The Experts below are selected from a list of 246 Experts worldwide ranked by ideXlab platform
Urban Lundin - One of the best experts on this subject based on the ideXlab platform.
-
Comparison of Thyristor Rectifier Configurations for a Six-Phase Rotating Brushless Outer Pole PM Exciter
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Jonas Kristiansen Noland, Fredrik Evestedt, J. José Pérez-loya, Johan Abrahamsson, Urban LundinAbstract:Recent technological developments have caused a renewed interest in the brushless excitation system. With the application of wireless communication, the conventional diode bridge has been replaced with fully controllable Thyristors on the shaft. It offers the same dynamic performance as the conventional static excitation system. The Thyristor bridge of the conventional three-phase exciter needs to be controlled with a high firing angle in normal operation in order to fulfill a requirement of both a high ceiling voltage and a high ceiling current. A high firing angle causes high torque ripple to be absorbed by the exciter stator and a low power factor results in a low utilization of the designed exciter. In this contribution, we present a strategy that solves this problem by looking into combinations of Thyristor configurations of a double-star six-phase connection of the exciter. Experimental results are used to verify the circuit models implemented for this investigation. A hybrid-mode 12-pulse Thyristor bridge configuration seems to be a good solution for implementations in commercial apparatus. An additional switch interconnects two separate Thyristor bridges from parallel- to series connection at the rectifier output, and utilizes the advantages of both topologies.
-
Design and Characterization of a Rotating Brushless Outer Pole PM Exciter for a Synchronous Generator
IEEE Transactions on Industry Applications, 2017Co-Authors: Jonas Kristiansen Noland, Fredrik Evestedt, J. José Pérez-loya, Johan Abrahamsson, Urban LundinAbstract:IEEE Recent technological developments have caused a renewed interest in the brushless excitation system. With the application of wireless communication, the conventional diode bridge has been replaced with fully controllable Thyristors on the shaft. It offers the same dynamic performance as the conventional static excitation system. The Thyristor bridge of the conventional three-phase exciter needs to be controlled with a high firing angle in normal operation in order to fulfill a requirement of both a high ceiling voltage and a high ceiling current. A high firing angle causes high torque ripple to be absorbed by the exciter stator and a low power factor results in a low utilization of the designed exciter. In this contribution we present a strategy that solves this problem by looking into combinations of Thyristor configurations of a double-star six-phase connection of the exciter. Experimental results are used to verify the circuit models implemented for this investigation. A hybrid-mode 12-pulse Thyristor bridge configuration seems to be a good solution for implementations in commercial apparatus. An additional switch interconnects two separate Thyristor bridges from parallel- to series-connection at the rectifier output, and utilizes the advantages of both topologies.
Jonas Kristiansen Noland - One of the best experts on this subject based on the ideXlab platform.
-
Comparison of Thyristor Rectifier Configurations for a Six-Phase Rotating Brushless Outer Pole PM Exciter
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Jonas Kristiansen Noland, Fredrik Evestedt, J. José Pérez-loya, Johan Abrahamsson, Urban LundinAbstract:Recent technological developments have caused a renewed interest in the brushless excitation system. With the application of wireless communication, the conventional diode bridge has been replaced with fully controllable Thyristors on the shaft. It offers the same dynamic performance as the conventional static excitation system. The Thyristor bridge of the conventional three-phase exciter needs to be controlled with a high firing angle in normal operation in order to fulfill a requirement of both a high ceiling voltage and a high ceiling current. A high firing angle causes high torque ripple to be absorbed by the exciter stator and a low power factor results in a low utilization of the designed exciter. In this contribution, we present a strategy that solves this problem by looking into combinations of Thyristor configurations of a double-star six-phase connection of the exciter. Experimental results are used to verify the circuit models implemented for this investigation. A hybrid-mode 12-pulse Thyristor bridge configuration seems to be a good solution for implementations in commercial apparatus. An additional switch interconnects two separate Thyristor bridges from parallel- to series connection at the rectifier output, and utilizes the advantages of both topologies.
-
Design and Characterization of a Rotating Brushless Outer Pole PM Exciter for a Synchronous Generator
IEEE Transactions on Industry Applications, 2017Co-Authors: Jonas Kristiansen Noland, Fredrik Evestedt, J. José Pérez-loya, Johan Abrahamsson, Urban LundinAbstract:IEEE Recent technological developments have caused a renewed interest in the brushless excitation system. With the application of wireless communication, the conventional diode bridge has been replaced with fully controllable Thyristors on the shaft. It offers the same dynamic performance as the conventional static excitation system. The Thyristor bridge of the conventional three-phase exciter needs to be controlled with a high firing angle in normal operation in order to fulfill a requirement of both a high ceiling voltage and a high ceiling current. A high firing angle causes high torque ripple to be absorbed by the exciter stator and a low power factor results in a low utilization of the designed exciter. In this contribution we present a strategy that solves this problem by looking into combinations of Thyristor configurations of a double-star six-phase connection of the exciter. Experimental results are used to verify the circuit models implemented for this investigation. A hybrid-mode 12-pulse Thyristor bridge configuration seems to be a good solution for implementations in commercial apparatus. An additional switch interconnects two separate Thyristor bridges from parallel- to series-connection at the rectifier output, and utilizes the advantages of both topologies.
