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Transient simulation programs, either nodal analysis-based electromagnetic transient program (EMTP-like) or state-variable-based, are used very extensively for modeling and simulation of various power and energy systems with electrical machines. It has been shown in the literature that the method of interfacing machine models with the external electrical network plays an important role in numerical accuracy and computational performance of the overall simulation. This paper considers the state-variable-based simulation packages, and provides a constant-parameter decoupled RL-branch equivalent circuit for interfacing the ac induction and synchronous machine models with the external electrical network. The proposed interfacing circuit is based on the voltage-behind-reactance formulation which has been shown to have advantageous properties. For the synchronous machines, this paper describes both implicit and explicit (approximate) interfacing methods. The presented case studies demonstrate the advantages of using the proposed interfacing method over the traditional qd-models that are conventionally used in many simulation packages. [ABSTRACT FROM AUTHOR]

In this paper, a numerical simulation was carried out to analyze the effect of diffusion charging on collection efficiency of a wire-plate electrostatic precipitator (ESP). The gas flow field, the electric field, and the particle field with diffusion charging considered were included in the numerical model, which was implemented by using the commercial FLUENT software. Collection efficiency was calculated by using the Deutsch–Anderson equation, in which the parameters were provided from the numerical solutions. The simulated results indicate that the effect of diffusion charging on the wire-plate ESP particle collection increases with the decreasing particle diameter, as well as applied potential, particularly for PM10. Moreover, with the increasing applied potential, collection efficiency of PM10 is obviously improved, and the effect extent first increases and then decreases with particle size increasing, but also, the size range of particle, which is significantly affected by the diffusion charging, becomes smaller. As gas velocity becomes higher, the effect of diffusion charging on grade efficiency also becomes more obvious, and the affected range of particle size gets much larger, however, at the price of grade efficiency decreasing. Using collection efficiency as reference variable of judgment, instead of particle charge, may lead to a more accurate estimation of the aforementioned size range, which can provide a great help in the further analysis of fine particle collection. [ABSTRACT FROM PUBLISHER]

This correspondence paper presents an algorithm in which the independent components of link lengths are used as a medium to analyze the forward kinematics of a six-degree-of-freedom Stewart platform. The link lengths are firstly transformed into independent components through independent component analysis. Then, the value of positional variables is computed by using the Nelder–Mead algorithm by taking advantage of the relationships between the independent components and the positional variables. Simulations have been conducted to test the proposed algorithm. The experimental results show that the proposed algorithm can achieve a better performance than the other published algorithms. [ABSTRACT FROM PUBLISHER]

This paper presents for the first time the transient simulation of the 3-D \TE34, 19 mode converter with surface deformation. The simulation results were obtained by solving the Maxwell equations directly on a 3-D domain with a discontinuous Galerkin method. The presented full-wave simulation was possible only through the use of an advanced highly scalable numerical method operating on a large-scale high-performance computing system. Moreover, the properties of the Maxwell solver with respect to accuracy and computation time are discussed for the application to a smooth-wall \TE34, 19 waveguide where an analytical solution is available. [ABSTRACT FROM PUBLISHER]

An exact analytical solution for the via-plate capacitance in multilayer printed-circuit board (PCB) structures is presented. The formulation is based on Laplace's equation for the static electric potential within the via-plate region, which is electrically small for a large frequency range. The potential distribution is determined by the separation of Laplace's equation in cylindrical coordinates for the three subdomains: via barrel and pad, antipad, and the plate region. It is shown that the unknown via-plate capacitance is determined by only one single coefficient of the resulting linear equation system. The influence of additional via pads is readily included. The results are compared with previously published approaches and validated by 2-D static, as well as by 3-D full-wave numerical simulations. [ABSTRACT FROM AUTHOR]

In the work presented here, we contribute to two extensions to the sequential Monte Carlo (SMC) or particle filtering approach for on-line sinusoidal frequency tracking in [1]. First, we propose to employ multiple dynamical models for better parameter tracking at different times in the light of observations as the unknown frequency and its rate of change are time varying. Second, \alpha-stable noise, which is a generalization of the traditional Gaussian process, is considered as the additive disturbance in the observed signal. In other words, the proposed method is required to estimate both the unknown time-varying frequency and the characteristics of the \alpha-stable process. According to computer simulation results, it is found that the proposed multiple-model method performs better in terms of smaller estimation error than the case when only a particular single model is employed. [ABSTRACT FROM PUBLISHER]

We present a hybrid system-level modeling and simulation methodology by combining numerical macromodels with parameterized lumped-element behavioral models for structurally complex microelectromechanical systems (MEMS). We decompose the MEMS into several functional components. For those components with complex geometry and boundary conditions, we model them using numerical macromodels, whereas for those with simple geometry, we model them using parameterized lumped-element behavioral models. Both models are represented by the same syntax and similar equation forms to ensure the compatibility. Afterward, the hybrid numerical macromodels and parameterized behavioral models are inserted into the same simulator and then interconnected to each other according to the original topography of the MEMS for system-level simulation. As one of the key technologies of the proposed methodology, macromodeling has been improved in two aspects. First, macromodeling for the component with dynamic boundary condition is achieved by combining modal analysis with a novel iterated improved reduced system method. Second, angular parameterization for the components with the same geometry but different initial orientation is achieved by the matrix coordinate transformation. A z-axis micromachined gyroscope is used to demonstrate the proposed methodology. Simulation results show that the method can efficiently support the design for structurally complex MEMS. \hfill[2010-0007] [ABSTRACT FROM AUTHOR]

A second-order multi-point Krylov subspace projection based model order reduction process for electromagnetic simulations is presented. The electromagnetic setup is converted to a second-order model—susceptance element based equivalent circuit. The state-space representation of this equivalent circuit is suitably reduced through a model order reduction process, where the recursive calculation of the projection matrix is done through a preconditioned iterative method. Issues concerning the passivity of the reduced system are discussed. The single-point and multi-point schemes are validated through numerical examples. The second-order multi-point algorithm for the reduction process is shown to be advantageous in matching response curves exhibiting complex behavior. [ABSTRACT FROM PUBLISHER]