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1 – 10 of 12This paper presents a VHDL‐AMS based genetic optimisation methodology for fuzzy logic controllers (FLCs) used in complex automotive systems and modelled in mixed physical domains…
Abstract
Purpose
This paper presents a VHDL‐AMS based genetic optimisation methodology for fuzzy logic controllers (FLCs) used in complex automotive systems and modelled in mixed physical domains. A case study applying this novel method to an active suspension system has been investigated to obtain a new type of fuzzy logic membership function with irregular shapes optimised for best performance.
Design/methodology/approach
The geometrical shapes of the fuzzy logic membership functions are irregular and optimised using a genetic algorithm (GA). In this optimisation technique, VHDL‐AMS is used not only for the modelling and simulation of the FLC and its underlying active suspension system but also for the implementation of a parallel GA directly in the system testbench.
Findings
Simulation results show that the proposed FLC has superior performance in all test cases to that of existing FLCs that use regular‐shape, triangular or trapezoidal membership functions.
Research limitations
The test of the FLC has only been done in the simulation stage, no physical prototype has been made.
Originality/value
This paper proposes a novel way of improving the FLC's performance and a new application area for VHDL‐AMS.
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Keywords
Redha Benachour, Saïda Latreche, Mohamed El Hadi Latreche and Christian Gontrand
The present work aims to explain how the nonlinear average model can be used in power electronic integration design as a behavioral model.
Abstract
Purpose
The present work aims to explain how the nonlinear average model can be used in power electronic integration design as a behavioral model.
Design/methodology/approach
The nonlinear average model is used in power electronic integration design as a behavioral model, where it is applied to a voltage source inverter based on IGBTs. This model was chosen because it takes into account the nonlinearity of the power semiconductor components and the wiring circuit effects, which can be formalized by the virtual delay concept. In addition, the nonlinear average model cannot distinguish between slow and quick variables and this is an important feature of the model convergence.
Findings
The paper studies extensively the construction of the nonlinear average model algorithm theoretically. Detailed explanations of the application of this model to voltage source inverter design are provided. The study demonstrates how this model illustrates the effect of the nonlinearity of the power semiconductor components' characteristics on dynamic electrical quantities. It also predicts the effects due to wiring in the inverter circuit.
Research limitations/implications
More simulations and experimental analysis are still necessary to improve the model's accuracy, by using other static characteristic approaches, and to validate the applicability of the model to different converter topologies.
Practical implications
The paper formulates a simple nonlinear average model algorithm, discussing each step. This model was described by VHDL‐AMS. On the one hand, it will assist theoretical and practical research on different topologies of power electronic converters, particularly in power integration systems design such as the integrated power electronics modules (IPEM). On the other hand, it will give designers a more precise behavioral model with a simpler design process.
Originality/value
The nonlinear average model used in power electronic integration design as behavioral model is a novel approach. This model reduces computational costs significantly, takes physical effects into account and is easy to implement.
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S. Schulte, C. Kaehler, C. Schlensok and G. Henneberger
To present a new approach for improvement and optimization of synchronous claw‐pole alternators without changing the general machine design.
Abstract
Purpose
To present a new approach for improvement and optimization of synchronous claw‐pole alternators without changing the general machine design.
Design/methodology/approach
Various changes on the magnetically relevant parts of the machine design have been discussed formerly to achieve improved electromagnetic and acoustic behavior. The electrical part of the machine is considered in this paper, varying the stator winding arrangement to achieve optimized behavior.
Findings
Provides information about motivation and the methodology of the optimization process. Presents the entire analysis, covering idea, technical and computational implementation as well as verification.
Research limitations/implications
It describes a method based on the utilization of specific, partly self‐generated software, which perhaps limits its usefulness if mentioned tools are unavailable. However, the presented basic method is to be used generally.
Originality/value
This paper presents a promising approach to further optimize the design of synchronous claw‐pole alternators without major changes in the machine design.
