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A data-driven methodology is considered in this paper focusing towards the Remaining Useful Life (RUL) prediction. Firstly, diagnostic features are extracted from training data and an analytical function that best approximates the... more
A data-driven methodology is considered in this paper focusing towards the Remaining Useful Life (RUL) prediction. Firstly, diagnostic features are extracted from training data and an analytical function that best approximates the evolution of the fault is determined and used to learn the parameters of an Unscented Kalman Filter (UKF). UKF is based on the recursive estimation of the Classic Kalman Filter (CKF) and the Unscented Transform, presenting advantages over the Extended Kalman Filter (EKF) for high non-linear systems. The learned UKF is further applied on testing data in order to predict the RUL under different operating conditions. The influence of the starting point of the prediction is analyzed and a method for the automated parameter tuning of the Kalman Filter is considered. In the end, the result is evaluated and compared to CKF and EKF on experimental data based on dedicated performance metrics.
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Research Interests: Computer Science and IEEE
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In this study, noise and vibration measurements were carried out on a multi-phase 12/8 switched reluctance (SR) motor and analyzed with vibro-acoustic techniques. When evaluating the behavior of electric powertrains for automotive... more
In this study, noise and vibration measurements were carried out on a multi-phase 12/8 switched reluctance (SR) motor and analyzed with vibro-acoustic techniques. When evaluating the behavior of electric powertrains for automotive applications, it is necessary to perform a vibro-acoustic analysis, particularly in view of the acoustic comfort perceived by the driver and passengers. High frequency tonal noise can be very annoying and even causes long term damage. Therefore, the noise and vibrations must be deliberately optimized. In case of a SR motor, the radial magnetic forces between the stator and rotor are the main excitation source, yielding large deformations of the stator housing and emissions of noise. Measurements and simulation results are compared for different load conditions. The dominant vibration modes are analyzed with modal analysis techniques. The unpleasant tonal noise of the motor is objectively quantified by noise metrics. Finally, the relationship between the cu...
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Switched reluctance machines (SRMs) benefit from major advantages, such as cheap and robust construction and electrical fault tolerance, but also suffer from noise, vibration and harshness (NVH) issues. The present paper focuses on the... more
Switched reluctance machines (SRMs) benefit from major advantages, such as cheap and robust construction and electrical fault tolerance, but also suffer from noise, vibration and harshness (NVH) issues. The present paper focuses on the NVH influence of the current hysteresis controller, which is generally used in SRM drives. The impact of changes in the controller sampling time is experimentally investigated on an 8/6 15 kW (30 kW peak) SRM. In practice the initial hysteresis controller, implemented on a dSPACE platform running at 10 kHz, is compared with an improved version running twenty times faster on external microcontrollers. Tests are performed in the form of run-ups, in order to study the drive in transient conditions and investigate a continuous speed range, while vibration, current and sound pressure waves are measured. Current waveforms are also simulated using AMESim software to compare with experimental measurements. Both controller implementations are modelled and both...
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The development of power converters has permitted the rise of switched reluctance machines(SRMs), due to their simple and cheap design and of their inherent fault tolerance. However,those machines suffer from torque ripple and noise and... more
The development of power converters has permitted the rise of switched reluctance machines(SRMs), due to their simple and cheap design and of their inherent fault tolerance. However,those machines suffer from torque ripple and noise and vibration issues, which constitute an obstacleto the extension of their application domain. This paper presents the influence of thebandwidth of a current-hysteresis controller on an 8/6 SRM in terms of noise, vibration andharshness. Simulations in AMESim environment and measurements on a 15 kW test bench areperformed in transient state, based on continuous variation of the hysteresis bandwidth. Phasecurrents, acoustic noise and radial vibrations are measured without and with load, allowing forcomparison of hysteresis-band-frequency plots. This transient state approach enables showingthe evolution of a part of the frequency components with hysteresis bandwidth and distinguishingthem from other components linked to speed or to structural behaviour of ...
