematical analysis is done. The proposed converter is simulated in MatLab R2016a for three level with 120W power. The mathematical analysis and simulation results validates the functionality of proposed converter.
TL;DR: The proposed methodology outperforms existing state-of-the-art approaches in wirelength reduction by about 18.65% and in congestion reduction by around 63%, while delivering the 30.35% power consumption.
Abstract: Multiple supply voltage is the most prevalent method for low power reduction in the design of modern Integrated circuits. Floorplanning process in this design performs positioning of functional blocks in the layout satisfying both fixed outline and voltage island constraints. The floorplans while satisfying these two significant constraints causes significant rise in wirelength and congestion. In this paper, a congestion and wirelength aware floorplanning algorithm is proposed which allows effective placement of functional blocks in the layout to satisfying fixed outline and voltage island constraints simultaneously. To perform voltage island floorplanning, the proposed algorithm uses Skewed binary tree representation scheme to operate the functional blocks in its predefined voltage level. The proposed methodology determines the feasible dimensions of the functional blocks in the representation which aids the placement process for the reduction of congestion and wirelength. With these optimal dimensions of the functional blocks, floorplanning is also performed for the layouts of aspect 1:1, 2:1, and 3:1, to evaluate the ability of proposed algorithm for satisfying the fixed outline constraint. The proposed methodology is implemented in the layout of InternationalWorkshop on Logic and Synthesis (IWLS) benchmarks circuits for experimental purpose. The resulting floorplans were iteratively optimized for optimal reduction of wirelength and congestion. Experimental results show that the proposed methodology outperforms existing state-of-the-art approaches in wirelength reduction by about 18.65% and in congestion reduction by around 63%, while delivering the 30.35% power consumption.
01 Aug 2018
TL;DR: A predictive controller that simultaneously controls the position, speed and the current of PMSM is presented and the performance of the proposed position controller is significantly improved by using the proposed feedforward terms in the cost function when comparing to thecost function without these terms.
Abstract: This paper presents a predictive controller that simultaneously controls the position, speed and the current of PMSM. The controller is based on finite control set model predictive control approach. Motion profile generator is used for the generation of reference signals. Signals generated there enter into the controller and act as feedforward signals that are evaluated inside of a cost function with other predictions. Measured position is used as a feedback and the speed and load torque are estimated by Kalman filter. The control is formulated in the dq coordinate frame. Simulation results show that the performance of the proposed position controller is significantly improved by using the proposed feedforward terms in the cost function when comparing to the cost function without these terms. The controller with improved cost function was also experimentally verified with Texas Instruments DSP.
TL;DR: The results are compared with three-phase self-excited induction generator (SEIG) to show the effectiveness of FPIG for high-power wind generation.
Abstract: Wind turbines with higher power ratings are desired to reduce construction cost and maintenance time and increase energy yields. Three-phase induction generators are widely used in renewable power ...
TL;DR: A novel scheme for the detection of island boundaries and stabilizing the system during autonomous operation and a wide area load shedding program is adopted based on DVSF to shed the load in weak bus-bars and stabilize the system.
Abstract: Distribution systems can form islands when faults occur. Each island represents a subsection with variable boundaries subject to the location of fault(s) in the system. A subsection with variable boundaries is referred to as an island in this paper. For operation in autonomous mode, it is imperative to detect the island configurations and stabilize these subsections. This paper presents a novel scheme for the detection of island boundaries and stabilizing the system during autonomous operation. In the first stage, a boundary detection method is proposed to detect the configuration of the island. In the second stage, a dynamic voltage sensitivity factor (DVSF) is proposed to assess the dynamic performance of the system. In the third stage, a wide area load shedding program is adopted based on DVSF to shed the load in weak bus-bars and stabilize the system. The proposed scheme is validated and tested on a generic 18-bus system using a combination of EMTDC/PSCAD and MATLAB software’s.
