Pub Date : 2015-02-12DOI: 10.1109/PEAC.2014.7038014
C. Yoon, Xiongfei Wang, F. Faria da Silva, C. Bak, F. Blaabjerg
This paper investigates the dynamic interactions of current controllers for multi-paralleled, grid-connected inverters. The consequent harmonics instability phenomena, which features with oscillations above the fundamental frequency, are evaluated by the impedance-based stability criterion. The frequency range of effective impedance-based stability analysis is first identified. The effect of each inverter on the system harmonic instability is then identified by case studies on different groups of inverters. Lastly, the PSCAD/EMTDC simulations on a system with five passively-damped, LCL-filtered inverters are performed to verify theoretical analysis. It shows that the impedance-based stability analysis results agree with the time-domain simulations provided that the frequency of concerns are around the half of the Nyquist sampling frequency.
{"title":"Harmonic stability assessment for multi-paralleled, grid-connected inverters","authors":"C. Yoon, Xiongfei Wang, F. Faria da Silva, C. Bak, F. Blaabjerg","doi":"10.1109/PEAC.2014.7038014","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7038014","url":null,"abstract":"This paper investigates the dynamic interactions of current controllers for multi-paralleled, grid-connected inverters. The consequent harmonics instability phenomena, which features with oscillations above the fundamental frequency, are evaluated by the impedance-based stability criterion. The frequency range of effective impedance-based stability analysis is first identified. The effect of each inverter on the system harmonic instability is then identified by case studies on different groups of inverters. Lastly, the PSCAD/EMTDC simulations on a system with five passively-damped, LCL-filtered inverters are performed to verify theoretical analysis. It shows that the impedance-based stability analysis results agree with the time-domain simulations provided that the frequency of concerns are around the half of the Nyquist sampling frequency.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126545082","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 : 2014-11-05DOI: 10.1109/PEAC.2014.7037903
Zhibin Zhou, F. Scuiller, J. Charpentier, M. Benbouzid, Tianhao Tang
Owning to the predictability of tidal current resources, marine tidal current energy is considered to be a reliable and promising renewable power source for coastal areas or some remote islands. During the last 10 years, various original horizontal axis and vertical axis marine current turbines (MCT) have been developed around the world. Although various projects have been reported in the state-of-the-art research papers in recent years, many of these projects were only at the design stage when the papers were published. In fact, some projects do not have any further developments during the several years after the first reporting. In this paper, up-to-date information about large tidal turbine projects over 500 kW is focused. The newest achievements of these large tidal current turbine technologies are presented. These technologies represent the industrial solutions for several pre-commercial MCT farm projects in the coming years. This paper provides a useful background for researchers in the marine turbine energy domain.
{"title":"An up-to-date review of large marine tidal current turbine technologies","authors":"Zhibin Zhou, F. Scuiller, J. Charpentier, M. Benbouzid, Tianhao Tang","doi":"10.1109/PEAC.2014.7037903","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037903","url":null,"abstract":"Owning to the predictability of tidal current resources, marine tidal current energy is considered to be a reliable and promising renewable power source for coastal areas or some remote islands. During the last 10 years, various original horizontal axis and vertical axis marine current turbines (MCT) have been developed around the world. Although various projects have been reported in the state-of-the-art research papers in recent years, many of these projects were only at the design stage when the papers were published. In fact, some projects do not have any further developments during the several years after the first reporting. In this paper, up-to-date information about large tidal turbine projects over 500 kW is focused. The newest achievements of these large tidal current turbine technologies are presented. These technologies represent the industrial solutions for several pre-commercial MCT farm projects in the coming years. This paper provides a useful background for researchers in the marine turbine energy domain.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115182671","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 : 2014-11-05DOI: 10.1109/PEAC.2014.7037878
H. Titah-Benbouzid, M. Benbouzid
The potential of electric power generation from marine renewable energy is enormous. Ocean waves are being recognized as a resource to be exploited for the sustainable generation of electrical power. The high load factors resulting from the fluid properties and the predictable resource characteristics make ocean waves particularly attractive for power generation and advantageous when compared to other renewable energies. Regarding this emerging and promising area of research, this paper presents a complete review of wave energy technologies describing, analyzing and fixing many of the concepts behind wave energy conversion. The proposed review will specifically highlights the main wave energy conversion projects around the world at different levels (demonstration stage, in production, and commercialized projects). In addition, a discussion will highlight challenges that wave energy converters need to overcome to become commercially competitive in the global energy market.
