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In the future, mixed AC and DC grids, spanning multiple areas operated by different transmission system operators (TSO), are expected to offer the necessary controllability for integrating large amounts of intermittent renewable generation. This is facilitated by high voltage direct current transmission based on voltage source converter technology that can offer recourse actions in the form of preventive...
In this paper an Intentional Controlled Islanding (ICI) scheme is investigated as a last resort corrective action, to prevent an imminent blackout. The proposed methodology for ICI is based on simulated real-time measurements from Phasor Measurement Units (PMUs) which are used for online identification of power system dynamic behavior. The methodology aims to split the system into two islands based...
This work presents the development and evaluation of a new scheme based on Artificial Neural Network (ANN) for fault detection and fault location in distribution systems with distributed generator. Two different ANNs are used, where the first one is able to detect which part of the distribution system the fault occurred and the second one is able to precisely locate the fault along the faulty line...
Prognostic health management is an effective approach to enhance the reliability and reduce downtime of rotating machines, such as wind turbines. To achieve effective health management, fault prognosis is indispensable. This paper proposes a fault prognostic method for drivetrain gearboxes, which are one of the most troublesome subassemblies in wind turbines. The proposed method consists of signal...
This paper focuses on the evaluation of postgraduates' innovation ability based on cloud model. Considering that the innovation capability is mostly qualitative index and has strong fuzziness, the cloud model method can realize the effective conversion between the qualitative index and the quantitative value. Compared with traditional methods, the evaluation method is more scientific and the result...
With blossoming of wind power generation in the grid, many system operators recognize the requirement for additional flexibility to accommodate the variability and uncertainty from wind generation. Because of the high penetration of wind power, power systems are facing great operational challenges in maintaining generation balance. This study reviews the system flexibility requirement in a high wind...
Structural Analysis is a lucrative option for Fault Detection and Identification in Unmanned Aerial Vehicles (UAVs), because it handles detailed, large-scale mathematical models. It can be employed by an on-board flight computer to generate residual generators and implement automatic fault-detection. Contemporary algorithms applied on dynamic systems may yield residual generators which require the...
Traditional deterministic robust fault detection threshold designs, such as the norm-based or limit-checking method, are plagued by high conservativeness, which leads to poor fault detection performance. On one side they are ill-suited at tightly bounding the healthy residuals of uncertain nonlinear systems, as such residuals can take values in arbitrarily shaped, possibly non-convex regions. On the...
Mojette Transform (MT) based erasure correction coding possesses extremely efficient encoding/decoding algorithms and demonstrate promising burst erasure recovery performance. MT codes are based on discrete geometry and provide redundancy through creating projections. Projections are made of smaller data structures called bins and are generated from a two dimensional convex-shaped data. For exact...
A standalone microgrid with renewable and regular power resources along with storage system play an important role in remote areas in order to solve power supply problems. In this research, an optimal energy management of a standalone microgrid under different operational modes is studied. The objective of the optimization model is to improve energy utilization efficiency; reduce fuel cost and gas...
This paper presents a framework to determine the optimal siting and sizing of Wind-based distributed generators (WDGs) and energy storage systems (ESSs) in a micro-grid (MG), considering the total active power losses in the system, the self-adequacy index (SAI), and the total annual cost (TAC) of the WDGs and the ESSs. The work in this paper employs multi-objective optimization (MOO) based on archived...
This paper puts forwards a series of indexes to represent utilization rate and risk level of power system as well as to discuss their interrelationship. In particular, probabilistic risk assessment method is adopted in this paper to calculate security coefficient of over-limit voltage. Data envelopment analysis (DEA) is used innovatively to probe into the best balance point of system. By respectively...
Owing to the unprecedented challenges Distribution Network Operators (DNOs) are facing and driven by advances in information and communications technologies, Integrated Distribution Management Systems (IDMS) have been proposed and developed for more improved operation of distribution systems. Voltage and VAr control and Optimization becomes more and more critical in systems with increased operational...
In a hydro-dominated power system, with complex inter-temporal linkages, capacities of individual projects and project configurations are more complicated than using the simple megawattage, often used to denote capacity in thermally dominated systems. In this paper, the long term hydro scheduling problem is solved and used to test novel definitions of hydro-capacities, based on expected cost and cost...
This paper investigates the impact of demand response (DR) management on improving the social welfare of remote communities by integrating renewable energy (RE) resources into their diesel generator-based isolated microgrids. A multiple-year planning optimization problem is developed to determine the optimal combination of RE resources and energy storage system (ESS) while considering demand response...
There is an increasing demand to explore similar entities in big graphs. For example, in domains like biomedical science, identifying similar entities may contribute to developing new drugs or discovering new diseases. In this paper, we demonstrate a graph exploration system, called GQFast, which provides a graphical interface to help users efficiently explore similar entities. Methodologically, GQFast...
Modern software systems are becoming increasingly complex, relying on a lot of third-party library support. Library behaviors are hence an integral part of software behaviors. Analyzing them is as important as analyzing the software itself. However, analyzing libraries is highly challenging due to the lack of source code, implementation in different languages, and complex optimizations. We observe...
WAMS(Wide-area Measurement System) is one of the most potentially effective techniques to damp inter-area low frequency oscillations in power systems. This paper studies the data corruption phenomenon which is ubiquitous in WAMS and establishes the unified model of time-delay and data-loss. Then DTA(Damping Torque Analysis) index considering time-delay and data-loss is deduced based on the previous...
This paper studies the market interactions between MicroGrids (MGs) and Aggregators (AGs) from a noncooperative perspective. Specifically, we study a Generalized Nash Equilibrium Problem (GNEP), where players are the MGs and AGs, and aim at maximizing their respective benefits. MGs' actions are the generated energy as well as the traded energy with other MGs, whereas AGs actions are the load scheduling...
Modeling a location-unaware sensor network as a simplicial complex, where simplices correspond to cliques in the communication graph, has proven useful for solving a number of coverage problems under certain conditions using algebraic topology. Several approaches to finding a sparse cover for a fenced sensor network are considered, including calculating homology changes locally, strong collapsing,...
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