An approach is proposed to the modelling of wind farms in the electric power system long-term planning. It allows a specialist to perform calculations based on scanty information and offers a set of ready-to-use data for easy, fast, and precise modelling. The authors exemplify the calculations of wind speed probability density and power curves and give an idea for relevant corrections. They also show how to pass from a single wind turbine model to the unified model of multiple wind turbines which would meet the requirements of long-term planning tasks. The paper presents the data on wind farms that are operating in UK and Oceania
The main objective of the paper is to present an innovative complex approach to distributed generation planning and show the advantages over existing methods. The approach will be most suitable for DNOs and authorities and has specific calculation targets to support the decision-making process. The method can be used for complex distribution networks with different arrangement and legal base.
The paper focuses on the application of synchrophasor measurements that present unprecedented benefits compared to SCADA systems in order to facilitate the successful transformation of the Nordic-Baltic-and-European electric power system to operate with large amounts of renewable energy sources and improve situational awareness of the power system. The article describes new functionalities of visualisation tools to estimate a grid inertia level in real time with monitoring results between Nordic and Baltic power systems.
Basic Principles of Electrical Network Reliability Optimization in Liberalised Electricity Market
The authors propose to select long-term solutions to the reliability problems of electrical networks in the stage of development planning. The guide lines or basic principles of such optimization are: 1) its dynamical nature; 2) development sustainability; 3) integrated solution of the problems of network development and electricity supply reliability; 4) consideration of information uncertainty; 5) concurrent consideration of the network and generation development problems; 6) application of specialized information technologies; 7) definition of requirements for independent electricity producers. In the article, the major aspects of liberalized electricity market, its functions and tasks are reviewed, with emphasis placed on the optimization of electrical network development as a significant component of sustainable management of power systems.
The article presents an overview of the current situation of awareness of the Latvian citizens in the field of state-of-the-art energy-saving technologies. The authors present a wide range of data obtained as a result of a survey on the attitude of residents to new technologies and readiness to follow the development trends of a smart city.
The article contains the analysis and recommendations for improving the efficiency of introducing new energy-saving and energy-efficient technologies into each household in order to create the most favourable conditions for the implementation of long-term plans for the development of smart cities in Latvia.
This paper presents a mathematical model with continuous variables for brushless exciter system of synchronous machines, containing the thyristor elements. Discrete Laplace transform is used for transition from a mathematical model of a system with variable structure in continuous variables to equation finite difference with permanent structure. Then inverse transition is made to a mathematical model in continuous variables with permanent structure.
The authors propose methods for estimation of the potential of riverflows for electricity production at hydrokinetic power plants. The methods can be applied to any river or its span where it is possible to move using a floating means. The methodical part includes validation of the flow velocity and bed depth measurement data using the available statistics as well as a case study. Analysis of the in-river measurement results for the selected spans of river Daugava shows that the flow rate variations exert only a minor influence on the flow velocity at particular sites. This testifies the hydrokinetic power plants as stable and predictable sources of electrical energy, both in a long term and, especially, in a short one. The proposed estimation methods could be useful in explorations of rivers, making them simpler and cheaper.
The operational conditions of new networks dictate new requirements for the transmission planning, which would include the electricity market figures and a sizable involvement of renewable generation. This paper focuses on the transmission expansion planning techniques based on the calculations of optimal power flows and on the concept of development planning and sustainability. A description is given for the mathematical model of calculations and analysis of transmission system. The results have shown that the Baltic transmission system infrastructure can successfully be analyzed based on the proposed methodology and developed mathematical model
This paper analyses demand side management (DSM) projects and stakeholders’ experience with the aim to develop, promote and adapt smart grid tehnologies in Latvia. The research aims at identifying possible system service posibilites, including demand response (DR) and determining the appropriate market design for such type of services to be implemented at the Baltic power system level, with the cooperation of distribution system operator (DSO) and transmission system operator (TSO). This paper is prepared as an extract from the global smart grid best practices, smart solutions and business models.
In the modern world, many cities make use of state-of-the-art technologies for a diversity of applications. A field with very specific needs is the electric power system that deals with both large entities that govern themselves (grid operators) and the citizens. For both and all actors in between, there is an increased need for information. Steps to provide these data are always taken and several initiatives are ongoing across the world to equip residential users with last generation smart meters. However, a full deployment is still not possible. Considering this aspect, the authors propose KPIs for the specific situation when some information is available from the meters and other sources, but some is not. The study case is based on a residential area occupied mainly by university students and after an extensive measurement campaign the results have been studied and analysis methods proposed.