S. Ademi, A. Ridge, R. McMahon, H. Kelly, P. Clifton
This paper presents the construction and testing of a ferrite-based axial flux permanent magnet machine (PMg) for applications in wind power generation. This technology offers significant levelized cost of energy reductions via capital expenditure and operating expense savings - a crucial objective for the offshore industry. The direct-drive (DD) PMG technology uses ferrite magnets to create the magnetic field, which is a significant source of cost reduction. The use of ferrite could also eliminate an industry wide reliance on neodymium iron boron, the scarce and expensive rare-earth magnet used in existing designs. Another benefit of using ferrite-based design is that it is less sensitive to the cooling problems that currently face existing DD-PMGs. Further technical advantages come in the form of magnetically balanced axial design, optimized magnet and aluminium/copper ratio, insensitivity to air gap and cogging elimination. This paper details aspects of design, construction, thermal performance and testing of a nominal 250 kW power rating prototype.
{"title":"DESIGN AND TESTING OF A 250 kW FERRITEBASED AXIAL FLUX PERMANENT MAGNET FOR APPLICATION IN WIND POWER GENERATION","authors":"S. Ademi, A. Ridge, R. McMahon, H. Kelly, P. Clifton","doi":"10.1049/icp.2021.1045","DOIUrl":"https://doi.org/10.1049/icp.2021.1045","url":null,"abstract":"This paper presents the construction and testing of a ferrite-based axial flux permanent magnet machine (PMg) for applications in wind power generation. This technology offers significant levelized cost of energy reductions via capital expenditure and operating expense savings - a crucial objective for the offshore industry. The direct-drive (DD) PMG technology uses ferrite magnets to create the magnetic field, which is a significant source of cost reduction. The use of ferrite could also eliminate an industry wide reliance on neodymium iron boron, the scarce and expensive rare-earth magnet used in existing designs. Another benefit of using ferrite-based design is that it is less sensitive to the cooling problems that currently face existing DD-PMGs. Further technical advantages come in the form of magnetically balanced axial design, optimized magnet and aluminium/copper ratio, insensitivity to air gap and cogging elimination. This paper details aspects of design, construction, thermal performance and testing of a nominal 250 kW power rating prototype.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124679068","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}
This work proposes a straight forward approach for the utilization of Direct Torque Control (DTC) algorithm to drive an openend winding Synchronous Reluctance Machine (SynRM). The drive is based on an Indirect Matrix Converter (IMC) with Dual Voltage Source Inverters (DVSI) on the output, thus eliminating the need for a dc-link. The proposed approach only utilizes the the output vectors that eliminate the contribution of the dual inverter to the Common Mode Voltage (CMV), improving the drive lifespan by reducing the machine bearing currents. The proposed Direct Torque Controller is based on four hysteretic controllers to allow the control of Torque, Flux, Zero Sequence Current on the machine while allowing input power factor correction by controlling the grid current.
{"title":"Open-end Winding Synchronous Reluctance Sensorless Drive based on Indirect Matrix Converter with Dual VSI Output","authors":"A. Bento, R. Luís, S. Pinto, F. Silva","doi":"10.1049/icp.2021.1159","DOIUrl":"https://doi.org/10.1049/icp.2021.1159","url":null,"abstract":"This work proposes a straight forward approach for the utilization of Direct Torque Control (DTC) algorithm to drive an openend winding Synchronous Reluctance Machine (SynRM). The drive is based on an Indirect Matrix Converter (IMC) with Dual Voltage Source Inverters (DVSI) on the output, thus eliminating the need for a dc-link. The proposed approach only utilizes the the output vectors that eliminate the contribution of the dual inverter to the Common Mode Voltage (CMV), improving the drive lifespan by reducing the machine bearing currents. The proposed Direct Torque Controller is based on four hysteretic controllers to allow the control of Torque, Flux, Zero Sequence Current on the machine while allowing input power factor correction by controlling the grid current.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126989929","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}
Resonant Switched Capacitor (SC) DC-DC converters are showing potential for use in medium to high-power applications. The high-cell count in these applications means that for a given voltage conversion ratio there are theoretically a large number of alternative topologies that can be synthesised. However, each of these topologies may exhibit different competing characteristics, for example total VA rating of capacitors, total VA rating of switches, number of switches and individual switch voltage rating. Obtaining an optimum topology in terms of given design constraints is therefore important requirement. This paper builds on previous work by the authors by presenting a method for the automatic calculation of the voltage ratings of the components in a SC converter. This result along with earlier work, allows for the calculation of VA ratings, which are an important metric when comparing competing circuits. In addition, a new Canonical Cell topology is presented that extends the range of SC circuits that can be analysed using this method, to cover so-called Ladder circuits. The method is validated against detailed Spice simulations and measurements from a hardware prototype.