TL;DR: An optimal design of multiple Rx WPT system is proposed, which can eliminate cross coupling, frequency splitting issues and increase the power transfer efficiency (PTE) of selected Rx.
Abstract: Simultaneous power transfer to multiple receiver (Rx) system is one of the key advantages of wireless power transfer (WPT) system using magnetic resonance. However, determining the optimal condition to uniformly transfer the power to a selected Rx at high efficiency is the challenging task under the dynamic environment. The cross-coupling and frequency splitting are the dominant issues present in the multiple Rx dynamic WPT system. The existing analysis is performed by considering any one issue present in the system; on the other hand, the cross coupling and frequency splitting issues are interrelated in dynamic Rx’s, which requires a comprehensive design strategy by considering both the problems. This paper proposes an optimal design of multiple Rx WPT system, which can eliminate cross coupling, frequency splitting issues and increase the power transfer efficiency (PTE) of selected Rx. The cross-coupling rejection, uniform power transfer is performed by adding an additional relay coil and independent resonance frequency tuning with capacitive compensation to each Rx unit. The frequency splitting phenomena are eliminated using non-identical transmitter (Tx) and Rx coil structure which can maintain the coupling between the coil under the critical coupling limit. The mathematical analysis of the compensation capacitance calculation and optimal Tx coil size identification is performed for the four Rx WPT system. Finite element analysis and experimental investigation are carried out for the proposed design in static and dynamic conditions.
TL;DR: Results proved the advantages of the dual battery with the proposed BMS and fortify that the introduction of time-based tariffs and other incentives will further make investments in VRB highly attractive for renewable applications.
Abstract: This paper proposes an intelligent battery management system (BMS) implementing two large Vanadium Redox Battery (VRB) flow batteries in a master-slave mode to provide grid-level energy storage for a wind-solar hybrid power system. The proposed BMS is formulated to effectively meet a predetermined power dispatch formulated based on forecasted wind and solar data while incorporating features like peak shaving and ramp rate limiting. It is compared to a single battery module operated system to showcase the advantages of the proposed intelligent dual battery module in terms of appreciable reduction in battery size and costs while exhibiting improved lifecycle performance. The battery size is optimized based on heuristic optimization algorithms and modelled in Matlab/Simulink environment. An intelligent fuzzy-based BMS is used to control the dual VRB model to ensure optimized power sharing between batteries. The simulations were carried out and an in-depth economic analysis conducted to analyze the costs and other financial metrics of the hybrid project. Results proved the advantages of the dual battery with the proposed BMS and fortify that the introduction of time-based tariffs and other incentives will further make investments in VRB highly attractive for renewable applications.
13 Jun 2018
TL;DR: In this article, a new voltage doubler based DC-DC converter topology was proposed for the high-voltage/low-current renewable energy applications, which is well suited for high output voltage power converter such as a photovoltaic multilevel DC-AC converter system, renewable High Voltage Direct Current (HVDC) applications, Hybrid Electric Vehicles (HEV) etc.
