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V. Garg - One of the best experts on this subject based on the ideXlab platform.
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a novel polygon based 18 pulse ac dc converter for vector controlled induction motor drives
IEEE Transactions on Power Electronics, 2007Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper presents a novel configuration of an autotransformer based 18-pulse ac-dc converter for improving the power quality at the point of common coupling (PCC) in variable frequency induction motor drives (VFIMDs). The polygon based connection of autotransformer for achieving 18-pulse rectification is utilized to result in reduction in rating of the magnetics. The design of the autotransformer is carried out for an 18-pulse ac-dc converter feeding a vector controlled induction motor drive (VCIMD). Moreover, the autotransformer design is modified for making it suitable for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The effect of load variation on VCIMD is also studied and the performance of the proposed 18-pulse ac-dc converter is compared in terms of different power quality indices on both ac as well as dc side with other ac-dc converters. A laboratory prototype of the proposed autotransformer based 18-pulse ac-dc converter feeding a 10-hp induction motor drive is developed to verify the design and simulated results
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Harmonic Mitigation in AC–DC Converters for Vector Controlled Induction Motor Drives
IEEE Transactions on Energy Conversion, 2007Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper deals with autotransformer-based multipulse ac--dc converters with reduced magnetics feeding vector controlled induction motor drives for improving the power quality at the point of common coupling. The proposed 12-pulse ac--dc converter-based harmonic mitigator consists of an autotransformer alongwith a passive shunt filter tuned for 11th harmonic frequency. This results in the elimination of 5th, 7th, and 11th harmonic currents. Similarly, the proposed 18-pulse ac--dc converter-based harmonic mitigator eliminates the 5th, 7th, 11th, 13th, and 17th harmonic currents, thereby improving the power quality at ac mains. The experimentation is carried out on the developed prototype of Autotransformers-based ac--dc converters. Different power quality indexes of the proposed 12-pulse and 18-pulse ac--dc converters are obtained from simulation and verified from experimental results.
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a twelve phase ac dc converter for power quality improvement in direct torque controlled induction motor drives
Conference on Industrial Electronics and Applications, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper presents the design and analysis of a star connected autotransformer based twelve-phase AC-DC converter for improving power quality at the point of common coupling (PCC) in direct torque controlled induction motor drives (DTCIMDs). A star connected autotransformer with five windings per phase is used to realize the twelve-phase AC-DC converter. The basic design equations are derived to calculate the number of turns in different windings for achieving harmonic reduction in the proposed autotransformer based AC-DC converter. The designed twelve-phase AC-DC converter is found capable of suppressing up to 21st harmonics in the supply current along with the power factor improvement close to unity in the wide operating range of the drive. The effect of load variation on DTCIMD is also studied to demonstrate the effectiveness of the proposed AC-DC converter
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multipulse improved power quality ac dc convertors for vector controlled induction motor drives
IEE Proceedings - Electric Power Applications, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:The paper deals with polygon autotransformer-based 12-pulse and 18-pulse AC–DC convertors feeding vector-controlled induction-motor drives (VCIMDs) for improving power quality at the point of common coupling (PCC). The design of Autotransformers is carried out for proposed AC–DC convertors to make them suitable for retrofit applications, where at present a six-pulse diode bridge is used. The effect of load variation on VCIMD is also studied to demonstrate the effectiveness of proposed AC–DC convertors over a wide operating range. Laboratory prototypes of proposed autotransformer-based 12-pulse and 18-pulse AC–DC convertors are developed and test results are presented to validate the proposed design and model developed of the system.
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Pulse multiplication in AC-DC converters for harmonic mitigation in vector-controlled induction motor drives
IEEE Transactions on Energy Conversion, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. Garg, Sanjay GairolaAbstract:In this paper, an autotransformer with reduced kilovoltampere rating for 24-pulse ac-dc converter fed vector controlled induction motor drives (VCIMDs) is presented for harmonic current reduction. The 24-pulse operation is achieved using dc ripple reinjection technique in 12-pulse ac-dc converters. The proposed novel harmonic mitigator is found capable of suppressing up to 21st harmonic in the supply current. The procedure for the design of autotransformer for proposed ac-dc converter is presented to show the flexibility in the design for making it a cost-effective replacement suitable for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The effect of load variation on VCIMD is also studied to demonstrate the effectiveness of the proposed ac-dc converter. A set of power quality indices on input ac mains and on dc bus for a VCIMD fed from other 24-pulse ac-dc converters are also given to compare their performance. The laboratory prototypes of proposed Autotransformers based 12-pulse and 24-pulse ac-dc converters are developed and test results are presented to validate the developed design procedure and the simulation models of these ac-dc converters under varying loads.
