Component Modeling and Three-Phase Power-Flow Analysis for Active Distribution Systems
Author | : Mohamed Zakaria Kamh |
Publisher | : |
Total Pages | : 372 |
Release | : 2011 |
ISBN-10 | : 0494782498 |
ISBN-13 | : 9780494782491 |
Rating | : 4/5 (98 Downloads) |
Download or read book Component Modeling and Three-Phase Power-Flow Analysis for Active Distribution Systems written by Mohamed Zakaria Kamh and published by . This book was released on 2011 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a novel, fast, and accurate 3ϕ steady-state power-flow analysis (PFA) tool for the real-time operation of the active distribution systems, also known as the active distribution networks (ADN), in the grid-tied and islanded operating modes. Three-phase power-flow models of loads, transformers, and multi-phase power lines and laterals are provided. This thesis also presents novel steady-state, fundamental-frequency, power-flow models of voltage-sourced converter (VSC)-based distributed energy resource (DER) units. The proposed models address a wide array of DER units, i.e., (i) variable-speed wind-driven doubly-fed asynchronous generator-based and (ii) single/three-phase VSC-coupled DER units. In addition, a computationally-efficient technique is proposed and implemented to impose the operating constraints of the VSC and the host DER unit within the context of the developed PFA tool. Novel closed forms for updating the corresponding VSC power and voltage reference set-points are proposed to guarantee that the power-flow solution fully complies with the VSC constraints. All the proposed DER models represent (i) the salient VSC control strategies and objectives under balanced and unbalanced power-flow scenarios and (ii) all the operating limits and constraints of the VSC and its host DER unit.The new PFA tool, including the proposed DER and DSB models, is tested using several benchmark networks of different sizes, topologies, and parameters. Many case studies, encompassing a wide spectrum of DER control specifications and operating modes, are conducted to demonstrate (i) the numerical accuracy of the proposed models of the DER units and their operating constraints, (ii) the effectiveness of the proposed DSB model for the islanded ADN PFA, and (iii) the computational efficiency of the integrated PFA software tool irrespective of the network topology and parameters.Also, the slack bus concept is revisited, associated with the PFA, where a 3ϕ distributed slack bus (DSB) model is proposed for the PFA and operation of islanded ADNs. Distributing the real and reactive slack power among several DER units is essential to provide a realistic power-flow approach for ADNs in the absence of the utility bus. The proposed DSB model is integrated with the developed 3ϕ PFA tool to form a complete ADN PFA package.