Abstract: In this treatise, a new voltage doubler based DC-DC $2\mathrm {L}\mathrm {C}_{\mathrm {m}}-\mathrm {Y}$ power converter topologies are uttered for the high-voltage/low-current renewable energy applications. L-Y, 2L-Y, 2LC-Y and $2\mathrm {L}\mathrm {C}_{\mathrm {m}}-\mathrm {Y}$ power converter categories are recently proposed in the existing X-Y converter family. To provide an effective and viable solution to renewable energy system; four new voltage doubler based converters $(2\mathrm {L}\mathrm {C}_{\mathrm {m}}$-LVD, $2\mathrm {L}\mathrm {C}_{\mathrm {m}}-2\mathrm {L}\mathrm {V}\mathrm {D}, 2\mathrm {L}\mathrm {C}_{\mathrm {m}}-2$LCVD and $2\mathrm {L}\mathrm {C}_{\mathrm {m}}-2\mathrm {L}\mathrm {C}_{\mathrm {m}}\mathrm {V}\mathrm {D}$ converters) are proposed in $2\mathrm {L}\mathrm {C}_{\mathrm {m}}-\mathrm {Y}$ converter category. The proposed converters are well suited for renewable energy applications which required high output voltage power converter such as a Photovoltaic Multilevel DC-AC converter system, renewable High Voltage Direct Current (HVDC) applications, Hybrid Electric Vehicles (HEV) etc. The perceptible characteristics of proposed $2\mathrm {L}\mathrm {C}_{\mathrm {m}}-\mathrm {Y}$ power converter topologies are presented in detail. Working of $2\mathrm {L}\mathrm {C}_{\mathrm {m}}-\mathrm {Y}$ proposed converters with the derivation of $Vo/V_{in}$ is discussed in detail. Proposed converter topologies are simulated in the Numerical Computing Matrix Laboratory $9.0~(\mathrm {R}2016\mathrm {a})$ software. The simulation results are discussed in details and it constantly showed the high-quality agreement with hypothetical analysis and validates the functionality and characteristics of the proposed $2\mathrm {L}\mathrm {C}_{\mathrm {m}}-\mathrm {Y}$ converter topologies of X-Y converter family.
01 Nov 2018
TL;DR: This study accomplishes a SMC to the modified SEPIC converter and also maintains the constant switching frequency, and simulations show impressive results with the expectations for different perturbation scenarios and matches the developed theoretical background.
Abstract: This paper investigates, analyses and presents a control scheme for a modified SEPIC converter. High voltage conversion ratio is accomplished by using fewer passive components. The modified SEPIC converter is a combination of two different circuits. The first part is a standard SEPIC converter circuit, and the second part is a switched capacitor circuit. A high voltage conversion ratio is achieved up to 29 times by the input voltage, if the duty ratio is kept 0.9. However, high performance control of DC-DC converters is a difficult task due to nonlinearities and higher order behaviour. Control methods, such as PI controller or linear state space approaches cannot achieve the goal in a wide operating range. Instead, Sliding Mode Control (SMC) method is a suitable solution in such circumtances. Since it is insensitive to parameter deviations and free from system dynamics. This study accomplishes a SMC to the modified SEPIC converter and also maintains the constant switching frequency. The complete DC-DC converter along with the control algorithm using Matlab/Simulink simulation software is demonstrated. Simulations show impressive results with the expectations for different perturbation scenarios and matches the developed theoretical background.
01 Sep 2018
TL;DR: Experimental and simulation results are provided which validates the concept and always shows a good agreement with theoretical approaches.
Abstract: In this research treatise, a novel Calculus Based Unipolar Double Reference Single Carrier PWM (CB-UDR-SC PWM) is proposed for single phase T-Multilevel Inverter (T-MLI) for renewable energy applications. The main downsides of conventional two-level inverters are i) $\boldsymbol{d}\boldsymbol{v}/\boldsymbol{d}\boldsymbol{t}$ of output voltage is high, ii) requirement of fast switching devices, iii) requirement of bulky filter, iv) Electromagnetic Interference is high, iv) temperature of switches is increases with high speed, v) not suitable for high power application and vi) high THD. Single switch with four diodes are used to design the auxiliary structure of T-MLI structure. Total 8 diodes (including anti-parallel diode of switch), five switches are used to design T-MLI for five-level. CB-UDR-SC PWM methodology is proposed by utilizing two modulation signals (derived from calculus) and single carrier. The technique is employed to investigate T-MLI circuitry is for the under-modulation index. The general idea of calculus based PWM is explained in detailed. SPARTAN 3E-XCS250E FPGA trainer kit is utilized to obtain PWM for the switches of T-MLI. Experimental and simulation results are provided which validates the concept and always shows a good agreement with theoretical approaches.