A Wavelet-Based Approach to FRF Identification From Incomplete Data

Frequency response function (FRF) estimation from measured data is an essential step in the design, control, and analysis of complex dynamical systems, including thermal and motion systems. Especially for systems that require long measurement time, missing samples in the data record, e.g., due to measurement interruptions, often occur. The...

Closed-Loop Frequency Analysis of Reset Control Systems

This article introduces a closed-loop frequency analysis tool for reset control systems. To begin with sufficient conditions for the existence of the steady-state response for a closed-loop system with a reset element and driven by periodic references are provided. It is then shown that, under specific conditions, such a steady-state response...

Comprehensive Study on Transformer Fault Detection via Frequency Response Analysis

The sudden outage of a transformer due to a fault can cause irreparable damage to the electricity industry. Hence, by conducting momentarily inspections of the transformer's condition, faults can be promptly detected, and the transformer can be disconnected from the power grid to prevent subsequent failures in this equipment. Detecting faults...

Cyber-Physical Testbed Co-simulation Real-Time: Normal and Abnormal System Frequency Response

Future carbon-neutral power systems impose many challenges; one is the urgent need for a simulation platform that allows replicating the complex systems’ actual dynamic performance. This paper shows the results of implementing a cyber-physical testbed co-simulation in real-time to analyse the system frequency response considering primary...

System Parameter Identification of Thermal Generation Unit in the Mongolian Electrical Grid: Real-Life Frequency Response Test

Mongolian power grid (MPG) is becoming more eco-friendly as the power system is continuously integrating renewable energy, which reached 20% of the total installed capacity of Mongolia in 2020. The daily operation and the safety of the MPG have become very challenging because of increased levels of energy in the system. Therefore, the dynamic...

Human Threshold Model for Perceiving Changes in System Dynamics

Limitations of a haptic device can cause distortions of the force feedback it presents. Just-noticeable difference (JND) in system dynamics is important for creating transparent haptic interaction. Based on the previous work, this article presents a unified model that extends the existing JND rule. Our approach projects the JNDs in the...

Efficient limitation of resonant peaks by topology optimization including modal truncation augmentation

In many engineering applications, the dynamic frequency response of systems is of high importance. In this paper, we focus on limiting the extreme values in frequency response functions, which occur at the eigenfrequencies of the system, better known as resonant peaks. Within an optimization, merely sampling the frequency range and limiting the...

Autoregressive moving average graph filter design

In graph signal processing, signals are processed by explicitly taking into account their underlying structure, which is generally characterized by a graph. In this field, graph filters play a major role to process such signals in the so-called graph frequency domain. In this paper, we focus on the design of autoregressive moving average ...

Response of large-scale coastal basins to wind forcing: Influence of topography

Because wind is one of the main forcings in storm surge, we present an idealised process-based model to study the influence of topographic variations on the frequency response of large-scale coastal basins subject to time-periodic wind forcing. Coastal basins are represented by a semi-enclosed rectangular inner region forced by wind. It is...

The deterministic power-spectral-density-method for linear systems

The Deterministic Power-Spectral-Density-method has been derived directly from the continuous P.S.D.-method. It can be regarded as a "translation" from the frequency domain to the space or time domain. The critical gust profile, giving maximum response, is obtained directly. The D.P.S.D.-method gives the same results as the continuous P.S.D.-...

Frequency response analysis of hybrid systems

Current design methods for digital control systems to be operated in a continuous environment do not always result in the most efficient use of digital computing hardware. To improve this situation, a dedicated frequency response analysis method was developed for hybrid systems. For practical use of the method, it has been expanded to an...