Pub Date : 2002-12-10DOI: 10.1109/IAS.2002.1044069
N. Mendalek, F. Fnaiech, K. Al-haddad, L. Dessaint
In this paper a nonlinear multiple-input multiple-output (MIMO) predictive control using optimal control approach is applied to control the currents of a three-phase three-wire voltage source inverter used as a shunt active power filter (AF). The nonlinear active filter state-space representation model is elaborated in the synchronous d-q frame rotating at the mains fundamental frequency. This state-space model is seen as two separate subsystems, namely an inner multiple-input multiple-output model with fast dynamics and an outer single-input single-output model with slow dynamics. The proposed nonlinear MIMO predictive control law is applied to the inner loop forcing the currents to track their references that are extracted from the sensed nonlinear load currents by applying the synchronous reference frame method. The outer DC voltage loop uses a proportional-integral compensator and the compensated error is added to the inner loop d-axis current reference. In addition to good tracking behavior, the predictive control guarantees stability and improves robustness. Simulation results demonstrate the expected performance of the shunt active filter.
{"title":"A non-linear optimal predictive control of a shunt active power filter","authors":"N. Mendalek, F. Fnaiech, K. Al-haddad, L. Dessaint","doi":"10.1109/IAS.2002.1044069","DOIUrl":"https://doi.org/10.1109/IAS.2002.1044069","url":null,"abstract":"In this paper a nonlinear multiple-input multiple-output (MIMO) predictive control using optimal control approach is applied to control the currents of a three-phase three-wire voltage source inverter used as a shunt active power filter (AF). The nonlinear active filter state-space representation model is elaborated in the synchronous d-q frame rotating at the mains fundamental frequency. This state-space model is seen as two separate subsystems, namely an inner multiple-input multiple-output model with fast dynamics and an outer single-input single-output model with slow dynamics. The proposed nonlinear MIMO predictive control law is applied to the inner loop forcing the currents to track their references that are extracted from the sensed nonlinear load currents by applying the synchronous reference frame method. The outer DC voltage loop uses a proportional-integral compensator and the compensated error is added to the inner loop d-axis current reference. In addition to good tracking behavior, the predictive control guarantees stability and improves robustness. Simulation results demonstrate the expected performance of the shunt active filter.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125625376","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 : 2002-12-10DOI: 10.1109/IAS.2002.1044137
F. Wang
This paper studies the coordinated control strategy between the source and load controllers for regenerative back-to-back three level neutral-point-clamped PWM voltage source inverters. The focus is on the coordinated dc link voltage control through a feed-forward power flow control and the coordinated dc link neutral point control. The paper also covers various neutral point control methods including a new linear control scheme. The simulation and experiment results show that, compared with independent source and load control approach, the coordinated approach can significantly improve system response, reduce component stress, and help eliminating nuisance trips.
{"title":"Coordinated control of regenerative three-level neutral point clamped PWM voltage source inverters","authors":"F. Wang","doi":"10.1109/IAS.2002.1044137","DOIUrl":"https://doi.org/10.1109/IAS.2002.1044137","url":null,"abstract":"This paper studies the coordinated control strategy between the source and load controllers for regenerative back-to-back three level neutral-point-clamped PWM voltage source inverters. The focus is on the coordinated dc link voltage control through a feed-forward power flow control and the coordinated dc link neutral point control. The paper also covers various neutral point control methods including a new linear control scheme. The simulation and experiment results show that, compared with independent source and load control approach, the coordinated approach can significantly improve system response, reduce component stress, and help eliminating nuisance trips.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125678808","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 : 2002-12-10DOI: 10.1109/IAS.2002.1042770
M. Cavalcanti, E. D. da Silva, C. Jacobina
This paper proposes a quasi-square-wave DC link (QSWDCL) converter, which improves the performance of an existing topology. The proposed circuit provides zero-DC-link voltage notches, during which the inverter switching is effected, and imposes a minimum DC bus voltage stress to the PWM inverter. Simple design conditions are offered. Simulated and experimental results demonstrate the validity of the proposed topologies.
