Security Constrained Multi-Stage Transmission Expansion Planning Considering a Continuously Variable Series Reactor

This paper introduces a Continuously Variable Series Reactor (CVSR) to the transmission expansion planning (TEP) problem. The CVSR is a FACTS-like device which has the capability of controlling the overall impedance of the transmission line. However, the cost of the CVSR is about one tenth of a similar rated FACTS device which potentially allows large numbers of devices to be installed. The multi-stage TEP with the CVSR considering the $N-1$ security constraints is formulated as a mixed integer linear programming model. The nonlinear part of the power flow introduced by the variable reactance is linearized by a reformulation technique. To reduce the computational burden for a practical large scale system, a decomposition approach is proposed. The detailed simulation results on the IEEE 24-bus and a more practical Polish 2383-bus system demonstrate the effectiveness of the approach. Moreover, the appropriately allocated CVSRs add flexibility to the TEP problem and allow reduced planning costs. Although the proposed decomposition approach cannot guarantee global optimality, a high level picture of how the network can be planned reliably and economically considering CVSR is achieved.Comment: Accepted by IEEE Transactions on Power System

Mission Control Center enhancement opportunities in the 1990's

The purpose of this paper is to present a framework for understanding the major enhancement opportunities for Air Force Mission Control Center/Test Support Centers (MCC's/TSC's) in the 1990's. Much of this paper is based on the findings of Study 232 and work currently underway in Study 2-6 for the Air Force Systems Command, Space System Division, Network Program Office. In this paper, we will address MCC/TSC enhancement needs primarily from the operator perspective, in terms of the increased capabilities required to improve space operations task performance

Fast Algorithm for N-2 Contingency Problem

We present a novel selection algorithm for N-2 contingency analysis problem. The algorithm is based on the iterative bounding of line outage distribution factors and successive pruning of the set of contingency pair candidates. The selection procedure is non-heuristic, and is certified to identify all events that lead to thermal constraints violations in DC approximation. The complexity of the algorithm is O(N^2) comparable to the complexity of N-1 contingency problem. We validate and test the algorithm on the Polish grid network with around 3000 lines. For this test case two iterations of the pruning procedure reduce the total number of candidate pairs by a factor of almost 1000 from 5 millions line pairs to only 6128.Comment: HICC

Contingency-Constrained Unit Commitment with Post-Contingency Corrective Recourse

We consider the problem of minimizing costs in the generation unit commitment problem, a cornerstone in electric power system operations, while enforcing an N-k-e reliability criterion. This reliability criterion is a generalization of the well-known $N$-$k$ criterion, and dictates that at least $(1-e_ j)$ fraction of the total system demand must be met following the failures of $k$ or fewer system components. We refer to this problem as the Contingency-Constrained Unit Commitment problem, or CCUC. We present a mixed-integer programming formulation of the CCUC that accounts for both transmission and generation element failures. We propose novel cutting plane algorithms that avoid the need to explicitly consider an exponential number of contingencies. Computational studies are performed on several IEEE test systems and a simplified model of the Western US interconnection network, which demonstrate the effectiveness of our proposed methods relative to current state-of-the-art

Impact Assessment of Hypothesized Cyberattacks on Interconnected Bulk Power Systems

The first-ever Ukraine cyberattack on power grid has proven its devastation by hacking into their critical cyber assets. With administrative privileges accessing substation networks/local control centers, one intelligent way of coordinated cyberattacks is to execute a series of disruptive switching executions on multiple substations using compromised supervisory control and data acquisition (SCADA) systems. These actions can cause significant impacts to an interconnected power grid. Unlike the previous power blackouts, such high-impact initiating events can aggravate operating conditions, initiating instability that may lead to system-wide cascading failure. A systemic evaluation of "nightmare" scenarios is highly desirable for asset owners to manage and prioritize the maintenance and investment in protecting their cyberinfrastructure. This survey paper is a conceptual expansion of real-time monitoring, anomaly detection, impact analyses, and mitigation (RAIM) framework that emphasizes on the resulting impacts, both on steady-state and dynamic aspects of power system stability. Hypothetically, we associate the combinatorial analyses of steady state on substations/components outages and dynamics of the sequential switching orders as part of the permutation. The expanded framework includes (1) critical/noncritical combination verification, (2) cascade confirmation, and (3) combination re-evaluation. This paper ends with a discussion of the open issues for metrics and future design pertaining the impact quantification of cyber-related contingencies

