Angle Control-Based Multi-Terminal Out-of-Step Protection System

From time to time a sequence of unexpected and overlapping contingencies may lead to power system angular instability and even blackouts if not addressed adequately by means of an out-of-step (OOS) protection system. The motivation of the paper is an attempt to develop a workable prototype of the OOS protection system. The deficiencies of the protection currently used in the Latvian Power System network are highlighted and a new protection structure is proposed. The protection system comprises of several strategically located terminals, exchanging information in real time by means of a communication network. The OOS condition detection method is based on system-wide generation sources, electromotive forces, vectors, and angle control. The network splitting decision is based on generator coherence evaluation. Protection terminals determine online the groups of coherent generators and choose the splitting boundary from a predefined transmission lines (TLs) cut sets list. The protection system structure, algorithm of operation, and possible IEC 61850 communication standard-based implementation are described

The Influence of the Restrictions of the Electromagnetic Field on the Capital Costs of Power Line

The paper presents the minimization concept of the capital costs of the power line design by optimizing the main parameters of a transmission line as well as possibility of use of new advanced technologies such as High Temperature Low Sag conductors and monitoring systems. The evaluation process of a concept is presented in three stages and takes into account the impact of the important factors such as thermal, mechanical and environmental limitations. The main interest in this paper is focused on the detection of a problem of an electrical field, which may not satisfy to the required level, thus being as a problem in the transmission network “bottlenecks”. Moreover the proposed practical method hands an efficient solution of the presenting problem allowing the customer to choose the best alternative of a power line design. The obtained results are analyzed and discussed in a paper

Review of Advanced Transmission Technologies Towards the Smart Grid

The progressive re-engineering of the existing power networks requires the innovative transmission technologies, which will be able to adapt to new concepts of operation and management of Smart Grid. Moreover, the level of implementation of these technologies by Transmission System Operators (TSOs) will vary from one control area to the other, also based on past experiences and today’s operation constraints. This paper presents an overview of general groups of such technologies, namely, passive equipment, active equipment, real time system monitoring equipment as well as the impacting TSOs’ operations equipment with the main purpose to analyze the prospective opportunities of realization of examined technologies as well as for achieving the better assessment of advantages of Smart Grid. The advanced technology such as High Temperature Low Sag (HTLS) conductors was examined based on a real line design case.

Transmission and Optical Networks Creating by Using a Cooperative Game Theory Approach

This paper is dedicated to the task of planning energy supply systems in the market environment. The possibilities of forming coalitions between companies are considered. In this case, for justifying the decisions and distributing the gains, cooperative game theory is used. The example with the proposed strategy is based on a real project of 330 kV and 110kV high voltage lines and optical communication line between two substations and shows the rationality and efficiency of using the considered approach

Analysis and modeling challenges induced by a growing penetration of inverter-interfaced der

The anticipated growing penetration of inverter-interfaced DER affects several aspects of power system analysis ranging from the impact on the system behavior to the modeling and simulation needs of the new technologies. The adequate representation and assessment of the role of the self-commutated converters is addressed through a number of challenges illustrated by a set of examples dealing with system integration of DER, islanded operation of self-commutated converters and modeling and simulation requirements. A generic model of self-commutated converter is proposed allowing their representation in phasor-type simulation programs

Leveraging Pumped Storage Power Plants for Innovative Stability Enhancement of Weakly Interconnected Power Systems

The hybrid AC/DC grid, based on a significant share of renewable energy sources, is gradually becoming an essential aspect of the modern energy system. The integration of intermittent renewable generators into contemporary energy systems is accompanied by the decommissioning of power plants containing synchronous generators. Consequently, this leads to a reduction in system inertia and an increase in the risk of stability disruption. The abrupt disconnection of the primary generator or power line can result in an unanticipated mismatch between power generation and consumption. This discrepancy can trigger substantial and swiftly evolving alterations in power distribution, angular speed, load flow, and the frequency of generators. The risks of an energy system collapse can be mitigated through automation, enabling rapid adjustments to generation and load capacities, as well as power flows, in the electrical network. This article justifies the utilisation of a power control method for high-voltage power line interconnections. The technology of hydro storage power plants and measurements of voltage phasors are employed. The potential for easing power flow restrictions and realising substantial economic benefits is supported by the results obtained using simplified dynamic model of the Baltic power system and Nord Pool electricity market model

Review of Advanced Transmission Technologies Towards the Smart Grid

Review of Advanced Transmission Technologies Towards the Smart Gri

Research and Simulation of Overhead Power Line Uprating Using Advanced Conductors

Due to the deregulation of the electricity market around the world as well as the great impact of renewable energy sources and climate change patterns, uprating of existing overhead power lines (OHPL) has become more popular. There are several methods that are widely used to uprate power lines (PL), but most of them are expensive. However, the use of the advanced conductors such as High Temperature Low Sag conductors (HTLSCs) could provide various technical and economical advantages for an effective operation of the PL. This paper presents the comparison results of both the traditional type conductors and HTLS conductors based on the evaluation of the line thermal rating (LTR) under several sets of local ambient conditions. These computations have been conducted on the basis of IEEE and CIGRE ampacity standards by using PLS-CADD software

Energosistemu relejaizsardzibu un automatikas tikla elementu izstrade un ieviesana ekspluatacija

Available from Latvian Academic Library / LAL - Latvian Academic LibrarySIGLELVLatvi