Steady-State Sensitivities of Marine Propulsion Control Techniques

2021 ◽  
Vol 32 (3) ◽  
pp. 543-562
Author(s):  
Matheus C. Hidalgo ◽  
Fuad Kassab Junior
Keyword(s):  
Steady State ◽  
Control Techniques ◽  
Marine Propulsion ◽  
Propulsion Control

Improved Load Sharing Control Techniques for Inverters used in a Microgrid

2009 ◽  
Vol 10 (1) ◽  
Author(s):  
Wei Yao ◽  
Zhaoming Qian
Keyword(s):  
Steady State ◽  
Transient Response ◽  
Single Phase ◽  
Load Sharing ◽  
Power Sharing ◽  
Experimental Results ◽  
Control Technique ◽  
Transient Performance ◽  
Control Techniques ◽  
Control Scheme

In this paper, an improved load sharing control scheme is presented, which is able to improve the transient response and power sharing accuracy of parallel-connected inverters used in microgrid. It also shows how the improved droop method can be easily adapted to account for the operation of parallel-connected inverters, providing good performance under the variation and disturbance of loads, as well as achieving good steady-state objectives and transient performance. Two DSP-based single-phase Microgrid inverters are designed and implemented. Simulation and experimental results are all reported, confirming the validity of the proposed control technique.

CFD-Based Simulation of Inlet Unstart Phenomena: Toward Supersonic Inlet Flow Control Techniques

2003 ◽  
Author(s):  
Daniel N. Miller ◽  
Brian R. Smith
Keyword(s):  
Steady State ◽  
Flow Control ◽  
High Speed ◽  
Steady State Solution ◽  
Accurate Solution ◽  
Back Pressure ◽  
Inlet Flow ◽  
Control Techniques ◽  
Contour Plots ◽  
Inlet Unstart

A time-accurate, full Navier-Stokes, Computational Fluid Dynamics (CFD) analysis of a back-pressure-induced, high-speed inlet unstart event was conducted. The objective was to identify visible and quantitative flowfield characteristics prior to and during an unstart event. The CFD-based investigation was conducted on a 2-D wind-tunnel model geometry of a forebody and inlet at a freestream Mach number of 5. A sequence of steady-state solutions were run to map the inlet flowfield response to subsequent increases in back-pressure from a design value up to the point of imminent unstart. A time-accurate solution commenced, using the final steady-state solution as the initial condition. The CFD-derived inlet flowfield contour plots compared well with test-derived color schlieren images, while predictions for steady-state and transient wall pressure compared reasonably with test data. A CFD-based study of inlet flow control techniques will follow.

scholarly journals Propeller Load Modelling In The Calculations Of Marine Shafting Torsional Vibrations

2021 ◽  
Vol 93 (6s) ◽  
pp. 204-216
Author(s):  
Nenad Vulić ◽  
◽  
Karlo Bratić ◽  
Branko Lalić ◽  
Ladislav Stazić ◽  
...  
Keyword(s):  
Steady State ◽  
Dynamic System ◽  
Simulation Modelling ◽  
Analytical Models ◽  
Torsional Vibrations ◽  
Class Society ◽  
Marine Propulsion ◽  
Maritime Studies ◽  
Calculation Results ◽  
Service Loading

Technical rules of IACS classification societies require that calculations of torsional vibrations for all propulsion shafting systems, as well as for shafting systems of auxiliary machinery above certain power, shall be prepared, submitted and validated for the vessels requesting the class certificate. These calculations may be approached either by conventional analytical models based upon systems of ordinary differential equations describing the actual dynamic system, or by simulation modelling of the same dynamic system. The research team of the authors has been established within the R&D Centre of the Faculty of Maritime Studies at Split. The aim of the team is to investigate possibilities and constraints for implementation of the SimulationX software to the simulation modelling of torsional vibrations of dynamic systems, such as marine propulsion and auxiliary shafting. In general, results of these calculations depend upon the concept of the system (two-stroke vs. four-stroke Diesel engine, torsional vibration damper present or not, flexible coupling present or not, fixed pitch or controllable pitch propeller, etc.), dimensions of components, their material properties and service loading. Propeller load modelling within the service loading is very important. Even the preliminary research results show that its simplest part, i.e. the steady-state propeller loading of the system without taking excitations into account, may have a significant influence on the results of torsional vibrations calculation and consequently even to their acceptability by the class society. For this reason, the present paper describes two different ways to express propeller steady-state loading formulations, as prescribed by different sources and authorities, as well as their influence on the torsional vibrations calculation results and meeting the criteria of the IACS Unified Requirements, presenting them in a real verified and validated case study.