A causal model of the impact of the "fuzzy front end" on the success of new product development

In a study of New Product Development (NPD) projects, the fuzzy front end of innovation is explored. The New Product Development process is a multistage process. Therefore, the study examines two sorts of impact that the fuzzy front end has on the success of New Product Development: a direct impact and an indirect impact by influencing the next stage of the NPD process, i.e. project execution. Furthermore, the degree of newness of the NPD projects in accordance with the contingency theory, is considered. We develop and test a causal model of relationships among key variables related to the fuzzy front end, project execution, and success. The causal model is tested with AMOS using information from 144 completed projects from German measurement and control technique firms. For the most part, the responses from these firms support the hypothesized relationships. The frequently claimed importance of the fuzzy front end is confirmed. The results offer strong support for the importance of the early involvement of all functions in an NPD effort to enhance communication and ultimately project success. This can be advanced by a draft initial planning prior to development. Furthermore, the responses highlight the importance of reducing market and particularly technical uncertainty during the fuzzy front end, both of which have a negative influence on communication and increase deviations during project execution. The technical uncertainty that remains at the start of the project has a direct, negative influence on project efficiency and overall it has the most far reaching implications for the success of the project. With regard to contingency theory, the results indicate that effort spent on the reduction of uncertainty for improving project execution and project success may be influenced by the degree of newness. The degree of newness is found to influence the reduction of technical uncertainty, deviations from specifications, and efficiency. Overall, the results of this study support previous research regarding the strong influence that front end activities have on NPD success. The model presented here provides several insights that can help managers to improve their NPD success and inspire researchers to carry out further studies regarding the fuzzy front end. --New Product Development , fuzzy front end

Expert operator's associate: A knowledge based system for spacecraft control

The Expert Operator's Associate (EOA) project is presented which studies the applicability of expert systems for day-to-day space operations. A prototype expert system is developed, which operates on-line with an existing spacecraft control system at the European Space Operations Centre, and functions as an 'operator's assistant' in controlling satellites. The prototype is demonstrated using an existing real-time simulation model of the MARECS-B2 telecommunication satellite. By developing a prototype system, the extent to which reliability and effectivens of operations can be enhanced by AI based support is examined. In addition the study examines the questions of acquisition and representation of the 'knowledge' for such systems, and the feasibility of 'migration' of some (currently) ground-based functions into future spaceborne autonomous systems

Strategic Planning - Niche Marketing in the Agriculture Industry

The purpose of the research is to improve our understanding of the adaptation process in agriculture at the farm level and the influence through the value chain. The research identified critical managerial decision areas in the strategic planning process of blackcurrant growers in Alberta and the South Island of New Zealand. The work was a comparative study of growers that attempted to determine the correspondence between the results of case study observations and a set of theoretical propositions that were developed from a review of the relevant literature. Results indicate that growers understand their own firm’s core competencies, plan strategically and contingently to maintain flexibility and retain niche advantages. Data gathered on the blackcurrant sectors in Canada and New Zealand provided the contextual basis for the selection and analysis of the grower case studies. The sector analysis reached across the value chain. Among the findings reported was the interesting observation that although niche marketing is an accepted strategy in the marketing literature as a means to adaptive change, and although the flexibility inherent in this approach is critical to the success of traditionally resource-starved small firms, it is not clear that the firms reported on in this study engaged in niche marketing as a planned strategy but rather came upon the opportunity through serendipity. In terms of country comparison, results indicate that there may be some specific factors that contribute to the success of the blackcurrant industry in New Zealand. Closer examination of these factors may be beneficial to assisting the Canadian sector. Keywords: Niche marketing, strategic planning, adaptation flexibility JEL Codes: D81, L1, M31, O13, Q13Niche marketing, strategic planning, adaptation flexibility, Farm Management, Marketing, D81, L1, M31, O13, Q13,