Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645756
M. Salehifar, Ramin Salehi Arashloo, M. Moreno-Eguilaz, V. Sala, L. Romeral
In this paper, a new fault detection method based on signal normalization using a simple trigonometric function is presented and applied to a five phase converter for fault tolerant application under nonsinusoidal unbalanced current waveforms. Generality, simplicity, ability to localize faulty switch, multiple switch fault detection and robustness are achieved using this approach. Once theory is explained, simulation results with Matlab/Simulink and experimental waveforms are described to show the effectiveness of the proposed detection method. Experimenal results corroborate these simulation results.
{"title":"A simple and robust method for open switch fault detection in power converters","authors":"M. Salehifar, Ramin Salehi Arashloo, M. Moreno-Eguilaz, V. Sala, L. Romeral","doi":"10.1109/DEMPED.2013.6645756","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645756","url":null,"abstract":"In this paper, a new fault detection method based on signal normalization using a simple trigonometric function is presented and applied to a five phase converter for fault tolerant application under nonsinusoidal unbalanced current waveforms. Generality, simplicity, ability to localize faulty switch, multiple switch fault detection and robustness are achieved using this approach. Once theory is explained, simulation results with Matlab/Simulink and experimental waveforms are described to show the effectiveness of the proposed detection method. Experimenal results corroborate these simulation results.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"03 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127192859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645758
M. Bortolozzi, C. Bruzzese, F. Ferro, T. Mazzuca, M. Mezzarobba, G. Scala, A. Tessarolo, D. Zito
The reliability is a key requirement in electric actuators to be used for moving ship control surfaces. This paper addresses a fault-tolerant design for an innovative naval actuator based on an inverter-fed permanent magnet linear synchronous motor. Due to the highly non-conventional actuator concept, a detailed FEM modeling approach is presented in this paper for comparison of different design solutions. A fault tolerant modular stator structure is proposed. The modular winding can be designed based on an integer-slots or fractional-slots concept. The two solutions are compared in this paper, considering encumbrance and thrusting force performances. The linear motion can be reverted to rotary motion through a prismatic-rotoidal joint for coupling to on board ship steering gears used to drive control surfaces (rudders, stabilizing fins). A drive prototype has been built and is presently under testing to assess and refine the results of the FEM modeling presented in the paper.
{"title":"Magnetic optimization of a fault-tolerant linear permanent magnet modular actuator for shipboard applications","authors":"M. Bortolozzi, C. Bruzzese, F. Ferro, T. Mazzuca, M. Mezzarobba, G. Scala, A. Tessarolo, D. Zito","doi":"10.1109/DEMPED.2013.6645758","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645758","url":null,"abstract":"The reliability is a key requirement in electric actuators to be used for moving ship control surfaces. This paper addresses a fault-tolerant design for an innovative naval actuator based on an inverter-fed permanent magnet linear synchronous motor. Due to the highly non-conventional actuator concept, a detailed FEM modeling approach is presented in this paper for comparison of different design solutions. A fault tolerant modular stator structure is proposed. The modular winding can be designed based on an integer-slots or fractional-slots concept. The two solutions are compared in this paper, considering encumbrance and thrusting force performances. The linear motion can be reverted to rotary motion through a prismatic-rotoidal joint for coupling to on board ship steering gears used to drive control surfaces (rudders, stabilizing fins). A drive prototype has been built and is presently under testing to assess and refine the results of the FEM modeling presented in the paper.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"758 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116121485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645754
O. Magdun, S. Blatt, A. Binder
Transmission line models are commonly used to calculate and predict the voltage distributions along the inverter-fed electrical machine windings. In this paper, frequency-dependent parameters of the stator windings are calculated via finite element and analytical methods. They are implemented in a transmission line model to predict the voltage distribution in a round wire stator winding induction machine. As a difference from the existent models, the laminated iron core effects are taken into account by an eddy current loss resistance. A metal-oxide varistor model is implemented in the cable-machine winding simulation model, and the voltage distribution is calculated. Comparisons with the measurements are given.
