Engineering topics

Samaan, Nader A

Publications and source records attributed to Samaan, Nader A.

5 records

DOE OSTI2013

Standardized Software for Wind Load Forecast Error Analyses and Predictions Based on Wavelet-ARIMA Models - Applications at Multiple Geographically Distributed Wind Farms

Given the multi-scale variability and uncertainty of wind generation and forecast errors, it is a natural choice to use time-frequency representation (TFR) as a view of the corresponding time series represented over both time and frequency. Here we use wavelet transform (WT) to expand the signal in terms of wavelet functions which are localized in both time and frequency. Each WT component is more stationary and has consistent auto-correlation pattern. We combined wavelet analyses with time series forecast approaches such as ARIMA, and tested the approach at three different wind farms located far away from each other. The prediction capability is satisfactory -- the day-ahead prediction of errors match the original error values very well, including the patterns. The observations are well located within the predictive intervals. Integrating our wavelet-ARIMA (‘stochastic’) model with the weather forecast model (‘deterministic’) will improve our ability significantly to predict wind power generation and reduce predictive uncertainty.

uncertainty analysis, wind generation forecast, wa↗

DOE OSTI2013

Different Factors Affecting Short Circuit Behavior of a Wind Power Plant

A wind power plant consists of a large number of turbines interconnected by underground cable. A pad-mount transformer at each turbine steps up the voltage from generating voltage (690 V) to a medium voltage (34.5 kV). All turbines in the plant are connected to the substation transformer where the voltage is stepped up to the transmission level. An important aspect of wind power plant (WPP) impact studies is to evaluate the short-circuit (SC) current contribution of the plant into the transmission network under different fault conditions. This task can be challenging to protection engineers due to the topology differences between different types of wind turbine generators (WTGs) and the conventional generating units. This paper investigates the short circuit behavior of a wind power plant for different types of faults. The impact of wind turbine types, the transformer configuration, and the reactive compensation capacitor will be investigated. The voltage response at different buses will be observed. Finally, the SC line currents will be presented along with its symmetrical components.

Fault contribution, induction generator, protectio↗

DOE OSTI2012

Planning for Variable Generation Integration through Balancing Authorities Consolidation

As more and more variable generation is integrated into power grids, many challenges and concerns arise for an individual balancing authority (BA) to balance the system with limited resources. Consolidating balancing authorities provides a promising method to mitigate these problems by enabling the sharing of resources through operating different BAs as a single BA. The diversity in load and renewable generation over a wide area can be effectively leveraged, which makes it possible to achieve significant savings in balancing requirements. This paper develops a detailed procedure to compute savings in load following and regulation service requirements due to BAs consolidation. It proposes several evaluation metrics for demonstrating the benefits of BA consolidation. Several study scenarios are designed for a set of BAs in the western United States to test the proposed procedure. Results have shown significant savings in the capacity, ramp rate, and energy of balancing service requirements. Important factors affecting the savings, such as forecast accuracy and cross correlation between forecast errors, are also discussed.

Diao, Ruisheng↗

DOE OSTI2012

Overview of Common Mode Outages in Power Systems

This paper is a result of ongoing activity carried out by Probability Applications for Common Mode Events (PACME) Task Force under the Reliability Risk and Probability Applications (RRPA) Subcommittee. The paper is intended to constitute a valid source of information and references about dealing with common-mode outages in power systems reliability analysis. This effort involves reviewing published literature and presenting state-of-the-art research and practical applications in the area of common-mode outages. Evaluation of available outage statistics show that there is a definite need for collective effort from academia and industry to not only recommended procedures for data collection and monitoring but also to provide appropriate mathematical models to assess such events.

Common mode outages↗

DOE OSTI2012

Capacity Value of Solar Power

Evaluating the capacity value of renewable energy sources can pose significant challenges due to their variable and uncertain nature. In this paper the capacity value of solar power is investigated. Solar capacity value metrics and their associated calculation methodologies are reviewed and several solar capacity studies are summarized. The differences between wind and solar power are examined, the economic importance of solar capacity value is discussed and other assessments and recommendations are presented.

Duignan, Roisin↗