High performance computation tools for real-time security assessment

The need to increase situational awareness in power systems is more evident than before. Increased power system complexity and integration of intermittent resources have contributed to the emerging need to monitor power systems in real time. Real time contingency analysis can increase situational awareness by monitoring the power system in real time and alarming the operators of the impending problems. Monitoring all multiple contingencies in real time is impossible and therefore, there is a need to reduce the number of monitored contingencies. This paper introduces a method for identifying most critical contingencies in power system for real-time monitoring.

Contingency analysis is a key function in the Energy Management System (EMS) to assess the impact of various combinations of power system component failures based on state estimates. Contingency analysis is also extensively used in power market operation for feasibility test of market solutions. Faster analysis of more cases is required to safely and reliably operate today's power grids which have a less margin and more intermittent renewable energy sources. Enabled by the latest development in the computer industry, high performance computing holds the promise of meet the need in the power industry. This paper investigates the potential of high performance computing for massive contingency analysis. The framework of “N-x” contingency analysis is established, and computational load balancing schemes are studied and implemented with high performance computers. Case studies of massive 300,000-contingency-case analysis using the Western Electricity Coordinating Council power grid model are presented to illustrate the application of high performance computing and demonstrate the performance of the framework and computational load balancing schemes.

An architecture of high performance computer,called Hyper Parallel Processing(HPP),is proposed to satisfy the requirements of both High Performance Computing,and Utility Computing which will be the application model of data centers.HPP combines the benefits of the scalability of MPP,the communication efficiency of DSM,as well as the commodity of cluster.Comparisons of current main-stream high performance computer architectures show that none of them can satisfy both HPC and utility computing.The main features of HPP are Global Address Space(GAS) and Hyper Node with single Operating System image.HPP supports the distributed global address space including both memory and I/O,but without hardware cache coherence.A Hyper Node consists of a set of application specific CPUs and a(or more) OS specific CPU.The OS CPU maintains the single system image,while the application CPUs run only lightweight run-time software.Besides the GAS interconnect network for applications,a standard SAN connects all OS CPUs and I/O devices providing system management and storage service.HPP is able to provide many opportunities of innovative research in High Performance and Utility Computing areas,including communication,synchronization,programming model,node operating system,utility computing,fault isolation,CPU and system etc.According to HPP architecture,a prototype system of Dawning5000 HPC is implemented and the feasibility of HPP is proved.

For decades, HPC has established itself as an essential tool for discoveries, innovations and new insights in science, research and development, engineering and business across a wide range of application areas in academia and industry. Today High-Performance Computing is also well recognized to be of strategic and economic value – HPC matters and is transforming industries. This article will discuss new emerging technologies that are being developed for all areas of HPC: compute/processing, memory and storage, interconnect fabric, I/O and software to address the ongoing challenges in HPC such as balanced architecture, energy efficient high-performance, density, reliability, sustainability, and last but not least ease-of-use. Of specific interest are the challenges and opportunities for the next frontier in HPC envisioned around the 2020 timeframe: ExaFlops computing. We will also outline the new and emerging area of High Performance Data Analytics, Big Data Analytics using HPC, and discuss the emerging new delivery mechanism for HPC - HPC in the Cloud.

This open access book is the final compendium of case studies emanated from the 4-year COST Action IC1406 “High-Performance Modelling and Simulation for Big Data Applications” (cHiPSet). Funded by the European Commission from 2015, cHiPSet has created a sustainable reference network linking applied research in High Performance Computing (HPC) and Modelling & Simulation to tangibly address Big Data challenges. cHiPSet has enabled research partnerships for dozens of academics and industry practitioners located in 34 COST countries, as well as in Australia, Belarus, Brazil, China, Russia, and the USA. As a cooperation framework, cHiPSet has reached out to new audiences such as ICT professionals, commercial software developers, and the general public. At a time when Big Data has become a common household term, cHiPSet has strived to become a knowledge hub where data-driven HPC meets Modelling & Simulation. cHiPSet has also endeavoured to use and exploit results through Open Science practices, i.e., open access publication, open access to data repositories, and open-source software development. A testament to this philosophy, this compendium is set to become a required reference for the fast-changing fields of HPC, Big Data, and Modelling & Simulation.

During last years, the Italian Electricity Market has seen important changes, aimed at reducing the cost for consumers as well as at improving efficiency and transparency. In this context, the Ancillary Services and Balancing Market (MSD) is operated by the Italian Transmission System Operator, Terna, to procure resources to relieve grid congestion, to build operational reserve and to balance the power system in real time. This paper describes the structure of the Italian Electricity Market, with a detailed presentation of the MSD that must be economically efficient while meeting the power system reliability standards. Reconciliation of economics and physics in MSD has been obtained by coupling the MSD clearing engine with a contingency analysis tool. The benefits of these decision support tools are shown through use cases. A special focus will be given on the combined action of the market clearing re-dispatch and the special protection schemes to reach a reliable operation plan.