{"title":"An improved quasi-square-wave DC-link converter","authors":"M. Cavalcanti, E. D. da Silva, C. Jacobina","doi":"10.1109/IAS.2002.1042770","DOIUrl":"https://doi.org/10.1109/IAS.2002.1042770","url":null,"abstract":"This paper proposes a quasi-square-wave DC link (QSWDCL) converter, which improves the performance of an existing topology. The proposed circuit provides zero-DC-link voltage notches, during which the inverter switching is effected, and imposes a minimum DC bus voltage stress to the PWM inverter. Simple design conditions are offered. Simulated and experimental results demonstrate the validity of the proposed topologies.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127905605","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 : 2002-12-10DOI: 10.1109/IAS.2002.1042710
K. Kutluay, I. Çadırcı, A. Yafavi, Y. Çadirci
Design and implementation of a digital controller for universal telecommunication power supply modules are presented. The paper emphasises on converter control strategy, and its implementation by means of parallel operated, dual 8-bit microcontrollers. One of the microcontrollers is employed for user interface purposes, such as long term records, display and alarm facilities, which are inherently slow processes. The fast processing speed required by output voltage setting, current limit, and load current sharing however, is fulfilled by the second microcontroller, which adjusts the output voltages of modules. The proposed dual-processor based digital controller provides an extended operating output voltage range, user programmable current limit setting, serial-communication based active load current sharing between modules, and automatic derating without extra hardware requirement. Overload and output short-circuit protection features are also software-controlled. The controller is tested successfully on six parallel operating, 1.8 W, 0-70 V telecommunication power supplies.
介绍了一种通用通信电源模块数字控制器的设计与实现。本文重点介绍了转换器的控制策略，并利用并行操作的双8位微控制器实现了该策略。其中一个微控制器用于用户界面目的，如长期记录，显示和报警设施，这些本身就是缓慢的过程。而输出电压设定、限流和负载电流分担所需的快速处理速度则由第二个微控制器来实现，该微控制器调节模块的输出电压。所提出的基于双处理器的数字控制器提供了扩展的工作输出电压范围，用户可编程的电流限制设置，基于串行通信的模块之间的主动负载电流共享，以及自动降额，而无需额外的硬件要求。过载和输出短路保护功能也由软件控制。该控制器在6个1.8 W 0-70 V通信电源并联上测试成功。
{"title":"Digital control of universal telecommunication power supplies using dual 8-bit microcontrollers","authors":"K. Kutluay, I. Çadırcı, A. Yafavi, Y. Çadirci","doi":"10.1109/IAS.2002.1042710","DOIUrl":"https://doi.org/10.1109/IAS.2002.1042710","url":null,"abstract":"Design and implementation of a digital controller for universal telecommunication power supply modules are presented. The paper emphasises on converter control strategy, and its implementation by means of parallel operated, dual 8-bit microcontrollers. One of the microcontrollers is employed for user interface purposes, such as long term records, display and alarm facilities, which are inherently slow processes. The fast processing speed required by output voltage setting, current limit, and load current sharing however, is fulfilled by the second microcontroller, which adjusts the output voltages of modules. The proposed dual-processor based digital controller provides an extended operating output voltage range, user programmable current limit setting, serial-communication based active load current sharing between modules, and automatic derating without extra hardware requirement. Overload and output short-circuit protection features are also software-controlled. The controller is tested successfully on six parallel operating, 1.8 W, 0-70 V telecommunication power supplies.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131765270","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 : 2002-12-10DOI: 10.1109/IAS.2002.1043766
Seung-Gi Jeong
Representing the degree of voltage unbalance with the voltage unbalance factor (VUF) derived from symmetrical transformation requires complex phasor manipulations. This paper investigates various ways of representing VUF to facilitate the calculation in field applications. A formula for VUF with readily available line-to-line voltage magnitudes is derived and a straightforward graphical way of determining VUF is proposed. Various approximate methods are examined and it is shown that some alternative measures can be more effective in approximating VUF than conventional ones.
{"title":"Representing line voltage unbalance","authors":"Seung-Gi Jeong","doi":"10.1109/IAS.2002.1043766","DOIUrl":"https://doi.org/10.1109/IAS.2002.1043766","url":null,"abstract":"Representing the degree of voltage unbalance with the voltage unbalance factor (VUF) derived from symmetrical transformation requires complex phasor manipulations. This paper investigates various ways of representing VUF to facilitate the calculation in field applications. A formula for VUF with readily available line-to-line voltage magnitudes is derived and a straightforward graphical way of determining VUF is proposed. Various approximate methods are examined and it is shown that some alternative measures can be more effective in approximating VUF than conventional ones.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132968834","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 : 2002-12-10DOI: 10.1109/IAS.2002.1042713
A. Salazar, A. Maitelli, F.M. de Azevedo
The pulsed plasma nitriding process is widely used nowadays in the treatment and hardening of metallic components. But the voltage regulation on the nitriding chamber, although necessary, is hard to be done, because it depends on the components' dimensions, on pulse's width and on the unstable nature of plasma. Taking this in account, this work proposes the use of a fuzzy-PI controller on the nitriding power source to provide a versatile control, allowing a good voltage regulation under different operational points, i.e. for distinct chamber conditions.