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EUROPEAN COMMISSION Horizon 2020 GV-07-2017 GA # 769506 Deliverable No. OBELICS D1.2 Deliverable Title Reference use cases, requirements and metrics for battery design & testing Deliverable Date 2018-06-30 Deliverable Type REPORT... more
EUROPEAN COMMISSION Horizon 2020 GV-07-2017 GA # 769506 Deliverable No. OBELICS D1.2 Deliverable Title Reference use cases, requirements and metrics for battery design & testing Deliverable Date 2018-06-30 Deliverable Type REPORT Dissemination level Confidential Written By Benjamin Zillman (Bosch) Jürgen Nuffer (LBF) Vincent Heiries (CEA) Ngoc Anh Nguyen (AVL) Vishwasri Ramaka (AVL) Werner Bergmayr (AVL) 2018-08-17
Rolling bearings are an important component in rotating machinery and their failure is one of the main causes of machine breakdown. It has been proven that diagnosis methods based on envelope analysis of vibration signals enable the... more
Rolling bearings are an important component in rotating machinery and their failure is one of the main causes of machine breakdown. It has been proven that diagnosis methods based on envelope analysis of vibration signals enable the detection of bearing faults in medium to high speed regimes. However, it has been observed that these methods do not provide a satisfactory performance for diagnosing bearings at low rotational speed. One of the known reasons for this is the usage of inadequate monitoring techniques and measuring instruments that are not sensitive enough to low frequency signature. A major challenge for fault diagnosis at low rotational speeds is their slow evolution in time and the weak amplitude of the induced-fault vibrations. This paper aims at presenting the techniques proposed by Randall and co-workers that allow semi-automated processing of machine vibration signals to diagnose bearing faults under different operational conditions for low and medium rotational spe...
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This paper presents the performances of a surface-mounted permanent-magnet synchronous machine (SM-PMSM) from the electromagnetic and structural analysis point of view, which are evaluated numerically and through tests. The goal is to... more
This paper presents the performances of a surface-mounted permanent-magnet synchronous machine (SM-PMSM) from the electromagnetic and structural analysis point of view, which are evaluated numerically and through tests. The goal is to evaluate the possibility to use this SM-PMSM for the propulsion of a light-electric vehicle (L-EV), knowing that on one hand it has the best power density and, on the other hand, a torque wave with high ripples induces vibration and noise. This paper discusses the limits and the advantages for such a propulsion solution in order to evaluate its suitability for the L-EV applications.
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The paper discusses the advanced spectral analysis performed on two important classes of electric drive systems, namely Switched Reluctance Motors (SRM) and Permanent Magnet Synchronous Machines (PMSM). In particular, the noise and... more
The paper discusses the advanced spectral analysis performed on two important classes of electric drive systems, namely Switched Reluctance Motors (SRM) and Permanent Magnet Synchronous Machines (PMSM). In particular, the noise and vibration signatures as a function of operating speed are analyzed by using a waterfall analysis and an order analysis. The harmonic and modulation components attributable to the motor configuration, the motor operating principles and the Variable Speed Drives (VSD) are identified in two cases for each motor type. Furthermore, a number of approaches to improve the noise and vibration performance have been evaluated, in particular by acting on the controls of the variable speed drive. Some comments on additional noise source phenomena such as caused by phase unbalance are given.
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The purpose of the paper is to present the summary of results related to the characterization of the motorization of a light electric vehicle (L-EV). This analysis is made based on both a numerical approach, by using the electromagnetic... more
The purpose of the paper is to present the summary of results related to the characterization of the motorization of a light electric vehicle (L-EV). This analysis is made based on both a numerical approach, by using the electromagnetic as well as structural dynamics finite element method (FEM), and an experimental approach evaluating the noise, vibration and harshness (NVH) behavior.
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This paper presents a comparison of soft and hard chopping on an 8/6 SRM in terms of noise, vibration and harshness. Transient-state measurements are used to plot speedfrequency signatures of current, vibration and acoustic noise of the... more
This paper presents a comparison of soft and hard
chopping on an 8/6 SRM in terms of noise, vibration and
harshness. Transient-state measurements are used to plot speedfrequency
signatures of current, vibration and acoustic noise of
the SRM for different load torques. With this technique speedrelated
frequencies can be distinguished from resonance
frequencies, and therefore, more information can be extracted
from the plots. The results show that hard chopping increases the
loudness of acoustic noise compared to soft chopping, with a
frequency shift to higher values. This however leads to an
attenuation of the vibration and noise amplitudes at the most
critical resonance of the SRM, situated at a relatively low
frequency.
chopping on an 8/6 SRM in terms of noise, vibration and
harshness. Transient-state measurements are used to plot speedfrequency
signatures of current, vibration and acoustic noise of
the SRM for different load torques. With this technique speedrelated
frequencies can be distinguished from resonance
frequencies, and therefore, more information can be extracted
from the plots. The results show that hard chopping increases the
loudness of acoustic noise compared to soft chopping, with a
frequency shift to higher values. This however leads to an
attenuation of the vibration and noise amplitudes at the most
critical resonance of the SRM, situated at a relatively low
frequency.