{"title":"Ocean wave energy extraction: Up-to-date technologies review and evaluation","authors":"H. Titah-Benbouzid, M. Benbouzid","doi":"10.1109/PEAC.2014.7037878","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037878","url":null,"abstract":"The potential of electric power generation from marine renewable energy is enormous. Ocean waves are being recognized as a resource to be exploited for the sustainable generation of electrical power. The high load factors resulting from the fluid properties and the predictable resource characteristics make ocean waves particularly attractive for power generation and advantageous when compared to other renewable energies. Regarding this emerging and promising area of research, this paper presents a complete review of wave energy technologies describing, analyzing and fixing many of the concepts behind wave energy conversion. The proposed review will specifically highlights the main wave energy conversion projects around the world at different levels (demonstration stage, in production, and commercialized projects). In addition, a discussion will highlight challenges that wave energy converters need to overcome to become commercially competitive in the global energy market.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133250288","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 : 2014-11-05DOI: 10.1109/PEAC.2014.7037877
S. Olaya, J. Bourgeot, M. Benbouzid
This paper deals with the optimal control of a self-reacting Wave Energy Converter (WEC) where the reaction force is obtained using a damping-plate. Model Predictive Control (MPC) is applied for unconstrained and constrained input control cases. Objective function attempting to optimise the power generation is directly formulated as an absorbed power maximisation problem and thus no optimal reference, such as buoy and/or spar velocity, is required. Moreover, rather than using the full WEC model in the optimisation problem which can be time-consuming, and because of linear assumptions, we propose the use of a phenomenologically one-body equivalent model derived using the Thévenin's theorem.
{"title":"Optimal control for a self-reacting point absorber: A one-body equivalent model approach","authors":"S. Olaya, J. Bourgeot, M. Benbouzid","doi":"10.1109/PEAC.2014.7037877","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037877","url":null,"abstract":"This paper deals with the optimal control of a self-reacting Wave Energy Converter (WEC) where the reaction force is obtained using a damping-plate. Model Predictive Control (MPC) is applied for unconstrained and constrained input control cases. Objective function attempting to optimise the power generation is directly formulated as an absorbed power maximisation problem and thus no optimal reference, such as buoy and/or spar velocity, is required. Moreover, rather than using the full WEC model in the optimisation problem which can be time-consuming, and because of linear assumptions, we propose the use of a phenomenologically one-body equivalent model derived using the Thévenin's theorem.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"358 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115942871","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 : 2014-11-05DOI: 10.1109/PEAC.2014.7037902
Sofiane Djebarri, J. Charpentier, F. Scuiller, M. Benbouzid
The aim of the paper is to compare the design of direct-drive permanent-magnet (PM) generators associated with horizontal axis tidal turbines. The turbine/generator couplings are examined. These turbine/generator couplings consist of a POD and Rim-driven assembly. In a Rim-Driven association the electrical generator active parts are inserted in a duct surrounding the blades. For POD generator insertion, the electrical machine is placed in a nacelle located on the turbine axis. To achieve the generators sizing, a design rated point related to an industrial MCT is defined. The used design models include an electromagnetic model which is linked to a thermal model in an optimization procedure that goals to minimize the active parts cost. Firstly, a single rotor/single stator PM axial flux generator and a radial flux PM generator are designed for a rim-driven MCT specification. For these generators sizing, a comparison of the machines active parts and the machines geometrical dimensions are carried out. Secondly, radial flux PM generators are designed for Rim-Driven and POD assembly and a comparison is performed for this study case. Finally, the influence of the POD diameter on the generator electromagnetic design is studied. It shows that the active parts costs are minimized, when the generator diameter is around 1/3 of the turbine diameter for the considered specifications. These performed comparisons between the considered study cases aims to help designers in their technologies choices.
