For several years now it has been indicated by the scientific research that human activity has a definite impact on the temperature of the Earth. There are different ways of reducing anthropogenic climate change, to consume less energy for instance, but also to use renewable sources of energy. Since the wind power market is growing rapidly lately, it seemed interesting to compare how different countries have developed wind power energy and how they intend to do it in the future. Sweden has developed wind power energy for a long time and since Québec, a Canadian province, is similar to the Scandinavian country in many aspects; it was interesting to determine if the province of Québec in Canada can learn from Sweden in the field of wind power energy. When looking to stimulate wind power on their respective territories, it seems that Sweden and Québec have very different approaches to the development of that energy. In Québec, the governmental policy is criticised because it gives too much latitude to private companies when it is almost the opposite in Sweden, where the government is charged to have introduced too many restrictions and environmental policies that hinder the development of wind power. The conclusion is that Québec can learn from Sweden and from Sweden’s mistakes in the wind energy sector, but also from more successful countries like Denmark and Germany. First, Québec could benefit from having a more decentralised development strategy i.e. giving more power to local authorities and local populations. Second, Québec needs stronger economic incentives providing a stable market for developers.

Renewable energy policies, such as the Renewable Portfolio Standard, arising from increasing environmental concerns have set very ambitious targets for wind power penetration in electric power systems throughout the world. In many cases, the geographical locations with good wind resources are not close to the main load centers. It becomes extremely important to assess adequate transmission facility to deliver wind power to the power grid. <p>Wind is a highly variable energy source, and therefore, transmission system planning for wind delivery is very different from conventional transmission planning. Most electric power utilities use a deterministic n-1 criterion in transmission system planning. Deterministic methods cannot recognize the random nature of wind variation that dictates the power generated from wind power sources. This thesis presents probabilistic method to evaluate the contribution of a wind power delivery system to the overall system reliability. The effects of site-specific wind regime, system load, transmission line unavailability, and redundancy on system reliability were studied using a basic system model. The developed method responds to the various system parameters and is capable of assessing the actual system risks. <p>Modern power system aims to provide reliable as well as cost effective power supply to its consumers. Reliability benefits, environmental benefits and operating cost savings from wind power integration should be compared with the associated investment costs in order to determine optimum transmission facility for wind power delivery. This thesis presents the reliability/cost techniques for determining appropriate transmission line capacity to connect a wind farm to a power grid. The effect of transmission system cost, line length, wind regime, wind penetration and customer interruption cost on the optimum transmission line sizing were studied using a basic system model. The methodology and results presented in this thesis should be useful in transmission system planning for delivering wind power to a power system.

The development and utilization of wind energy for satisfying electrical demand has received considerable attention in recent years due to its tremendous environmental, social and economic benefits, together with public support and government incentives. Electric power generation from wind energy behaves quite differently from that of conventional sources. The fundamentally different operating characteristics of wind energy facilities therefore affect power system reliability in a different manner than those of conventional systems. The reliability impact of such a highly variable energy source is an important aspect that must be assessed when the wind power penetration is significant. The focus of the research described in this thesis is on the utilization of state sampling Monte Carlo simulation in wind integrated bulk electric system reliability analysis and the application of these concepts in system planning and decision making. Load forecast uncertainty is an important factor in long range planning and system development. This thesis describes two approximate approaches developed to reduce the number of steps in a load duration curve which includes load forecast uncertainty, and to provide reasonably accurate generating and bulk system reliability index predictions. The developed approaches are illustrated by application to two composite test systems.<p> A method of generating correlated random numbers with uniform distributions and a specified correlation coefficient in the state sampling method is proposed and used to conduct adequacy assessment in generating systems and in bulk electric systems containing correlated wind farms in this thesis. The studies described show that it is possible to use the state sampling Monte Carlo simulation technique to quantitatively assess the reliability implications associated with adding wind power to a composite generation and transmission system including the effects of multiple correlated wind sites. This is an important development as it permits correlated wind farms to be incorporated in large practical system studies without requiring excessive increases in computer solution time. The procedures described in this thesis for creating monthly and seasonal wind farm models should prove useful in situations where time period models are required to incorporate scheduled maintenance of generation and transmission facilities.<p> There is growing interest in combining deterministic considerations with probabilistic assessment in order to evaluate the quantitative system risk and conduct bulk power system planning. A relatively new approach that incorporates deterministic and probabilistic considerations in a single risk assessment framework has been designated as the joint deterministic-probabilistic approach. The research work described in this thesis illustrates that the joint deterministic-probabilistic approach can be effectively used to integrate wind power in bulk electric system planning. The studies described in this thesis show that the application of the joint deterministic-probabilistic method provides more stringent results for a system with wind power than the traditional deterministic N-1 method because the joint deterministic-probabilistic technique is driven by the deterministic N-1 criterion with an added probabilistic perspective which recognizes the power output characteristics of a wind turbine generator.