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This paper presents a prediction on the impact of technology scaling on phase‐locked loop (PLL) performance behaviour. Power and maximum operating frequency of an Analogue PLL and…
Abstract
Purpose
This paper presents a prediction on the impact of technology scaling on phase‐locked loop (PLL) performance behaviour. Power and maximum operating frequency of an Analogue PLL and a Type II phase‐frequency detector (PFD)‐based PLL from which the behaviours of other PLLs derived from the two architectures can be estimated, are analysed and their future behaviours as a function of technology are predicted.
Design/methodology/approach
Analogue models were developed and Mentor Graphics VHDL‐AMS mixed‐signal simulations were performed on the two PLL architectures. Behavioural power and frequency equations as a function of technology were derived based on thorough data and graphical analyses.
Findings
A prediction of PLL frequency and power dissipation as a function of technology for two main PLL architectures.
Research limitations/implications
The parameters in each equation derived should include other contributing factors as well as other design approaches such as multi‐VDD, multi‐Vth, etc. future work should also include prediction of jitter and phase noise for the two main PLL topologies.
Originality/value
This paper is of high significance in PLL design. The predicted equations could be used to reduce a major portion of a PLL designers' design time when choosing a PLL topology, and help them predict the impact of technology on the performance of the chosen architecture.
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Andrzej Napieralski, Malgorzata Napieralska, Michal Szermer and Cezary Maj
The purpose of this paper is to show the evolution of microsystems together with modeling methods in the space of dozen years as a result of finished research in the frame of…
Abstract
Purpose
The purpose of this paper is to show the evolution of microsystems together with modeling methods in the space of dozen years as a result of finished research in the frame of several projects.
Design/methodology/approach
In this paper several approaches are presented. First, microsystems were built in multi project wafer technology. They were demonstrators like micromotor, micromirrors or micropumps modeled using dedicated design tool. A multi purpose chip was also designed using HDL description and FEM simulations. The next project concerned chemical sensors, where specialized models were developed and implemented in VHDL‐AMS in order to perform multidomain behavioral simulations. Dedicated tools were also developed for medical applications.
Findings
The evolution of MEMS technology is strictly connected with simulation and modeling methods. The success and short time to market need fast and accurate simulation methods. This paper shows that the approach depends on application. Moreover, it is connected with the access to the technology.
Originality/value
This paper presents a brief overview on projects performed in DMCS‐TUL department. It shows the evolution of modeling methods and technology used in developing and fabrication of microsystems for various applications.
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Ling Xuqiang, Huang Xiaodong, Li Bohu and Chai Xudong
Complex system modeling requires not only understanding of modeling framework but also domain knowledge of the system. The purpose of this paper is to present an approach which…
Abstract
Purpose
Complex system modeling requires not only understanding of modeling framework but also domain knowledge of the system. The purpose of this paper is to present an approach which separates the domain knowledge from the modeling framework with different views.
Design/methodology/approach
By establishing the mechanism of association and fusion among the views, the description and characterization of system from different aspect and point of view can form a complete system model. Based on the approach, a modeling and simulation (M&S) platform named SimFaster is developed. Modeling environment and simulation engine are the most important parts of the platform. The modeling environment provides multi‐views and multi‐layers to help the developers to modeling the structure, layers, composition, behavior, and interactions of an application system. The simulation engine provides mechanism of integration and interaction for components and objects, and provides runtime support for the concepts and terms from modeling environment. The simulation engine organizes the objects in the memory of distributed system as reflective object database system, so it is repository centered architecturally.
Findings
Based on the approach of multi‐views modeling, the platform is a flexible framework and supports top‐down design, model reuse and interoperation, dynamic refinement of models, corporative design among different users in different stages, and the rebuilt of application rapidly.
Research limitations/implications
This paper deals with high‐level models of the complex systems.
Practical implications
This platform helps to design, modeling, and simulation complex system (especially for weapon combat system). It can participate into all the stages of the development of complex product/system, and can support the validation, refinement, optimization of models, and systems.
Originality/value
This paper presents a multi‐views modeling approach for the modeling of complex system.
