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This paper presents the study results on integration of VSC HVDC and variable speed hydropower generation. Different types of variable speed hydropower generation solutions have been reviewed. Refined calculation on annually additional power generated and reliability assessment have been illustrated for the proposed solution based on real hydropower plant parameters. Advantages and challenges for...
Achieving supply demand balance in power systems requires controllable energy storage. The primary sources of controllable storage are the fuel stockpiles at generators (i.e. gas, coal, water, etc.). There is increasing interest in alternative forms of storage due to factors such as the continuing increase in intermittent energy generation sources, concerns with increasing network costs and demand...
In large storage systems, erasure codes is a primary technique to provide high reliability with low monetary cost. Among various erasure codes, a major category called XORbased codes uses purely XOR operations to generate redundant data and offer low computational complexity. These codes are conventionally implemented via matrix based method or several specialized non-matrix based methods. However,...
Many applications today rely on multiple services, whose results are combined to form the application's response. In such contexts, the most unreliable service and the slowest service determine the application's reliability and response time, respectively. State-machine replication and atomic broadcast are fundamental abstractions to build highly available services. In this paper, we consider the...
We introduce a low-latency stochastic decoding algorithm, called conditional stochastic decoding, to implement iterative Low-Density Parity-Check (LDPC) decoders. The conditional stochastic decoder, which utilizes reliable messages in the decoding process and the channel receiving probability to generate stochastic streams, improves error rate performance and decreases decoding latency. Compared to...
The failure of floating wind turbine can suspend the operation of the offshore wind turbine generator, which will severely affect the generated energy and cause huge economic loss. Hence, the reliability evaluation of floating wind turbine is of vital importance. RPN calculation which adopts the traditional FMEA method carries significant limitations and cannot solve failure sequence in case RPN is...
Wind turbine generators are subjected to unusual environments and stresses. In this paper we will discuss several types of wind generator insulation failure mechanisms as well as forensic analysis results of several different manufacturers' systems. The types of generators studied include induction, wound rotor, and permanent magnet across a number of output voltages and environmental conditions....
This paper1 examines five strategies for upset protection in Gold sequence generators used to maintain signal acquisition in GPS receivers. This work is motivated by the increased prevalence of single-event upsets in ultra low-power GPS receivers. If any upset occurs in the Linear Feedback Shift Register (LFSR) modules, then the corresponding satellite signal must be re-acquired, resulting in high...
The integration of increasing amounts of intermittent renewable generation whose reliability contributions are significantly different than those of the historically dispatchable thermal generating units is important to future electric generation planning. With relatively small amounts of intermittent generation, reliability impacts may not be detectable; however, as renewable integration goals continue...
This paper describes enhancements to ATC's cascading study criteria and the implementation of a fast automated process using POM/OPM software for conducting comprehensive steady state multiple element contingency screening and cascading analysis, finding mitigations to restore the system to be within emergency and/or normal performance limits, and automatically tabulating significant results and summaries...
In this paper we propose to schedule both real power and voltage settings of generators participating in electricity markets. This can be done by utilizing an extended AC Optimal Power Flow (AC X-OPF). This will provide a one-step method performed by the Independent System Operator (ISO) in charge of electricity market clearing; iterative decisions by the ISO and the system operator ultimately responsible...
This paper presents a methodology for developing an adequacy assessment of the generating and storing mix capacity in nearly-Zero Energy Residential Buildings (nZEB). The adequacy of a given generating and storing mix will be quantified by means of a set of reliability indices obtained by adapting the traditional reliability techniques employed in power systems. The analysis will use a Montecarlo...
Under high penetration of wind and solar, the power system is facing the challenge to maintain the balance between generation and load due to the insufficient ramping capability. To resolve this challenge, a new market mechanism was proposed by many ISOs to add the flexible ramping constraints or flexible ramping product to maintain the ramping flexibility in addressing net load uncertainty and variability...
The purpose of this paper is to describe the method used to calculate the Reliability and Availability estimations of the Uninterruptible Power Supply (UPS) systems using Monte-Carlo simulation method. In this method, the failure rates (λ), and availability (A) of the major components in the UPS are simulated by the use of random number generators. The main objective of this method is to produce,...
A probability distribution model of tidal generation power is needed to perform reliability assessment and other probabilistic analyses of a power system with tidal sources. This paper proposes a Wakeby distribution to model the probabilistic characteristic of tidal current speed. Wakeby and other four popular distributions are investigated using four years of tidal current data at five sites. The...
The paper highlights the reliability estimation tool for power system's reliability estimation study. The reliability estimation tool was applied to the different configurations of Uninterruptible Power Supply (UPS) systems Capacity, Isolated Redundant, Parallel Redundant, Distributed Redundant, and System plus System Redundant configurations. UPS reliability parameters such as failure rates, Mean...
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...
Reliability of the electricity grid against insufficient natural gas supply is becoming an increasingly relevant topic as the number of natural gas-fired generation units continues to grow. Without sufficient natural gas quantities at the market the loss of multiple generating units may occur with high probability. Existing power system operation practices are not designed to cope with the wide-spread...
The effects of the polar vortex in the United States were initially felt in the Midwest, but these low temperatures quickly spread to nearly all portions of the Eastern and Texas Interconnections. Temperatures were far colder than those normally experienced in winter, resulting in record winter peak electric demands with increased electric heating requirements. This is the first time that data from...
Electricity markets contain many uncertainties such as changes in generation and demand levels. Especially with increasing integration of wind power, uncertainties in generation availability have increased. This increases the network access risk for generators. Therefore, the need for a reliability mechanism for generators has emerged. Firm transmission access is a transmission reliability mechanism...
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