Power System Oscillation Damping Using New Facts Device

This paper presents about improving stability of the system which can be possible with new FACTS device with more convenient. FACTS devices come under the influence of power electronics equipment. Distributed Power Flow Controller is a FACTS device used for damping low frequency oscillation with new controlling approach. It is valid for a wide range of the operating condition. In this work explain the basic model and its steady state operation, mathematical analysis injection of current control model of the DPFC. Using damping controller used in DPFC facts device as input to implement the task of power oscillation damping .Here this work had a brief study on damping, terminal voltage and excitation voltage at different load conditions, simulation results demonstrate damping low frequency oscillation at nominal, light and heavy loading condition

Modeling and Control of Wind Turbine to Damp the Power Oscillation

Damping inter-area oscillation by using a permanent magnet synchronous generator (PMSG) wind turbine is considered. The PMSG wind turbine is connected to the IEEE-30 bus power system at different buses. H-infinity design controller is proposed to modulate the power where the input of the H-infinity control is the variation of the local grid generator speed and the output is feedback to activate the PMSG speed control, blade pitch angle control and dc voltage control. MATLAB/SIMULINK is used in this study. The IEEE-30 bus system is reduced to 7 buses based on the number of generators to simplify the stability study. The method is applied to a seven-area power system that exhibits undamped oscillations. Results presented in this study demonstrate the effectiveness of the wind generator in increasing system damping considerably

Damping low-frequency oscillations in power systems using grid-forming converters

The increasing incorporation of renewable energy in power systems is causing growing concern about system stability. Renewable energy sources are connected to the grid through power electronic converters, reducing system inertia as they displace synchronous generators. New grid-forming converters can emulate the behavior of synchronous generators in terms of inertia provision and other grid services, like power-frequency and voltage-reactive regulation. Nevertheless, as a consequence of synchronous generator emulation, grid-forming converters also present angle oscillations following a grid disturbance. This paper proposes two novel power stabilizers for damping low-frequency oscillations (LFOs) in the power system. The first power stabilizer provides power oscillation damping through active power (POD-P), and it is implemented in a grid-forming converter, using the active power synchronization loop to damp system oscillations by acting on the converter angle. The second one provides power oscillation damping through reactive power (POD-Q), and it is implemented in a STATCOM, using the voltage control loop to damp system oscillations. Both proposals are first assessed in a small-signal stability study and then in a comprehensive simulation. Moreover, two cases are considered: damping the oscillations of a single machine connected to an infinite bus through a tie-line, and damping the inter-area oscillations in a two-area system. Simulation results, as well as the stability study, demonstrate the ability of both stabilizers to damp power system oscillations, being the POD-P more effective than the POD-Q, but at the cost of requiring some kind of energy provision at the DC bus.This work was supported by the Spanish Research Agency under Project PID2019-106028RB-I00/ AEI/10.13039/501100011033

Data-Driven Diagnostics of Mechanism and Source of Sustained Oscillations

Sustained oscillations observed in power systems can damage equipment, degrade the power quality and increase the risks of cascading blackouts. There are several mechanisms that can give rise to oscillations, each requiring different countermeasure to suppress or eliminate the oscillation. This work develops mathematical framework for analysis of sustained oscillations and identifies statistical signatures of each mechanism, based on which a novel oscillation diagnosis method is developed via real-time processing of phasor measurement units (PMUs) data. Case studies show that the proposed method can accurately identify the exact mechanism for sustained oscillation, and meanwhile provide insightful information to locate the oscillation sources.Comment: The paper has been accepted by IEEE Transactions on Power System

Role of fluctuations and nonlinearities on field emission nanomechanical self-oscillators

A theoretical and experimental description of the threshold, amplitude, and stability of a self-oscillating nanowire in a field emission configuration is presented. Two thresholds for the onset of self-oscillation are identified, one induced by fluctuations of the electromagnetic environment and a second revealed by these fluctuations by measuring the probability density function of the current. The ac and dc components of the current and the phase stability are quantified. An ac to dc ratio above 100% and an Allan deviation of 1.3x10-5 at room temperature can be attained. Finally, it is shown that a simple nonlinear model cannot describe the equilibrium effective potential in the self-oscillating regime due to the high amplitude of oscillations

Enhanced power system stability by coordinated PSS design [Correction]

A step-by-step coordinated design procedure for PSSs and AVRs in a strongly-coupled system is described. It is shown that it is possible to separate the design of individual PSSs and to separate the design of individual AVRs. Thereby, the designs of AVR and PSS devices at a given machine can be coordinated to achieve near optimal overall power system stability performance, including oscillation stability performance and transient stability performance. The proposed coordinated PSS/AVR design procedure is established within a frequency domain framework and serves as a most useful small-signal complement to established large-signal transient simulation studies

Improving long line stability by integrating renewables using static synchronous generators

Postprint (author's final draft