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Although the installed wind generation capacity has grown remarkably over the past decades, percentage of wind energy in electricity supply portfolio is still relatively low. Due to the technical limitations of power system operations, considerable wind generation cannot integrate into the grid but gets curtailed. Among various factors, transmission congestion accounts for a significant portion of...
Independent system operators (ISOs) of electricity markets solve the security-constrained unit commitment (SCUC) problem to plan a secure and economic generation schedule. However, as the size of power systems increases, the current centralized SCUC algorithm could face critical challenges ranging from modeling accuracy to calculation complexity. This paper presents a distributed SCUC (D-SCUC) algorithm...
Recently, there has been a growing need to consider issues related to multiple uses of water—such as navigation, fishing, or recreation—in the operation planning of electrical power systems, specially in predominantly hydro systems. In short-term models, it is of particular importance to consider maximum/minimum values and ramp limits for the stream level of a river. However, in order to properly...
In restructured power systems, the transmission and distribution grids are autonomously utilized by independent system operator (ISO) and distribution companies (DISCOs), respectively. As the operating condition of one grid influences the decisions made by operators of other grids, the ISO and DISCOs should collaborate and cooperate with each other in order to operate the entire power system in a...
For a successful rollout of electric vehicles (EVs), it is required to establish an adequate charging infrastructure. The adequate access to such infrastructure would help to mitigate concerns associated with limited EV range and long charging times. Battery swapping stations are poised as effective means of eliminating the long waiting times associated with charging the EV batteries. These stations...
The day-ahead unit-commitment (UC)-based market-clearing (MC) is widely acknowledged to be the most economically efficient mechanism for scheduling resources in power systems.
Synchrophasor measurements, as obtained from phasor measurement units (PMUs), of power system frequency, voltages, and currents provide several important capabilities beyond the traditional 4-second substation data used in the energy management systems of control centers. These properties include precise time tagging of the measured data using GPS signals, high sampling rate at 30/50/60 samples per...
The paper investigates the applicability of averaged-value models (AVM) for modular multilevel converters (MMC) operating in a voltage sourced converter based high voltage dc (VSC-HVDC) grid. The AVM models are benchmarked by comparison with a detailed electromagnetic transient (EMT) model of the grid including a full-detail MMC model. Analysis results show that the AVM is only effective as long as...
This paper proposes a new model reduction algorithm for power systems based on an extension of balanced truncation. The algorithm is applicable to power systems which are divided into a study area which requires a high-fidelity model and an external area, making up most of the power system, which is to be reduced. The division of the power system can be made arbitrarily and does not rely on the identification...
This paper presents a quantitative method to determine delay requirements of the information and communication technology (ICT) system supporting wide-area power oscillation damping (WAPOD) controllers. An allowable time delay for the ICT infrastructure named “equivalent time delay (ETD)” is defined. The ETD is calculated by numerically comparing the damping behavior of the system when local input...
A novel model predictive control (MPC) scheme is developed for mitigating the effects of severe line-overload disturbances in electrical power systems. A piece-wise linear convex approximation of line losses is employed to model the effect of transmission line power flow on conductor temperatures. Control is achieved through a receding-horizon model predictive control (MPC) strategy which alleviates...
This paper presents a mixed-integer linear programming (MILP) reformulation of the thermal unit commitment (UC) problem. The proposed formulation is simultaneously tight and compact. The tighter characteristic reduces the search space and the more compact characteristic increases the searching speed with which solvers explore that reduced space. Therefore, as a natural consequence, the proposed formulation...
Usage of wide area PSSs (WAPSS) in actual power systems is limited because of their restricted adaptability to different operating conditions. Numerous adaptive control methods have been proposed to solve this problem, but they are limited due to strict prerequisites, such as the necessity of consistent excitations or large disturbances. This paper, therefore, presents a novel adaptive wide area PSS...
The presence of high levels of Renewable Energy Resources (RES) and especially wind power production poses technical and economic challenges to System Operators, which under this fact have to procure more Ancillary Services (AS) through various balancing mechanisms, in order to maintain the generation-consumption balance and to guarantee the security of the grid. Traditionally, these critical services...
Power systems around the world have set ambitious targets for renewable energy integration. Several jurisdictions incentivize renewables such as the Feed-in Tariff in Ontario, Canada. These incentives shall eventually run out and renewables would have to competitively sell energy into electricity markets, overcoming uncertainty and variability in their output. This paper proposes a Wind Generators...
This paper presents a novel approach for the transmission network expansion planning under generalized joint generation and transmission n-K security criteria. The proposed methodology identifies the optimal expansion plan while modeling the power system operation under both normal and contingency states. An adjustable robust optimization approach is presented to circumvent the tractability issues...
This paper describes the development of a modern power system laboratory within a Bologna Declaration compliant curriculum at the Department of Energy and Power Systems, Faculty of Electrical Engineering and Computing, University of Zagreb. The paper describes laboratory components and provides insight into the experiments that students are required to perform. The laboratory course is divided into...
Power system operation practices are changing with the addition of renewable energy resources such as photovoltaic (PV) sources. The diverse and intermittent nature of these resources demands new operation strategies to ensure system reliability. As more PV units are added to power systems, the power generated by conventional generation resources should be reduced to accommodate these new resources...
Aluminum production relies on the smelting process which consumes huge electrical energy. One possible solution to reduce the fossil fuel consumption by aluminum production is the integration of wind power. Based on this background, this paper studies an isolated power system for aluminum smelting production with a high penetration of wind power. A dynamic model of the aluminum smelter load (ASL)...
Communication network brings new challenges such as time delay and data loss to wide-area damping control of power systems. The uncertainty caused by stochastic time delay of network communication increases the difficulty of wide-area control performance analysis. This paper proposes a mathematical expectation modeling approach to model and analyze wide-area controlled power systems considering the...
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