Pub Date : 2015-05-10DOI: 10.1109/IEMDC.2015.7409252
Negin Lashkari, Hamid Fekri Azgomi, J. Poshtan, M. Poshtan
Detection of stator faults in their early stage is of great importance since they propagate rapidly and may cause further damage to the motor. Some variations in induction motors such as torque load anomalies must be considered in order to reliably detect stator faults. This paper presents robust artificial intelligence (AI) techniques for interturn short circuit (ITSC) fault detection of stator in three phase induction motors. In this work, the focus is first on the application of artificial neural networks and then fuzzy logic systems to reduce significantly the effect of load variations on fault detection procedure. The proposed ANN methodology has the merit to detect and locate ITSC fault, while the Fuzzy approach is capable of detecting and diagnosing the severity of ITSC fault. The simulation and experimental results are also given to verify the efficiency of both approaches under ITSC fault and load change.
{"title":"Robust stator fault detection under load variation in induction motors using AI techniques","authors":"Negin Lashkari, Hamid Fekri Azgomi, J. Poshtan, M. Poshtan","doi":"10.1109/IEMDC.2015.7409252","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409252","url":null,"abstract":"Detection of stator faults in their early stage is of great importance since they propagate rapidly and may cause further damage to the motor. Some variations in induction motors such as torque load anomalies must be considered in order to reliably detect stator faults. This paper presents robust artificial intelligence (AI) techniques for interturn short circuit (ITSC) fault detection of stator in three phase induction motors. In this work, the focus is first on the application of artificial neural networks and then fuzzy logic systems to reduce significantly the effect of load variations on fault detection procedure. The proposed ANN methodology has the merit to detect and locate ITSC fault, while the Fuzzy approach is capable of detecting and diagnosing the severity of ITSC fault. The simulation and experimental results are also given to verify the efficiency of both approaches under ITSC fault and load change.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"154 1","pages":"1446-1451"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79877838","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409059
P. Reddy, Kevin Grace, A. El-Refaie
Synchronous reluctance machines are very appealing for high speed traction motor design due to their robustness, simple structure, absence of magnets, and simple control. The absence of magnets means that synchronous reluctance machines are not susceptible to price variability and sustainability of rare-earth materials. Also, there are no concerns about demagnetization or uncontrolled generation mode. However, the challenge of achieving a good constant power to speed ratio is dependent on the mechanical aspects of the design. Conventional synchronous reluctance designs perform poorly compared to the permanent magnet machines due the presence of bridges and/or center posts in absence of the magnets to help saturate these regions. In this case, the challenge of rotor mechanical retention is addressed with the help of a sleeve on the rotor to reduce the need for bridges and/or center posts. Design optimization including the mechanical aspects of the sleeve is presented in this paper. The final design with a sleeve will be shown to be superior to a conventional design in terms of power density, rotor losses, saliency and torque ripple.
{"title":"Conceptual design of sleeve rotor synchronous reluctance motor for traction applications","authors":"P. Reddy, Kevin Grace, A. El-Refaie","doi":"10.1109/IEMDC.2015.7409059","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409059","url":null,"abstract":"Synchronous reluctance machines are very appealing for high speed traction motor design due to their robustness, simple structure, absence of magnets, and simple control. The absence of magnets means that synchronous reluctance machines are not susceptible to price variability and sustainability of rare-earth materials. Also, there are no concerns about demagnetization or uncontrolled generation mode. However, the challenge of achieving a good constant power to speed ratio is dependent on the mechanical aspects of the design. Conventional synchronous reluctance designs perform poorly compared to the permanent magnet machines due the presence of bridges and/or center posts in absence of the magnets to help saturate these regions. In this case, the challenge of rotor mechanical retention is addressed with the help of a sleeve on the rotor to reduce the need for bridges and/or center posts. Design optimization including the mechanical aspects of the sleeve is presented in this paper. The final design with a sleeve will be shown to be superior to a conventional design in terms of power density, rotor losses, saliency and torque ripple.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"25 1","pages":"195-201"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81744966","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409083
A. El-Refaie
Over the past 2-3 decades there is has been several attempts to bring power electronics/drives closer and more tightly integrated with electrical machines. Such activities intensified over the past several years. The drivers for this are technology breakthroughs in power electronic devices, new materials as well as the increasingly system requirements for a wide range of applications. This paper will provide a thorough survey of both commercial products as well as what is available in literature in terms of integrated electrical machines and drives. The paper will cover a wide range of applications highlighting the advantages and challenges of achieving such integration. The paper will also highlight the current research trends.
