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A multi-channel real-time sound pressure spectrum analyzer was demonstrated for investigating abnormal noises of tapered roller bearings (TRBs). The sound sensing system was developed to replace the existing quality-control method conducted by human ears. All data collected by proto-type were performed by using data processing module. The background was identified at a low frequency band. Peaks at...
Gas Insulated Switchgear (GIS) has been in use in transmission system for more than 30 years with good reliability. However, in our case study of 631 CB-bays of GIS operating under tropical conditions, we observed failure rates over twice the value reported in the 3rd CIGRE's survey of 2007. Following this observation, it becomes practically important to develop a condition assessment model for GIS...
Emergency protection of objects in the process of testing and functioning should respond to a wide range of abnormal situations: malfunctions, which can be eliminated during testing; emergency situations that can be eliminated in the operational mode, or require the shutdown of the process and the elimination of the consequences of the accident; catastrophic situations that require an a priori reaction...
This work is part of the monitoring and diagnosis of defects of the squirrel cage asynchronous machine, in particular the defect of rotor bar breaks. The design of a system for monitoring, detecting and locating faults from births for different loads of the machine is achieved by the use of advanced intelligent techniques based on neural networks; ANFIS-based neuro-fuzzy network whose knowledge base...
In the paper, principles of constructing systems of information support of human-operators (IOSS) of power units of nuclear power plants (NPP) and their place within the system of upper unit-level of automated process control systems (APCS) of NPP. The purpose of implementation of the NPP IOSS is preventing or decreasing the frequency and heaviness of operator errors appearing under transients and...
In case of the decision of the task of design of automated control systems for crucial objects, a minimum possible level of risks at uncontrollable interference in the processes of functioning of these systems, and also minimization of negative consequences from a similar interference in the course of its operation are required. In connection with this, on the basis of the system theory of conflict...
The safety problem is an important factor restricting the development of electric vehicles which caused by many kinds of faults in the power battery pack. How to diagnose the multiple faults in the battery pack becomes the focus and difficulty. This paper proposes a multi-fault detection method for battery management systems. Instead of measuring the voltage of individual cells, an interleaved connected...
Cough sound analysis has attracted interest as a potential low-cost diagnostic tool for low-resource settings, where the burden of pulmonary disease is quite high. However, published results on cough sound analysis are generally limited to specific pulmonary diseases (e.g. detection of Whooping cough — Pertussis) and the study sizes are small. In this paper, we present a general framework for cough...
In this work, we set the foundations for the design of a control system based on the measurement of flame's total radiation from a combustion process. The key aspect of this approach is that flame radiation from the combustion process can be successfully modeled by means of a Hammerstein system. The static nonlinearity, present in the examples studied by the authors, proves to be mild and measurable...
Operation and condition of fluid handling systems can be monitored with soft sensors applying variablespeed drive estimates. This paper studies the use possibilities of modern variable-speed drives in the remote diagnostics of pump and fan systems. Paper also introduces cases, where system maintenance need could be determined with the variable-speed drive.
The paper presents results of a research study on the nature of energy flow of an axial flux signal of an induction motor between two adjacent frequency bandwidths in steady-state and depending on the machine load. Existing periodic energy flows of this diagnostic hamper both fault or damage detection and identification. To ensure a sufficient resolution of diagnostic systems it is required to separate...
The paper presents the possibility of using a two-dimensional field-circuit model of a squirrel cage induction motor for qualitative tests of the axial leakage flux course used in non-invasive diagnostics of induction machines. The study considered the reduction of leakage fluxes associated with the stator and rotor winding to the zero component of the symmetric components system. A qualitative comparison...
This paper will describe recent developments in the practical application of multivariate Statistical Process Control (SPC) techniques to improve and automate anomaly detection in complex systems as part of a comprehensive Condition Based Maintenance (CBM) system. The CBM implementation process will be broken down into phases from planning to operation. The operational CBM system includes data acquisition,...
In the paper a thermal method for diagnostics the state of the aircraft external contour in flight is proposed. Results of the computer simulation and wind tunnel experiment on the possibility of detecting the moment, place, extent and type of damage to the condition of the aircraft external contour in flight are presented and analyzed. On the basis of the research results and proposed structural...
The description of the main steps of the method for determining the coordinates of the extrema of periodic signals is given. This method is based on multi-start optimization using the wavelet transform. Such an approach makes it possible to increase noise resistance and reduce sensitivity to local extrema of periodic signals. The evaluation of the possibilities of this method was carried out by determining...
This article is devoted to the actual problem of medical equipment — the creation of a portable analyzer for monitoring blood biochemical parameters: glucose and cholesterol. A correlation analysis of the concentration of glucose and cholesterol in the blood with the parameters of arterial pressure (BP) and excess body mass index (BMI) was carried out using computer simulation. Imitative models are...
This paper describes a novel technique for creating the test program sets (TPSs) that are used by automatic test equipment (ATE) to test electronic circuits and devices. This paper presents an architecture consisting of a genetic algorithm (GA) test proposer and a pattern classifier test evaluator. This architecture has been shown to produce optimized test sequences without human intervention. In...
Vibrations of high speed SRM design focused on possible highest efficiency and low torque ripples both in motoring and generating mode of operation are investigated. The main constructional nodes that are source of vibrations are identified based on comparison of time sequences of motor frame displacement acceleration with total and phase motor current. Vibration analysis is the second stage of design...
This paper discusses the stator winding interturn short fault detection for three phase Permanent Magnet Synchronous Machines (PMSMs). The implementation of the Extended Kalman filter (EKF)-based fault detection algorithm is discussed. The implemented algorithm was verified with the emulated fault during different operating conditions of the drive. Measurements on a real PMSM and the implementation...
The authors of this paper suggest a mathematical model of a vessel diesel-generator installation meeting in larger extent the specific properties of such system and its application. A distinctive feature of the method under consideration is the use of the synchronous generator itself as a precise multifunctional sensor of the diagnostic information. The paper is also presenting the results of practical...
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