The theoretical concept of technological performance has emerged only recently with the publication of Jon McKenzie's Perform or Else: From Discipline to Performance in 2001. McKenzie develops a general theory of performance based around the development of three performance paradigms: cultural performance, organizational performance (or performance management), and technological performance. In his examination of the techno-performance paradigm, he focuses primarily on late twentieth and early twenty-first century 'high performance' technologies such as computers, guided missiles and space shuttles. While he acknowledges that the concept of performance does not apply only to technologies in this period, his analysis implicitly suggests that high performance technologies are a unique invention of the modern age. This essay confronts McKenzie's restriction of techno-performance to the post-WWII period by demonstrating how technologies performed and were seen to perform in the late nineteenth century through a techno-performance reading of Bram Stoker's Dracula (1897). The late Victorian period saw startling innovations in information and communication technology (such as the overseas telegraph, the typewriter, and the gramophone), which were marketed as high performance technologies, though not in those words. To contextualise my reading of Dracula , I examine contemporary Victorian advertisements for communication technologies to demonstrate how such technologies were viewed as high performance products by Victorian advertisers and consumers. Technology in Dracula has usually been read as a metaphor. I employ McKenzie's concept of techno-performance to examine the performative functions of technology in Dracula that have not yet been explored by Victorianist scholarship. McKenzie notes two challenges posed by techno-performance: first, the challenge posed by a developer to his/her technological product, to perform or be classified as obsolete; and, second, the challenge posed by technology to its user to perform or be regarded as outmoded. I argue that Stoker's Dracula takes up both of these challenges. Emergent technologies sometimes perform in unexpected and potentially disruptive ways, much like the space shuttle Challenger cited by McKenzie; at the same time, such technologies oblige their users to perform in unexpected and disruptive ways. This essay examines emergent technologies in Dracula to highlight the relationship between individual and technological performance in the late nineteenth century.

As deputy assistant secretary for research, development, and simulation in the US Department of Energy Office of Defense Programs, Gil Weigand provides programmatic and policy direction for the DoE's nuclear weapons research, development, and simulation work. In partnership with the national labs, he leads the effort to preserve the technology base and develop programs for the surety, reliability, military effectiveness, and credibility of the nation's nuclear-weapons stockpile.Prior to this job, Weigand was deputy assistant secretary for strategic computing and simulation and a senior information officer for the DoE Office of Defense Programs, where he led advanced initiatives in high-performance computer simulation, computation, and communications. In particular, he was responsible for directing the Accelerated Strategic Computing Initiative, which has created leading-edge computational modeling and simulation tools necessary to move from test-based to simulation-based assessment and certification. The ASCI initiative is based on the Comprehensive Test Ban Treaty, an international treaty to move toward no nuclear testing announced by President Bill Clinton on 11 August 1995.Paul Messina now manages ASCI as DoE deputy assistant secretary for advanced simulation and computing for defense programs. He is on a two-year leave from the California Institute of Technology, where he is assistant vice president for scientific computing, a faculty associate in scientific computing, and director of the Center for Advanced Computing Research. He has a joint appointment at the Jet Propulsion Laboratory as manager of high-performance computing. Messina is also on leave from the position of chief architect for the National Partnership for Advanced Computational Infrastructure, where he established and led the Scalable I/O Initiative.Editor-in-chief George Cybenko recently talked to Weigand and Messina about their roles in ASCI and the Alliance Program, and their thoughts about where the high end of computational performance is headed.

While regular algorithms, characterized by operations on dense matrices and arrays, have long been the mainstay of scientific, high-performance computing, irregular algorithms, which feature unpredictable accesses to pointer-based data structures, are becoming increasingly common in high performance computing, arising in graph analysis, data mining and visualization, among other domains. Unfortunately, the defining characteristics of irregular applications, their dynamic, unpredictable, data-dependent access patterns and data layouts, make achieving high performance on large scale systems difficult. Scaling applications to peta- and exa-scale requires carefully controlling communication and data movement and placement, an inherently difficult task when access patterns and data layouts are unpredictable! Most irregular applications that attain high performance must be painstakingly hand-written and hand-tuned, with few common principles or paradigms uniting various implementations and easing future development. Despite the increasing importance of irregular applications, there is little programmer knowledge, and even less compiler ability, devoted to optimizing them. This project aims to solve these problems. By allowing programmers to write irregular applications in high level forms, with at most a few annotations highlighting key structural properties, programmers can focus on developing their algorithms and methods. The compiler and run-time system can take on the tedious task of optimizing the application for execution at large scales, and can automatically provide efficient implementations. This will provide portability and ease maintenance for existing irregular applications, but, more importantly, open up whole new domains of computational science to large-scale, high-performance simulation codes.

