Pub Date : 2014-09-11DOI: 10.1109/ICIT.2014.6894984
K. Kaur, T. Saha, S. N. Mahato, S. Banerjee
A sensor less wind speed estimation scheme for variable-speed wind turbine generators has been analysed in this paper. Neural network principles are applied for sensor less wind speed estimation. Model of one pitch controlled horizontal axis wind turbine along with DOIG based generation system has been used for this study. The aerodynamic characteristics of the wind turbine are approximated by a radial basis function network based nonlinear input-output mapping. Based on this mapping, the wind speed is estimated from the measured turbine mechanical power, turbine angular speed and pitch angle. The resulting WTG system efficiently and reliably estimates the wind speed without any mechanical anemometers.
{"title":"Wind speed estimation based control of Stand-Alone DOIG for wind energy conversion system","authors":"K. Kaur, T. Saha, S. N. Mahato, S. Banerjee","doi":"10.1109/ICIT.2014.6894984","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894984","url":null,"abstract":"A sensor less wind speed estimation scheme for variable-speed wind turbine generators has been analysed in this paper. Neural network principles are applied for sensor less wind speed estimation. Model of one pitch controlled horizontal axis wind turbine along with DOIG based generation system has been used for this study. The aerodynamic characteristics of the wind turbine are approximated by a radial basis function network based nonlinear input-output mapping. Based on this mapping, the wind speed is estimated from the measured turbine mechanical power, turbine angular speed and pitch angle. The resulting WTG system efficiently and reliably estimates the wind speed without any mechanical anemometers.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127539777","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894894
Ali Abusnina, D. Kudenko, Rolf Roth
Gaussian processes are emerging as a new option in soft sensor building techniques. They can provide predictions with associated uncertainty measure that can be of great importance in open and closed loop control applications. Most importantly, they have a relatively simple model structure as they are totally determined by their mean and covariance functions. The selection of the covariance function determines the overall performance of the soft sensor. This paper conducts an empirical comparison using 8 different data sets from various industrial applications between the squared exponential covariance function - used in all previously published Gaussian process-based soft sensors - and the Matérn class covariance function. The contribution of the paper is to recommend the use of the Matérn class covariance function for soft sensors, since in our experiments its accuracy is at least that of the squared exponential covariance function, and in some cases higher. In addition, results on condition numbers indicate that the Matérn class covariance function results in a prediction model that is less sensitive to numerical errors.
{"title":"Selection of covariance functions in Gaussian process-based soft sensors","authors":"Ali Abusnina, D. Kudenko, Rolf Roth","doi":"10.1109/ICIT.2014.6894894","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894894","url":null,"abstract":"Gaussian processes are emerging as a new option in soft sensor building techniques. They can provide predictions with associated uncertainty measure that can be of great importance in open and closed loop control applications. Most importantly, they have a relatively simple model structure as they are totally determined by their mean and covariance functions. The selection of the covariance function determines the overall performance of the soft sensor. This paper conducts an empirical comparison using 8 different data sets from various industrial applications between the squared exponential covariance function - used in all previously published Gaussian process-based soft sensors - and the Matérn class covariance function. The contribution of the paper is to recommend the use of the Matérn class covariance function for soft sensors, since in our experiments its accuracy is at least that of the squared exponential covariance function, and in some cases higher. In addition, results on condition numbers indicate that the Matérn class covariance function results in a prediction model that is less sensitive to numerical errors.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132883853","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894865
W. Choi, Sung‐Jun Park, H. Nam, C. Jin, B. Shin
This paper proposes a new topology for the soft-switching boost PFC converter. The proposed converter comprises of a transformer, a snubber capacitor, a snubber inductors, three diodes. The primary coil of the transformer is connected to the input side of the converter and functions as the main inductor, and the secondary winding to the snubber circuit. Integrity of the proposed converter is validated using both theoretical analysis and PSIM simulation.