Bhim Singh - One of the best experts on this subject based on the ideXlab platform.
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a novel polygon based 18 pulse ac dc converter for vector controlled induction motor drives
IEEE Transactions on Power Electronics, 2007Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper presents a novel configuration of an autotransformer based 18-pulse ac-dc converter for improving the power quality at the point of common coupling (PCC) in variable frequency induction motor drives (VFIMDs). The polygon based connection of autotransformer for achieving 18-pulse rectification is utilized to result in reduction in rating of the magnetics. The design of the autotransformer is carried out for an 18-pulse ac-dc converter feeding a vector controlled induction motor drive (VCIMD). Moreover, the autotransformer design is modified for making it suitable for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The effect of load variation on VCIMD is also studied and the performance of the proposed 18-pulse ac-dc converter is compared in terms of different power quality indices on both ac as well as dc side with other ac-dc converters. A laboratory prototype of the proposed autotransformer based 18-pulse ac-dc converter feeding a 10-hp induction motor drive is developed to verify the design and simulated results
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Harmonic Mitigation in AC–DC Converters for Vector Controlled Induction Motor Drives
IEEE Transactions on Energy Conversion, 2007Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper deals with autotransformer-based multipulse ac--dc converters with reduced magnetics feeding vector controlled induction motor drives for improving the power quality at the point of common coupling. The proposed 12-pulse ac--dc converter-based harmonic mitigator consists of an autotransformer alongwith a passive shunt filter tuned for 11th harmonic frequency. This results in the elimination of 5th, 7th, and 11th harmonic currents. Similarly, the proposed 18-pulse ac--dc converter-based harmonic mitigator eliminates the 5th, 7th, 11th, 13th, and 17th harmonic currents, thereby improving the power quality at ac mains. The experimentation is carried out on the developed prototype of Autotransformers-based ac--dc converters. Different power quality indexes of the proposed 12-pulse and 18-pulse ac--dc converters are obtained from simulation and verified from experimental results.
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a twelve phase ac dc converter for power quality improvement in direct torque controlled induction motor drives
Conference on Industrial Electronics and Applications, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper presents the design and analysis of a star connected autotransformer based twelve-phase AC-DC converter for improving power quality at the point of common coupling (PCC) in direct torque controlled induction motor drives (DTCIMDs). A star connected autotransformer with five windings per phase is used to realize the twelve-phase AC-DC converter. The basic design equations are derived to calculate the number of turns in different windings for achieving harmonic reduction in the proposed autotransformer based AC-DC converter. The designed twelve-phase AC-DC converter is found capable of suppressing up to 21st harmonics in the supply current along with the power factor improvement close to unity in the wide operating range of the drive. The effect of load variation on DTCIMD is also studied to demonstrate the effectiveness of the proposed AC-DC converter
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multipulse improved power quality ac dc convertors for vector controlled induction motor drives
IEE Proceedings - Electric Power Applications, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:The paper deals with polygon autotransformer-based 12-pulse and 18-pulse AC–DC convertors feeding vector-controlled induction-motor drives (VCIMDs) for improving power quality at the point of common coupling (PCC). The design of Autotransformers is carried out for proposed AC–DC convertors to make them suitable for retrofit applications, where at present a six-pulse diode bridge is used. The effect of load variation on VCIMD is also studied to demonstrate the effectiveness of proposed AC–DC convertors over a wide operating range. Laboratory prototypes of proposed autotransformer-based 12-pulse and 18-pulse AC–DC convertors are developed and test results are presented to validate the proposed design and model developed of the system.