{"title":"AUTO-APPRAISAL OF VOLTAGE RATING FOR SWITCHED-CAPACITOR DC-DC CONVERTERS","authors":"H. Taghizadeh, A. Cross, N. Narayanan-Kuruveettil","doi":"10.1049/icp.2021.0993","DOIUrl":"https://doi.org/10.1049/icp.2021.0993","url":null,"abstract":"Resonant Switched Capacitor (SC) DC-DC converters are showing potential for use in medium to high-power applications. The high-cell count in these applications means that for a given voltage conversion ratio there are theoretically a large number of alternative topologies that can be synthesised. However, each of these topologies may exhibit different competing characteristics, for example total VA rating of capacitors, total VA rating of switches, number of switches and individual switch voltage rating. Obtaining an optimum topology in terms of given design constraints is therefore important requirement. This paper builds on previous work by the authors by presenting a method for the automatic calculation of the voltage ratings of the components in a SC converter. This result along with earlier work, allows for the calculation of VA ratings, which are an important metric when comparing competing circuits. In addition, a new Canonical Cell topology is presented that extends the range of SC circuits that can be analysed using this method, to cover so-called Ladder circuits. The method is validated against detailed Spice simulations and measurements from a hardware prototype.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127656983","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}
{"title":"A LARGE-SCALE BATTERY ENERGY STORAGE SYSTEM SIMULATION TOOL FOR STUDYING CELL VARIATION","authors":"Z. Wang, J. Davidson, M. Foster","doi":"10.1049/icp.2021.1117","DOIUrl":"https://doi.org/10.1049/icp.2021.1117","url":null,"abstract":"","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123937282","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}
Disturbance and resonance effects may cause tilt vibrations in bearingless disc motors. Typically, these vibrations are only very poorly dampened by passive stabilization torques. In this paper, two strategies to actively suppress tilt vibrations are proposed: additional tilt damping by flux modulation and by radial rotor position deflection. Tilt oscillations can be reduced by modulating the magnetic air-gap flux with a d-axis current as a function of the tilt angle and its first derivative. Another option is to move the rotor towards a position offering increased tilt stiffness, depending on the tilt oscillation amplitude and speed. In order to analyse the effect, mathematical models of the two methods considering parameters of a bearingless flux-switching disc motor prototype are set up and analyzed numerically.
{"title":"ACTIVE TILT COMPENSATION METHODS FOR BEARINGLESS DISC MOTORS","authors":"B. Klammer, H. Mitterhofer, W. Gruber","doi":"10.1049/icp.2021.0990","DOIUrl":"https://doi.org/10.1049/icp.2021.0990","url":null,"abstract":"Disturbance and resonance effects may cause tilt vibrations in bearingless disc motors. Typically, these vibrations are only very poorly dampened by passive stabilization torques. In this paper, two strategies to actively suppress tilt vibrations are proposed: additional tilt damping by flux modulation and by radial rotor position deflection. Tilt oscillations can be reduced by modulating the magnetic air-gap flux with a d-axis current as a function of the tilt angle and its first derivative. Another option is to move the rotor towards a position offering increased tilt stiffness, depending on the tilt oscillation amplitude and speed. In order to analyse the effect, mathematical models of the two methods considering parameters of a bearingless flux-switching disc motor prototype are set up and analyzed numerically.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115483394","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}
L. Hallemans, J. Zwysen, S. Ravyts, G. Van den Broeck, S. Schlimpert, G. Beckers, J. Driesen
Due to a strong drive towards a higher power density of electrical drivetrains and the impact of cooling on their reliability, the thermal characterisation and monitoring of these systems is gaining importance. The power electronic devices driving the electrical motor in this system are often integrated within one power module, complicating temperature measurements and monitoring of the semiconductor devices. Therefore, accurate thermal models of these modules are necessary. The main challenge remains to model these thermal properties sufficiently accurate to estimate the device temperatures, while maintaining an evaluation speed fast enough to ensure safe operating temperatures in real-time. Furthermore, in the search for enhanced cooling methods, it may be interesting to compare cooling designs using simulations before or instead of experiments. To this end, this paper develops and compares the accuracy of a 3D grey-box Lumped Parameter Model of an IGBT module coupled with an interchangeable cooling model with two 1D Lumped Parameter Models. The 3D model is based on a Finite Element representation, while the 1D models are based solely on datasheet information. The different model types are discussed and compared regarding their accuracy using simulation and experimental results.
