The paper presents a Jacobian smoothing nonlinear complementarity method for solving large nonlinear optimal power flow (OPF) problems. By using (smooth or non-smooth) nonlinear complementarity (NC) functions we reformulate the OPF problem as a (smooth or non-smooth) nonlinear system of equations, which, in turn, can be solved by well-known methods. The Jacobian smoothing method computes the se...

In this paper, hybrid particle swarm optimization (PSO) is proposed for solving the challenging multi-contingency transient stability constrained optimal power flow (MC-TSCOPF) problem. The objective of this nonlinear optimization problem is to minimize the total fuel cost of the system and at the same time fulfil the transient stability requirements. The optimal power flow (OPF) with transient...

This paper deals with application of evolutionary algorithm (EA) to solve optimal power flow problem in an efficient manner. In this paper a new approach using cuckoo search (CS) method is proposed for solving OPF problem by optimal setting of control variables. Cuckoo search method is a bio-inspired algorithm based on brooding behaviour of cuckoo birds. This algorithm can search for a global s...

The optimal power-flow problem (OPF) has always played a key role in the planning and operation of power systems. Due to the non-linear nature of the AC power-flow equations, the OPF problem is known to be non-convex, therefore hard to solve. Most proposed methods for solving the OPF rely on approximations (e.g., of the network model) that render the problem convex, but that consequently yield ...

The Optimal Power Flow (OPF) plays an important role in power system operation and control due to depleting energy resources, and increasing power generation cost and ever growing demand for electric energy. As the size of the power system increases, load may be varying. The generators should share the total demand plus losses among themselves. The sharing should be based on the fuel cost of th...

This thesis is concerned with the development of distributed optimization methods with adaptive step-size control and event-triggered communication, where the focus is on convex optimization problems with either nonseparable objective function but separable constraints or separable objective function but couplings in the constraints. Regarding a practice related application of the developed alg...

The paper proposes a security-constrained optimal power flow algorithm (SC-OPF) which allows the post-contingency control of High Voltage Direct Current lines, based on the Voltage Source technology (VSC-HVDC). The presented algorithm integrates corrective actions of HVDC lines in a single optimization problem, without the need to solve a detailed power flow or OPF for each contingency. The app...

This paper present a new computationally efficient improved stochastic algorithm for solving multi-area DC Optimal Power Flow (DC-OPF) in interconnected power systems. This algorithm is based on the combined application of Fuzzy Logic strategy incorporated in Particle Swarm Optimization (PSO) algorithm, hence termed as Fuzzy PSO (FPSO). Multi-area DC-OPF calculations determine optimum generatio...

Voltage stability has become an important issue in planning and operation of many power systems. Contingencies such as unexpected line outages in a stressed system may often result in voltage instability, which may lead to voltage collapse. This paper presents evolutionary algorithm techniques like Genetic Algorithm (GA) and Non-dominated Sorting Genetic Algorithm II (NSGA II) approach for solv...

Different energy infrastructures, such as electricity, natural gas and local district heating systems utilized for the energy supply are most often planned and operated independently of each other. This paper addresses the optimization of combined electricity and natural gas networks. The couplings between the two energy infrastructures are taken into account with the novel concept of energy hu...