{"title":"Calculation of stator winding parameters to predict the voltage distributions in inverter fed AC machines","authors":"O. Magdun, S. Blatt, A. Binder","doi":"10.1109/DEMPED.2013.6645754","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645754","url":null,"abstract":"Transmission line models are commonly used to calculate and predict the voltage distributions along the inverter-fed electrical machine windings. In this paper, frequency-dependent parameters of the stator windings are calculated via finite element and analytical methods. They are implemented in a transmission line model to predict the voltage distribution in a round wire stator winding induction machine. As a difference from the existent models, the laminated iron core effects are taken into account by an eddy current loss resistance. A metal-oxide varistor model is implemented in the cable-machine winding simulation model, and the voltage distribution is calculated. Comparisons with the measurements are given.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114783471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645753
O. Barambones
An adaptive sliding-mode position control for induction motors using the field oriented control theory is presented. The proposed sliding-mode control law incorporates an adaptive switching gain to avoid calculating an upper limit for the system uncertainties. The design also incorporates a sliding-mode flux estimator that operates on the principle of flux and current observer. The proposed observer uses a plant model and also includes a sliding mode terms to overcome the model uncertainties. The stability analysis of the proposed observer and controller under parameter uncertainties and load disturbances is provided using the Lyapunov stability theory. Finally experimental results show that the proposed controller with the proposed observer provides high-performance dynamic characteristics and that this control scheme is robust with respect to plant parameter variations and external load disturbances.
{"title":"An adaptive robust position control for induction machines using a sliding mode flux observer","authors":"O. Barambones","doi":"10.1109/DEMPED.2013.6645753","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645753","url":null,"abstract":"An adaptive sliding-mode position control for induction motors using the field oriented control theory is presented. The proposed sliding-mode control law incorporates an adaptive switching gain to avoid calculating an upper limit for the system uncertainties. The design also incorporates a sliding-mode flux estimator that operates on the principle of flux and current observer. The proposed observer uses a plant model and also includes a sliding mode terms to overcome the model uncertainties. The stability analysis of the proposed observer and controller under parameter uncertainties and load disturbances is provided using the Lyapunov stability theory. Finally experimental results show that the proposed controller with the proposed observer provides high-performance dynamic characteristics and that this control scheme is robust with respect to plant parameter variations and external load disturbances.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128028181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645720
O. Al-Naseem, M. El-Sayed
Variable frequency drives (VFD) are an integral part of many industrial plants and stations. Reliable operation and maintenance of these drives is vital to ensure sustained plant operation and availability. Understanding of the principles of operation of VFD systems as well as knowledge about their required operating environment is necessary for all operating personnel. Many times the operating personnel do not get involved with different technical issues until a complete failure has occurred. Hence, the awareness of the most dominant failure causes has a significant impact on assisting operators to avoid catastrophic failures and tremendous economic losses due to VFD shutdown. Proper plant design, accurate monitoring and data logging, following manufacturer preventive maintenance schedule, and choosing qualified team of operators can be the key to an efficient operation and a long lifetime for any VFD system. In this paper, we have analyzed the electrical and non-electrical causes of VFD failures based on a case study of a typical medium voltage VFD pumping station. Finally, recommendations are given from field analysis and observations.