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Pulse multiplication in AC-DC converters for harmonic mitigation in vector-controlled induction motor drives
IEEE Transactions on Energy Conversion, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. Garg, Sanjay GairolaAbstract:In this paper, an autotransformer with reduced kilovoltampere rating for 24-pulse ac-dc converter fed vector controlled induction motor drives (VCIMDs) is presented for harmonic current reduction. The 24-pulse operation is achieved using dc ripple reinjection technique in 12-pulse ac-dc converters. The proposed novel harmonic mitigator is found capable of suppressing up to 21st harmonic in the supply current. The procedure for the design of autotransformer for proposed ac-dc converter is presented to show the flexibility in the design for making it a cost-effective replacement suitable for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The effect of load variation on VCIMD is also studied to demonstrate the effectiveness of the proposed ac-dc converter. A set of power quality indices on input ac mains and on dc bus for a VCIMD fed from other 24-pulse ac-dc converters are also given to compare their performance. The laboratory prototypes of proposed Autotransformers based 12-pulse and 24-pulse ac-dc converters are developed and test results are presented to validate the developed design procedure and the simulation models of these ac-dc converters under varying loads.
G. Bhuvaneswari - One of the best experts on this subject based on the ideXlab platform.
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a novel polygon based 18 pulse ac dc converter for vector controlled induction motor drives
IEEE Transactions on Power Electronics, 2007Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper presents a novel configuration of an autotransformer based 18-pulse ac-dc converter for improving the power quality at the point of common coupling (PCC) in variable frequency induction motor drives (VFIMDs). The polygon based connection of autotransformer for achieving 18-pulse rectification is utilized to result in reduction in rating of the magnetics. The design of the autotransformer is carried out for an 18-pulse ac-dc converter feeding a vector controlled induction motor drive (VCIMD). Moreover, the autotransformer design is modified for making it suitable for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The effect of load variation on VCIMD is also studied and the performance of the proposed 18-pulse ac-dc converter is compared in terms of different power quality indices on both ac as well as dc side with other ac-dc converters. A laboratory prototype of the proposed autotransformer based 18-pulse ac-dc converter feeding a 10-hp induction motor drive is developed to verify the design and simulated results
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Harmonic Mitigation in AC–DC Converters for Vector Controlled Induction Motor Drives
IEEE Transactions on Energy Conversion, 2007Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper deals with autotransformer-based multipulse ac--dc converters with reduced magnetics feeding vector controlled induction motor drives for improving the power quality at the point of common coupling. The proposed 12-pulse ac--dc converter-based harmonic mitigator consists of an autotransformer alongwith a passive shunt filter tuned for 11th harmonic frequency. This results in the elimination of 5th, 7th, and 11th harmonic currents. Similarly, the proposed 18-pulse ac--dc converter-based harmonic mitigator eliminates the 5th, 7th, 11th, 13th, and 17th harmonic currents, thereby improving the power quality at ac mains. The experimentation is carried out on the developed prototype of Autotransformers-based ac--dc converters. Different power quality indexes of the proposed 12-pulse and 18-pulse ac--dc converters are obtained from simulation and verified from experimental results.
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a twelve phase ac dc converter for power quality improvement in direct torque controlled induction motor drives
Conference on Industrial Electronics and Applications, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:This paper presents the design and analysis of a star connected autotransformer based twelve-phase AC-DC converter for improving power quality at the point of common coupling (PCC) in direct torque controlled induction motor drives (DTCIMDs). A star connected autotransformer with five windings per phase is used to realize the twelve-phase AC-DC converter. The basic design equations are derived to calculate the number of turns in different windings for achieving harmonic reduction in the proposed autotransformer based AC-DC converter. The designed twelve-phase AC-DC converter is found capable of suppressing up to 21st harmonics in the supply current along with the power factor improvement close to unity in the wide operating range of the drive. The effect of load variation on DTCIMD is also studied to demonstrate the effectiveness of the proposed AC-DC converter
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multipulse improved power quality ac dc convertors for vector controlled induction motor drives
IEE Proceedings - Electric Power Applications, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. GargAbstract:The paper deals with polygon autotransformer-based 12-pulse and 18-pulse AC–DC convertors feeding vector-controlled induction-motor drives (VCIMDs) for improving power quality at the point of common coupling (PCC). The design of Autotransformers is carried out for proposed AC–DC convertors to make them suitable for retrofit applications, where at present a six-pulse diode bridge is used. The effect of load variation on VCIMD is also studied to demonstrate the effectiveness of proposed AC–DC convertors over a wide operating range. Laboratory prototypes of proposed autotransformer-based 12-pulse and 18-pulse AC–DC convertors are developed and test results are presented to validate the proposed design and model developed of the system.
