A switched inertance hydraulic system uses a fast switching valve to control flow or pressure and is potentially very efficient as it does not rely on dissipation of power by throttling. This article studies its performance using an analytical method which efficiently describes the system in the time domain and frequency domain. A lumped parameter model and a distributed parameter model have be...

Port-based network modeling of (lumped-parameter) physical systems leads directly to their representation as port-Hamiltonian systems which are an important class of passive state-space systems. At the same time modeling of physical systems often leads to high-dimensional dy namical models. State-space dimensions are enormously high as well if distributed-parameter models are spatially discreti...

This paper deals with the model predictive control of processes. The new step is the use of a distributed parameter system instead of a lumped parameter system. The internal model control structure is also used to solve the trajectory tracking problem. The internal model is obtained from the linearization of the initial set of nonlinear partial differential equations about the desired trajector...

Multidimensional systems describe relations between signals depending on two or more independent variables, like time and space. They are also called distributed parameter systems. The only conventional model for their description are partial diierential equations. This is in contrast to onedimensional (lumped parameter) systems, where a variety of diierent models including transfer functions i...

A disturbance observer based tracking control algorithm is presented in this paper. The key idea of the proposed method is that the plant nonlinearities and parameter variations can be lumped into a disturbance term. The lumped disturbance signal is estimated based on a plant dynamic observer. A state observer then corrects the disturbance estimation in a two-step design. First, a Lyapunov-base...

ions at multiple sites (Efstratiadis et al., 2008). Distributed schemes are founded on small-scale physics, which, in theory, allows for getting all parameter values from field data, thus avoiding calibration effort. However, the lack of extended field measurements when dealing with real systems, in addition to scale-compatibility problems, leads to an intermediate strategy, aiming to optimize ...

The paper presents a critical appraisal of existing methods for modelling and simulation of CNC machine tool feed drives. Their goal is the development of mathematical models which adequately replicate the dynamic behaviour of the actual machines. The advantages and disadvantages of lumped parameter models and modular approach are discussed and the suitability of mixed, hybrid, distributed-lump...

This paper presents the responses of the railway vehicle and track components in terms of contact forces and displacements. The considered vehicle model is a five-DOF pitch-plane lumped parameter quarter car model supported on two-dimensional track systems comprising three layers. The car body is linked with the vehicle bogie through secondary suspension springs and damper elements, which is fu...

The frequency spectrum of an external system used in the simulation of electromagnetic transients shows many peaks due to resonance effects of the leading transmission lines. Therefore, the two-level equivalent we developed contains simplified lines for the leading part of the system and lumped elements represented by rational functions as a correction for the rest of the external system. This ...