{"title":"Analysis of electrical and non-electrical causes of variable frequency drive failures","authors":"O. Al-Naseem, M. El-Sayed","doi":"10.1109/DEMPED.2013.6645720","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645720","url":null,"abstract":"Variable frequency drives (VFD) are an integral part of many industrial plants and stations. Reliable operation and maintenance of these drives is vital to ensure sustained plant operation and availability. Understanding of the principles of operation of VFD systems as well as knowledge about their required operating environment is necessary for all operating personnel. Many times the operating personnel do not get involved with different technical issues until a complete failure has occurred. Hence, the awareness of the most dominant failure causes has a significant impact on assisting operators to avoid catastrophic failures and tremendous economic losses due to VFD shutdown. Proper plant design, accurate monitoring and data logging, following manufacturer preventive maintenance schedule, and choosing qualified team of operators can be the key to an efficient operation and a long lifetime for any VFD system. In this paper, we have analyzed the electrical and non-electrical causes of VFD failures based on a case study of a typical medium voltage VFD pumping station. Finally, recommendations are given from field analysis and observations.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"601 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132798826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645714
F. Blanquez, C. Platero, E. Rebollo, F. Blanquez
In this paper, the applicability of the FRA technique is discussed as a method for detecting inter-turn faults in stator windings. Firstly, this method is tested in an individual medium-voltage stator coil with satisfactory results. Secondly, the tests are extended to a medium-voltage induction motor stator winding, in which inter-turn faults are performed in every coil end of one phase. Results of the frequency response in case of inter-turn faults are evaluated in both cases for different fault resistance values. The experimental setup is also described for each experiment. The results of the application of this technique to the detection of inter-turn faults justify further research in optimizing this technique for preventive maintenance.
{"title":"Evaluation of the applicability of FRA for inter-turn fault detection in stator windings","authors":"F. Blanquez, C. Platero, E. Rebollo, F. Blanquez","doi":"10.1109/DEMPED.2013.6645714","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645714","url":null,"abstract":"In this paper, the applicability of the FRA technique is discussed as a method for detecting inter-turn faults in stator windings. Firstly, this method is tested in an individual medium-voltage stator coil with satisfactory results. Secondly, the tests are extended to a medium-voltage induction motor stator winding, in which inter-turn faults are performed in every coil end of one phase. Results of the frequency response in case of inter-turn faults are evaluated in both cases for different fault resistance values. The experimental setup is also described for each experiment. The results of the application of this technique to the detection of inter-turn faults justify further research in optimizing this technique for preventive maintenance.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131635316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645717
M. Orman, A. Nowak, J. Ottewill, C. Pinto
This paper presents a newly developed algorithm for evaluating the health of an induction machine. The proposed algorithm is based on spectrum analysis of an impedance calculated using measured stator current and voltage signals. The main idea is to calculate the frequency spectrum of the impedance for each power phase and compare specific differences between phases. Experimental investigations show that the method yields very accurate results and can form an important part of a machine monitoring system. In particular the presented method is shown to be successful in detecting missing wedges in electric motors.
{"title":"A novel non-invasive method for detecting missing wedges in an induction machine","authors":"M. Orman, A. Nowak, J. Ottewill, C. Pinto","doi":"10.1109/DEMPED.2013.6645717","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645717","url":null,"abstract":"This paper presents a newly developed algorithm for evaluating the health of an induction machine. The proposed algorithm is based on spectrum analysis of an impedance calculated using measured stator current and voltage signals. The main idea is to calculate the frequency spectrum of the impedance for each power phase and compare specific differences between phases. Experimental investigations show that the method yields very accurate results and can form an important part of a machine monitoring system. In particular the presented method is shown to be successful in detecting missing wedges in electric motors.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116295258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645747
K. Gyftakis, D. Athanasopoulos, J. Kappatou
The diagnosis of faults in induction motors is a crucial scientific subject since it affects the industrial production functionality and reliability. Lately, a new scientific area is born: the electrical machines prognostics. So, aiming to this direction the complete knowledge of all abnormal parameters during the induction motor operation should be identified. In this paper, a methodology is described in order to identify not only if there is a broken bar fault, but also if the induction motor voltage supply is asymmetrical at the same time. The investigation is carried out with transient FEM simulations. The proposed methodology comes to supplement the traditional MCSA method with desired satisfaction.