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Pulse multiplication in AC-DC converters for harmonic mitigation in vector-controlled induction motor drives
IEEE Transactions on Energy Conversion, 2006Co-Authors: Bhim Singh, G. Bhuvaneswari, V. Garg, Sanjay GairolaAbstract:In this paper, an autotransformer with reduced kilovoltampere rating for 24-pulse ac-dc converter fed vector controlled induction motor drives (VCIMDs) is presented for harmonic current reduction. The 24-pulse operation is achieved using dc ripple reinjection technique in 12-pulse ac-dc converters. The proposed novel harmonic mitigator is found capable of suppressing up to 21st harmonic in the supply current. The procedure for the design of autotransformer for proposed ac-dc converter is presented to show the flexibility in the design for making it a cost-effective replacement suitable for retrofit applications, where presently a 6-pulse diode bridge rectifier is used. The effect of load variation on VCIMD is also studied to demonstrate the effectiveness of the proposed ac-dc converter. A set of power quality indices on input ac mains and on dc bus for a VCIMD fed from other 24-pulse ac-dc converters are also given to compare their performance. The laboratory prototypes of proposed Autotransformers based 12-pulse and 24-pulse ac-dc converters are developed and test results are presented to validate the developed design procedure and the simulation models of these ac-dc converters under varying loads.
Fred C. Lee - One of the best experts on this subject based on the ideXlab platform.
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A Family of Buck-Type DC-DC Converters with
2014Co-Authors: Kaiwei Yao, Yuancheng Ren, Jia Wei, Fred C. LeeAbstract:Abstract — This paper introduces a family of buck-type DC-DC converters with Autotransformers, including forward, push-pull, half-bridge, and full-bridge topologies. Compared with an isolated transformer, the autotransformer has a simpler winding structure, and it only needs to transfer part of the input power, resulting in a smaller secondary winding current. Analysis shows that the autotransformer can also help to reduce the voltage stress and current ratings of power devices in the DC-DC converters. For some applications, a simple lossless passive clamp circuit can be implemented to solve the transformer leakage problems, and the gate drive is significantly improved with a simple self-adaptive dead-time-controlled bootstrap gate driver. Simulation and experimental results show that the proposed topologies are very suitable for high-frequency applications. Keywords-DC-DC converter; autotransformer I
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A family of buck-type DC-DC converters with Autotransformers
Eighteenth Annual IEEE Applied Power Electronics Conference and Exposition 2003. APEC '03., 1Co-Authors: Kaiwei Yao, Yuancheng Ren, Jia Wei, Fred C. LeeAbstract:This paper introduces a family of buck-type DC-DC converters with Autotransformers, including forward, push-pull, half-bridge, and full-bridge topologies. Compared with an isolated transformer, the autotransformer has a simpler winding structure, and it only needs to transfer part of the input power, resulting in a smaller secondary winding current. Analysis shows that the autotransformer can also help to reduce the voltage stress and current ratings of power devices in the DC-DC converters. For some applications, a simple lossless passive clamp circuit can be implemented to solve the transformer leakage problems, and the gate drive is significantly improved with a simple self-adaptive dead-time-controlled bootstrap gate driver. Simulation and experimental results show that the proposed topologies are very suitable for high-frequency applications.
Shiyan Yang - One of the best experts on this subject based on the ideXlab platform.
