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Fault Ride-Through (FRT) is a common requirement to abide by grid code all over the world. In this work, to enhance the fault ride-through capability of fixed speed wind generator system, a modified configuration of Bridge-Type Fault Current Limiter (BFCL) is proposed. To check the effectiveness of the proposed BFCL, its performance is compared with that of the Series Dynamic Braking Resistor (SDBR)...
Forecasting of wind speed and wind power generation is indispensable for the effective operation of a wind farm and the optimal management of revenue and risks. Hybrid forecasting of time series data is considered to be a potentially effective alternative compared with the conventional single forecasting modeling approaches such as autoregressive integrated moving average (ARIMA) and artificial neural...
Wildfires are natural or manmade disaster events that occur in forested and grassland ecosystems. Power transmission lines passing through these areas are in particular vulnerable to wildfires. The heat generated by the fire can increase the surface temperature of the overhead conductors in its vicinity. Extreme surface temperatures can lead to conductor annealing and permanent loss of tensile strength...
As a type of clean and renewable energy source, wind power is being widely used all around the world. However, owing to the uncertainty and instability of the wind power, it is important to build an accurate prediction model for wind power for the grid-connected security operation. The performance of hybrid method is always better than that of single ones in the wind power prediction. Actual wind...
This paper presents an enhanced control scheme for an interior permanent magnet (IPM) synchronous generator based direct drive wind turbine, incorporating maximum torque per ampere trajectory (MTPA) and maximum power extraction (MPE) algorithm. The main advantage of incorporating MTPA trajectory in the control scheme is that it can generate the required torque with a minimum stator current to minimize...
The life time of offshore wind farm is around 20 years. After that, the whole farm should be decommissioned which is also one of the main factors that contribute to the high investment. In order to make a cost-effective wind farm, a novel optimization method for decommission is addressed in this paper. Instead of abandoning the foundations after the wind farm is running out of its life cycle, the...
Distribution feeder reconfiguration is a cost-effective scheme to improve the system operating condition. Making decisions on the status of switches along the feeder with high penetration of renewable resources requires a tractable and accurate input data analysis. This paper presents a method using Gaussian quadrature to approximate probability distribution function of input variables with a probability...
This paper investigates sub-synchronous resonance (SSR) phenomena inside a doubly-fed induction generator (DFIG) based wind farm, considering the impact of the spatial distribution of wind speed. Firstly, the impedance model of a one-DFIG aggregated model based wind farm is presented to analyze the induction generator effect. Then, a two-DFIGs aggregated impedance model, considering DFIGs in both...
The hybrid forecasting algorithm, based on empirical mode decomposition (EMD), has attracted considerable attentions and been widely applied to forecast electricity load, wind speed, and solar irradiation time series (TS). The basic idea of the EMD based method is to decompose the complicated original TS into a collection of sub-series and build specific forecasting models for individual sub-series...
Renewable based distributed generators are being used extensively owing to the benefits they offer for both utilities and investors. With the spread of these DGs in power systems, A precise model that follows the stochastic behavior of wind or solar is crucial for power system planning and operation. This paper presents novel probabilistic models for wind and solar based generators. These models give...
This paper considers two important challenges in the distribution network with high renewable penetrations. One is that during the peak load, generation is normally low or zero and it will cause the voltage drop. Meanwhile, during peak generation period, the generated power will exceed the load and be injected to the grid, which will subsequently cause the voltage rise. This paper proposes a MILP...
Hybrid renewable distributed generation systems are a potential solution to both South Africa's high greenhouse gas emissions and aspirations for universal electrification for remote rural communities. Indigenous resources such biomass, solar and wind are widely available in the country which can preferably be harnessed to supply energy to these communities by implementing hybrid renewable energy...
This paper presents an alternate iterative method to perform AC/DC optimal power flow (AC/DC OPF) calculation considering wind farm integration. Firstly, an original AC/DC OPF model considering wind farm integration is constructed. Then, according to the decoupling theory in the alternate iterative method, the decoupling optimization model of AC/DC OPF model is derived, where the high voltage direct...
It is an important but challenging issue to represent a wind farm using an equivalent model. This paper tries to develop an equivalent representation of a wind farm for power system planning and operation studies using Thevenin equivalent circuit. In the paper, a series string configuration of wind farms with doubly-fed induction generator (DFIG) wind turbines is emphasized, and case studies have...
System Integrity Protection Schemes (SIPS) are being applied to power networks to help ensure their secure operation, particularly when they are operating close to their limits. However, failure of a SIPS to fulfill the reliability requirements of a Power System exposes the system to additional risks that might be unacceptable. A risks assessment procedure is developed in this paper to quantify the...
A key issue in the control of double fed induction generator (DFIG) wind turbine systems is to achieve an expected performance in the presence of stochastic wind speeds. To address this issue, this paper establishes a stochastic model predictive control (SMPC) scheme for the DFIG wind turbine system. The salient feature of this scheme is that it explicitly takes into account the uncertainties in wind...
This paper discusses three approaches to construct wind speed models based on Stochastic Differential Equations (SDEs). The methods are applied to construct models able to simulate wind speed trajectories that are statistically described by means of the Weibull distribution and the exponential autocorrelation. The ability of the three models to reproduce stochastic processes with the above indicated...
The Korean government plans to install 17 GW of wind power capacity by 2027. However, wind farm locations, individual wind farm generation capacities, and the strategies for minimizing wind power variability have not yet been defined. In this paper, the best locations are identified based on annual wind speeds and availability, and the generation capacity of the wind farms at each selected location...
Electric utilities have been using wind power to an increasing extent in order to provide clean energy. However, this resource depends on the intermittency of wind, and this makes balancing supply and demand challenging for the system operator. In this paper we propose a downscaling approach yielding daily probabilistic wind speed scenarios for the turbine hub height, thus making them useful for generating...
In this paper, a mathematical model for calculating the energy yields of offshore wind farm with mixed types of wind turbines is proposed. The Jensen model is selected as the base and developed to a three dimension wake model to estimate the energy yields. Since the wind turbines are with different hub heights, the wind shear effect is also taken into consideration. The results show that the proposed...
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