{"title":"Implementation of a fuzzy-PI controller for a pulsed plasma nitriding power source","authors":"A. Salazar, A. Maitelli, F.M. de Azevedo","doi":"10.1109/IAS.2002.1042713","DOIUrl":"https://doi.org/10.1109/IAS.2002.1042713","url":null,"abstract":"The pulsed plasma nitriding process is widely used nowadays in the treatment and hardening of metallic components. But the voltage regulation on the nitriding chamber, although necessary, is hard to be done, because it depends on the components' dimensions, on pulse's width and on the unstable nature of plasma. Taking this in account, this work proposes the use of a fuzzy-PI controller on the nitriding power source to provide a versatile control, allowing a good voltage regulation under different operational points, i.e. for distinct chamber conditions.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130769049","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 : 2002-12-10DOI: 10.1109/IAS.2002.1042809
N. Mutoh, M. Ogata, F. Harashima
The paper describes methods that control EMI noises generated in power converters (rectifier and inverter) by using power printed circuit techniques. Two kinds of differential and common mode noises are generated in motor drive systems. A method is proposed that controls the differential mode noises by symmetrically forming the structure of the positive and negative power transmission lines of the power converter using a four-layer printed power circuit technique. Simulations done using the method show that differential mode currents appearing between the terminals of the power converters and the smoothing capacitors can be almost completely eliminated and the common mode currents are shunted into the artificial ground plane. Another method is also proposed that controls the shunted common mode currents so as to prevent series resonance phenomena by inserting a damping impedance between the frame of the machine and the ground. Experiments verify that the common mode currents generated in the motor drive systems can be effectively reduced by the two proposed methods.
{"title":"New methods to control EMI noises generated in motor drive systems: controlling methods focusing on EMI noise paths","authors":"N. Mutoh, M. Ogata, F. Harashima","doi":"10.1109/IAS.2002.1042809","DOIUrl":"https://doi.org/10.1109/IAS.2002.1042809","url":null,"abstract":"The paper describes methods that control EMI noises generated in power converters (rectifier and inverter) by using power printed circuit techniques. Two kinds of differential and common mode noises are generated in motor drive systems. A method is proposed that controls the differential mode noises by symmetrically forming the structure of the positive and negative power transmission lines of the power converter using a four-layer printed power circuit technique. Simulations done using the method show that differential mode currents appearing between the terminals of the power converters and the smoothing capacitors can be almost completely eliminated and the common mode currents are shunted into the artificial ground plane. Another method is also proposed that controls the shunted common mode currents so as to prevent series resonance phenomena by inserting a damping impedance between the frame of the machine and the ground. Experiments verify that the common mode currents generated in the motor drive systems can be effectively reduced by the two proposed methods.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132881075","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 : 2002-12-10DOI: 10.1109/IAS.2002.1043829
D. Detjen, S. Schroder, R. D. De Doncker
This paper investigates the feasibility of using silicon-silicon bonding technology for combined bipolar-MOSFET-devices (BIMOS) such as MOS-turn-off thyristors (MTO). With the help of this new bonding technique several power MOSFETs are connected to a bipolar disc-type device structure. The MOSFET dies are used to switch the BIMOS-device. At the same time, the reverse conducting diode of the MOSFETs operates as a pn-junction of the classical thyristor structure during on-state. The proposed technology accomplishes the fabrication of BIMOS-devices without bonding wires, which are used in state-of-the-art MTO and ETO devices. Device operation similar to a fully integrated structure can be achieved without the technological problems in manufacturing VLSI-structures on large disc-type devices. In this paper, different MTO type device topologies based on the proposed idea are presented and compared by finite element simulation results.
