S.N. Siddiqi

Bio: S.N. Siddiqi is an academic researcher. The author has contributed to research in topics: Power transmission & Electric power system. The author has an hindex of 4, co-authored 4 publications receiving 247 citations.

Advanced pricing in electrical systems. I. Theory

Abstract: This paper sets forth a comprehensive theory for the real-time pricing of electricity that includes selected ancillary services and extends the theory to incorporate constraints on power quality and environment impact that often influence the operation of a power system. This paper is Part I of a two paper set. It sets forth the mathematical development of the extended model for real-time pricing. The formulation is novel in that it combines the dynamic equations for load-frequency control with the static equations of a constrained optimal power flow. Part II derives optimal nodal specific real-time prices for both real and reactive power. The prices derived include additive premia, or opportunity costs, reflecting the effects of voltage regulation, maintenance of generation and transmission reserves, regulation of frequency and tie-line flows, removal and/or control of power harmonics and others.

Advanced pricing in electrical systems. II. Implications

Abstract: Part I of this paper set forth a mathematical formulation of a model for real-time pricing of electricity that included selected ancillary services and extended the theory to incorporate constraints on power quality and environment impact that often influence the operation of a power system. Derived herein are optimal real-time prices for both real and reactive power. The optimal prices are temporally and spatially differentiated. The prices derived include additive premia, or opportunity costs, reflecting the effects of voltage regulation, maintenance of generation and transmission reserves, regulation of frequency and tie-line flows, removal and/or control of power harmonics and others. This paper concludes with a discussion of the implications of the optimal prices for pricing of both retail and wholesale services.

Integrating transmission into IRP part I: analytical approach

Abstract: This is Part I of a two paper set dealing with transmission and integrated resource planning. The primary objective of this paper is to report a framework to bring transmission and selected other resources into the sphere of integrated resource planning. Transmission lines and related equipment are indeed a resource, and may constitute either a substitute for other resources (e.g., a strengthened transmission network may reduce the need for remote generation) or a complement to other resources (e.g., additional transmission investment may be needed to facilitate power purchases from a neighboring system or an independent power producer). Moreover, growing competitive pressures make it necessary to plan transmission systems to facilitate competition among alternative generation and demand-side resources. A combined transmission and integrated resource planning model, called the Comprehensive Electrical Systems Planning Model (CESPLAN), is described in this paper. >

Integrating transmission into IRP part II: case study results

Abstract: This is Part II of a two paper set dealing with transmission and integrated resource planning. Part I described an analytical approach to integrating transmission into the IRP framework and set forth the Comprehensive Electrical Systems planning Model (CESPLAN). The model, a mixed integer, nonlinear, stochastic programming formulation of the planning problem is solved using the generalized Benders decomposition algorithm with importance sampling to couple the contingency state space. The primary objective of this paper is to report a series of case studies performed with the model. Three sets of case study results are reported. The first set illustrates that optimal resource plans created from the commonly used utility approach of two-step planning, i.e., first planning generation and demand-side resources and then determining the set of transmission resources that "best matches" the generation and demand-side plan, can lead to higher costs than when a more comprehensive, integrated planning approach is adopted. A second set of case studies illustrates the use of "importance sampling", a procedure for reducing the number of sample configuration states of the system that must be simulated when estimating the effects of equipment outages on future system operating costs. The third set of studies illustrate not only the optimal generation plan but also the optimal transmission plan is sensitive to planning uncertainties such as emissions allowance costs, customer outage costs, and future natural gas prices. >

Planning for distributed generation

Abstract: Distributed generation (DG) can be incorporated into distribution planning as an option along with traditional feeder and substation options. In place of rigid capacity planning rules, the planning process needs to incorporate more detailed simulations of capacity constraints and customer damage costs because utilities now assume more risk. Planning tools need to simulate load variations, contingencies, dispatch and control action to more accurately determine the capacity limits and related costs. This is especially important when considering DG because the siting and dispatch have an important impact on the benefits to the utility. Equally important is the evaluation of economic risk given uncertainties such as load growth. Because of the added complexities associated with these analysis techniques, the planning process must incorporate appropriate screening tools to determine the depth of analysis needed for particular projects, thereby making more efficient use of already scarce planning resources.

A review of emerging techniques on generation expansion planning

Abstract: Power system generation expansion planning is a challenging problem due to the large-scale, long-term, nonlinear and discrete nature of generation unit size. Since the computation revolution, several emerging techniques have been proposed to solve large scale optimization problems. Many of these techniques have been reported as used in generation expansion planning. This paper describes these emerging optimization techniques (including expert systems, fuzzy logic, neural networks, analytic hierarchy process, network flow, decomposition method, simulated annealing and genetic algorithms) and their potential usage in solving the challenging generation expansion planning in future competitive environments in the power industry. This paper provides useful information and resources for future generation expansion planning.

Locational marginal price sensitivities

Abstract: Within an optimal power flow market clearing framework, this paper provides expressions to compute the sensitivities of locational marginal prices with respect to power demands. Sensitivities with respect to other parameters can also be obtained. An example and a case study are used to illustrate the expressions derived.

Convex Optimization of Power Systems

Abstract: Optimization is ubiquitous in power system engineering. Drawing on powerful, modern tools from convex optimization, this rigorous exposition introduces essential techniques for formulating linear, second-order cone, and semidefinite programming approximations to the canonical optimal power flow problem, which lies at the heart of many different power system optimizations. Convex models in each optimization class are then developed in parallel for a variety of practical applications like unit commitment, generation and transmission planning, and nodal pricing. Presenting classical approximations and modern convex relaxations side-by-side, and a selection of problems and worked examples, this is an invaluable resource for students and researchers from industry and academia in power systems, optimization, and control.