Pub Date : 2011-04-18DOI: 10.1109/IAPEC.2011.5779851
M. Jamali, M. Mirzaie, S. Gholamian, S. Cherati
The phenomenon of magnetizing inrush is a transient condition, which occurs primarily when a transformer is energized. The magnitude of inrush current may be as high as ten times or more times of transformer rated current that causes malfunction of protection system. So, for safe running of a transformer, it is necessary to distinguish inrush current from fault currents. In this paper, a wavelet-based technique has been used to discriminate inrush current from faults. For this purpose, a wavelet transform (WT) concept is presented and a criterion based on different behaviors of the differential currents under fault and inrush conditions have been derived. For checking the validity of the wavelet-based technique in discriminating of inrush currents from faults a three-phase 20/63 kV transformer has been simulated in Maxwell software that is based on finite element method (FEM). Then, obtained data from different situations have been used in MATALB software for implementation of the WT technique.
{"title":"A wavelet-based technique for discrimination of inrush currents from faults in transformers coupled with finite element method","authors":"M. Jamali, M. Mirzaie, S. Gholamian, S. Cherati","doi":"10.1109/IAPEC.2011.5779851","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779851","url":null,"abstract":"The phenomenon of magnetizing inrush is a transient condition, which occurs primarily when a transformer is energized. The magnitude of inrush current may be as high as ten times or more times of transformer rated current that causes malfunction of protection system. So, for safe running of a transformer, it is necessary to distinguish inrush current from fault currents. In this paper, a wavelet-based technique has been used to discriminate inrush current from faults. For this purpose, a wavelet transform (WT) concept is presented and a criterion based on different behaviors of the differential currents under fault and inrush conditions have been derived. For checking the validity of the wavelet-based technique in discriminating of inrush currents from faults a three-phase 20/63 kV transformer has been simulated in Maxwell software that is based on finite element method (FEM). Then, obtained data from different situations have been used in MATALB software for implementation of the WT technique.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129987841","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779854
J. M. Lazi, Z. Ibrahim, M. Sulaiman, I. W. Jamaludin, M. Y. Lada
Dual motor drives fed by single inverter are purposely designed to reduced sizes and cost with respect to single motor drives fed by single inverter. This paper presents the speed responses behavior of Dual Permanent Magnet Synchronous Motor (PMSM) driven base on two different PWM control schemes, which are Space Vector Pulse Width Modulation (SVPWM) and Hysteresis Current Controller. These two techniques are compared for wide range of speed and for variation of load. MATLAB/Simulink has been chosen as the simulation tools. The comparison between SVPWM controller and Hysteresis Current Controller for Dual PMSM fed by single inverter is presented. Both techniques show satisfactory speed regulation for a wide range of speed either with load, no load or variation of load.
{"title":"Performance comparison of SVPWM and Hysteresis Current Control for Dual motor drives","authors":"J. M. Lazi, Z. Ibrahim, M. Sulaiman, I. W. Jamaludin, M. Y. Lada","doi":"10.1109/IAPEC.2011.5779854","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779854","url":null,"abstract":"Dual motor drives fed by single inverter are purposely designed to reduced sizes and cost with respect to single motor drives fed by single inverter. This paper presents the speed responses behavior of Dual Permanent Magnet Synchronous Motor (PMSM) driven base on two different PWM control schemes, which are Space Vector Pulse Width Modulation (SVPWM) and Hysteresis Current Controller. These two techniques are compared for wide range of speed and for variation of load. MATLAB/Simulink has been chosen as the simulation tools. The comparison between SVPWM controller and Hysteresis Current Controller for Dual PMSM fed by single inverter is presented. Both techniques show satisfactory speed regulation for a wide range of speed either with load, no load or variation of load.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125980994","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779839
Ehsan Behrouzian, A. Tabesh, Farzad Bahrainian, A. Zamani
This paper reports on design of power electronics for photovoltaic (PV) energy system of an offshore remote sensing apparatus. Challenges in design of a PV energy system for a marine application are investigated and the design limitations compared to inland PV system are discussed. The designed system includes PV cells as the main source of energy, electric storage (battery), maximum power point tracking (MPPT) and protection circuitries. An MPPT algorithm based on measuring the slope of the PV power-voltage curves is presented which can be implemented with simple analog electronic circuits. The MPPT circuit uses Sepic converter as a core and it also includes a protection unit for maintaining the battery voltage in a safe range. The performance of the proposed MPPT algorithm in presence of measurement noises is verified using a circuit simulation software tool (PSCAD). Simulation results verify that the algorithm appropriately regulates the voltage of PV cells at MPP and it is robust against measurement noises for a signal-to-noise ratio above -2db.