High-quality short-term forecasts of wind speed are vital to making wind power a more reliable energy source. Gneiting et al. (2006) have introduced a model for the average wind speed two hours ahead based on both spatial and temporal information. The forecasts produced by this model are accurate, and subject to accuracy, the predictive distribution is sharp, i.e., highly concentrated around its center. However, this model is split into nonunique regimes based on the wind direction at an off-site location. This work both generalizes and improves upon this model by treating wind direction as a circular variable and including it in the model. It is robust in many experiments, such as predicting at new locations. This is compared with the more common approach of modeling wind speeds and directions in the Cartesian space and use a skew-t distribution for the errors. The quality of the predictions from all of these models can be more realistically assessed with a loss measure that depends upon the power curve relating wind speed to power output. This proposed loss measure yields more insight into the true value of each model's predictions. One method of evaluating time series forecasts, such as wind speed forecasts, is to test the null hypothesis of no difference in the accuracy of two competing sets of forecasts. Diebold and Mariano (1995) proposed a test in this setting that has been extended and widely applied. It allows the researcher to specify a wide variety of loss functions, and the forecast errors can be non-Gaussian, nonzero mean, serially correlated, and contemporaneously correlated. In this work, a similar unconditional test of forecast accuracy for spatial data is proposed. The forecast errors are no longer potentially serially correlated but spatially correlated. Simulations will illustrate the properties of this test, and an example with daily average wind speeds measured at over 100 locations in Oklahoma will demonstrate its use. This test is compared with a wavelet-based method introduced by Shen et al. (2002) in which the presence of a spatial signal at each location in the dataset is tested.

In response to the global climate change and environmental protection needs, more and more nations take renewable energies as one of the major future energy policies for its characteristics of clean, low greenhouse gas emission and self-productivity. Among Taiwan¡¦s many renewable energy development, wind energy is always on the list. Wind energy will not only avoid the problems of carbon dioxide which cause greenhouse effect, but also refrain pollution caused by fossil fuel or nuclear energy. The induction generator is a fundamental component of a wind machine. It¡¦s electric port and control can be classified into single fed control and double fed control. Through various comparisons of control and operation, double fed control seems to be more stable at present. Double fed induction generator may continuously produce power at island state without the supply of reactive power from parallel capacitor or the synchronous generator. which is the biggest advantage than single fed induction. , In other words, double fed induction generator may supply power independently. The induction generator is a time-varying and non-linear component. So the traditional rule of scalar control is not adopted in the thesis. The induction generator can be linearized by using vector control, and the power flow can also be directed with the control of its composition of rotor current vector and the controller is designed under the above methodology. The thesis aims to simulate, analyze and compare the steady and transient states of single fed and double fed wind generators with the purposes a more through understanding of the controller and its operation.

This thesis derives the proper load shedding scheme for a distribution system with wind power generating units to maintain the power supply reliability for the islanding operation of micro grid systems after fault disturbance. The comparison of operation performance and control scheme between the fixed speed and the variable speed wind power generators are made. The seasonal wind power energy by the wind turbine is calculated by applying the exponential rate (Power Law) and Weibull possibility distribution model with the actual minutely wind speed data in Hengchun and Penghu area in 2005. The mean values of seasonal wind power output and standard deviation are determined for the design of load shedding scheme for the islanding operation of the distribution feeder. Moreover, a practical distribution feeder BX31 in Fengshan District in Taiwan Power Company (TPC) is selected for the computer simulation of micro grid systems. The systems voltage and power variation of the distribution feeder are investigated when the wind turbine is connected to the feeder by considering the weekday and weekend load models. The voltage sag on the distribution feeder and transient stability of wind turbine are simulated for the fault contingency with three-phase short-circuit fault occurred on the feeder outlet. Consequently, synchronous condensers are connected and the blade angle of wind turbines is then adjusted to improve the transient response of output characteristic of wind turbine. It is found that the power supply reliability of micro grid with wind power generations will be deteriorated following the tripping of wind turbines due to the oscillation of terminal voltage introduced by long fault clearing time. To solve the problem, the proper design of the tripping for the micro grid systems with wind turbines is derived according to the transient stability analysis. To restore the systems stability of the islanding systems, the proper amount of load shedding is determined and the switching of control modes of the wind turbine is executed, according to the power mismatch between wind turbine generation and load demand of the distribution feeder.

Master's thesis. / Format: PDF. Bibl.

Forecasting capital expenditures in early stages of an offshore wind power project is aproblematic process. The process can be affected by optimism bias and strategicmisrepresentation which may result in cost overruns. This thesis is a response to issuesregarding cost overruns in offshore wind power projects. The aim of this thesis is tocreate a cost forecasting method which can estimate the necessary capital budget in awind power project. The author presents a two-step model which both applies the inside view and outsideview. The inside view contains equations related to investment and installation costs.The outside view applies reference class forecasting in order to adjust the necessary costcontingency budget. The combined model will therefore forecast capital expenditures fora specific site and adjust the cost calculations with regard to previous similar projects. The results illustrate that the model is well correlated with normalized cost estimationsin other projects. A hypothetical 150MW offshore wind farm is estimated to costbetween 2.9 million €/MW and 3.5 million €/MW depending on the location of the windfarm.