{"title":"Integrated electrical machines and drives: An overview","authors":"A. El-Refaie","doi":"10.1109/IEMDC.2015.7409083","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409083","url":null,"abstract":"Over the past 2-3 decades there is has been several attempts to bring power electronics/drives closer and more tightly integrated with electrical machines. Such activities intensified over the past several years. The drivers for this are technology breakthroughs in power electronic devices, new materials as well as the increasingly system requirements for a wide range of applications. This paper will provide a thorough survey of both commercial products as well as what is available in literature in terms of integrated electrical machines and drives. The paper will cover a wide range of applications highlighting the advantages and challenges of achieving such integration. The paper will also highlight the current research trends.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"17 1","pages":"350-356"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82090208","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409106
M. Tahan, T. Hu
This paper proposed Interacting Multiple Model EKF (IMM-EKF) for estimating the angular speed and rotor position of surface-mounted PMS motor in presence of wide range of process and measurement noises. In this algorithm, four IMM-EKF groups are built based on different noise levels. Appropriate model is selected by a switch function, which get good performance at stable state and robust ability. By this method, on-line and accurate speed and position estimation could be performed to implement sensorless vector control. The simulation results validate the accuracy, stability and robustness of proposed scheme in noisy condition.
{"title":"Speed-sensorless vector control of surface-mounted PMS motor based on modified interacting multiple-model EKF","authors":"M. Tahan, T. Hu","doi":"10.1109/IEMDC.2015.7409106","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409106","url":null,"abstract":"This paper proposed Interacting Multiple Model EKF (IMM-EKF) for estimating the angular speed and rotor position of surface-mounted PMS motor in presence of wide range of process and measurement noises. In this algorithm, four IMM-EKF groups are built based on different noise levels. Appropriate model is selected by a switch function, which get good performance at stable state and robust ability. By this method, on-line and accurate speed and position estimation could be performed to implement sensorless vector control. The simulation results validate the accuracy, stability and robustness of proposed scheme in noisy condition.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"4 1","pages":"510-515"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87699139","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409060
L. Masisi, A. Takbash, P. Pillay
The paper is concerned with the development of a core loss model for a variable flux machine using AlNiCo permanent magnets. A relationship between different magnetization levels and the machine core losses is derived experimentally. An analytical core loss model for non sinusoidal flux waveforms in the PM machine is presented. This model is based on an equivalent sinusoidal waveform. In this model, eddy current loss and hysteresis loss have been estimated based on Maxwell's equation. The analytical results from the proposed model are compared with finite element model (FEM) and experimental results.
{"title":"Core loss performance of a new PM machine topology for electric vehicles","authors":"L. Masisi, A. Takbash, P. Pillay","doi":"10.1109/IEMDC.2015.7409060","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409060","url":null,"abstract":"The paper is concerned with the development of a core loss model for a variable flux machine using AlNiCo permanent magnets. A relationship between different magnetization levels and the machine core losses is derived experimentally. An analytical core loss model for non sinusoidal flux waveforms in the PM machine is presented. This model is based on an equivalent sinusoidal waveform. In this model, eddy current loss and hysteresis loss have been estimated based on Maxwell's equation. The analytical results from the proposed model are compared with finite element model (FEM) and experimental results.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"4 1","pages":"202-207"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88022403","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409121
B. Ge, D. Ludois
Starting from the duality of magnetic reluctance and electric elastance, this paper discusses design features of an axial peg style electrostatic rotating machine. Axial peg style refers to the geometry of the machine. Interdigitated pegs (cylinders) come into, and out of, radial alignment as the machine rotates causing variable capacitance between the stator and rotor. A prototype with peak torque of 0.9 N-m and gap field strength of 14 kV/mm was constructed. The specific torque density of the machine is 0.126 N-m/kg, comparable to fractional horsepower NEMA class induction machines. This was achieved by filling the machine with a dielectric fluid whose relative permittivity is 7.1, rather than ultra-high vacuum typically employed in canonical macro scale electrostatic machine designs. Selected experimental measurements presented include angular capacitance, stall torque, average torque and losses under stall conditions.