{"title":"Power electronics for photovoltaic energy system of an Oceanographic buoy","authors":"Ehsan Behrouzian, A. Tabesh, Farzad Bahrainian, A. Zamani","doi":"10.1109/IAPEC.2011.5779839","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779839","url":null,"abstract":"This paper reports on design of power electronics for photovoltaic (PV) energy system of an offshore remote sensing apparatus. Challenges in design of a PV energy system for a marine application are investigated and the design limitations compared to inland PV system are discussed. The designed system includes PV cells as the main source of energy, electric storage (battery), maximum power point tracking (MPPT) and protection circuitries. An MPPT algorithm based on measuring the slope of the PV power-voltage curves is presented which can be implemented with simple analog electronic circuits. The MPPT circuit uses Sepic converter as a core and it also includes a protection unit for maintaining the battery voltage in a safe range. The performance of the proposed MPPT algorithm in presence of measurement noises is verified using a circuit simulation software tool (PSCAD). Simulation results verify that the algorithm appropriately regulates the voltage of PV cells at MPP and it is robust against measurement noises for a signal-to-noise ratio above -2db.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116830527","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779861
B. Das, N. Watson, Yonghe Liu
The 6-pulse controlled rectifier circuit is very well known. For proper operation of the 6-pulse rectifier, it is necessary to synchronise the firing signals with the mains voltage, else the operation of the rectifier is affected. A firing angle controller, without using any phase lock loop (PLL), is described here. This scheme employs the dq-reference frame to estimate the magnitude and phase angle of the fundamental component of the mains voltage. This method offers structural simplicity and immunity to mains voltage unbalance, harmonics and voltage sag etc.
{"title":"6-pulse controlled rectifier synchronisation method","authors":"B. Das, N. Watson, Yonghe Liu","doi":"10.1109/IAPEC.2011.5779861","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779861","url":null,"abstract":"The 6-pulse controlled rectifier circuit is very well known. For proper operation of the 6-pulse rectifier, it is necessary to synchronise the firing signals with the mains voltage, else the operation of the rectifier is affected. A firing angle controller, without using any phase lock loop (PLL), is described here. This scheme employs the dq-reference frame to estimate the magnitude and phase angle of the fundamental component of the mains voltage. This method offers structural simplicity and immunity to mains voltage unbalance, harmonics and voltage sag etc.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"175 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128529989","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779842
B. Jacob, M. Baiju
A Spread Spectrum Modulation scheme based on Space Vector for three level inverter is proposed in this paper. The scheme disperses the power spectrum of the inverter output voltage as a wide-spectrum noise. The vector space of inverter reference space vector region is divided into voronoi regions to find out switching vectors. A new method is presented to code these voronoi regions with Vector Quantization using instantaneous reference phase amplitudes without using lookup table. The space-vector diagram of three-level inverter is simplified to two-level space-vector diagram by the principle of mapping. The switching vectors are determined for two-level inverter using the proposed scheme and these switching vectors are then translated to the actual switching vectors of the three-level inverter by reverse mapping. The proposed scheme naturally selects the outer vectors in the over-modulation condition and hence results in a smooth transition from linear to over-modulation region. The scheme is implemented for 2-HP three phase induction motor driven by three-level cascaded inverter topology.
