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This paper presents a modified droop-based control for dc voltage restoration in a Multi-Terminal dc (MTdc) system of parallel-operated buck converters. The proposed control structure is introduced to a proportional-derivative (PD) droop controller, which realises the active power — dc voltage droop control method. The additional control structure consists of an adaptive integrator, which decreases...
Real-time data redundancy is the main determinant of the state estimation (SE) performance, assessed considering the quantity, type, and location of measurements. Redundancy is a generic term used to given a rough idea of the strengths and weaknesses of measurement sets for SE. Data validation routines have a propensity to fail, when spurious measurements take place and inadequate redundancy levels...
A control system model of a virtual power plant with reactive power supply is proposed for small signal stability analysis of voltage control in medium voltage distribution grids. The model is linearized at different operating points and the damping factor is assessed. Depending on the virtual power plant's control parameters, oscillating system reactions can be observed. A parameter variation is...
This paper introduces a new model for Pumped Thermal Electricity Storage (PTES) devices as an emerging thermal storage technology. PTES devices are capable of reaching higher capacities than battery storage devices and therefore are suitable for grid-scale storage at the distribution voltage levels. The new model captures the inherent thermal characteristics, such as the variable efficiency, of the...
Typical microgrid configurations include small-scale generation units that belong to the class of reciprocating engines (gas, diesel, heavy fuel oil). A simplified equivalent model for representing the frequency response of a given set of this kind of generators is proposed in this paper. The model parameters are tuned to obtain frequency responses compliant with the performance classes stated by...
It has become a common practice of the manufacturers to provide only black-boxed models of devices to their buyers. These black-boxed models are compatible with time domain simulations. In this paper, a black-boxed EMT simulation model of a synchronous generator was connected to a known multi-machine power system, and an improved Prony Analysis method was used to identify the modes of the system from...
The extensive installation of gas-fired power plants in many parts of the world has led electric systems to depend heavily on reliable gas supplies. The use of gas-fired generators for peak load and reserve provision causes high intra-day variability in withdrawals from high pressure gas transmission systems. Such variability can lead to gas price fluctuations and supply disruptions that affect electric...
The development of renewable and intermittent power generation creates incentives for the development of both energy storage solutions and more flexible power generation assets. Pumped-storage hydropower (PSH) is the most established and mature energy storage technology, but recent developments in power electronics have created a renewed interest by providing PSH units with a variable-speed feature,...
With the rise of smart grids in distribution level, the new service of automatic network reconfiguration is established. Consequently, the power system topology may experience multiple changes during any day of operation. However, many services and applications require for reliable operation knowledge about the actual topology state which is provided by network control center. Even in case of communication...
This paper presents a statistical approach for identifying the significant impact of cracks on the output power performance of photovoltaic (PV) modules. Since there are a few statistical analysis of data for investigating the impact of cracks in PV modules in real-time long-term data measurements. Therefore, this paper will demonstrate a statistical approach which uses two statistical techniques:...
This paper describes an enhanced model for the Short Term Hydro Scheduling Problem, HSP, that includes the impact of operation decisions on the market prices and the possibility of adjusting the tailwater level and the generation and pumping efficiencies as a function of the flow. The solution approach uses an iterative procedure that solves in each iteration a linearized HSP problem using the linprog...
This paper describes the initial open-loop operation of a prototype control system aimed at mitigating inter-area oscillations through active DC power modulation. The control system uses real-time synchrophasor feedback to construct a commanded power signal added to the scheduled power on the Pacific DC Intertie (PDCI) within the western North American power system (wNAPS). The control strategy is...
Short term load forecasting (STLF) is an important part of generation scheduling and optimal energy management. Small island power systems, however, often have consumers that individually represent a relatively large percentage of the systems overall load and need to specifically forecast these individual loads. This paper, using data from two large industries in Trinidad and Tobago, evaluates the...
An Intentional Controlled Islanding (ICI) algorithm based on an exact Mixed Integer Programming Formulation (MILP) was previously proposed and tested using IEEE test systems. The proposed algorithm directly determines an islanding solution with minimal power-flow disruption for any given number of islands, while ensuring that each island contains only coherent generators. However, since one or more...
Inaccurate line loss predictions leads to additional regulation costs for Transmission System Operators (TSOs) that place energy bids at the day-ahead market to account for these losses. This paper presents a line loss prediction model design, applicable with the TSOs forecast conditions, that can reduce additional expenditure due to inaccurate predictions. The model predicts line losses for the next...
Over the last decade the use of battery energy storage systems (BESS) on different applications, such as smart grid and electric vehicles, has been increasing rapidly. Therefore, the development of an electrical model of a battery, capable to estimate the states and the parameters of a battery during lifetime is of critical importance. To increase the lifetime, safety and energy usage, appropriate...
The electric utility depends on accurate load predictions for scheduling spinning reserve, unit commitment, fuel allocation and maintenance. Artificial neural networks (ANNs) have been the popular method for load forecasting but support vector machines (SVM) have recently been successfully applied to the challenge of load forecasting. In this study, the ANN and SVM techniques were applied to short...
The mean variance mapping optimization technique (MVMO) is employed in this paper to solve the economic dispatch problem (ED) in power systems. The effectiveness of the proposed technique has been verified on three different case studies to solve the ED problem of thermal power units taking into account the transmission losses and other constraints which include generation limits, ramp rate limits,...
This paper presents a frequency control mechanism for an AC system through the active and reactive power loops of a VSC-HVDC system. The proposed scheme makes use of the reactive power loop for inertia support by exploiting the voltage-power sensitivity of loads, and active power droop control has been used to provide governor-like support following the large-disturbance. The performance of the presented...
This paper introduces a three-dimensional weighted Complex Network Theory (CNT) model to study the dependency and interdependency of cyber-physical systems (CPS) and to identify the most critical and vulnerable components within the coupled network. Based on CNT, the electric power buses within power system and communication routers and multiplexers within communication network are modelled as nodes,...
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