Aleksandar Erdeljan

Software architecture for Smart Metering systems with Virtual Power Plant

This paper presents a novel architecture for Smart Metering systems which enables their seamless, secure and efficient integration in wider SmartGrid software structures. Smart metering solutions represent one of the fastest evolving areas in the field of power distribution systems. There is an extensive interest of leading software vendors in the field, for development of architectures that can efficiently manage transmission, processing and storing of tremendous amount of data produced by such metering devices deployed at the end-end side. The integration of these systems into existing power system software architectures (outage management, workforce management, etc.) represents a major challenge for research community. In such an environment it is of fundamental importance to adopt standardized data exchange mechanisms. The proposed architecture is conceived as modular and scalable structure so that it can support implementation of novel power distribution concepts as Virtual Power Plants (VPPs). The proposed architecture has been successfully tested and verified in real life operation as one of modules of Smart Metering system named Meter Data Management (MDM).

Algorithms in electric power system one-line diagram creation

This paper analyzes various algorithms for the automatic generation of electric power system one-line diagrams. Historically these one-line diagrams were created manually. As these diagrams can be large, their manual creation takes a lot of time and resources, and it is also prone to errors. One possible solution to this problem is the automatic generation of one-line diagrams. Automatic visualization can be performed by existing rule-based algorithms, or if the network is modeled by a mathematical graph, then the problem can also be solved by graph drawing algorithms. Initial results achieved with soft computing algorithms will also be shown. We discuss the similarities, differences and applicability of these different algorithms in automatic one-line diagram generation. The final goal is to find the most suitable algorithm for the automatic generation of visually pleasing one-line diagrams, which allow dispatchers and engineers working in control centers a higher level of efficiency in performing their everyday tasks.

RESTful web services and the Common Information Model (CIM)

This paper shows one possible way to enhance power system software integration by combining RESTful web services (RESTful WS) and the IEC 61970 set of standards. We also discuss the differences between SOAP and RESTful web services in the context of this research. We propose a web service, which wraps the resource oriented power system data model defined in the IEC 61970–301 Common Information Model (CIM) and the generic query interface defined in IEC 61970–403 Generic Data Access (GDA). We will demonstrate that a RESTful WS atop of existing IEC 61970 standards can significantly loose the couplings between different software packages used in power system control centers. We have performed tests on real life power system data models (some used in CIM interoperability tests) to make the tests more realistic. The proposal depicted in this paper provides another powerful tool for creating truly distributed power system software solutions.

Distributed PSO Algorithm for Data Model Partitioning in Power Distribution Systems

This paper presents a method for data model partitioning of power distribution network. Modern DistributionManagement Systems which utilize multiprocessor systems for efficient processing of large data model areconsidered. The data model partitioning is carried out for parallelization of analytical power calculations. The proposedalgorithms (Particle Swarm Optimization (PSO) and distributed PSO algorithms) are applied on data model describinglarge power distribution network. The experimental results of PSO and distributed PSO algorithms are presented.Distributed PSO algorithm achieves significantly better results than the basic PSO algorithm.

A smart metering architecture as a step towards Smart Grid realization

Emerging concept of Smart Grids aims at increasing visibility and controllability of electricity grids boosting their operational efficiency, enabling novel enhanced services to customers and utilities at a same time. Successful realization of this concept will in great part depend on efficient management of tremendous amounts of data to be gathered and processed in very short time periods. In this work we propose a novel smart metering architecture to manage data collected from deployed smart meters logically encapsulated in form of virtual meters. The metering infrastructure is structured in the form of Advanced Metering Infrastructure (AMI). The architecture of Meter Data Management (MDM) system and its integration in Control Center structure of power system is described in details. The testing and verification of proposed solution is performed on real life operation data obtained in collaboration with power distribution company Elektrovojvodina, Serbia.

