Exchange Platform

Author: n.sene
Type: Publication
Date: 2015-04-02

Power system islands, autonomous microgrids and relevant instrumentation

Description:
Unplanned power system islanding is usually seen as a major risky operating condition and specific countermeasures are applied in order to avoid it. However the capability of voluntary disconnection f... see morerom the external grid and autonomous operation is often a requirement for some industrial power systems and power plants. The panel session at the 2012 IEEE Innovative Smart Grid Technologies Conference on
“Power system islands, autonomous microgrids and relevant instrumentation” aims at providing an occasion to exchange ideas and experiences in order to envisage situations in which voluntary power system islanding may be useful and to define the instrumentation required for a reliable operation in islanded conditions. This paper, provided by the organizers, reviews some activities recently carried out on this topic at their institution.

Authors: A. Borghetti, L. Peretto

Tag(s): Power systems islanding, microgrids, measurements.

Author: n.sene
Type: Publication
Date: 2015-04-01

DISPERSED ENERGY RESOURCES SCHEDULING FOR THE INTENTIONAL ISLANDING OPERATION OF DISTRIBUTION SYSTEMS

Description:
The paper presents an algorithm for the automatic optimal scheduling of dispersed energy resources (DERs) and of under-load tap changers (ULTCs) position. The aim of the scheduling problem consists in... see more the minimization of the voltage deviations with respect the rated value, of the DERs production deviation with respect the maximum efficiency point, and of the network losses.
The system incorporates also a procedure to facilitate the intentional islanding maneuver of the distribution network. The adopted approach is based on iterative solution of linear-constrained multi-objective optimization problems. The nonlinear power flow relationships are linearized by means of the calculation of sensitivity coefficients to small variations of the control variables (namely, controllable DERs power outputs and ULTCs positions). The algorithm is implemented in Matlab environment to exploit different solvers and suitably interfaced with EMTP-RV for three-phase power flow detailed calculations. In particular, two optimization solvers are adopted: the least square method and the goal attainment approach. The relevant results are compared using the IEEE 34-node distribution feeder as test case.

Authors: A. Borghetti, C.A. Nucci, M. Paolone, M. Bosetti

Tag(s): Dispersed generation, active distribution networks, islanding operation.

Author: n.sene
Type: Publication
Date: 2015-04-01

Analysis of black-startup and islanding capabilities of a combined cycle power plant

Description:
The paper presents the analysis of black-startup and islanding capabilities of an 80 MW combined cycle power plant. The analysis is carried out by means of a computer dynamic simulator suitably develo... see moreped in the EMTP-RV simulation environment in order to represent both the power plant and the local network with the relevant loads. The paper describes the main characteristics of the implemented models and presents the analysis of transients due to both energization and islanding manoeuvres. The former simulations aim at verifying the feasibility of the energization of the path from a turbo gas unit, with autonomous black-start capabilities, to the local distribution network loads. The latter simulations allow the analysis of different islanding strategies for rather large levels of power exported to the external transmission network.

Authors: A. Borghetti, C.A. Nucci, M. Paolone, M. Bosetti, G. Ciappi, A. Solari

Tag(s): black-startup, islanding, combined cycle, power plant, energization

Author: n.sene
Type: Publication
Date: 2015-04-01

Parameters Identification of a Power Plant Model for the Simulation of Islanding Transients

Description:
The paper presents a procedure for parameter identification along with its application to the model of a combined cycle power plant that includes the surrounding electrical network, built for the anal... see moreysis of islanding maneuvers transients. The paper illustrates both the power system computer model, implemented within the EMTP-RV simulation environment, and the developed identification procedure based on the interface between the developed model and Matlab. The parameter identification procedure is applied to experimental transient recordings that make reference to a similar power plant.

Authors: A. Borghetti, C.A. Nucci, M. Paolone, M. Bosetti

Tag(s): Islanding, Identification, Power Plant