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Nowadays, Romania confronts with a storm of the already implemented projects or in development as regards the wind and photovoltaic power plants, located to a great extent in Dobrogea, an area where the power consumption is low. Also, the capacities of discharge power lines on this area are limited. Compare with the wind power plants, the photovoltaic power plants have a more uniform spreading in the country. A great importance have the aspects that concerns the level where the wind power plants penetrates the National Power System. Considering the practice used in EU countries, which have a high penetration potential of the renewable energy in the National Power System, Romania needs to reorganize the current structure taking into account the adopting of one organizational structure dedicated in that meaning. As follows, there are presented a number of solutions to be adopted for this purpose.

The increasing share of renewable energy sources for electricity, driven by variable output technologies such as wind and solar photovoltaics, is expected to have an impact on the operational reserve requirements of power systems. This study applies a probabilistic approach to estimate reserve requirements and establishes a methodology that makes it possible to distinguish between different categories of reserves based on the imbalance drivers of wind power. The methodology is based on sizing fast-response reserves based on the distribution of output fluctuations inside the settlement period, and sizing slow-response reserves based on the distribution of the average prediction error over the settlement period. The main advantage of this methodology is a reduction of the fast-response reserves, which are generally assessed as expensive compared to slow-response reserves. This approach is applied in a case study and compared with alternative strategies. The results for 500 MW of wind power installed in a North Sea country confirm these reductions and show that with the suggested approach the required fast-response and slow-response reserves, respectively, amount to 7 and 23–26% of the installed wind power capacity.

How much capacity credit should be given to wind power in generation system adequacy analysis is a question of great interest around the world. Both a theoretical analysis and an accurate evaluation on the wind power capacity credit are essential for understanding its contribution to power system reliability. Current evaluation techniques usually rely on numerical calculation procedures that do not provide an analytical analysis, or are based on assumptions that are valid only for small wind penetration. This study presents a rigorous model based on the definition of the reliability function. The derivation of the model is presented and a fast and accurate method for calculating the capacity credit is developed based on this model. The proposed method does not require strong hypotheses and is thus widely applicable, especially when current evaluation techniques might cause large errors, for example, when the wind power penetration is large and the wind power and load profile are not statistically independent. The model is used to explain how the statistical characteristics of the load and wind power affect the capacity credit, from both a statistical and chronological perspective. Numerical tests demonstrate the correctness of the proposed model and its potential applicability under different circumstances.

As a renewable energy source, wind energy has been rapidly developed in the current exhaustion and lack of energy. However, while wind power construction is developing rapidly, the wind curtailment phenomenon caused by the difficult problem of transportation and consumption is also becoming more and more popular. Seriously, it caused a lot of waste of energy. This paper introduces the background of the cause of abandoning wind and the development status of abandoned wind power generation at home and abroad. Combined with a large number of related researches, it analyzes the prospects of abandon wind power generation operation and evaluates the development prospect of wind power heating. Finally, the development of abandoned wind heating has been prospected.

The development of wind-and solar-generating capacity is growing rapidly around the world as policy makers pursue various energy policy objectives. This paper will describe the challenges in integrating wind and solar generation, the lessons learned, and recommended strategies from both operating experience and integration studies. Case studies on the experience with wind and solar integration in China, Germany, and Spain are also included in this paper. The paper is organized as follows. First section summarizes worldwide wind and solar development, the challenges in integrating wind and solar generation, and some of the lessons learned from studies designed to evaluate the impact of higher levels of wind and solar generation and also from the operational experience in some countries with larger amounts of renewable energy. The second section summarizes some of the solutions for incorporating higher levels of wind and solar capacity into short-term system operations. This section also explains basic methodologies to implement system operations studies to understand the impacts of variability in system operation. The third section explains the contribution of variable renewables to long-term supply adequacy-commonly called 'firm' power-and the relationship of this to long-term reserves; it also explores how these issues can be incorporated into long-term planning or adequacy assessments. Overall, the variability of wind power generation adds to the variability on the grid in most time scales, and a key question that wind integration studies must address is whether there is enough existing capability on the grid to manage that increased variability, or whether new sources, such as new generation or increased levels of demand response, must be added to manage that variability.

The purpose of this report is to provide decision makers in Colombia (and by extension other countries or regions), who are considering the deployment or consolidation of wind power, with a set of options to promote its use. The options presented are the result of an analysis of the Colombian market; this analysis included simulations and modeling of the country's power sector, and extensive consultations with operators, managers, and agents. More information on the analysis and simulations is presented in the appendixes. Wind was chosen to exemplify the range of renewable energy alternatives available to complement traditional power sector technologies on the basis of its technical maturity, its relatively low cost compared to other options, the country's experience, and its wind power potential. This report constitutes the second phase of a barrier analysis to wind energy in Colombia.

Power conversion interface for small-capacity wind power generation system based on permanent-magnet synchronous generator (PMSG) is proposed in this paper. The proposed power conversion interface will convert the wind power generated from the three-phase PMSG to a high quality power to inject into the single-phase utility. This power conversion interface comprises of a power converter and a zero-sequence transformer set. The power converter is controlled to generate a set of positive-sequence currents to absorb a real power from the three-phase PMSG and a set of zero-sequence currents to pass through the zero-sequence transformer set to the single-phase utility. A feed-forward control is used to control the proposed power conversion interface so as to simplify the control circuit. A simplified maximum power point tracking method is also proposed and incorporated in the control circuit of the power conversion interface to extract the maximum power of the PMSG-based wind power generation system. Hence, the proposed power conversion interface has the advantages of simplifying both the power circuit and the control circuit. A prototype is developed to demonstrate the performance of the proposed power conversion interface. The experimental results show that the proposed power conversion interface can achieve the expected performance.

The impacts of wind disturbance on voltage regulation and frequency regulation of power system were studied. The opinion that the regulation of power flow on the tie lines between the grids constrains the integrated capacity of wind power was put forward. Based on the real condition of Inner Mongolia power grid, an engineering practical method was put forward to calculate the integrated capacity of wind power under this constraint. The relationship between wind power and spinning reserve and the impacts of other related factors on the capacity of wind power were studied as well. The impact of wind disturbance on voltage stability where the wind farms are located was studied.

It studies the impacts of the wind speed disturbance such as the gradient wind and gust on the active power, reactive power and voltage of the system. In the process of wind speed disturbance, double fed wind turbine increases or reduces the reactive output of wind turbine timely according to the changes of system voltage, ensure the machine terminal voltage to operate in the normal range .

Scaling up renewable energy, such as wind and solar, goes hand-in-hand with the expansion of transmission infrastructure. The richest solar and wind renewable energy sites are often located far away from consumption centers or existing transmission networks. Unlike fossil fuel-based power sources, renewable energy sources are greatly site-constrained and, for this reason, transmission networks need to be expanded to reach the renewable energy sites. Delivering transmission is a challenge, given the dispersion and granularity of renewable sources. Tapping a few hundred megawatts of renewable energy sources, such as wind and solar power, will likely require delivering transmission to several sites. Furthermore, transmission is also required to smooth out the variability of new renewable sources in a large geographical area. For these reasons, countries' renewable energy scale-up efforts are being challenged by the need for timely and efficient delivery of transmission networks. The objective of this report is to present emerging lessons and recommendations on approaches to efficiently and effectively expand transmission networks for renewable energy scale-up. The report focuses on the planning and regulatory aspects of transmission expansion that are relevant to transmission utilities and electricity regulators.