Application of structure preserving energy margin sensitivity to determine the effectiveness of shunt and series FACTS devices

Abstract

Abstract-This paper presents a structure preserving energy margin sensitivity based analysis to determine the effectiveness of FACTS devices to improve transient stability of a power system. A structure preserving energy model, which retains the topology of the network is used to derive simple analytical expressions for improvement in energy margin due to series or shunt compensation. The expressions are in terms of current magnitude through a line for series compensation and voltage magnitude at a bus for shunt compensation. Therefore, these expressions are easy to interpret in the context of applying compensation at strategic locations.The proposed method is applied to a four-machine, ten-bus system and a ten-machine, 39-bus New England system, and its validity is demonstrated through time domain simulations both for classical and detailed model with AVR for generators.Index Terms-Energy margin, FACTS devices, power system transient stability, structure preserving energy function.

Determination of Effectiveness of Transient Stability Controls Using Reduced Number of Trajectory Sensitivity Computations

“…For a lossless classical model of power system with constant real power loads, where the states are the normalized (i.e., scaled by the ) rotor angle and speeds, it is shown in the Appendix that (8) where and and are the input and output matrices, respectively, for a specific choice of and (see Table I). is an identity matrix of size and is the number of generators.…”

“…Similarly, sensitivity analysis of EM with respect to generation shifts, network changes and load changes, proposed in [7] form a basis for making necessary changes in the post fault system to improve the transient behavior of a system. Sensitivity of structure preserving energy margin to line reactance and shunt susceptance has been used in [8] to determine the effectiveness of series and shunt compensation at different locations in a power system.…”

A Comprehensive Survey of Optimal Placement and Coordinated Control Techniques of FACTS Controllers in Multi-Machine Power System Environments

“…An index based approach known as a Location Index for Effective Damping (LIED) method has been proposed for identifying the location of SVC and a Variable Series Capacitor (VSrC) in large-scale power systems for damping effectively in [16]. A structure preserving energy margin sensitivity based analysis has been addressed for determine the effectiveness of FACTS devices to improve transient stability of a power system in [17]. A controllability index method has been proposed for select the input signals for both single and multiple FACTS devices in small and large power systems for damping inter-area oscillations in [18].…”

Suitable placements of multiple FACTS devices to improve the transient stability using trajectory sensitivity analysis

“…It is clear that the initial value for the trajectory sensitivities of dynamic states is an identity matrix. Using this identity matrix, the initial values for the trajectory sensitivities of algebraic states can be also computed from (6).…”

“…The significant advantage of this method is its capability to provide a stability index [1]. Several methodologies have been proposed based on the sensitivity of TEF to determine the effectiveness of FACTS devices to improve system's transient stability, see [5], and [6]. Despite all the advantages of the TEF based methods, the main shortcoming of them is their high complexity in the following situations: (i) considering differential-algebraic equation (DAE) models of power systems, (ii) dealing with the detailed models of the system's components, (iii) when a number of system's parameters have to be taken into account for the sensitivity analysis [7].…”