{"title":"High power factor soft-switching PFC power converter for battery charger","authors":"W. Choi, Sung‐Jun Park, H. Nam, C. Jin, B. Shin","doi":"10.1109/ICIT.2014.6894865","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894865","url":null,"abstract":"This paper proposes a new topology for the soft-switching boost PFC converter. The proposed converter comprises of a transformer, a snubber capacitor, a snubber inductors, three diodes. The primary coil of the transformer is connected to the input side of the converter and functions as the main inductor, and the secondary winding to the snubber circuit. Integrity of the proposed converter is validated using both theoretical analysis and PSIM simulation.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132076010","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894948
H. Shareef, A. Mohamed, A. H. Mutlag
This paper presents a scheme for controlling the flow of current from a grid connected photovoltaic (PV) generator while supplying power to the utility grid. The proposed system utilizes a fuzzy logic controller (FLC) to control the injected current through the PV inverter switches. The controller employs error and change of error in current as inputs. In the design, asymmetrical triangular membership function (MF) with five linguistic variables (LV) is used for the inputs while asymmetrical triangular MF with nine LV is adopted for the output. The proposed inverter control system along with 435V PV module is then developed in Matlab/Simulink to illustrate the effectiveness of the controller. The results show that the controller can effectively supplies rated root mean square voltage of 240V. Furthermore, the total harmonic distortion of the current waveform is found to be 1.45%, which meets with international standard.
{"title":"A current control strategy for a grid connected PV system using fuzzy logic controller","authors":"H. Shareef, A. Mohamed, A. H. Mutlag","doi":"10.1109/ICIT.2014.6894948","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894948","url":null,"abstract":"This paper presents a scheme for controlling the flow of current from a grid connected photovoltaic (PV) generator while supplying power to the utility grid. The proposed system utilizes a fuzzy logic controller (FLC) to control the injected current through the PV inverter switches. The controller employs error and change of error in current as inputs. In the design, asymmetrical triangular membership function (MF) with five linguistic variables (LV) is used for the inputs while asymmetrical triangular MF with nine LV is adopted for the output. The proposed inverter control system along with 435V PV module is then developed in Matlab/Simulink to illustrate the effectiveness of the controller. The results show that the controller can effectively supplies rated root mean square voltage of 240V. Furthermore, the total harmonic distortion of the current waveform is found to be 1.45%, which meets with international standard.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125342272","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894906
Yuanlong Wei, Mincheol Lee
This paper presents a development of guide-dog robot system for visually impaired. Based on a hall-sensor joystick and ultrasonic sensors, a “smart rope” system is designed for the human-robot interaction. In this system, multiple functions are provided for the self-walking in urban system, such as following, navigation and obstacle avoidance. To distinguish between small involuntary force and the intended navigational movement, a fuzzy logic control method is applied to improve the accuracy for the “smart rope” system manipulation. To compensate the lack of visual sense of visually impaired, a smart phone with camera is utilized as the robot vision, in order to detect the traffic lights and the zebra crossing. A fast vision recognition approach is provided based on Adaboosting and Template matching combined algorithm. For the evaluation of proposed method, an integrated system is implemented to the mobile robot platform. The performance of both interactive system and vision system are analyzed after the experiment in the urban environment. System's accuracy, usefulness and adaptability are verified. The experimental results showed that this new designed guide-dog robot system is suitable and effective to assist the visually impaired for the self-walking.
{"title":"A guide-dog robot system research for the visually impaired","authors":"Yuanlong Wei, Mincheol Lee","doi":"10.1109/ICIT.2014.6894906","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894906","url":null,"abstract":"This paper presents a development of guide-dog robot system for visually impaired. Based on a hall-sensor joystick and ultrasonic sensors, a “smart rope” system is designed for the human-robot interaction. In this system, multiple functions are provided for the self-walking in urban system, such as following, navigation and obstacle avoidance. To distinguish between small involuntary force and the intended navigational movement, a fuzzy logic control method is applied to improve the accuracy for the “smart rope” system manipulation. To compensate the lack of visual sense of visually impaired, a smart phone with camera is utilized as the robot vision, in order to detect the traffic lights and the zebra crossing. A fast vision recognition approach is provided based on Adaboosting and Template matching combined algorithm. For the evaluation of proposed method, an integrated system is implemented to the mobile robot platform. The performance of both interactive system and vision system are analyzed after the experiment in the urban environment. System's accuracy, usefulness and adaptability are verified. The experimental results showed that this new designed guide-dog robot system is suitable and effective to assist the visually impaired for the self-walking.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121192949","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6895019
H. Hashimoto, Mizuki Nakajima, S. Kawata, Sanggyu Shin, Toshiyuki Murao
In this paper, we propose an objective skill level evaluation method for Taijiquan. The proposed skill level evaluation method utilizes a logarithmic distribution diagram of curvature for spiral arm motion and a cross-correlation for whole body motion. In order to demonstrate a possibility of the proposed method, we present experimental results with a Kinect sensor.