{"title":"A 1-phase 48-pole axial peg style electrostatic rotating machine utilizing variable elastance","authors":"B. Ge, D. Ludois","doi":"10.1109/IEMDC.2015.7409121","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409121","url":null,"abstract":"Starting from the duality of magnetic reluctance and electric elastance, this paper discusses design features of an axial peg style electrostatic rotating machine. Axial peg style refers to the geometry of the machine. Interdigitated pegs (cylinders) come into, and out of, radial alignment as the machine rotates causing variable capacitance between the stator and rotor. A prototype with peak torque of 0.9 N-m and gap field strength of 14 kV/mm was constructed. The specific torque density of the machine is 0.126 N-m/kg, comparable to fractional horsepower NEMA class induction machines. This was achieved by filling the machine with a dielectric fluid whose relative permittivity is 7.1, rather than ultra-high vacuum typically employed in canonical macro scale electrostatic machine designs. Selected experimental measurements presented include angular capacitance, stall torque, average torque and losses under stall conditions.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"2 1","pages":"604-610"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88117326","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409297
A. Balamurali, A. Mollaeian, S. M. Sangdehi, N. Kar
Understanding the significance of precise dynamic modeling of electrical machines and the importance of parameter determination for the same, this manuscript proposes a new method of identifying variable inductances and damper parameters of a line-start interior permanent magnet synchronous machine (LSIPMSM) through an off-line improved particle swarm optimization (IPSO). An improved dynamic machine model incorporating the dependence of inductances on magnetizing currents has been developed. Through the combination of experimental test methods conducted on the inverter connected LSIPMSM under varied operating conditions and IPSO algorithm, parameters such as stator and magnetizing inductances and damper parameters have been identified for all conditions. Though conducted on LSIPMSM, the modeling and identification procedures presented in this paper are also applicable to IPMSM and surface magnet PSM with simplified variations. Comparison results of experiments with conventional and improved models are also presented for validation.
{"title":"Parameter identification of permanent magnet synchronous machine based on metaheuristic optimization","authors":"A. Balamurali, A. Mollaeian, S. M. Sangdehi, N. Kar","doi":"10.1109/IEMDC.2015.7409297","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409297","url":null,"abstract":"Understanding the significance of precise dynamic modeling of electrical machines and the importance of parameter determination for the same, this manuscript proposes a new method of identifying variable inductances and damper parameters of a line-start interior permanent magnet synchronous machine (LSIPMSM) through an off-line improved particle swarm optimization (IPSO). An improved dynamic machine model incorporating the dependence of inductances on magnetizing currents has been developed. Through the combination of experimental test methods conducted on the inverter connected LSIPMSM under varied operating conditions and IPSO algorithm, parameters such as stator and magnetizing inductances and damper parameters have been identified for all conditions. Though conducted on LSIPMSM, the modeling and identification procedures presented in this paper are also applicable to IPMSM and surface magnet PSM with simplified variations. Comparison results of experiments with conventional and improved models are also presented for validation.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"9 1","pages":"1729-1734"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83890475","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409113
Gyeong-Deuk Lee, Min-chul Kang, Gyu-Tak Kim
In this paper, cogging torque and unbalanced RMF which occurred in IPM type BLDC motors were investigated regarding as the effect of vibration. The main causes of electromagnetic vibration were the cogging torque and strength of Radial Magnetic Force(RMF). The minimized cogging torque model with notch and the equilibrium RMF model was designed using Design of Experiments(DOE) to reduce vibration. The mentioned models above and the basic model were compared with each other through Finite Element Analysis(FEA) and experiments. As a result, it was conformed that unbalanced RMF affected vibration. And RMF equilibrium is much more effective to vibration than reduction of cogging torque.