Since phasor measurement units (PMU) were invented, there has been growing interest in developing methodologies for improving monitoring, protection and control of power systems in real time. In this study, the authors propose a new methodology, based on graph modelling, to identify coherent groups of generators in a real‐time fashion. The coherent groups are identified with instantaneous values measured from the system through PMUs, and the methodology needs neither setting the number of desired groups nor defining a threshold value since it is based on coupling factors between generators. Moreover, it is proposed a new method for the online definition of areas for islanding when this action is required as the latest emergency control method. The methodology assigns the non‐generation buses to the previously found generators coherent groups considering three criteria: electrical distance to the group of generators, topology, and operational constraints, which are verified by mean of an optimal power flow. The methodology is tested on the IEEE 39‐bus and IEEE 118‐bus test systems. Results show that the real‐time identification of coherent groups and the definition of areas allow the development of islanding strategies with promising results.

In the past power system control, a large number of staff are often required to continuously monitor and control the actual situation of the power system in front of the equipment day and night, so that the power system can work stably and effectively. In the long-term development of the power industry, because the equipment has been in the state of informing operation, there are often some small problems in the whole system. Automatic simulation technology is an important part of power system automation. The automatic simulation technology combined with power system online analysis technology is used to monitor the operation status of the power system in real time. Problems in the operation process of the system can be found at any time and solved in a timely manner, realizing timely self-diagnosis and self repair functions in a real sense. This paper starts with the application of automation technology in power system, analyzes the development trend and practical application of automation technology, and optimizes the application of automation technology in power grid to improve the operation efficiency of power system.

Inertia is an inherent property of the power system and is the basis for ensuring the safe and stable operation of the system. As new energy sources such as wind power and photovoltaics are connected to the grid through power electronic converters, the inertia of the power system continues to decline, posing a serious threat to the frequency stability of the system. In order to prevent the low level of system inertia, improve the stability of the system and reduce the operating cost of the system, it is necessary to clarify the inertial characteristics of the power system and perceive the inertial level of the power system in real time. Therefore, this paper focuses on the problem of inertial identification of the power system. First, the inertial characteristics of the power system are analyzed. Then, according to the rotor swing equation and the measured data of the PMU, an online identification method of the system inertia of the sliding window is proposed. Measured perturbations verify the accuracy of the method.

The existing operator training simulators (OTSs) simulate the slow dynamics of power systems in real time but this limits the capability of simulating accurate dynamic behaviour after a disturbance. A feasibility study for the modelling of real time transient stability behaviour in the OTS is described. The goal was to analyse not only the CPU timing for the OTS simulation cycle with real time transient stability analysis but to also investigate the resulting improvements in the quality of the OTS. The results confirm that the transient stability can be simulated in real time for systems of realistic size on readily available workstations. More importantly, the results show significant differences in the dynamic behaviour when transient stability is simulated, strongly suggesting that the present OTSs do not provide enough accuracy for training under certain conditions.

This paper presents a new approach in adaptive outof-step (OOS) protection settings in power system in real-time. The proposed method uses extended equal area criterion (EEAC) to determine the critical clearing time (CCT) and critical clearing angle (CCA) of the system, which are vital information for OOS protection setting calculation. The dynamic model parameters and the coherency groups of the system for EEAC analysis are determined in real time to ensure that the newly calculated settings suit with the prevalent system operating condition. The effectiveness of the method is demonstrated in a simulated data from 16-machine 68-bus system model.

If the power system falls into an unsteady state, there will be voltage collapse in which the power system will be separated into small systems. Identifying the stability reserve in conformity with a certain practical operation condition is very important for the system management and operation. In fact, the global power system issue has caused serious outages due to voltage collapse such as in the United States-Canada in August 14, 2003; South London in August 28, 2003; southern Sweden and eastern Denmark in September 23, 2003; and Italy on September 28, 2003, and in Vietnam where power system problem led to power loss on 17 May 2005, 27 December 2006, 20 July 2007, and 10 September 2007. The analysis shows that the phenomenon is related to the loss of system stability. Thus, the operational system as well as the power system designs should be studied related to the issue of the system stability. To study the static stability of the power system, different approximate standards, called pragmatic criteria, were examined. Markovits has investigated the application of the standard of dP/dd to test the stability of the power button and dq/dU to check the voltage stability of the load button [1]. However, the storage stability when calculating standard dP/d d is usually much larger than the reserves when calculating standard dq/dU [1]. This paper presents a method to build a possible operation region in the power plane of load bus which works in comply with the stability limit to evaluate the stability reserve of the power system. This method is used to build a program to monitor the stability reserve of IEEE 39 Bus Power System in real time. To monitor the stability reserve of IEEE 39 nodes power system, articles based on the standard dq/dU was used to calculate the assessment. When using standard dq/dU to check for voltage stability load button, the amount of storage stability can be calculated by the following steps: first, transformed replacement scheme Masonry on the schematic rays of the source and node load stability was examined by using Gaussian elimination algorithm [1, 2, 3], then on the basis of ray diagrams the construction work, allowed domain of spare capacity load capacity in space and storage stability for the load button were determined. The GS-ODT program was built on the basis of Gaussian elimination algorithm and stable domain construction work algorithm for Masonic load button by dQ/dU pragmatic criteria. The GS-ODT program has a simple interface and easy to use with the main function is to identify the allowed domain for the load button and thus can assess visually stable reserve still according to the load capacity of the nodes of the IEEE 39 nodes power system in real-time.