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B. Delinchant, D. Duret, L. Estrabaut, L. Gerbaud, H. Nguyen Huu, B. Du Peloux, H.L. Rakotoarison, F. Verdiere and F. Wurtz
This paper is a synthesis paper which seeks to discuss an optimisation framework using software components, which is a new emerging paradigm in computer science.
Abstract
Purpose
This paper is a synthesis paper which seeks to discuss an optimisation framework using software components, which is a new emerging paradigm in computer science.
Design/methodology/approach
The goal of this paper is to show the efficiency of the software component approach for the implementation of optimisation frameworks for engineering systems in general, and electromagnetic systems in particular.
Findings
This paper highlights the component standard, a generator based on analytical expressions of the system, and an optimization service. References and examples show application in the area of electromagnetic components and systems.
Practical implications
This paper presents CADES, a framework dedicated to system design, based on optimization needs. The framework is defined with a standard implementing the software component paradigm and a pattern to use it. Indeed, this pattern details how to create and use a component (the model of the device to design).
Originality/value
This paper shows how the new emerging paradigm of software components can be used for building new generations of optimisation environment allowing capitalisation and reuse by combination of software components containing models and optimisation algorithms.
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Stephan Schulte and Kay Hameyer
The paper aims to provide an approach to actively decrease the radiation of acoustic noise in synchronous machines.
Abstract
Purpose
The paper aims to provide an approach to actively decrease the radiation of acoustic noise in synchronous machines.
Design/methodology/approach
Splitting regular three‐phase windings of synchronous machines into two independent three‐phase systems allows for an active influence of the current waveform if both winding systems are mutually displaced against each other. The harmonics content of each phase‐current varies due to the mutual inductive coupling with participating currents of both systems. Therefore, the ensuing force‐density distribution on the stator teeth varies accordingly. Resulting structure dynamics and furthermore the radiation of relevant harmonics of the acoustic noise are based on the mechanical excitation of considered force‐density distributions.
Findings
Configurations of mutual displacement of phase windings of both winding systems with significant decrease of mechanical deformation and emitted acoustic noise are found. Simulation methods to entirely describe and prove the behavior described are developed.
Research limitations/implications
The proposed approach is developed for a particular synchronous machine. Other machine types are conceivable for analysis in the same manner. Tools need to be adapted. Universal and reliable statements regarding acoustic behavior depend on the mechanical restraint of the machine and may therefore vary.
Practical implications
Active force‐density distribution is used for the noise reduction of alternators in vehicle applications. Additionally, wind‐power generators are considered for the application of split stator winding systems to actively counteract inhomogeneous force distributions on the rotor, evoked by stalling of the propeller blades during pole passing.
Originality/value
Active force‐density modification by stator winding modifications allows for the decrease of noise radiation of electrical machines with rotating‐field windings. Innovative simulation methods developed may now replace prototyping partially.
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Keywords
Abstract
Details
Keywords
Mounir Bouzguenda, Tarek Selmi, Adel Gastli and Ahmed Masmoudi
The purpose of this paper is to study the problem of the leakage currents in transformerless inverter topologies. It proposes a novel topology and how important the adopted…
Abstract
Purpose
The purpose of this paper is to study the problem of the leakage currents in transformerless inverter topologies. It proposes a novel topology and how important the adopted control strategy on the power quality produced by the inverter.
Design/methodology/approach
The paper presents an investigation of a novel transformerless inverter topology. It adopted a control strategy in which the DC source is disconnected from the inverter when the zero vectors of the control are applied. By using such control strategy, the electrical efficiency of the whole system was improved and the leakage current was significantly reduced.
Findings
The paper provides a solution to minimize the leakage current in transformerless inverter topologies. Besides, the problem of zero-crossing distortions was totally eliminated.
Research limitations/implications
Because of the high conversion ratio of the boost converter, the efficiency of the whole system needs to be enhanced.
Practical implications
The paper includes the experimental results of the proposed topology which are in good match with the simulation results.
Originality/value
This paper identifies a need to study the leakage current phenomena in transformerless inverter topologies.
Details