The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper presents a new approach in estimating important parameters of power system transient stability model such as inertia constant and direct axis transient reactance in real time. It uses a variation of unscented Kalman filter (UKF) on the phasor measurement unit (PMU) data. The accurate estimation of these parameters is very important for assessing the stability and tuning...
Accurate information about dynamic states is important for efficient control and operation of a power system. This paper compares the performance of four Bayesian-based filtering approaches in estimating dynamic states of a synchronous machine using PMU data. The four methods are Extended Kalman Filter, Unscented Kalman Filter, Ensemble Kalman Filter, and Particle Filter. The statistical performance...
Demand response (DR) has proved to be an inevitable part of the future grid. Much research works have been reported in the literature on the benefits and implementation of DR. However, little works have been reported on the impacts of DR on dynamic performance of power systems, specifically on the load frequency control (LFC) problem. This paper makes an attempt to fill this gap by introducing a DR...
This paper deals with the selection of feedback signal(s) that retain the modal behavior of power system electromechanical dynamics under varying operating circumstances. The approach seeks signals that have relatively large magnitude of residue, less variation of the magnitude and phase angle, sufficient gap between the critical pole-zeros, and least sensitive to other modes. The methodology is tested...
A suitable networked control scheme and its stability analysis framework have been developed for controlling inherent electromechanical oscillatory dynamics observed in power systems. It is assumed that the feedback signals are obtained at locations away from the controller/actuator and transmitted over a communication network with the help of phasor measurement units (PMUs). Within the generic framework...
The integration of intermittent generation in power grids, such as wind energy, imposes new challenges for transmission congestion management. In order to solve this problem, energy storage systems (ESS) have been proposed in the literature, as they provide an efficient mechanism for balancing variability while reducing operational costs. This paper presents a comprehensive analysis of the dynamic...
Phasor measurement units (PMUs) provide the basis for synchrophasor measurements, which are good data sources for capturing power system dynamic behavior. The recently published IEEE Standard C37.118.1-2011 characterizes the dynamic performance of synchrophasor measurements with two performance class filters: P-class and M-class. Practical implementation of a PMU to meet all dynamic requirements is...
This paper concerns a novel approach to the modeling and control design for transient stabilization of electric power systems using Flexible Alternating Current Transmission System (FACTS) devices. A nonlinear dynamic model of general interconnected electric power systems in the Ordinary Differential Equation (ODE) form is proposed in terms of time-varying phasors of all dynamic components. This model...
This paper presents a novel approach to enable frequent computational cycles in online dynamic security assessment by using the terms of the transient energy function (TEF) as input features to a machine learning algorithm. The aim is to train a single classifier that is capable of classifying stable and unstable operating points independent of the contingency. The network is trained based on the...
In this paper, we present a mixed-integer formulation with nonlinear production functions of the day-ahead hydro unit commitment problem for hydro-dominant power systems. The objective is to minimize unit startup and shutdown costs and maximize water use efficiency in the daily operation of multiple hydro plants. Determination of hourly generation dispatches and unit configurations is subject to reservoir...
In this paper, the empirical observability Gramian calculated around the operating region of a power system is used to quantify the degree of observability of the system states under specific phasor measurement unit (PMU) placement. An optimal PMU placement method for power system dynamic state estimation is further formulated as an optimization problem which maximizes the determinant of the empirical...
Modeling and simulation of power systems for general-purpose transient studies has been receiving significant attention in the literature. Among recently proposed methods, the so-called shifted-frequency analysis (SFA) approach has been shown to facilitate accurate and numerically efficient simulation of electromagnetic and electromechanical transients with the use of dynamic phasors. This paper proposes...
Frequency control from the demand side presents a novel and viable way to complement control by traditional generators. This paper presents practical guidelines for system operators to select gain settings for a proposed frequency-based load control strategy. Simulation tests in a large interconnected system model demonstrate the robustness to different values of control gains, and sensitivities to...
There is a growing interest in utilizing demand-side flexibility to provide ancillary services. Various methods have been proposed for frequency control with thermostatically controlled loads, yet few consider practical load constraints. In this paper, we develop a fully decentralized method to provide primary frequency control (PFC) with domestic refrigerators taking into account startup compressor...
This paper presents a state estimator based on the use of a particle filter (PF). Unlike other types of filters, a PF is suitable for both nonlinear systems and non-Gaussian error distributions. The proliferation of distributed energy resources such as distributed generators and controllable loads has been accompanied by a high degree of uncertainty because the lack of sensors necessitates the use...
One of the factors hindering the large scale integration of wind power is the post contingency congestion of a network due to limited availability of network capacity and auxiliary constraints. Under such conditions, the network operators can potentially request a curtailment of wind farm output if the remedial strategies fail. The paper investigates this problem in detail and proposes a mathematical...
This paper describes an approach for determining generation-shedding for dynamic Remedial Action Scheme (RAS) based on minimum cost. A generation-shedding cost function is developed based on generator fuel cost, startup/shut down cost, and bid price. The proposed method updates RAS control actions online based on the system operating conditions and cost functions. The Single Machine Equivalent (SIME)...
Accurate estimation of dynamic states is important for monitoring and controlling transient stability. This paper proposes an adaptive interpolation approach to improve the performance of the Extended Kalman Filter (EKF) for estimating dynamic states of a synchronous machine. This approach consists of two major steps. First, the non-linearity of state transition function and measurement function is...
This paper describes the evolution of state estimators from the legacy static state estimators to the distributed dynamic state estimators. Dynamic state estimators are computational demanding and only distributed approaches are practical. We present two specific distributed dynamic state estimators: (a) the quasi-dynamic state estimator which uses GPS-synchronized and non-synchronized measurements...
This paper demonstrates the effectiveness of post-fault corrective control action through the planned Western HVDC link in the Great Britain (GB) transmission network. It is shown that both transient as well as oscillatory stability problems could be tackled using such a corrective control strategy which allows higher pre-fault loading of the AC network without compromising security. The corrective...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.