S. Tsyranov - One of the best experts on this subject based on the ideXlab platform.
-
High current and current rise rate Thyristor based switches
2017 IEEE 21st International Conference on Pulsed Power (PPC), 2017Co-Authors: A. Gusev, S. Lyubutin, A. Ponomarev, S. Rukin, B. Slovikovsky, S. TsyranovAbstract:Operation of the Thyristor-based switches triggered in impact-ionization wave mode has been investigated. The Thyristor switch contained two series connected tablet Thyristors having a silicon wafer of 56 mm in diameter. At applying across the switch a triggering pulse with a voltage rise rate dU/dt of over 1 kV/ns the Thyristors transition time to conductive state was less than 1 ns. It is shown that the maximum amplitude of no-failure current is increased with increasing dU/dt at the triggering stage. A possible mechanism of the dU/dt value effect on the Thyristors breakdown current is discussed. In safety operation regime at dU/dt = 6 kV/ns (3 kV/ns per a single Thyristor) the switch discharged 1-mF capacitor, which was charged to a voltage of 5 kV, to a resistive load of 18 mΩ. The following results were obtained: a peak current was 200 kA, an initial dI/dt was 58 kA/ps, a FWHM was 25 ps, and switching efficiency was 0.97. It is shown that a temperature of the silicon wafer is one of the main factors that affects on the Thyristor switching process. Results of the Thyristors testing in pulse repetition mode are given also.
-
superfast Thyristor based switches operating in impact ionization wave mode
IEEE Transactions on Plasma Science, 2016Co-Authors: Anton I. Gusev, S. Lyubutin, S. Rukin, S. TsyranovAbstract:The process of triggering Thyristors by an overvoltage pulse with a short rise time was investigated. Low-frequency commercial Thyristors of tablet design with diameters of silicon wafers of 32–56 mm and an operating voltage of 2–2.4 kV dc were used in the experiments. An external overvoltage pulse was applied across the Thyristor main electrodes, which ensured a voltage rise rate from 0.5 to 6 kV/ns within a few nanoseconds. Under such conditions, the Thyristor closing process occurred due to initiation and propagation of a fast ionization front across the semiconductor structure. The time of switching the Thyristor from the blocking state to the conducting state was within 200–400 ps. The Thyristor-based switches operated in this mode were tested in two discharge circuits. In the first circuit, an assembly of nine 2-kV and 40-mm Thyristors connected in series switched a 2- $\mu \text{F}$ capacitor, which was charged to a voltage of 20 kV and to a resistive load of $0.17~\Omega $ . The following results were obtained: discharge current amplitude of 45 kA, maximum current-rise rate of 134 kA/ $\mu \text{s}$ , current rise time (0.1–0.9 level) of $\sim 0.4~\mu \text{s}$ , pulse duration (FWHM) of $\sim 1~\mu \text{s}$ , and switching efficiency of 0.85. In the second circuit, the switch contained two 2.4-kV and 56-mm Thyristors connected in series. A 400- $\mu \text{F}$ capacitor, which was charged to a voltage of 5 kV, was switched to a resistive load of $0.026~\Omega $ . The following discharge parameters were obtained: discharge current amplitude of 114 kA, maximum current-rise rate of 32 kA/ $\mu \text{s}$ , current rise time (0.1–0.9 level) of $\sim 5~\mu \text{s}$ , pulse duration (FWHM) of $\sim 20~\mu \text{s}$ , and switching efficiency of 0.96.
-
High power Thyristors triggering providing a subnanosecond closing time
2014 IEEE International Power Modulator and High Voltage Conference (IPMHVC), 2014Co-Authors: Anton I. Gusev, S. Lyubutin, S. Rukin, S. TsyranovAbstract:A possibility of fast subnanosecond triggering of commercial low-frequency Thyristors has been investigated. In experiments low dI/dt (100-400 A/μs) tablet Thyristors having a silicon wafer of 32 to 40 mm in diameter and 2 kV DC operating voltage were used. For the Thyristor triggering a fast subnanosecond pulse was applied across its main electrodes. During the switching process the voltage across 2-kV DC Thyristor increased from 2 to 5-8 kV in about 0.8-1 ns, and then dropped in about 200 ps. Under such conditions the Thyristor closing process occurred due to initiation and propagation of fast ionization front across the semiconductor structure. A stack of 6 Thyristors connected in series operated at 13-kV charging voltage and switched 2-μF capacitor bank into resistive load of 0.25 Ω. At total circuit inductance of ~100 nH the following discharge parameters were obtained: a peak current was 27.6 kA, dI/dt was 113 kA/μs, FWHM was ~1 μs, and a peak power in the load was 190 MW.
Fredrik Evestedt - One of the best experts on this subject based on the ideXlab platform.
