Amro M. Farid

Aramazd Muzhikyan, Steffi O. Muhanji, Galen Moynihan et al.

The bulk electric power system in New England is fundamentally changing. The representation of nuclear, coal and oil generation facilities is set to dramatically fall, and natural gas, wind and solar facilities will come to fill their place. The introduction of variable energy resources (VERs) like solar and wind, however, necessitates fundamental changes in the power grid's dynamic operation. VER forecasts are uncertain and their profiles are intermittent thus requiring greater quantities of operating reserves. This paper describes the methodology and the key findings of the 2017 ISO New England System Operational Analysis and Renewable Energy Integration Study (SOARES). This study was commissioned by the ISO New England stakeholders to investigate the effect of several scenarios of varying generation mix on normal operating reserves. The project was conducted using the holistic assessment approach called the Electric Power Enterprise Control System (EPECS) simulator.The EPECS characterizes a power system in terms of the physical power grid and its multiple layers of control including commitment decisions, economic dispatch, and regulation services. This paper provides precise definitions of how variable energy resources and operating reserves are modeled. It also includes detailed models of the day-ahead resource scheduling, the same-day resource scheduling, the real-time balancing operations and the regulation service. Among the key findings, the reports shows that scenarios with high penetrations of VERs exhaust their operating reserves for part of the year and all scenarios curtail semi-dispatchable resources both to complement operating reserves and to mitigate some of the topological limitations of the system. Overall, curtailment emerges as a key balancing performance control lever and there is a clear need for higher amounts of operating reserves.

Amro M. Farid, Dakota Thompson, Wester Schoonenberg

Recently, hetero-functional graph theory (HFGT) has developed as a means to mathematically model the structure of large-scale complex flexible engineering systems. It does so by fusing concepts from network science and model-based systems engineering (MBSE). For the former, it utilizes multiple graph-based data structures to support a matrix-based quantitative analysis. For the latter, HFGT inherits the heterogeneity of conceptual and ontological constructs found in model-based systems engineering including system form, system function, and system concept. These diverse conceptual constructs indicate multi-dimensional rather than two-dimensional relationships. This paper provides the first tensor-based treatment of hetero-functional graph theory. In particular, it addresses the ``system concept" and the hetero-functional adjacency matrix from the perspective of tensors and introduces the hetero-functional incidence tensor as a new data structure. The tensor-based formulation described in this work makes a stronger tie between HFGT and its ontological foundations in MBSE. Finally, the tensor-based formulation facilitates several analytical results that provide an understanding of the relationships between HFGT and multi-layer networks.