Download Title: AN ADAPTIVE NEURO FUZZY POWER SYSTEM STABILIZER

Title: AN ADAPTIVE NEURO FUZZY POWER SYSTEM STABILIZER FOR DAMPING
INTER-AREA OSCILLATIONS IN POWER SYSTEMS
Speaker: Ashwini
Abstract: An Adaptive Neuro-Fuzzy Inference System (ANFIS) based PSS is proposed in this
paper. The controller is essentially divided into two sub-systems, a recursive least square
identifier for the generator and an adaptive neuro fuzzy PSS to damp the oscillations. The PSS is
coupled to a single machine in every area and the parameters of this PSS are tuned online in order
to minimize a cost function. The cost function consists of a summation of terms, in which each
term is made up of the square of the difference in speed between the machine to which the PSS is
connected and another machine in that same area (the number of terms equal the number of
machines in that area excluding the machine installed with a PSS). The PSS is trained to reduce
the speed difference between machines in every area while helping to reduce inter area
oscillations. The proposed technique is illustrated on a 2 area 4-machine 13 bus system. This
ANFIS PSS showed satisfactory performance under severe faulting conditions, where a threephase fault applied to a line, was cleared after a extended period of time. The conventional PSS
and the ANFIS using the original cost function (consisting of just the square of the speed
difference of the generator installed with the PSS) failed to perform under such conditions.
Title 1: Steady Security Assessment Using Linear Programming Methodology
Title 2: Artificial Neural Networks Based Steady State Security Analysis of Power Systems
Speaker: Meera Shukla
Abstract 1:
This paper proposes a new approach to examine the voltage security of the system. An
approximate linear model that comprehensively includes the line flows and bus voltages in its
formulation is the basis for analysis. Linear programming (LP) approach is used to calculate the
load scenarios, which ensures the system security. Forecast of load scenarios that lead to system
security is also possible. The linear programming is implemented using EXCEL Spreadsheet [9].
The new methodology is implemented on a 5 Bus system and the voltage profile is assessed. The
results are verified by a power flow algorithm [8]. The methodology is also implemented on the
14-Bus IEEE system.
Abstract 2:
The focus of this paper is to present an Artificial Neural Network based methodology to assess
the steady state security of a power system. The security of the system is assessed on the basis of
the voltage profile at each bus with reference to changes in generation and load in the system. The
input to the neural network is the voltage level at each bus. The ANN used is a feedforward
multilayer network trained with a backpropagation algorithm. The output of the ANN classifies
the security of the power system into Normal, Alert and Emergency states. An IEEE 14-Bus
system is considered to demonstrate the results of the methodology.
Speaker: Ramesh
Abstract: This presentation discusses the effects of three FACTS controllers: STATCOM, SSSC
and UPFC on voltage stability in power system. Accurate model of these controllers are used for
voltage stability studies. Continuation power flow is used to study the voltage stability in power
system. Saddle node bifurcation theory is used to determine location of these controllers in a
typical power system. From the results of voltage collapse studies using Power System Analysis
Toolbox (PSAT), the optimal location of these controllers are determined. The steady state
models of the controllers discussed and the techniques used for voltage stability studies are
applied to 6-bus power system and effects of the controllers on voltage collapse phenomena are
discussed.
Speaker: Ahlada
Abstract: This paper proposes a technique to identify critical double line outages and enhance
static security by optimal placement of FACTS devices using heuristics based GA. Two indices
have been used for contingency screening: double-line contingency index (DCI), based on line
overflows, and voltage sensitivity index (VSI), based on bus voltage violations. Contingency
screening is treated as the primary optimization problem with an objective of finding all doubleline outages with maximal DCI and VSI. Security enhancement is treated as a constrained
secondary optimization problem. The objective is to reduce transmission losses through the
branches of the system and reduce or remove the overflows and voltage violations present. The
voltage magnitude at each bus and the line flow through each branch for all the buses and
branches have been considered as inequality and equality constraints. The technique is
demonstrated using IEEE 14 bus and IEEE 30 bus systems.