{"title":"Space Vector based Spread Spectrum Modulation scheme for three-level inverters","authors":"B. Jacob, M. Baiju","doi":"10.1109/IAPEC.2011.5779842","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779842","url":null,"abstract":"A Spread Spectrum Modulation scheme based on Space Vector for three level inverter is proposed in this paper. The scheme disperses the power spectrum of the inverter output voltage as a wide-spectrum noise. The vector space of inverter reference space vector region is divided into voronoi regions to find out switching vectors. A new method is presented to code these voronoi regions with Vector Quantization using instantaneous reference phase amplitudes without using lookup table. The space-vector diagram of three-level inverter is simplified to two-level space-vector diagram by the principle of mapping. The switching vectors are determined for two-level inverter using the proposed scheme and these switching vectors are then translated to the actual switching vectors of the three-level inverter by reverse mapping. The proposed scheme naturally selects the outer vectors in the over-modulation condition and hence results in a smooth transition from linear to over-modulation region. The scheme is implemented for 2-HP three phase induction motor driven by three-level cascaded inverter topology.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115725891","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779865
Low Wen Yao, J. Aziz
This paper discusses the Lithium Ion battery modeling by using equivalent circuit model with nonlinear transfer resistance. The modeling is done by using MATLAB/Simulink. A constant current pulse test is used to extract the model's parameters and the procedures are presented in details. Then the voltage responses of the conventional model, proposed model and MATLAB Li-ion cell model are compared. From the comparison, it reveals that the proposed model producing a better accuracy compared to conventional equivalent circuit model.
{"title":"Modeling of Lithium Ion battery with nonlinear transfer resistance","authors":"Low Wen Yao, J. Aziz","doi":"10.1109/IAPEC.2011.5779865","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779865","url":null,"abstract":"This paper discusses the Lithium Ion battery modeling by using equivalent circuit model with nonlinear transfer resistance. The modeling is done by using MATLAB/Simulink. A constant current pulse test is used to extract the model's parameters and the procedures are presented in details. Then the voltage responses of the conventional model, proposed model and MATLAB Li-ion cell model are compared. From the comparison, it reveals that the proposed model producing a better accuracy compared to conventional equivalent circuit model.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126088856","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779843
M. A. A. Bakar, R. Nagarajan, A. R. M. Saad
This work presents a simple marker-based person detection method for a mobile robot that can follow a person in indoor environments. Expensive laser range finders or RFID which can provide very accurate range measurements have been used by several researchers for person detection. Recently, vision based approaches have been popular for person detection within a group of multiple people using stereo cameras. In this paper of proposed implementation, an inexpensive single camera has been used to acquire video frames to detect a specific target person and determine its position. A new detection method using color and shape based marker technique has been advanced in this work. The experimental results show that the proposed algorithm can detect a target person under various conditions such as marker features and lighting conditions.
{"title":"Development of a doctor following mobile robot with Mono-vision based marker detection","authors":"M. A. A. Bakar, R. Nagarajan, A. R. M. Saad","doi":"10.1109/IAPEC.2011.5779843","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779843","url":null,"abstract":"This work presents a simple marker-based person detection method for a mobile robot that can follow a person in indoor environments. Expensive laser range finders or RFID which can provide very accurate range measurements have been used by several researchers for person detection. Recently, vision based approaches have been popular for person detection within a group of multiple people using stereo cameras. In this paper of proposed implementation, an inexpensive single camera has been used to acquire video frames to detect a specific target person and determine its position. A new detection method using color and shape based marker technique has been advanced in this work. The experimental results show that the proposed algorithm can detect a target person under various conditions such as marker features and lighting conditions.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"213 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129974930","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779864
S. Cherati, N. A. Azli, S. Ayob, A. Mortezaei
This paper presents the design of current mode PI controller for single-phase PWM inverter. The controller is comprised of inductor current as the inner loop and output voltage as the outer feedback loop. The control design is carried out using Sisotool, which is provided in Matlab. By using this tool, users can examine the effects of changing the gain control values to system's transient response and stability, simultaneously. Hence, simplify and speed up the control design process. To evaluate the performance of the designed controller, the inverter is simulated under several types of load disturbances. From the result, it is shown that the designed controller exhibits a good transient response i.e. fast rising and settling time with small overshoot when subjected to step load disturbance.
