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This paper discusses the design and usage of a SIMULINK-based Phasor Measurement Unit (PMU) simulator package.1 The motivation for developing the package is to provide a flexible environment for teaching phasor measurement and frequency estimation to advanced undergraduate and graduate students, and providing a knowledge base to students for research. This software allows for the exploration of the...
This presentation is motivated by the recent increase in the number of phasor measurement units (PMU) installed in substations which suggests that it is not unrealistic to assume that most transmission systems will soon be fully observable by only PMU measurements. When there are sufficient number of PMU measurements to make the system observable, then state estimation problem can be formulated in...
The fault ride-through capability (FRTC) of a full rated converter wind turbine relies on the operation and control of the grid-side converter. To enhance the FRTC of the wind power generation system (WPGS), this paper investigates a novel controller for the grid-side converter, based on nonlinear adaptive control (NAC). Lumped perturbation terms are defined in the NAC to include all unknown and time-varying...
This paper presents control algorithms and sizing strategies for using energy storage to manage energy imbalance for variable generation resources. The control objective is to minimize the hourly generation imbalance between the actual and the scheduled generation of wind farms. Three control algorithms are compared: 1) tracking minute-by-minute power imbalance; 2) postcompensation; and 3) precompensation...
This paper proposes a chronological probability model of photovoltaic (PV) generation on the basis of conditional probability and nonparametric kernel density estimation. In addition to randomness of PV power, the correlation of PV powers between adjacent time points and the uncertainty of start and end moments of PV output can be represented. The proposed model can be employed to produce random PV...
This paper presents a new approach to voltage estimation for N−1 contingency analysis. The voltage magnitude after a single line or generator outage is estimated using a voltage sensitivity matrix. The sensitivity matrix is derived using phasor measurements during normal operation. This technique is compared to the traditional voltage sensitivity calculation using the Jacobian of the system, which...
Daily trip distance and end time of the last trip are two essential variables for home based electric vehicle (HBEV) charging load model. A non-parametric Gaussian kernel density estimation method is proposed to build the probability density distributions of these two variables. This method can improve the precision and adaptability of the distributions compared with parametric estimation. A Latin...
Demand response aims at utilizing flexible loads to operate power systems in an economically efficient way. A fundamental question in demand response is how to conduct a baseline estimation to deal with increasing uncertainties in power systems. Unfortunately, traditional baseline estimation lacks the ability to characterize uncertainties due to their deterministic modeling. This deficiency often...
Charging control strategies can significantly alleviate the impact of electric vehicles (EVs) to power systems, as well as utilize the flexibility of EV charging to achieve extra benefits. This paper proposes an EV charging control strategy to achieve valley-filling using EV charging load. The strategy consists of system-level control and supporting control for the charging of individual EVs. The...
Scheduling of storage devices in microgrids with multiple renewable energy resources is crucial for their optimal and reliable operation. With proper scheduling, the storage devices can capture the energy when the renewable generation is high and utility energy price is low, and release it when the demand is high or utility energy price is expensive. This scheduling is a multi-step optimization problem...
Nowadays, power companies are actively promoting the construction of power quality monitoring system (PQMS). There is a vital need to deal with the large amount of data extracted from PQMS. This paper proposes a novel method of fault location estimation based on the voltage sag records of PQMS. By this method, fault position and fault resistance can be estimated by particle swarm optimization algorithm...
This work presents a comparative study of Least Squares Filter, Kalman Filter and Unscented Kalman Filter for estimating the secondary current phasor distorted due to saturation of Current Transformers (CTs). Several distorted current signals were generated in a Real Time Digital Simulator (RTDS) and embedded in noise. Then, these signals were segmented in two kinds of regions, named saturated and...
Conservation voltage reduction (CVR) is a technique for lowering energy consumption by reducing customer voltages while remaining within specified service voltage ranges. It is widely used by utilities and advocated by some regulatory bodies. However, in order to lower customer voltages while keeping them within standard ranges, it is important to know where the voltage starts. Available models of...
In this paper estimation of three-phase transmission line parameters is done with the help of synchrophasor measurements by using a recursive regression technique based on the Kalman filter. The errors in the regression vector due to presence of noise in the synchrophasor data are also accounted for while estimating the parameters. The performance of this technique is demonstrated for a medium length...
Solving economic dispatch problem (EDP) in a distributed way has attracted lots of attention in recent years due to its scalability and robustness to single points of failure. Robust distributed system Incremental Cost Estimation (RICE) algorithm has been proposed to solve the classic EDP in a distributed way considering communications information losses. However, assuring the stability of the algorithm...
To accommodate the fast power fluctuations associated with PV generation, a hybrid energy storage system (HESS) consisting of a battery energy storage system (BESS) and super-capacitor is evaluated in this paper. A probabilistic approach for determining the power capacity specification for the HESS is proposed. This method would allow the capacities of the BESS and super-capacitor to be properly designed...
Multiple distributed harmonic sources, such as inverter-interfaced distributed generation (DG), in distribution systems have posed new challenges in identifying the cause of harmonic voltages or currents observed at a specific location. This paper proposes a new method to estimate harmonic contribution using nonlinear optimization techniques. First, definitions are provided and the problems are described...
In this paper, least square estimation (LSE)-based dynamic generator model parameter identification is investigated. Electromechanical dynamics related parameters such as inertia constant and primary frequency control droop for a synchronous generator are estimated using Phasor Measurement Unit (PMU) data obtained at the generator terminal bus. The key idea of applying LSE for dynamic parameter estimation...
This paper poses the problem of modeling price responsive demand as one of identifying the transfer function between the price and power consumption. This is motivated by the team's earlier work of econometric estimation of the self- and cross-elasticity of demand response. It is discovered that electricity consumption has several unique features that may render the traditional approach ineffective...
The inertia of the power system is reduced in the presence of Renewable Energy Sources (RESs) due to their low or even no contribution in the inertial response as it is inherently available in the Synchronous Machines (SMs). The total inertia of the grid becomes unknown or at least uncertain following outage of SMs during cascading events. Therefore, the active power deficit following the disturbance/s...
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