Σκοπός της παρούσης διπλωματικής εργασίας είναι η μελέτη μιας ανεμογεννήτριας με επαγωγική μηχανή δακτυλιοφόρου δρομέα με διασύνδεση συνεχούς ρεύματος στο δίκτυο. Η διασύνδεση συνεχούς ρεύματος αποτελείται από έναν πυκνωτή που είναι συνδεδεμένος με την πλευρά της μηχανής μέσω ενός ac/dc πλήρως ελεγχόμενου ανορθωτή ισχύος ενώ με την πλευρά του δικτύου συνδέεται μέσω ενός dc/ac πλήρως ελεγχόμενου αντιστροφέα ισχύος. Ο πυκνωτής , ο ανορθωτής και ο αντιστροφέας είναι συνδεδεμένοι σε σειρά και αποτελούν την dc διασύνδεση. Η μελέτη γίνεται αρχικά με την θεωρητική ανάλυση του συστήματος της ανεμογεννήτριας. Για την θεωρητική ανάλυση χρησιμοποιείται για διευκόλυνση ο μετασχηματισμός Park που μετασχηματίζει το τριφασικό a-b-c σύστημα των εξισώσεων του συστήματος στο d-q πλαίσιο αναφοράς. Η ανάλυση μας οδηγεί στην εξαγωγή των εξισώσεων στον χώρο κατάστασης και έτσι οδηγούμαστε στο μαθηματικό μοντέλο του συστήματος. Στην συνέχεια παρουσιάζεται η θεωρία ελέγχου του συστήματος της επαγωγικής γεννήτριας και γίνεται ο προσδιορισμός των κερδών των cascaded PI ελεγκτών. Στο τελικό στάδιο της διπλωματικής εργασίας γίνεται η προσομοίωση του συστήματος και της συμπεριφοράς του κατά την μεταβολή του ανέμου. Ο άνεμος στην πρώτη περίπτωση μεταβάλλεται βηματικά και στην δεύτερη περίπτωση με τυχαίο τρόπο. Με την χρήση του λογισμικού Simulink του Matlab εξάγουμε τις γραφικές παραστάσεις των χαρακτηριστικών μεγεθών : ρευμάτων, τάσεων, ροών, ισχύων του συστήματος και παρατηρώντας τα αποτελέσματα αυτών καταλήγουμε σε σχετικά συμπεράσματα για το προς μελέτη σύστημα. / The purpose of this thesis is to study a wind turbine with a wound rotor induction generator which is connected to the network with a dc link. The dc link is made of a capacitor which is connected to the side of the machine with a fully controlled ac/dc power rectifier and to the network side with a fully controlled dc/ac inverter. The capacitor, the rectifier and the inverter are connected in series and comprise the dc link. Firstly, it is necessary to begin with the theoretical analysis of the system of the wind turbine. At the system analysis is used the Park transformation that transforms the three-phase a-b-c system of equations at the d-q reference frame. Our analysis leads to be exported the equations in state space which are the mathematical model of the system. Then we present the cascaded PI controller design and the gain tuning for the system of the wound rotor induction generator. In the final stage of the thesis there is the simulation of the system and its behavior during the change of wind. In the first case, the wind change stepwise and in the second case in a random manner. By using the software of Simulink at Matlab we draw the graphs of feature sizes such as: currents , voltages , flows and power of the system and as we observe the results of the graphs we arrive at conclusions about the under study system.

Η παρούσα διπλωματική εργασία κάνει μια ανασκόπηση στην ενεργειακή κατάσταση του πλανήτη και της Ελλάδας. Παρουσιάζει τις εναλλακτικές-ανανεώσιμες μορφές ενέργειας παραγωγής ηλεκτρισμού. Στη συνέχεια, αναλύει τον άνεμο, τα χαρακτηριστικά μεγέθη του, την αιολική ενέργεια, και τις προοπτικές της εγχώρια. Βλέπουμε αναλυτικά τον ανεμοκινητήρα, τους διαφορετικούς τύπους του και τη λειτουργία του. Και καταλήγουμε στο να καθορίσουμε τους τρόπους αξιολόγησης μιας αιολικής εγκατάστασης, εκφράζουμε μαθηματικά τις οικονομικές σχέσεις και παραθέτουμε μια εφαρμογή αιολικής εγκατάστασης που αναλύεται με τα παραπάνω. Τέλος, αναφερόμαστε στο νομοθετικό πλαίσιο αν και ρευστό από έτος σε έτος και στην ισχύουσα διαδικασία εγκατάστασης ενός αιολικού πάρκου. / The present dissertation gives a general review of the situation of energy of the planet and Greece. It presents the alternative-renewable forms of energy for the production of electricity. Afterwards, it analyses the wind, its characteristic sizes, the wind power and its domestic perspectives. We can see in detail the wind engine , its various types and its function. Furthermore, we end up defining the ways evaluating of a wind installation, we express mathematically the financial relations and we not only cite an application of a wind installation which is analysed with the above mentioned ways but we also present the easiest analysis through the computer. Finally, we refer to the legislative scope even though it is unstable from year to year and to the procedure of installation of a wind park which is in effect.