{"title":"Comparison of direct-drive PM generators for tidal turbines","authors":"Sofiane Djebarri, J. Charpentier, F. Scuiller, M. Benbouzid","doi":"10.1109/PEAC.2014.7037902","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037902","url":null,"abstract":"The aim of the paper is to compare the design of direct-drive permanent-magnet (PM) generators associated with horizontal axis tidal turbines. The turbine/generator couplings are examined. These turbine/generator couplings consist of a POD and Rim-driven assembly. In a Rim-Driven association the electrical generator active parts are inserted in a duct surrounding the blades. For POD generator insertion, the electrical machine is placed in a nacelle located on the turbine axis. To achieve the generators sizing, a design rated point related to an industrial MCT is defined. The used design models include an electromagnetic model which is linked to a thermal model in an optimization procedure that goals to minimize the active parts cost. Firstly, a single rotor/single stator PM axial flux generator and a radial flux PM generator are designed for a rim-driven MCT specification. For these generators sizing, a comparison of the machines active parts and the machines geometrical dimensions are carried out. Secondly, radial flux PM generators are designed for Rim-Driven and POD assembly and a comparison is performed for this study case. Finally, the influence of the POD diameter on the generator electromagnetic design is studied. It shows that the active parts costs are minimized, when the generator diameter is around 1/3 of the turbine diameter for the considered specifications. These performed comparisons between the considered study cases aims to help designers in their technologies choices.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131946640","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037923
Maria C. Mira, A. Knott, M. Andersen
This paper presents an analysis and comparison of magnetics structures in a tapped boost converter for LED applications. The magnetic structure is a coupled inductor which is analyzed in a conventional wire-wound core as well as in a planar structure for different interleaving winding arrangements. The analysis is performed in terms of leakage inductance, winding capacitance and winding loss. Efficiency measurements are performed to verify the effect on the converter performance.
{"title":"Analysis and comparison of magnetic structures in a tapped boost converter for LED applications","authors":"Maria C. Mira, A. Knott, M. Andersen","doi":"10.1109/PEAC.2014.7037923","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037923","url":null,"abstract":"This paper presents an analysis and comparison of magnetics structures in a tapped boost converter for LED applications. The magnetic structure is a coupled inductor which is analyzed in a conventional wire-wound core as well as in a planar structure for different interleaving winding arrangements. The analysis is performed in terms of leakage inductance, winding capacitance and winding loss. Efficiency measurements are performed to verify the effect on the converter performance.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115223108","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7038026
Ye Jiang, T. Lu, Liqiang Yuan, Zhengming Zhao, F. He
Based on the existing voltage balancing scheme for two series HV-IGBTs (High voltage insulated gate bipolar transistors) with active clamping and status feedback, this paper focuses on the characteristics of IGBT with active clamping circuit. First, the previous series IGBT model is improved according to the experiment results in order to give accurate feedback signal in the active clamping sub-circuit. Then the effect of the load current, the gate drive delay and clamping threshold on feedback signal is studied by simulation. According to the analysis above, the voltage balancing scheme with status feedback is applied to multiple series IGBTs and is proved feasible by simulation.
{"title":"Simulation analysis of active clamping circuit with status feedback for HV-IGBTs","authors":"Ye Jiang, T. Lu, Liqiang Yuan, Zhengming Zhao, F. He","doi":"10.1109/PEAC.2014.7038026","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7038026","url":null,"abstract":"Based on the existing voltage balancing scheme for two series HV-IGBTs (High voltage insulated gate bipolar transistors) with active clamping and status feedback, this paper focuses on the characteristics of IGBT with active clamping circuit. First, the previous series IGBT model is improved according to the experiment results in order to give accurate feedback signal in the active clamping sub-circuit. Then the effect of the load current, the gate drive delay and clamping threshold on feedback signal is studied by simulation. According to the analysis above, the voltage balancing scheme with status feedback is applied to multiple series IGBTs and is proved feasible by simulation.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116685266","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037937
Zheng Wang, Jing Chen, Bing Zhang, Yang Zheng
This paper proposes and studies the phase-shifted chaotic space vector modulation (SVM) scheme for harmonics performance improvement in paralleled voltage-source inverters fed permanent magnet synchronous motor (PMSM) drive. By using the proposed scheme, the current harmonics around the switching frequency and some of its multiples in PMSM are eliminated. Besides, the peaky harmonics around all multiples of switching frequency are spread out such that the peaky harmonics are further suppressed with the irregular switching frequencies. The experiments are given to verify the performance of the proposed scheme in this paper.