{"title":"AN EXPERIMENTAL COMPARISON OF THERMAL MODELLING TECHNIQUES FOR IGBT MODULES IN ELECTRICAL DRIVETRAINS","authors":"L. Hallemans, J. Zwysen, S. Ravyts, G. Van den Broeck, S. Schlimpert, G. Beckers, J. Driesen","doi":"10.1049/icp.2021.1098","DOIUrl":"https://doi.org/10.1049/icp.2021.1098","url":null,"abstract":"Due to a strong drive towards a higher power density of electrical drivetrains and the impact of cooling on their reliability, the thermal characterisation and monitoring of these systems is gaining importance. The power electronic devices driving the electrical motor in this system are often integrated within one power module, complicating temperature measurements and monitoring of the semiconductor devices. Therefore, accurate thermal models of these modules are necessary. The main challenge remains to model these thermal properties sufficiently accurate to estimate the device temperatures, while maintaining an evaluation speed fast enough to ensure safe operating temperatures in real-time. Furthermore, in the search for enhanced cooling methods, it may be interesting to compare cooling designs using simulations before or instead of experiments. To this end, this paper develops and compares the accuracy of a 3D grey-box Lumped Parameter Model of an IGBT module coupled with an interchangeable cooling model with two 1D Lumped Parameter Models. The 3D model is based on a Finite Element representation, while the 1D models are based solely on datasheet information. The different model types are discussed and compared regarding their accuracy using simulation and experimental results.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114279795","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}
This paper proposes a novel Direct Speed Model Predictive Control (DSMPC) for PMSM drive. The developed strategy takes into consideration the difference between the electromagnetic and mechanical time constant. The predictions with different sampling periods in speed and current models of PMSM are analyzed in detail. Meanwhile, the linear estimation method is employed to avoid the large amount of calculation of torque prediction. The load torque observer and delay compensation are achieved as well. Compared with the traditional DSMPC in simulations and experiments, the proposed strategy shows a better performance.
{"title":"Direct Speed Model Predictive Control with two-time scale for PMSM Drives","authors":"F. Chai, L. Gao, Y. Yu, L. Geng","doi":"10.1049/icp.2021.1109","DOIUrl":"https://doi.org/10.1049/icp.2021.1109","url":null,"abstract":"This paper proposes a novel Direct Speed Model Predictive Control (DSMPC) for PMSM drive. The developed strategy takes into consideration the difference between the electromagnetic and mechanical time constant. The predictions with different sampling periods in speed and current models of PMSM are analyzed in detail. Meanwhile, the linear estimation method is employed to avoid the large amount of calculation of torque prediction. The load torque observer and delay compensation are achieved as well. Compared with the traditional DSMPC in simulations and experiments, the proposed strategy shows a better performance.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"727 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115136018","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}
J. Ortiz-Gonzalez, R. Wu, Haimeng Wu, Xiang Wang, Volker Pickert, Philip A. Mawby, O. Alatise
This paper presents a comprehensive study of the impact of the gate voltage on the switching and ON-state performance of SiC MOSFETs. It is well known that the gate oxide in SiC MOSFETs is not as reliable as that in silicon MOSFETs due to increased fixed oxide and interface traps. Numerous studies have shown reduced performance on time-dependent dielectric breakdown (TDDB) and oxide robustness in SiC MOSFETs compared to silicon devices. On the one hand, a high ON-state gate-source voltage VGS is required for proper channel inversion, low ON-state loss and fast switching while on the other hand, a lower ONstate VGS reduces the electrical stress on the gate oxide and improves long term reliability. Understanding the implications of the selected gate voltage on the operation of the power device will be fundamental for achieving an optimal balance between electrical performance and gate oxide reliability. This paper shows that reducing the maximum gate driver supply voltage VGG only affects turn-ON losses while turn-OFF losses are independent of VGG. The experimental characterisation is complemented with electrothermal simulations to evaluate the impact of the gate voltage on the operation of a converter. The paper shows that reducing VGG by 10% causes an increase of 7.6% in the device losses and 1.4 °C in junction temperature in simulated converter operation. Furthermore, if the switching speed is increased by means of reducing the gate resistance, the impact of the conduction losses can be compensated. These results are fundamental for balancing system efficiency and reliability in SiC MOSFETs.