{"title":"The equilibrium design of radial magnetic force for reduction of vibration in IPM type BLDC","authors":"Gyeong-Deuk Lee, Min-chul Kang, Gyu-Tak Kim","doi":"10.1109/IEMDC.2015.7409113","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409113","url":null,"abstract":"In this paper, cogging torque and unbalanced RMF which occurred in IPM type BLDC motors were investigated regarding as the effect of vibration. The main causes of electromagnetic vibration were the cogging torque and strength of Radial Magnetic Force(RMF). The minimized cogging torque model with notch and the equilibrium RMF model was designed using Design of Experiments(DOE) to reduce vibration. The mentioned models above and the basic model were compared with each other through Finite Element Analysis(FEA) and experiments. As a result, it was conformed that unbalanced RMF affected vibration. And RMF equilibrium is much more effective to vibration than reduction of cogging torque.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"31 1","pages":"555-561"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86768163","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409211
M. Bali, H. de Gersem, A. Muetze
The cutting process has a substantial influence on the ferromagnetic material properties of electrical steel sheets. In this paper, the properties of the degraded and non-degraded zones result from data obtained by two Epstein frame measurements using sample strips of two different widths. The magnetic characteristics of the degraded and non-degraded material are inserted into a finite-element model, which accounts for arbitrary geometries. The simulation results for the influence of degradation on a stator lamination stack are verified by measurements at three different frequencies and two different materials.
{"title":"Epstein frame measurement based determination of original non-degraded and fully degraded magnetic properties of material submitted to mechanical cutting","authors":"M. Bali, H. de Gersem, A. Muetze","doi":"10.1109/IEMDC.2015.7409211","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409211","url":null,"abstract":"The cutting process has a substantial influence on the ferromagnetic material properties of electrical steel sheets. In this paper, the properties of the degraded and non-degraded zones result from data obtained by two Epstein frame measurements using sample strips of two different widths. The magnetic characteristics of the degraded and non-degraded material are inserted into a finite-element model, which accounts for arbitrary geometries. The simulation results for the influence of degradation on a stator lamination stack are verified by measurements at three different frequencies and two different materials.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"62 1","pages":"1184-1189"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83157765","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 : 2015-05-10DOI: 10.1109/IEMDC.2015.7409168
Ahmed Shehada, R. Krishnan
This paper presents a control strategy for a brushless DC motor (BLDCM) drive with a new converter topology. The new topology is based on the conventional voltage-fed inverter, but includes an additional source such as a capacitor or a battery, and requires connection to the BLDCM neutral. The objective of the proposed control strategy is to control the otherwise unregulated voltage across the additional source, while maintaining commanded speed or torque. Three variations of the control strategy are presented. A detailed simulation model is used to evaluate the performance of the considered converter with proposed control strategy, and compare it to a conventional voltage-fed inverter BLDCM drive. Performance measures include torque per unit current, copper losses per unit current, inverter losses, and efficiency. It is also shown that exact torque and speed control can be exercised at up to twice the rated speed. Simulation results for operation at twice the rated speed with the torque controlled to half the rated value are provided to demonstrate that. This is a major advantage over the conventional BLDCM drive, where speed and torque are usually uncontrolled above rated speed. In addition, the drive is shown to deliver rated power (at rated speed) with only half the dc link voltage.
{"title":"Control methods for a brushless DC motor drive with a new converter topology","authors":"Ahmed Shehada, R. Krishnan","doi":"10.1109/IEMDC.2015.7409168","DOIUrl":"https://doi.org/10.1109/IEMDC.2015.7409168","url":null,"abstract":"This paper presents a control strategy for a brushless DC motor (BLDCM) drive with a new converter topology. The new topology is based on the conventional voltage-fed inverter, but includes an additional source such as a capacitor or a battery, and requires connection to the BLDCM neutral. The objective of the proposed control strategy is to control the otherwise unregulated voltage across the additional source, while maintaining commanded speed or torque. Three variations of the control strategy are presented. A detailed simulation model is used to evaluate the performance of the considered converter with proposed control strategy, and compare it to a conventional voltage-fed inverter BLDCM drive. Performance measures include torque per unit current, copper losses per unit current, inverter losses, and efficiency. It is also shown that exact torque and speed control can be exercised at up to twice the rated speed. Simulation results for operation at twice the rated speed with the torque controlled to half the rated value are provided to demonstrate that. This is a major advantage over the conventional BLDCM drive, where speed and torque are usually uncontrolled above rated speed. In addition, the drive is shown to deliver rated power (at rated speed) with only half the dc link voltage.","PeriodicalId":6477,"journal":{"name":"2015 IEEE International Electric Machines & Drives Conference (IEMDC)","volume":"1 1","pages":"904-909"},"PeriodicalIF":0.0,"publicationDate":"2015-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83672812","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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