{"title":"Broken bar fault diagnosis in single and double cage induction motors fed by asymmetrical voltage supply","authors":"K. Gyftakis, D. Athanasopoulos, J. Kappatou","doi":"10.1109/DEMPED.2013.6645747","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645747","url":null,"abstract":"The diagnosis of faults in induction motors is a crucial scientific subject since it affects the industrial production functionality and reliability. Lately, a new scientific area is born: the electrical machines prognostics. So, aiming to this direction the complete knowledge of all abnormal parameters during the induction motor operation should be identified. In this paper, a methodology is described in order to identify not only if there is a broken bar fault, but also if the induction motor voltage supply is asymmetrical at the same time. The investigation is carried out with transient FEM simulations. The proposed methodology comes to supplement the traditional MCSA method with desired satisfaction.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129750780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645774
A. Soualhi, G. Clerc, H. Razik, F. Rivas
Rolling element bearings are devices used in almost every electrical machine. Therefore, it is important to monitor and track the degradation of bearings. This paper presents a new approach to predict the degradation of bearings by a time series forecasting model called the neo-fuzzy neuron. The proposed approach uses the root mean square extracted from vibration signals as a health indicator. The root mean square is used here as an input of the neo-fuzzy neuron in order to estimate the evolution of bearing's degradation in time. Experimental degradation data provided by the University of Cincinnati is used to validate the proposed approach. A comparative study between the neo-fuzzy neuron and the adaptive neuro-fuzzy inference system is carried out to appraise their prediction capabilities. The experimental results show that the neo-fuzzy model can track the degradation of bearings.
{"title":"Long-term prediction of bearing condition by the neo-fuzzy neuron","authors":"A. Soualhi, G. Clerc, H. Razik, F. Rivas","doi":"10.1109/DEMPED.2013.6645774","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645774","url":null,"abstract":"Rolling element bearings are devices used in almost every electrical machine. Therefore, it is important to monitor and track the degradation of bearings. This paper presents a new approach to predict the degradation of bearings by a time series forecasting model called the neo-fuzzy neuron. The proposed approach uses the root mean square extracted from vibration signals as a health indicator. The root mean square is used here as an input of the neo-fuzzy neuron in order to estimate the evolution of bearing's degradation in time. Experimental degradation data provided by the University of Cincinnati is used to validate the proposed approach. A comparative study between the neo-fuzzy neuron and the adaptive neuro-fuzzy inference system is carried out to appraise their prediction capabilities. The experimental results show that the neo-fuzzy model can track the degradation of bearings.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128554002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-24DOI: 10.1109/DEMPED.2013.6645731
Y. Maouche, Abdelfettah Boussaid, M. Boucherma, A. Khezzar
In literature, open phase faults in multi-phase induction motor have been investigated. However rotor faults and their impact on the performance of multi-phase induction motor aren't widely discussed. An analytical study of the pulsating torque and harmonic components in rotor current of six-phase induction machine as a function of displacement between sub-windings in healthy and faulty cases (the rotor broken bar) is developed. The novel formula of pulsation torques of six-phase induction motor presented in this paper can be used as a fault indicator for broken rotor bars. The used model is based on multiple coupled circuits and takes into account the geometry and winding layout, including the calculation of pulsating torques. The simulation results show the disappearance of some higher rotor slot harmonics in torque spectrums as well as a significant improvement in the rotor current harmonics for a specific displacement between sub-windings.
{"title":"Analytical study of pulsating torque and harmonic components in rotor current of six-phase induction motor under healthy and faulty conditions","authors":"Y. Maouche, Abdelfettah Boussaid, M. Boucherma, A. Khezzar","doi":"10.1109/DEMPED.2013.6645731","DOIUrl":"https://doi.org/10.1109/DEMPED.2013.6645731","url":null,"abstract":"In literature, open phase faults in multi-phase induction motor have been investigated. However rotor faults and their impact on the performance of multi-phase induction motor aren't widely discussed. An analytical study of the pulsating torque and harmonic components in rotor current of six-phase induction machine as a function of displacement between sub-windings in healthy and faulty cases (the rotor broken bar) is developed. The novel formula of pulsation torques of six-phase induction motor presented in this paper can be used as a fault indicator for broken rotor bars. The used model is based on multiple coupled circuits and takes into account the geometry and winding layout, including the calculation of pulsating torques. The simulation results show the disappearance of some higher rotor slot harmonics in torque spectrums as well as a significant improvement in the rotor current harmonics for a specific displacement between sub-windings.","PeriodicalId":425644,"journal":{"name":"2013 9th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics and Drives (SDEMPED)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128912011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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