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Showing 1 to 20 of 58 for “"VSI"”.
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Modeling and Control Design of Vsi-Fed Pmsm Drive Systems With Active Load
… control design and detailed analysis of a VSI-fed PMSM drive system with active load is done through simulations of the system model, using modern simulation software packages. A new control method for the speed tracking control based on the estimation of the load torque profile is …
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The effects of Visual Stability Index (VSI) on fresh and hardened properties of Self Consolidating Concrete (SCC) under accelerated curing condition
… to analyze effects of visual stability index (VSI) on both fresh and hardened properties of Class P-SCC concrete under the accelerated curing using SURE CURE system. In addition, the relationship between VSI and fresh segregation of SCC is investigated. Finally, the results of this study are …
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The effects of Visual Stability Index (VSI) on fresh segregation of self consolidating concrete (SCC) using fly ash class C and F
… the relationship between Visual stability index (VSI) and fresh segregation of SCC. Finally, recommend the specifications of fresh performance requirements for the Class A-SCC that the Tennessee Department of Transportation (TDOT) should apply to establish SCC stability and flowability during the …
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Control charts applying a sequential test at fixed sampling intervals with optional sampling at fixed times
In recent years, variable sampling interval (VSI) control charts have been intensively investigated. In contrast to traditional fixed sampling interval (FSI) control charts, VSI charts vary the sampling interval as a function of the data. VSI charts detect many process changes faster than their FSI …
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Visio-spatial intelligence (vsi) between premier league, first division rugby players and non-athletes in the development of a sportspecific visio-spatial intelligence test battery
… affect vision and visiospatial intelligence (VSI). However, a combination of factors could warrant a more holistic approach. This study summarised and compiled an overview of the factors affecting vision and VSI in athletes, covering those factors previously connected with sport, as well as …
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The mechanics of valve cooling in internal-combustion engines. Investigation into the effect of VSI on the heat flow from valves towards the cooling jacket.
Controlling the temperature of the exhaust valves is paramount for proper functioning of engines and for the long lifespan of valve train components. The majority of the heat outflow from the valve takes place along the valve-seat-cylinder head-coolant thermal path which is significantly influenced …
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Control of a Single-Phase Grid-Connected Voltage Source Inverter with LCL Filter
… grid-connected voltage source inverter (VSI) with an LCL filter that is used in renewable energy power conditioning applications. There are two main controllers that need to be designed: an external DC-bus voltage controller to balance the power flow coming into the VSI, and an internal …
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X control charts in the presence of correlation
… methods called variable sampling interval (VSI) schemes have been developed where one takes the next observation sooner than usual if there is an indication that the process is operating off the target value. Another traditional assumption behind most statistical process control charts is …
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Medium voltage petrochemical drives : soft start and adjustable speed systems
… on the application of Voltage Source Inverters (VSIs) for these petrochemical loads. An application concept is described where the converter is used to start several motors and to drive one at adjustable speed. Associated benefits in terms of availability, hazardous areas and switching surge …
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High Power Density and Overcurrent Protection Challenges in the Design of a Three-Phase Voltage Source Inverter for Motor Drive Applications
The voltage source inverter (VSI) is certainly the most popular topology used in dc to ac power conversion. Virtually every commercial electric motor is driven by a VSI. There is a need for smaller and more efficient drives in high performance applications that is dictating unprecedented power …
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Improvements in direct torque control of induction motors
… the three-level Voltage Source Inverter (VSI). This type of VSI can deliver an increased number of voltage vectors when compared to the standard two-level VSI, and this feature enhances the possibilities of the controller when selecting the output voltage vector to be applied to the motor. …
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On Methodology for Verification, Validation and Uncertainty Quantification in Power Electronic Converters Modeling
… model of a three-phase Voltage Source Inverter (VSI) is quantitatively assessed following the proposed procedure. Accordingly, this thesis describes the hardware design and development of the switching model of the three-phase VSI.
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Exploring Green industrial policy in South Africa through the lens of vertically specialized industrialization
… of Vertically Specialized Industrialization (VSI) as outlined by Milberg, Jiang, and Gereffi as the basis for assessing firm-level governance strategies. The research was performed through semi-structured telephonic interviews with senior level staff at renewable energy firms and …
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Comprehensive optimization and practical design of power electronic systems under multiple competing performance demands
… regulator (VR) and voltage sourced inverter (VSI) design, both of which exemplify power electronic systems under several competing performance demands. A single-objective, multi-constraint structure ensures that all specifications are treated with equal priority, and that no pass-or-fail …
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Multivariate control charts for the mean vector and variance-covariance matrix with variable sampling intervals
… are investigated. A variable sampling interval (VSI) feature is considered in these charts. Two basic approaches for using past sample information in the development of multivariate control charts are considered. The first approach, which is called the combine-accumulate approach, reduces each …
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3-Phase gate-turn off thyristor inverter
… Motor driven by a Voltage Source Inverter (VSI) are studied. A full 3-phase Variable Speed Drive (VSD) and its controller have been designed, constructed and tested. Gate Turn-Off Thyristors (GTO's) are used as the main switching elements in the Inverter stage of the Drive. The drive …
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Typical and Atypical Acquisition of Mathematics, Reading, and Writing: Cognitive Profiles in Early Development
… indexes of Working Memory (WMI), Visual Spatial (VSI), Verbal Acquisition (VAI), Verbal Comprehension (VCI), and Nonverbal (NVI) were utilized as proxies. The selection of these cognitive variables was based on the existing literature in elementary school-age children and SLDs. As hypotheses, …
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Frequency Control of Wind and PV Based Isolated Microgrid
… voltage output of the voltage source inverter (VSI) connected with the DC battery. The better control performance can be obtained by using PR controller which easily tracks reference signal and eliminates steady state error in resonant frequency. The traditional droop control method is applied …
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Variable sampling interval control strategies for a process control problem
… to take the next sample. The performance of the VSI scheme is compared to the performance of the FSI scheme in terms of the percentage reduction in cost. Also, the effects of the cost combinations and the observation errors on the VSI and FSI are studied.
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Development of pulse-width-modulation techniques for multi-phase and multi-leg voltage source inverters
… a single multi-phase voltage source inverter (VSI). Various pulse width modulation (PWM) schemes have been developed for multi-phase machines with concentrated and distributed windings, utilising both carrier-based PWM and space vector PWM (SVPWM) approaches. However, no systematic analysis has …
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