{"title":"Skill level evaluation of Taijiquan based on 3D body motion analysis — Via logalithm distribution diagram and phase analysis","authors":"H. Hashimoto, Mizuki Nakajima, S. Kawata, Sanggyu Shin, Toshiyuki Murao","doi":"10.1109/ICIT.2014.6895019","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6895019","url":null,"abstract":"In this paper, we propose an objective skill level evaluation method for Taijiquan. The proposed skill level evaluation method utilizes a logarithmic distribution diagram of curvature for spiral arm motion and a cross-correlation for whole body motion. In order to demonstrate a possibility of the proposed method, we present experimental results with a Kinect sensor.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125199385","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6895011
Zhenyao Xu, Dong-Hee Lee, Jin-Woo Ahn
In this paper, a novel two-phase switched reluctance motor (SRM) with T-type rotor pole surface is proposed for a high speed air blower. The air blower has unidirectional rotation and requires a wide positive torque region without torque dead zone. To achieve the requirements, asymmetric inductance profile is considered. Unlike the previous research method, which tries to modify the air-gap to get the asymmetric inductance, the proposed method tries to keep the constant air-gap and modify the stack length of the rotor according to the rotor position to acquire the asymmetric inductance. Compared with stepper type, the proposed structure not only inherits the torque characteristics of the stepper type, but also improves the utilization of the material. That is, the material used in the proposed type is less than that in the stepper type. To verify the validity of the proposed structure, finite element method (FEM) is employed to get the characteristics of the conventional, stepper type and proposed SRM. Finally, the simulation results verify the validity of the proposed structure.
{"title":"Characteristics analysis of a novel two-phase SRM with T-type rotor pole surface","authors":"Zhenyao Xu, Dong-Hee Lee, Jin-Woo Ahn","doi":"10.1109/ICIT.2014.6895011","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6895011","url":null,"abstract":"In this paper, a novel two-phase switched reluctance motor (SRM) with T-type rotor pole surface is proposed for a high speed air blower. The air blower has unidirectional rotation and requires a wide positive torque region without torque dead zone. To achieve the requirements, asymmetric inductance profile is considered. Unlike the previous research method, which tries to modify the air-gap to get the asymmetric inductance, the proposed method tries to keep the constant air-gap and modify the stack length of the rotor according to the rotor position to acquire the asymmetric inductance. Compared with stepper type, the proposed structure not only inherits the torque characteristics of the stepper type, but also improves the utilization of the material. That is, the material used in the proposed type is less than that in the stepper type. To verify the validity of the proposed structure, finite element method (FEM) is employed to get the characteristics of the conventional, stepper type and proposed SRM. Finally, the simulation results verify the validity of the proposed structure.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122906587","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 : 2014-09-11DOI: 10.6113/JPE.2014.14.5.815
Guoen Cao, Heejun Kim
An improved bridgeless interleaved boost PFC rectifier is proposed to improve power efficiency and component utilization in this paper. By combining the conventional bridge-less PFC circuit and the interleaved technology, the proposed rectifier is comprised of two interleaved boost branches without the front-end diode bridge. Auxiliary diodes are employed to eliminate undesired circulating loop. The magnetic component utilization is improved by symmetrically coupling two inductors on unique core. According to the interleaved approach, each switch can operate in the whole-line cycle. Moreover, this circuit not only decreases the current stress of the switching devices but also reduces the current and voltage ripple. As operating in critical-conduction-mode (CrM), all the switches can achieve soft-switching characteristics to reduce the switching loss and evidently raise the conversion efficiency. Using a conventional interleaved controller, simple control scheme can be employed to the proposed converter. The operational principle and theoretical analysis of the proposed converter are presented. Finally, an 600 W experimental prototype was built to verify the theoretical analysis and feasibility of the proposed converter. The system efficiency was achieved up to 97.3% with very low current THD.
