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The aim of this article is to develop a simplified equivalent dynamic model capable to capture the transient behavior of a gas-fueled co-generator. To comply with this exigency, an online identification methodology based on the sensitivity theory in conjunction with the Lyapunov function is adopted. By this methodology, stable solutions can be achieved in the online environment, renewing the parameters of the model at every change occurring on the physical system. In order to investigate the effectiveness of the proposed methodology in deriving a simplified dynamic model, several simulations and experimental tests were performed on the Prince Lab microgrid located at the Polytechnic University of Bari. [ABSTRACT FROM AUTHOR]

This paper deals with the development of an on-line identification method for deriving simplified dynamic models. The practical applicability of the derived algorithm has been tested on the Capstone C30 microturbine installed at the Polytechnic University of Bari, Italy. For this purpose, a second order model has been identified by adopting the sensitivity theory involving the Lyapunov function giving rise to stable solutions in the on-line environment, renewing model parameters at every changes occurring on the physical system. This characteristic can be fruitfully adopted for implementing actual models in time domain simulators, giving rise to accurate results even if some internal parameters change. In order to investigate on the effectiveness of the proposed methodology in deriving a simplified dynamic model, several simulations and experimental tests were conducted in the Prince Lab of the Polytechnic University of Bari. The good agreement between simulations and laboratory tests confirm the validity and the applicability of the proposed methodology. [ABSTRACT FROM AUTHOR]

This paper proposes a decentralized nonlinear autoadaptive controller for reducing system losses by the optimal management of the reactive power supplied by the inverters of photovoltaic (PV) units. This ancillary service can be furnished on the base of standard needs or on voluntary basis. The control design is based on an optimization procedure involving the sensitivity theory in conjunction with the Lyapunov function and provides control laws acting as references of the PV inverter local controller. PV inverters must operate in a decoupled manner in order to provide the reactive power imposed by the control law and to transfer the active power produced by PV modules. The experiences and results conducted in an indoor laboratory as well as on an actual distribution network managed by ENEL Distribuzione S.p.A. demonstrate its effectiveness in reducing system losses. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a novel methodology for evaluating the external equivalent model of a distributed network is presented. The proposed method is based on a non-linear parameter identification process which involves an artificial dynamic system, whose dynamics are explicitly designed to be stable by adopting the Lyapunov theory. This dynamic identification method is competitive with existing reduction methods, since it does not require system linearization or any a priori information about the system under study. Few measurements at boundary nodes are required to obtain the essential information regarding the external system. Even if these measurements are strongly corrupted by noise, the algorithm is quite insensible to it. Due to its ability to be auto-adaptive at any changes in the system operating conditions and to its great speed convergence, the identification procedure can be usefully applied for real-time applications. [Copyright &y& Elsevier]