{"title":"OPTIMISATION OF THE GATE VOLTAGE IN SiC MOSFETS: EFFICIENCY VS RELIABILITY","authors":"J. Ortiz-Gonzalez, R. Wu, Haimeng Wu, Xiang Wang, Volker Pickert, Philip A. Mawby, O. Alatise","doi":"10.1049/icp.2021.1043","DOIUrl":"https://doi.org/10.1049/icp.2021.1043","url":null,"abstract":"This paper presents a comprehensive study of the impact of the gate voltage on the switching and ON-state performance of SiC MOSFETs. It is well known that the gate oxide in SiC MOSFETs is not as reliable as that in silicon MOSFETs due to increased fixed oxide and interface traps. Numerous studies have shown reduced performance on time-dependent dielectric breakdown (TDDB) and oxide robustness in SiC MOSFETs compared to silicon devices. On the one hand, a high ON-state gate-source voltage VGS is required for proper channel inversion, low ON-state loss and fast switching while on the other hand, a lower ONstate VGS reduces the electrical stress on the gate oxide and improves long term reliability. Understanding the implications of the selected gate voltage on the operation of the power device will be fundamental for achieving an optimal balance between electrical performance and gate oxide reliability. This paper shows that reducing the maximum gate driver supply voltage VGG only affects turn-ON losses while turn-OFF losses are independent of VGG. The experimental characterisation is complemented with electrothermal simulations to evaluate the impact of the gate voltage on the operation of a converter. The paper shows that reducing VGG by 10% causes an increase of 7.6% in the device losses and 1.4 °C in junction temperature in simulated converter operation. Furthermore, if the switching speed is increased by means of reducing the gate resistance, the impact of the conduction losses can be compensated. These results are fundamental for balancing system efficiency and reliability in SiC MOSFETs.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"24 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114085894","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}
This paper presents the challenges of creating a cooling system for a permanent magnet machine with high power density. A hybrid air/water cooling system is presented with the aim of enhancing the cooling performance of the stator. Finite element calculations are first used to determine the winding loss in the stator, including skin and proximity effect. The effect of air speed, turbulence of the air flow and liquid speed have been discussed to find the best working point, using CFD simulation. The performance of the hybrid cooling system has been evaluated and design recommendations established.
{"title":"HYBRID COOLING DESIGN OF PERMANENT MAGNET SYNCHRONOUS MACHINES","authors":"Q. Li, X. Shen, B. Mecrow, X. Deng","doi":"10.1049/icp.2021.1044","DOIUrl":"https://doi.org/10.1049/icp.2021.1044","url":null,"abstract":"This paper presents the challenges of creating a cooling system for a permanent magnet machine with high power density. A hybrid air/water cooling system is presented with the aim of enhancing the cooling performance of the stator. Finite element calculations are first used to determine the winding loss in the stator, including skin and proximity effect. The effect of air speed, turbulence of the air flow and liquid speed have been discussed to find the best working point, using CFD simulation. The performance of the hybrid cooling system has been evaluated and design recommendations established.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123784826","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}
In recent years, there has been an increasing interest in utilising Differential Power Processing converters (DPP) in Photovoltaic (PV) applications to achieve the maximum power point tracking (MPPT), minimum losses and high efficiency under unequal lighting conditions. This paper presents a novel Series and Parallel (SP) DPP converters scheme, with a proper control technique to optimise the system output power under mismatch conditions compared to that of a conventional 2×2 SP array which is protected with bypass diodes. The simulation results of such system show significant improvements in the total power of the SP-DPP system under PSCs.
{"title":"Series-Parallel Differential Power Processing Scheme for Maximised Power Extraction from Mismatched Photovoltaic Panels","authors":"M. Etarhouni, B. Chong, L. Zhang","doi":"10.1049/icp.2021.0997","DOIUrl":"https://doi.org/10.1049/icp.2021.0997","url":null,"abstract":"In recent years, there has been an increasing interest in utilising Differential Power Processing converters (DPP) in Photovoltaic (PV) applications to achieve the maximum power point tracking (MPPT), minimum losses and high efficiency under unequal lighting conditions. This paper presents a novel Series and Parallel (SP) DPP converters scheme, with a proper control technique to optimise the system output power under mismatch conditions compared to that of a conventional 2×2 SP array which is protected with bypass diodes. The simulation results of such system show significant improvements in the total power of the SP-DPP system under PSCs.","PeriodicalId":188371,"journal":{"name":"The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020)","volume":"36 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131550017","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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