{"title":"An improved bridgeless interleaved boost PFC rectifier with optimized magnetic utilization and reduced sensing noise","authors":"Guoen Cao, Heejun Kim","doi":"10.6113/JPE.2014.14.5.815","DOIUrl":"https://doi.org/10.6113/JPE.2014.14.5.815","url":null,"abstract":"An improved bridgeless interleaved boost PFC rectifier is proposed to improve power efficiency and component utilization in this paper. By combining the conventional bridge-less PFC circuit and the interleaved technology, the proposed rectifier is comprised of two interleaved boost branches without the front-end diode bridge. Auxiliary diodes are employed to eliminate undesired circulating loop. The magnetic component utilization is improved by symmetrically coupling two inductors on unique core. According to the interleaved approach, each switch can operate in the whole-line cycle. Moreover, this circuit not only decreases the current stress of the switching devices but also reduces the current and voltage ripple. As operating in critical-conduction-mode (CrM), all the switches can achieve soft-switching characteristics to reduce the switching loss and evidently raise the conversion efficiency. Using a conventional interleaved controller, simple control scheme can be employed to the proposed converter. The operational principle and theoretical analysis of the proposed converter are presented. Finally, an 600 W experimental prototype was built to verify the theoretical analysis and feasibility of the proposed converter. The system efficiency was achieved up to 97.3% with very low current THD.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134016714","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894878
HeungGyoon Harry Choi, Kyu-Sun Chung, Ge Li, Tae-Won Heo
Increasing strong demand for smaller insulated transformers, an ultra-small transformer has been developed by adopting an insulated hybrid structure with the size of W16.5 × L19.5 × H10.5 mm^3, whose volume is 65 % smaller than conventional insulated transformers. Our new transformer has been improved in terms of noise reduction by 5-15 dB, power efficiency increase by 2 %, and production efficiency by 50 %. Relevant analyses are to be given.
{"title":"Ultra-small transformer using insulated hybrid structure for AC adapters of smart devices","authors":"HeungGyoon Harry Choi, Kyu-Sun Chung, Ge Li, Tae-Won Heo","doi":"10.1109/ICIT.2014.6894878","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894878","url":null,"abstract":"Increasing strong demand for smaller insulated transformers, an ultra-small transformer has been developed by adopting an insulated hybrid structure with the size of W16.5 × L19.5 × H10.5 mm^3, whose volume is 65 % smaller than conventional insulated transformers. Our new transformer has been improved in terms of noise reduction by 5-15 dB, power efficiency increase by 2 %, and production efficiency by 50 %. Relevant analyses are to be given.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114215600","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894976
G. Fourlas, S. Karkanis, G. Karras, K. Kyriakopoulos
This paper presents a model based actuator fault diagnosis for a four wheel skid steering mobile robot (SSMR). In this approach we use structural analysis based technique in order to generate residuals. The goal is to detect actuators faults as early as possible and provide a timely warning. For this purpose we develop the kinematic model of the mobile robot that serves to the creation of the structural model of the system. This technique provides the parity equations which can be used as residual generators. The main advantage of the proposed method is that can offers feasible solution to residual generation for nonlinear systems. As a robotic platform, was used the mobile robot Pioneer 3-AT.
{"title":"Model based actuator fault diagnosis for a mobile robot","authors":"G. Fourlas, S. Karkanis, G. Karras, K. Kyriakopoulos","doi":"10.1109/ICIT.2014.6894976","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894976","url":null,"abstract":"This paper presents a model based actuator fault diagnosis for a four wheel skid steering mobile robot (SSMR). In this approach we use structural analysis based technique in order to generate residuals. The goal is to detect actuators faults as early as possible and provide a timely warning. For this purpose we develop the kinematic model of the mobile robot that serves to the creation of the structural model of the system. This technique provides the parity equations which can be used as residual generators. The main advantage of the proposed method is that can offers feasible solution to residual generation for nonlinear systems. As a robotic platform, was used the mobile robot Pioneer 3-AT.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"268 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115851780","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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