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The paper focuses on reliability assessment of power systems with wind power generation. A Monte Carlo based production cost simulation model is introduced in the paper. The model closely simulates actual system operation processes and takes system random behaviors into account. A simplified unit commitment method is created to fit the simulation for reliability evaluation purpose. The effects of...
This paper introduces definitions and an analysis method for estimating how much kinetic energy can be made available for inertial response from a wind turbine over a year, and how much energy capture must be sacrificed to do so. The analysis is based on the static characteristics of wind turbines, Weibull distributions of wind speed, and standard definitions of turbulence intensity. A control scheme...
We show how to combine together voltage angle phasor measurements at several buses to measure the angle stress across an area of the power system that is called a cutset area. The angle across the cutset area is a weighted average of the angles measured at buses at the borders of the cutset area. The angle across the cutset area is based on circuit theory and it responds to power flow through the...
The control algorithms proposed in the literature so far for the Double Output Induction Machine Based Variable Speed Constant Frequency (VSCF) stand alone generators suffer from the disadvantage of loss of `field orientation' during sudden load disturbance at the machine terminal. As a result, undesirable transients are observed in the load voltage during such transients. This paper presents a new...
High penetration of wind power has posed great challenges to power system operators. Extensive research has been done aiming to improve the power system operations. Various mechanisms such as stochastic unit commitment and reserve calculation methods have been proposed. However, the power system operators may have different views on the research results due to practical constraints. This paper looks...
Wind generation is evolving from single wind turbines to wind power plants with an installed capacity of tens of megawatts. Therefore, wind turbines are also coupled to the transmission grid instead of the distribution grid. Problems arise during grid faults as the behaviour of wind turbines equipped with doubly-fed induction generators differs fundamentally from traditional synchronous generators...
This paper assesses the effects of the future European power generation system with strict CO2 emission reduction targets on the planning of cross-border interconnection lines. Results from a techno-economic energy systems model have been used as input to this work, regarding the development of the European power generation system until the year 2050, meeting the EU 2020 CO2 target and a 85% emissions...
This paper presents updated results from a Monte Carlo simulation method of operational needs created by variable generation renewables coupled with a Production Simulation methodology to assess whether the California ISO's existing generation fleet can provide the needed flexibility for ramping, load following and Regulation under a 20% Renewable Portfolio Standard. The production simulation methodology...
This work presents the basis of a new approach for fault diagnosis in Electrical Distribution Systems (EDS). This approach aims to classify different types of faults by means of the factor named as Negative Sequence Factor (F2). This factor is calculated from post-fault negative sequence and pre-fault positive sequence currents using Thévenin equivalents. Series, shunt and simultaneous faults with...
Electricity supply industry worldwide has been identified as a major source of greenhouse gas emissions. Consequently, many countries have started to implement emission trading schemes (ETS). Separate and evolving public policy debates are shaping Electricity Market, Carbon Market, and Renewable Market without attention to how each market affects the others, yet the markets have overlapping goals...
Micro smart grid technology provides a desirable infrastructure for energy efficient buildings. In additional to the power source from the grid, a micro grid for buildings may contain autonomous power generators possibly CHP, renewable energy resources such as PV solar cells, power storage devices and system loads including HVAC systems, lighting equipment, IT data centers, etc. With support of a...
Wide-area measurements have been proposed to coordinate generator excitations and Static Var Compensator (SVC) auxiliary controls. The wide-area coordinating controller (WACC) utilizes remote signals to compensate the interactions between SVC and generator variables, therefore it provides an additional damping of both local and inter-area oscillations. However time delays introduced by remote measurement...
While one of the strongest points in a power system is the substation, it still contains what can be described as weak points or points of failure that could lead to major outages. Present paper examines the impact of Superconducting Fault Current Limiter (SFCL) on the transmission substation reliability. To this end, potential application of a SFCL in a practical 138 kV transmission grid is studied...
Field study indicates that more than 90% lightning stroke trip-out accidents for UHV transmission lines are caused by lightning shielding failure flashover. The large scale of the tower and the high operation AC voltage increase the probability of direct lightning strokes attaching to the phase conductor of double circuit UHV transmission line. The unexpected high lightning shielding failure flashover...
Smart grid technologies in combination with the methodological foundation laid by the economic theory of Priority Service, enable the conversion of electric service reliability from a public good to a private good. Such a transformation is achieved by offering electricity service as a product line differentiated according to service reliability from which customers can self-select the level of reliability...
Increasing number of wind farms (WFs) connected to power systems calls for efficient aggregate models so that large farms can be represented by only few equivalent wind turbines for steady state and dynamic system studies. A wind power plant consists of many small generators inside a wind farm. Future wind projects predict even greater number of wind turbines inside a wind farm for increased capacity...
The present transmission system was not designed to work efficiently as a means of delivering large amounts of renewable energy. Large amounts of wind energy and the RTO energy markets have increased the need for transmission to deliver energy off peak and improve the efficiency of the energy markets. Papers and reports have been written that describe the use of generation optimization and power system...
The complex system architecture required to support smart grid technology introduces an undetermined level of risk in power systems. Many current techniques to evaluate cyber specific risk fail to scale to such a large environment. While attack graphs and trees are frequently used to model system security, both approaches require the ability to predict potential attack vectors. Access graphs have...
Utilities world over use decision support tools based on in-premise software with standalone architecture and suffer vulnerability when needing to extend their application to meet new business requirements. Accessibility of these applications are limited to specific operating environments resulting in restricted information being available at the right place and time to support decision making. Unlike...
This paper presents the results of developing a magnetic field sensor that measures the air-gap flux inside an operating switched reluctance motor. Employing the giant magnetoresistive (GMR) effect associated with copper-cobalt nanowires, the computation of instantaneous torque in a switched reluctance machine is developed for real-time applications. Consideration is given to the number of sensors...
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