OPENDSS MODELING FOR STEADY-STATE ANALYSIS OF DISTRIBUTED GENERATION CONTROL TECHNIQUES

2018 ◽  
Author(s):  
MATHEUS DE OLIVEIRA AFONSO ◽  
BRUNO DE MELLO LAURINDO ◽  
BRUNO WANDERLEY FRANÇA ◽  
RENAN SILVA MACIEL ◽  
MAURÍCIO AREDES
Keyword(s):  
Steady State ◽  
Distributed Generation ◽  
Steady State Analysis ◽  
Control Techniques ◽  
Generation Control ◽  
State Analysis

Steady-State and Transient Operations of a Euro VI 3.0L HD Diesel Engine with Innovative Model-Based and Pressure-Based Combustion Control Techniques

2017 ◽  
Vol 10 (3) ◽  
pp. 1080-1092 ◽  
Author(s):  
Ezio Spessa ◽  
Stefano D'Ambrosio ◽  
Daniele Iemmolo ◽  
Alessandro Mancarella ◽  
Roberto Vitolo ◽  
...  
Keyword(s):  
Steady State ◽  
Diesel Engine ◽  
Combustion Control ◽  
Control Techniques ◽  
Model Based ◽  
Innovative Model ◽  
Transient Operations

scholarly journals Exploring the Brain-to-Brain interaction at a distance: a global or differential relationship?

2017 ◽  
Author(s):  
William Giroldini ◽  
Luciano Pederzoli ◽  
Marco Bilucaglia ◽  
Elena Prati ◽  
Patrizio Tressoldi
Keyword(s):  
Steady State ◽  
Long Distance ◽  
Stimulus Interval ◽  
Control Techniques ◽  
Inter Stimulus Interval ◽  
Mind Control ◽  
Correlation Strength ◽  
The Relationship ◽  
The Brain ◽  
Differential Relationship

Backgound: The main objective of this exploratory study was a confirmation of the results obtained by Giroldini et al, 2016, relative to the possibility of identifying a long-distance connection between the EEG activities of two totally isolated subjects, one of whom was stimulated with light and sounds. In this new study we have used the method of the steady-state stimulus (visual and auditory) given at the frequencies of 10, 12 and 14 Hz in order to answer the following questions:- What is the relationship between the power of the EEG response in the stimulated partner and that of the other isolated partner?- Is the relationship between the EEG activities of the stimulated and the isolated partner global (i.e., an undifferentiated response), or is it differentiated and thus displays variations depending on the characteristics of the stimulation applied to the stimulated partner?Methods: Five adults chosen for their experience in mind control techniques and their mutual friendships took part in this study. Each participant took turns in being both the stimulated partner and the isolated non-stimulated partner with each of the others, making a total of 20 pair combinations.The stimulated partner received three blocks of 32 visual-auditory stimulations lasting 1 second modulated at 10 Hz, 12 Hz, and 14 Hz respectively, with a constant inter-stimulus interval of 4 seconds.The EEG activity of each pair was recorded at 128 samples/sec over 14 channels and analyzed by measuring traditional steady-state potentials and the Pearson’s linear correlation between all possible signal pairs with an innovative algorithm.Results: From the results of twenty pairs of subjects, we found an overall increase in the correlation among the EEG channels of the isolated partners, therefore confirming the previous research.Furthermore, we did not find any correlation between the correlation strength among the EEG channels of the stimulated partner and that observed in the non-stimulated partner, suggesting that this physical characteristic cannot be transferred between isolated partners; but we did find that the correlation among the EEG channels of the isolated distant partners changed not only globally, but also when the frequencies perceived by the stimulated partners were outside the Alpha band, suggesting that this neurophysiological mental connection at a distance may be differentiated.

scholarly journals Governing Gas Turbine Engines for Marine Propulsion: Power Versus Speed Control

1968 ◽  
Author(s):  
D. A. O’Neil
Keyword(s):  
Gas Turbine ◽  
Speed Control ◽  
Gas Turbine Engine ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Turbine Engine ◽  
Marine Propulsion ◽  
Propulsion Control ◽  
Control Methodology ◽  
Propulsion Power

This paper examines typical shipboard operational requirements, conventional marine propulsion control methodology, and the related merits of power and speed governing for the aircraft derived marine gas turbine engine applications of the future.

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