Algorithm for adaptive Smart Grid visualization

This paper describes an algorithm which automatically generates adaptive one-line diagrams of large electric power distribution systems. The proposed algorithm is different from similar algorithms as it performs adaptive one-line diagram generation, which differ for various zoom levels, showing only the most important objects (e.g. substations, pole switches, power lines) on small zoom levels and gradually adding the less important objects (e.g. lateral parts of the network) as the level of zoom rises, while maintaining the relative positions of the more important objects. The algorithm represents the distribution network as a mathematical graph and visualizes it by utilizing the divide-and-conquer and branch-and-bound algorithms. The algorithm was tested on partial, real life electric power distribution systems of up to 100 objects and it generated visually pleasing one-line diagrams.

A HYBRID GENETIC ALGORITHM FOR PARTITIONING OF DATA MODEL IN DISTRIBUTION MANAGEMENT SYSTEMS

In this paper, we propose a Hybrid Genetic Algorithm for data model partitioning of power distributionnetwork. Analytical functions are the core of Distribution Management Systems (DMSs). Efficient calculation of thefunctions is of the utmost importance for the DMS users; the necessary preconditions for the efficient calculation areoptimal load balancing of processors and data model partitioning among processors. The proposed algorithm is appliedto different real models of power distribution systems. It obtains better results than classical evolutionary algorithms(Genetic Algorithm and Particle Swarm Optimization). The Hybrid Genetic Algorithm also achieves better results thanmultilevel algorithm (METIS) in cases of small graphs. http://dx.doi.org/10.5755/j01.itc.40.4.981

Applicability of RESTful web services in control center software integrations

This paper shows the result of an analysis pertaining to the applicability of RESTful web services (RESTful WS) in solving various software and data integration scenarios in control centers for the electric power system domain. There are many possible ways to enhance power system software/data integration by combining RESTful WS and the IEC 61970 set of standards. The goal of this paper is to highlight those lines of integration in control centers, where the benefits of leveraging RESTful WS are most noticeable. The importance of selecting the most prominent integration scenarios from the viewpoint of RESTful WS stems from the fact, that not all integration problems are naturally fitted for RESTful WS. Assuming a type of RESTful WS, which wraps the resource oriented power system data model defined in the IEC 61970–301 Common Information Model (CIM) and the generic query interface defined in IEC 61970–403 Generic Data Access (GDA), the paper demonstrates that such a RESTful WS may be successfully utilized in many concrete integration situations. As an added advantage, a RESTful WS atop of existing IEC 61970 standards can significantly loose the couplings between different software packages used in power system control centers. We have realized several pilot projects using real life power system data models (some used in CIM interoperability tests) to assert the outcome of our feasibility study. This study clearly shows that RESTful web services are a powerful tool for solving numerous power system software and data integration problems in control centers.

A solution for CIM based integration of Meter Data Management in Control Center of a power system

Modern power systems, in particular Control Center structures, involve more and more software applications in their normal operation. Such scenario urges for standardization of inter and intra processes communication and data exchange. In this work we propose a solution for seamless Meter Data Management (MDM) integration with Control Center structures through Common Information Model (CIM). The solution is implemented in form of a wrapper that adopts messages (i.e. payloads) to the standard requested form. The proposed solution has been verified using a simulation framework which emulates regular control and data flow through predefined set of request patterns.

RESTful access to power system state variables

This paper shows one possible way to enhance power system software integration by leveraging RESTful web services in the process of publishing power system state variables, i.e. the results of simulation functions used in power system analysis.1 Different simulation functions are executed in power system control centers with various goals: optimize network utilization, find critical elements, plan future extensions, etc. Most of these functions base their operation on the results of state estimation and/or load flow. The implementations of these base functions most often come from different software vendors using, in general, different communication mechanisms. Even if the base functions are provided by a sole vendor, the various functions relying on the results of these base functions are most probably offered by different software companies. For this reason, it is necessary to have a standardized method for exchanging state variables between parties. In this paper, we propose a lightweight mechanism, reminiscent to the mechanisms of the World Wide Web, for publishing state variables. The proposition is actually based on existing IEC standards and drafts. The final goal is to allow solution providers to develop a planning and simulation environment for control centers utilizing components made by separate organizations.