{"title":"Phase-shifted chaotic SVM for harmonic performance improvement in paralleled voltage-source inverters fed PMSM drive","authors":"Zheng Wang, Jing Chen, Bing Zhang, Yang Zheng","doi":"10.1109/PEAC.2014.7037937","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037937","url":null,"abstract":"This paper proposes and studies the phase-shifted chaotic space vector modulation (SVM) scheme for harmonics performance improvement in paralleled voltage-source inverters fed permanent magnet synchronous motor (PMSM) drive. By using the proposed scheme, the current harmonics around the switching frequency and some of its multiples in PMSM are eliminated. Besides, the peaky harmonics around all multiples of switching frequency are spread out such that the peaky harmonics are further suppressed with the irregular switching frequencies. The experiments are given to verify the performance of the proposed scheme in this paper.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125142052","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037915
Leilei Guo, Xing Zhang, Shuying Yang, Z. Xie, R. Cao
The speed sensorless control method, which is based on the extended electromotive force (EEMF) model of interior permanent magnet synchronous motor, is difficult to make into use and its parameter dependence is strong. So a method to simplify the EEMF model was proposed and a simplified full order state and sliding mode observer (FOSSMO) was designed in order to achieve sensorless control. In addition, a simplified stator flux and electromagnetic torque observation method was presented. Then, torque closed-loop control system without speed sensor is established. The simulation and experimental research show that the proposed sensorless stator flux and electromagnetic torque observation method is independent of all the inductance and permanent magnet flux linkage parameters and the transient characteristic of the sensorless torque closed-loop control system is good.
{"title":"Speed sensorless torque closed-loop vector control of IPMSM","authors":"Leilei Guo, Xing Zhang, Shuying Yang, Z. Xie, R. Cao","doi":"10.1109/PEAC.2014.7037915","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037915","url":null,"abstract":"The speed sensorless control method, which is based on the extended electromotive force (EEMF) model of interior permanent magnet synchronous motor, is difficult to make into use and its parameter dependence is strong. So a method to simplify the EEMF model was proposed and a simplified full order state and sliding mode observer (FOSSMO) was designed in order to achieve sensorless control. In addition, a simplified stator flux and electromagnetic torque observation method was presented. Then, torque closed-loop control system without speed sensor is established. The simulation and experimental research show that the proposed sensorless stator flux and electromagnetic torque observation method is independent of all the inductance and permanent magnet flux linkage parameters and the transient characteristic of the sensorless torque closed-loop control system is good.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126149571","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 : 2014-11-01DOI: 10.1109/PEAC.2014.7037883
Xiaoli Lai, Fei Liu, Kai Deng, Qi Gao, X. Zha
Short-circuiting in dc lines affects the security and reliability of dc microgrid greatly. A short-circuit current calculation method for low-voltage dc microgrid is proposed in this paper. To solve the calculation of short-circuit current, a line model of bipolar which includes π type equivalent circuits, solid-state bidirectional switches with snubber circuits and freewheeling branches is adopted. The line current under different short-circuit fault types in dc bus is discussed and the circuit working mechanisms before and after solid-state switches action are analyzed, and then the analytic expressions of the line fault current are derived. Besides, the freewheeling loop of the short-circuit current is also analyzed after the removal of fault. The correctness of the analytic expressions is verified by MATLAB/Simulink simulations.
{"title":"A short-circuit current calculation method for low-voltage DC microgrid","authors":"Xiaoli Lai, Fei Liu, Kai Deng, Qi Gao, X. Zha","doi":"10.1109/PEAC.2014.7037883","DOIUrl":"https://doi.org/10.1109/PEAC.2014.7037883","url":null,"abstract":"Short-circuiting in dc lines affects the security and reliability of dc microgrid greatly. A short-circuit current calculation method for low-voltage dc microgrid is proposed in this paper. To solve the calculation of short-circuit current, a line model of bipolar which includes π type equivalent circuits, solid-state bidirectional switches with snubber circuits and freewheeling branches is adopted. The line current under different short-circuit fault types in dc bus is discussed and the circuit working mechanisms before and after solid-state switches action are analyzed, and then the analytic expressions of the line fault current are derived. Besides, the freewheeling loop of the short-circuit current is also analyzed after the removal of fault. The correctness of the analytic expressions is verified by MATLAB/Simulink simulations.","PeriodicalId":309780,"journal":{"name":"2014 International Power Electronics and Application Conference and Exposition","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116092519","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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