Chandan Kumar Chanda

The present-day power grid is basically a complex power transmission network with risks of failure due to unplanned attacks and contingencies, and therefore, assessment of vulnerability of transmission network is important and the process is based on contingency approach. This book deals with the methods of assessment of the grid network vulnerability and addresses the grid collapse problem due to cascaded failures of the transmission network following an attack or an unplanned contingency. Basic mitigation aspects for the network has been explored and the immunity of such a power transmission network against vulnerable collapse has been described using mathematical models.

Ziel der vorliegenden Arbeit ist es, einen neuen Spannungsstabilit tsindex in einer radialen Verteilungsstruktur unter Ber cksichtigung von verteilten Generatoren (DG) zu ermitteln. Um dies zu erreichen, wurden Analysen und Studien f r verschiedene Lasttypen mit und ohne Ber cksichtigung von DG durchgef hrt. Ein Indikator wird verwendet, um den richtigen Standort eines verteilten Generators zu bestimmen. F r die ideale Gr e von DG wird ein Algorithmus vorgeschlagen, der einige Einschr nkungen ber cksichtigt. Nach dem Testen und der Analyse dieser Technik in einem mittelgro en Verteilernetz wurde festgestellt, dass sich das System durch die Platzierung einer angemessenen Gr e des dezentralen Generators an einem optimalen Standort in Bezug auf das Spannungsniveau, die Verringerung der Verluste und die Stabilit t des Systems verbessert hat. Hier kann eine maximale Auslastung des bestehenden Systems erreicht werden, indem die Kunden mit minimaler Ausfallh ufigkeit und minimaler Ausfalldauer innerhalb der vorhandenen Ressourcen zufrieden gestellt werden.

Les objectifs du pr sent travail sont d' tablir un nouvel indice de stabilit de la tension dans une structure de distribution radiale en tenant compte des g n rateurs distribu s (DG). Pour ce faire, des travaux d'analyse et d' tude ont t men s pour diff rents types de charges avec et sans prise en compte des g n rateurs distribu s. Un indicateur est utilis pour identifier l'emplacement appropri du g n rateur distribu . Un algorithme est propos pour d terminer la taille id ale du g n rateur distribu en tenant compte de certaines contraintes. Apr s avoir test et analys cette technique sur un r seau de distribution de taille moyenne, il a t conclu que le placement d'un g n rateur de taille appropri e l'emplacement optimal a am lior le niveau de tension, la diminution des pertes et la stabilit du syst me. Ici, l'utilisation maximale du syst me existant peut tre r alis e en satisfaisant le client avec une fr quence de panne minimale et une dur e d'interruption minimale dans le cadre des ressources existantes.

L'obiettivo del presente lavoro stabilire un nuovo indice di stabilit della tensione in una struttura di distribuzione radiale considerando i generatori distribuiti (DG). A tal fine, sono stati condotti lavori di analisi e studio per vari tipi di carichi con e senza considerare i DG. Un indicatore viene utilizzato per identificare la posizione corretta del generatore distribuito. Per la dimensione ideale del DG viene proposto un algoritmo che tiene conto di alcuni vincoli. Dopo aver testato e analizzato questa tecnica su una rete di distribuzione di medie dimensioni, si concluso che il posizionamento di un DG di dimensioni adeguate in una posizione ottimale ha migliorato il sistema in termini di livello di tensione, riduzione delle perdite e stabilit del sistema. In questo modo, possibile ottenere il massimo utilizzo del sistema esistente, soddisfacendo il cliente con la minima frequenza di guasto e la minima durata di interruzione nell'ambito delle risorse esistenti.

Os objectivos do presente trabalho consistem em estabelecer um novo ndice de estabilidade de tens o na estrutura de distribui o radial, considerando os geradores distribu dos (DG). Para o seu cumprimento, foram realizados trabalhos de an lise e estudo para v rios tipos de cargas com e sem considerar a DG. Um indicador utilizado para identificar a localiza o adequada do gerador distribu do. Para a dimens o ideal da DG proposto um algoritmo considerando alguns constrangimentos. Ap s testar e analisar esta t cnica na rede de distribui o de tamanho m dio, conclui-se que a coloca o do tamanho adequado da DG no local ptimo, o sistema melhorou em termos de n vel de tens o, diminui o das perdas e estabilidade do sistema. Aqui, a m xima utiliza o do sistema existente pode ser alcan ada atrav s da satisfa o do cliente com uma frequ ncia m nima de falhas e uma dura o m nima de falhas dentro dos recursos existentes.

Objectives of the present work are to establish a new voltage stability index in radial distribution structure by considering distributed generators (DG). For fulfilment of this, analysis and study works were carried on for various types of loads with and without considering DG. One indicator is utilized to identify the proper location of distributed generator. For ideal size of DG an algorithm is proposed considering some constraints. After testing and analysis of this technique on medium size distribution network, it is concluded that placement of proper size of DG at optimal location the system has improved in terms of voltage level, decrease of losses and stability of the system. Here, maximum utilization of the existing system can be achieved by satisfying the customer with minimum frequency of failure and minimum duration of outage within the existing resources.