-
Comparison of Thyristor Rectifier Configurations for a Six-Phase Rotating Brushless Outer Pole PM Exciter
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Jonas Kristiansen Noland, Fredrik Evestedt, J. José Pérez-loya, Johan Abrahamsson, Urban LundinAbstract:Recent technological developments have caused a renewed interest in the brushless excitation system. With the application of wireless communication, the conventional diode bridge has been replaced with fully controllable Thyristors on the shaft. It offers the same dynamic performance as the conventional static excitation system. The Thyristor bridge of the conventional three-phase exciter needs to be controlled with a high firing angle in normal operation in order to fulfill a requirement of both a high ceiling voltage and a high ceiling current. A high firing angle causes high torque ripple to be absorbed by the exciter stator and a low power factor results in a low utilization of the designed exciter. In this contribution, we present a strategy that solves this problem by looking into combinations of Thyristor configurations of a double-star six-phase connection of the exciter. Experimental results are used to verify the circuit models implemented for this investigation. A hybrid-mode 12-pulse Thyristor bridge configuration seems to be a good solution for implementations in commercial apparatus. An additional switch interconnects two separate Thyristor bridges from parallel- to series connection at the rectifier output, and utilizes the advantages of both topologies.
-
Design and Characterization of a Rotating Brushless Outer Pole PM Exciter for a Synchronous Generator
IEEE Transactions on Industry Applications, 2017Co-Authors: Jonas Kristiansen Noland, Fredrik Evestedt, J. José Pérez-loya, Johan Abrahamsson, Urban LundinAbstract:IEEE Recent technological developments have caused a renewed interest in the brushless excitation system. With the application of wireless communication, the conventional diode bridge has been replaced with fully controllable Thyristors on the shaft. It offers the same dynamic performance as the conventional static excitation system. The Thyristor bridge of the conventional three-phase exciter needs to be controlled with a high firing angle in normal operation in order to fulfill a requirement of both a high ceiling voltage and a high ceiling current. A high firing angle causes high torque ripple to be absorbed by the exciter stator and a low power factor results in a low utilization of the designed exciter. In this contribution we present a strategy that solves this problem by looking into combinations of Thyristor configurations of a double-star six-phase connection of the exciter. Experimental results are used to verify the circuit models implemented for this investigation. A hybrid-mode 12-pulse Thyristor bridge configuration seems to be a good solution for implementations in commercial apparatus. An additional switch interconnects two separate Thyristor bridges from parallel- to series-connection at the rectifier output, and utilizes the advantages of both topologies.
J. José Pérez-loya - One of the best experts on this subject based on the ideXlab platform.
-
Comparison of Thyristor Rectifier Configurations for a Six-Phase Rotating Brushless Outer Pole PM Exciter
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Jonas Kristiansen Noland, Fredrik Evestedt, J. José Pérez-loya, Johan Abrahamsson, Urban LundinAbstract:Recent technological developments have caused a renewed interest in the brushless excitation system. With the application of wireless communication, the conventional diode bridge has been replaced with fully controllable Thyristors on the shaft. It offers the same dynamic performance as the conventional static excitation system. The Thyristor bridge of the conventional three-phase exciter needs to be controlled with a high firing angle in normal operation in order to fulfill a requirement of both a high ceiling voltage and a high ceiling current. A high firing angle causes high torque ripple to be absorbed by the exciter stator and a low power factor results in a low utilization of the designed exciter. In this contribution, we present a strategy that solves this problem by looking into combinations of Thyristor configurations of a double-star six-phase connection of the exciter. Experimental results are used to verify the circuit models implemented for this investigation. A hybrid-mode 12-pulse Thyristor bridge configuration seems to be a good solution for implementations in commercial apparatus. An additional switch interconnects two separate Thyristor bridges from parallel- to series connection at the rectifier output, and utilizes the advantages of both topologies.
-
Design and Characterization of a Rotating Brushless Outer Pole PM Exciter for a Synchronous Generator
IEEE Transactions on Industry Applications, 2017Co-Authors: Jonas Kristiansen Noland, Fredrik Evestedt, J. José Pérez-loya, Johan Abrahamsson, Urban LundinAbstract:IEEE Recent technological developments have caused a renewed interest in the brushless excitation system. With the application of wireless communication, the conventional diode bridge has been replaced with fully controllable Thyristors on the shaft. It offers the same dynamic performance as the conventional static excitation system. The Thyristor bridge of the conventional three-phase exciter needs to be controlled with a high firing angle in normal operation in order to fulfill a requirement of both a high ceiling voltage and a high ceiling current. A high firing angle causes high torque ripple to be absorbed by the exciter stator and a low power factor results in a low utilization of the designed exciter. In this contribution we present a strategy that solves this problem by looking into combinations of Thyristor configurations of a double-star six-phase connection of the exciter. Experimental results are used to verify the circuit models implemented for this investigation. A hybrid-mode 12-pulse Thyristor bridge configuration seems to be a good solution for implementations in commercial apparatus. An additional switch interconnects two separate Thyristor bridges from parallel- to series-connection at the rectifier output, and utilizes the advantages of both topologies.