{"title":"Design of a current mode PI controller for a single-phase PWM inverter","authors":"S. Cherati, N. A. Azli, S. Ayob, A. Mortezaei","doi":"10.1109/IAPEC.2011.5779864","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779864","url":null,"abstract":"This paper presents the design of current mode PI controller for single-phase PWM inverter. The controller is comprised of inductor current as the inner loop and output voltage as the outer feedback loop. The control design is carried out using Sisotool, which is provided in Matlab. By using this tool, users can examine the effects of changing the gain control values to system's transient response and stability, simultaneously. Hence, simplify and speed up the control design process. To evaluate the performance of the designed controller, the inverter is simulated under several types of load disturbances. From the result, it is shown that the designed controller exhibits a good transient response i.e. fast rising and settling time with small overshoot when subjected to step load disturbance.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114653647","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779857
H. Vahedi, A. Sheikholeslami, M. Bina
Variable switching process is the main issue in practical implementation of fixed band hysteresis current controller in active power filters (APF) that increases the switching frequency and switching losses in power systems. Preventing this case, the Adaptive Hysteresis Current Control (AHCC) has been introduced and developed by many researchers. By this way, The Hysteresis Band (HB) will change adaptively by system parameters in order to control the switching speed and fix the switching frequency. In this paper a revisory method for the hysteresis bandwidth calculation procedure is proposed that makes switching frequency invariable significantly. The APF Simulations using proposed method (NHB) in Matlab/Simulink environment has been done. Results including switching frequency and current source TDH have been given to prove the efficiency of this method.
{"title":"A novel hysteresis bandwidth (NHB) calculation to fix the switching frequency employed in active power filter","authors":"H. Vahedi, A. Sheikholeslami, M. Bina","doi":"10.1109/IAPEC.2011.5779857","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779857","url":null,"abstract":"Variable switching process is the main issue in practical implementation of fixed band hysteresis current controller in active power filters (APF) that increases the switching frequency and switching losses in power systems. Preventing this case, the Adaptive Hysteresis Current Control (AHCC) has been introduced and developed by many researchers. By this way, The Hysteresis Band (HB) will change adaptively by system parameters in order to control the switching speed and fix the switching frequency. In this paper a revisory method for the hysteresis bandwidth calculation procedure is proposed that makes switching frequency invariable significantly. The APF Simulations using proposed method (NHB) in Matlab/Simulink environment has been done. Results including switching frequency and current source TDH have been given to prove the efficiency of this method.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131972358","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 : 2011-04-18DOI: 10.1109/IAPEC.2011.5779859
Y. Al-Mashhadany
The classical controllers algorithm is both simple and reliable, and has been applied to thousands of control loops in various industrial applications over the past 60 years (89%-90% of applications). This paper presents the neuro-fuzzy controller incorporates fuzzy logic algorithm with a five-layer artificial neural network (ANN) structure. The conventional controller is replaced by Adaptive Neuro-Fuzzy Inference System (ANFIS) before that made the identification process of ANFIS controller by the data base of classical controller to be consider as initial condition for controlling process with this system. The simulation of the design is achieved by using Matlab Ver. 2010a. Chopper-Fed DC Motor Drive (Continuous / Discrete) are consider as case study. Satisfactory results are obtained explaining the ability of ANFIS controller to control with the dynamic high nonlinear system and can be get very good results by tunes the fuzzy controller.
{"title":"Modeling and simulation of Adaptive Neuro-Fuzzy controller for Chopper-Fed DC Motor Drive","authors":"Y. Al-Mashhadany","doi":"10.1109/IAPEC.2011.5779859","DOIUrl":"https://doi.org/10.1109/IAPEC.2011.5779859","url":null,"abstract":"The classical controllers algorithm is both simple and reliable, and has been applied to thousands of control loops in various industrial applications over the past 60 years (89%-90% of applications). This paper presents the neuro-fuzzy controller incorporates fuzzy logic algorithm with a five-layer artificial neural network (ANN) structure. The conventional controller is replaced by Adaptive Neuro-Fuzzy Inference System (ANFIS) before that made the identification process of ANFIS controller by the data base of classical controller to be consider as initial condition for controlling process with this system. The simulation of the design is achieved by using Matlab Ver. 2010a. Chopper-Fed DC Motor Drive (Continuous / Discrete) are consider as case study. Satisfactory results are obtained explaining the ability of ANFIS controller to control with the dynamic high nonlinear system and can be get very good results by tunes the fuzzy controller.","PeriodicalId":386166,"journal":{"name":"2011 IEEE Applied Power Electronics Colloquium (IAPEC)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121657381","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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