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Optimal design of star-connected autotransformer applied to large current rectifier
IET Electric Power Applications, 2017Co-Authors: Fangang Meng, Lei Gao, Wei Yang, Liu Pengyu, Shiyan YangAbstract:To improve the power density of large current rectifier, this study designs optimally a star-connected autotransformer which is used in large current rectifier. From the viewpoint of minimising the kVA rating of phase-shift transformer and conduction loss of rectification devices, it is concluded that the ideal large current rectifier is a combination of dual three-phase half-wave rectifiers and a star-connected autotransformer which is used to be the phase-shift transformer. To design optimally the star-connected autotransformer, the winding configurations of the star-connected autotransformer are analysed, and the corresponding expressions and waveforms of current through windings at different winding configurations are also obtained. Consequently, the kVA rating expressions of the autotransformer under different winding configurations are calculated, which describe the relationship between the winding configuration and load power. From the expressions, the optimal winding configuration, which has the least kVA rating and winding numbers, is obtained. Some simulations and experiments are carried out to verify the theoretical analysis.
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Comprehensive comparison of the delta- and wye-connected autotransformer applied to 12-pulse rectifier
Journal of Modern Power Systems and Clean Energy, 2016Co-Authors: Fangang Meng, Lei Gao, Wei Yang, Shiyan YangAbstract:12-pulse rectifier is extensively used in high power rectification, and the delta-connected autotransformer and wye-connected autotransformer are its two most popular phase-shift transformers. This paper compares the 12-pulse rectifiers using the two transformers via calculating the input line current, load voltage, kVA ratings of the two autotransformer, kVA ratings of the auxiliary magnetic devices. From the viewpoint of power quality of AC mains and DC side, the two 12-pulse rectifiers are the same. The kVA rating of the IPR in the two 12-pulse rectifiers are equal, and the kVA rating of the ZSBT in the two 12-pulse rectifier are also equal to each other, under the same load power. However, the kVA of the delta-connected autotransformer is less than that of the wye-connected autotransformer under the same load power. Some experimental results are shown to validate the correctness of the theoretical analysis.
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effect of phase shift angle on a delta connected autotransformer applied to a 12 pulse rectifier
IEEE Transactions on Industrial Electronics, 2015Co-Authors: Fangang Meng, Lei Gao, Shiyan Yang, Wei YangAbstract:The delta-connected autotransformer with $\pi/6$ phase-shift angle is widely used in the multipulse rectifier when the output voltage of the autotransformer is approximately equal to its input voltage. If its output voltage is slightly greater than its input voltage, the equivalent kilovoltampere (kVA) rating of the autotransformer increases rapidly, and each core limb of the autotransformer has five windings. The increase in winding number will increase the asymmetry and manufacture difficulty of the autotransformer. Therefore, the autotransformer with $\pi/6$ phase-shift angle is not suitable in the boost voltage application. This paper analyzes the effect of phase-shift angle of the autotransformer with three windings in each core limb on the input line current, output voltage, and equivalent kVA rating and proposes a new phase-shift angle. The equivalent kVA rating of the delta-connected autotransformer with the new phase-shift angle is slightly greater than that of the autotransformer with $\pi/6$ phase-shift angle under the same turn ratio, but the autotransformer with the new phase-shift angle has three windings in each core limb and is propitious to design and manufacture. Some simulation and experiment are carried out to verify the theoretical analysis.
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effect of voltage transformation ratio on the kilovoltampere rating of delta connected autotransformer for 12 pulse rectifier system
IEEE Transactions on Industrial Electronics, 2013Co-Authors: Fangang Meng, Wei Yang, Shiyan YangAbstract:This paper presents the effect of voltage transformation ratio on the kilovoltampere rating of delta-connected autotransformer for 12-pulse rectifier system and gives an optimal configuration of the autotransformer with minimal kilovoltampere rating and the least windings. According to the phasor diagrams and the relation between the output voltage and input voltage of the autotransformer under different connection ways, the effect of voltage transformation ratio on current through windings is analyzed, and corresponding expressions and waveforms of the currents are also obtained. Consequently, a relation between the position parameter and output power is established, and based on the relation, the effect of winding configuration on the kilovoltampere rating of the autotransformer is analyzed, which can be used to obtain the optimal configuration. From the theoretical analysis, an autotransformer with optimal configuration and minimal equivalent kilovoltampere rating is designed. Some simulated and experimental results show the correctness of the theoretical analysis.