{"title":"New high-power BIMOS-devices based on silicon-silicon bonding","authors":"D. Detjen, S. Schroder, R. D. De Doncker","doi":"10.1109/IAS.2002.1043829","DOIUrl":"https://doi.org/10.1109/IAS.2002.1043829","url":null,"abstract":"This paper investigates the feasibility of using silicon-silicon bonding technology for combined bipolar-MOSFET-devices (BIMOS) such as MOS-turn-off thyristors (MTO). With the help of this new bonding technique several power MOSFETs are connected to a bipolar disc-type device structure. The MOSFET dies are used to switch the BIMOS-device. At the same time, the reverse conducting diode of the MOSFETs operates as a pn-junction of the classical thyristor structure during on-state. The proposed technology accomplishes the fabrication of BIMOS-devices without bonding wires, which are used in state-of-the-art MTO and ETO devices. Device operation similar to a fully integrated structure can be achieved without the technological problems in manufacturing VLSI-structures on large disc-type devices. In this paper, different MTO type device topologies based on the proposed idea are presented and compared by finite element simulation results.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"12 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133043340","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 : 2002-12-10DOI: 10.1109/IAS.2002.1042803
N. Raju
This paper presents a new method to improve ride-through capability of adjustable speed drives during voltage sags. The method consists of connecting the three-phase neutral to the mid-point of the DC bus when the voltage dips. This changes the front-end from a six-pulse configuration to a series connection of two half-wave connections. The modified configuration provides a higher DC bus voltage and can avoid undervoltage tripping of the drive. The principle of the proposed approach is discussed in detail, and verified through computer simulations. A modification of the method for application in three-wire systems without a neutral is also discussed briefly. An additional function that the proposed circuit can perform is balancing of the DC bus capacitor voltages.
{"title":"Improving voltage sag tolerance of three-phase ASDs through addition of a neutral connection","authors":"N. Raju","doi":"10.1109/IAS.2002.1042803","DOIUrl":"https://doi.org/10.1109/IAS.2002.1042803","url":null,"abstract":"This paper presents a new method to improve ride-through capability of adjustable speed drives during voltage sags. The method consists of connecting the three-phase neutral to the mid-point of the DC bus when the voltage dips. This changes the front-end from a six-pulse configuration to a series connection of two half-wave connections. The modified configuration provides a higher DC bus voltage and can avoid undervoltage tripping of the drive. The principle of the proposed approach is discussed in detail, and verified through computer simulations. A modification of the method for application in three-wire systems without a neutral is also discussed briefly. An additional function that the proposed circuit can perform is balancing of the DC bus capacitor voltages.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132180271","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 : 2002-12-10DOI: 10.1109/IAS.2002.1043815
Y. Lai, Fu-San Shyu, Yung-Hsin Chang
It is well known that small power brushless DC motor (BLDCM) drives have been widely applied to the information technology industry, especially for fan and spindle applications. For small power applications of BLDCM drives, due to the use of battery and limited space for heat dissipation, reduction of power consumption is one of the main concerns for the development of pulse-width modulation (PWM) technique. This paper presents a novel PWM technique for small power BLDCM drives, which significantly reduces the conduction losses, and thereby dramatically reducing the heat dissipation. Comparative results with conventional PWM technique are fully explored to highlight the advantages of the presented novel technique. Experimental results derived from an FPGA-based spindle drive are presented to confirm the theoretical analysis.
{"title":"Novel pulse-width modulation technique with loss reduction for small power brushless DC motor drives","authors":"Y. Lai, Fu-San Shyu, Yung-Hsin Chang","doi":"10.1109/IAS.2002.1043815","DOIUrl":"https://doi.org/10.1109/IAS.2002.1043815","url":null,"abstract":"It is well known that small power brushless DC motor (BLDCM) drives have been widely applied to the information technology industry, especially for fan and spindle applications. For small power applications of BLDCM drives, due to the use of battery and limited space for heat dissipation, reduction of power consumption is one of the main concerns for the development of pulse-width modulation (PWM) technique. This paper presents a novel PWM technique for small power BLDCM drives, which significantly reduces the conduction losses, and thereby dramatically reducing the heat dissipation. Comparative results with conventional PWM technique are fully explored to highlight the advantages of the presented novel technique. Experimental results derived from an FPGA-based spindle drive are presented to confirm the theoretical analysis.","PeriodicalId":202482,"journal":{"name":"Conference Record of the 2002 IEEE Industry Applications Conference. 37th IAS Annual Meeting (Cat. No.02CH37344)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127387457","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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