Optimal Multisine Probing Signal Design for Power System Electromechanical Mode Estimation

This paper proposes a methodology for the design of a probing signal used for power system electromechanical mode estimation. Firstly, it is shown that probing mode estimation accuracy depends solely on the probing signal’s power spectrum and not on a specific time-domain realization. A relationship between the probing power spectrum and the accuracy of the mode estimation is used to determine a multisine probing signal by solving an optimization problem. The objective function is defined as a weighting sum of the probing signal variance and the level of the system disturbance caused by the probing. A desired level of the mode estimation accuracy is set as a constraint. The proposed methodology is demonstrated through simulations using the KTH Nordic 32 power system model

Journal Staff

This paper presents the implementation of three different types of Power System Stabilizers (PSS) and a Static Var Compensator with a supplementary Phasor Power Oscillation Damper (POD) control for real-time simulation. The Klein-Rogers-Kundur model is used as test case and the PSS and Phasor-POD’s performance is evaluated for both large and small disturbances.  Modeling is performed in the MATLAB/Simulink environment and is executed in real-time using Opal-RT’s eMEGAsim Real-Time Simulator. The simulation results and the developed model will be used to deploy hardware prototype based on embedded controllers to provide power oscillation damping. Real-time software in the loop (SIL) approach is used for validating developed models as a first logical step towards development of a prototype hardware controller.QC 20150311</p

Measurement-based network clustering for active distribution systems

©2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.This paper presents a network clustering (NC) method for active distribution networks (ADNs). Following the outage of a section of an ADN, the method identifies and forms an optimum cluster of microgrids within the section. The optimum cluster is determined from a set of candidate microgrid clusters by estimating the following metrics: total power loss, voltage deviations, and minimum load shedding. To compute these metrics, equivalent circuits of the clusters are estimated using measured data provided by phasor measurement units (PMUs). Hence, the proposed NC method determines the optimum microgrid cluster without requiring information about the network’s topology and its components. The proposed method is tested by simulating a study network in a real-time simulator coupled to physical PMUs and a prototype algorithm implementation, also executing in real time.Peer ReviewedPostprint (author's final draft

International Law and State Socialization: Conceptual, Empirical, and Normative Challenges

This article reports the results from the implementation and testing of a Wide-Area Power Oscillation Damper (WAPOD) controlling a 180 Mvar TCR Static Var Compensator (SVC) installed in the Hasle substation of Norwegian 420 kV transmission grid. The WAPOD uses voltage phase angle signals from two distant locations in the Norwegian grid as inputs to the damping controller. The damping controller modulates the voltage reference set point used by the SVC’s voltage controller, thereby creating a damping effect. The WAPOD is an extension to the existing Power Oscillation Damping (POD) controller that uses local measurements. A switch-over logic allows for the use of no damping control, local damping control or wide-area control. Field tests were performed during November 2011, and involved the disconnection and re-connection of a 420 kV transmission line. The performance of the WAPOD is compared to that of state-of-the-art local Phasor POD, and when no damping control is enabled. The testing results show that the WAPOD performed satisfactorily and according to the design expectations. These results show that the potential flexibility of the WAPOD to choose, among the different PMU signals, those that have the good observability of inter-area modes can be an advantage to the use of local feedback signals for damping control, as it is current practice today. Further testing of this WAPOD with other PMU signals from locations with stronger observability will be helpful to illustrate the advantage of this flexibility.QC 20140512Invited Paper for the Panel Session: “Synchrophasor Measurement Applications in Power Industry to Enhance Power System Reliability”, IEEE PES General Meeting 2012, San Diego, CA.</p

L' evoluzione del mercato agroalimentare italiano dalla fine del 900 ad oggi: verso la sostenibilità

ope

О роли самостоятельной работы при изучении химии на факультете профориентации и довузовской подготовки

ХИМИЯсамостоятельная работаизучени

Rural development and territorial capital in a Hungarian and French region

Voltage-Source Converter-Based High-voltage dc (VSC-HVdc) technology has received growing interest during recent years due to its benefits for separated active and reactive power control. Before the installation of VSC-HVdc links, different simulation-based studies need to be performed, usually by different parties and using different electromagnetic transient (EMT) simulation platforms. This paper provides a systematic method to assess discrepancies between simulation tools. Models of the VSC and its control systems are implemented from scratch in two different tools. A metric and a methodology to quantitatively assess the discrepancies between simulation results is proposed and illustrated. The paper shows that even with a pedantic re-implementation of the models from the ground up, simulation results are still inconsistent. The objective of this paper is to develop a quantification method for comparing the models developed in different EMT simulation tool and to emphasize differences that can arise with the numerical solvers in such tools.QC 20150319</p

Analysis of Generator Forced Oscillations During MOD 25 Testing Exploiting Wavelets

This paper presents a measurement-based analysis of a 1.5 Hz forced oscillation triggered during a reactive power capability test conducted at a power plant in Dominion Energy’s power system. Owing to the slow evolving nature of the critical mode, it is demonstrated how time-frequency analysis of the period leading to the oscillation holds crucial information for finding the oscillation’s source. Furthermore, it is shown how the use of wavelets enables to more granular analysis of the evolution and impact of the forced oscillation – a capability that will help Dominion better monitor and regulate the dynamic components of an evolving grid