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ABSTRACT: A new idea using an analytic hierarchical process (AHP) is
proposed for VAr placement compensation. AHP uses parallel analytical
criteria for selecting and ranking placement of VAr compensation. Due to
their independent nature these criteria are not necessarily the same
although both aim to identify weak nodes in maintaining system voltages.
AHP also considers quantitative criteria. It is especially suitable for
problems that are difficult to analyse. AHP provides a simple,
convenient and comprehensive means of selection and ranking. The
proposed algorithms have been tested on the IEEE 14-bus and 30-bus
systems with satisfactory results. The paper also proposes a new
nonlinear optimisation neural network approach to study the reactive
power problem. The approach is applied to VAr control optimisation, in
which the objective is to minimise the system voltage profile. The
approach is a penalty-minimisation method with weights based on
optimisation theory and neural optimisation methods. It is used to solve
the nonlinear programming problem with equality and inequality
constraints. The paper demonstrates that the energy function used is a
Lyapunov function, and the equilibrium point of the proposed neural
network corresponds to the optimal solution of a constrained
optimisation problem
IEE Proceedings - Generation Transmission and Distribution 02/1998; · 0.48 Impact Factor
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ABSTRACT: This paper presents a new approach to study the energy transaction
scheduling for market-based operation using network flow programming
(NFP). The proposed model includes network constraints and transmission
losses. In the old paradigm, most of the schedules considered bilateral
contracts. Research work showed that a multilateral contract is needed
for efficient market operation. In this study, the proposed method is
based on the premise that there are no firm contracts in the energy
transaction system. Every contract in the energy transaction system is
considered as a multilateral contract. An independent system operator
(ISO) is assumed to be the broker. The broker maximises the number of
transactions subject to power flow equations, buying and selling
contracts and network constraints. This leads to a problem of network
flow programming (NFP) with upper and lower limits. So a special
solution in NFP “out-of-kilter algorithm” (OKA) is employed.
A test example of IEEE 30 bus system is presented for the proposed model
and method
Advances in Power System Control, Operation and Management, 1997. APSCOM-97. Fourth International Conference on (Conf. Publ. No. 450); 12/1997
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ABSTRACT: A fully coupled active and reactive dispatch using linear
programming and an analytic hierarchical process is developed. The
purpose of combined active and reactive dispatch (CARD) is to achieve
the overall objective of minimum generation cost and to improve the
distribution of reactive power and voltage, subject to constraints which
ensure system security. Security is defined as the maintenance of
individual circuit flows, generator reactive power output and system
voltages within limits under normal system conditions and contingency
cases. The weighting factors of different kinds of objective functions
are determined by an analytic hierarchical process (AHP), considering
the relative importance of these objective functions. The developed
method is demonstrated through its application to determine the combined
active and reactive dispatch of a 713-node network representing a
practical power system, provided by the National Grid Company plc (NGC).
The calculation results show that a good balance can be achieved among
the various objectives and a satisfactory generation pattern is obtained
from the enhanced CARD program
IEE Proceedings - Generation Transmission and Distribution 08/1996; · 0.48 Impact Factor
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ABSTRACT: The authors present a novel approach to studying the automatic
contingency selection (ACS). The total curtailment of the reactive loads
is used as the performance index to evaluate the severity of
contingencies. The minimum cost network flow model is proposed to
determine the optimal curtailment in the line outage case. The objective
of the model is the determination of the sum of branch voltage drops in
terms of the line reactive flows. The optimisation model is solved by
the out-of-kilter algorithm. The numerical results for several IEEE
sample systems show that the proposed technique is feasible and
effective
Generation, Transmission and Distribution [see also IEE Proceedings-Generation, Transmission and Distribution], IEE Proceedings C 02/1991;
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ABSTRACT: This article presents a new nonlinear convex network flow programming model and algorithm for solving the on-line economic power dispatch with N and N−1 security. Based on the load flow equations, a new nonlinear convex network flow model for secure economic power dispatch is set up and then transformed into a quadratic programming model, in which the search direction in the space of the flow variables is to be solved. The concept of maximum basis in a network flow graph was introduced so that the constrained quadratic programming model was changed into an unconstrained quadratic programming model which was then solved by the reduced gradient method. The proposed model and its algorithm were examined numerically with an IEEE 30-bus test system on an ALPHA 400 Model 610 machine. Satisfactory results were obtained
