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Yuzhi Zhou - One of the best experts on this subject based on the ideXlab platform.

  • impActs of three mmc hvdc configurations on Ac system stability under dc line faults
    Power and Energy Society General Meeting, 2015
    Co-Authors: Geng Tang, Yuzhi Zhou
    Abstract:

    This paper analyzes the dc line fault transient stability charActeristics of Ac/DC power systems based on three different modular multilevel converter based high power direct current (MMC-HVDC) configurations. The first configuration is half bridge sub-module based MMC (H-MMC) HVDC configuration, which clears dc line faults by tripping the Ac Circuit breakers. Voltage source converters (VSC) with dc line fault clearance ability constitute the second configuration. A line-commutated convener (LCC) and MMC hybrid HVDC configuration with dc line fault clearance ability, named LCC-diode-MMC (LCC-D-MMC), is the third configuration. The detailed processes of clearing dc line faults in three MMC-HVDC configurations are analyzed. The equal area criterion is utilized to analyze the dc line fault transient processes. Besides, to evaluate the power system transient stability charActeristics in three MMC-HVDC configurations, an index, called critical Ac transmitted power (PAc_critical), is proposed. Under the same dc line to ground fault, transient stability charActeristics of three test systems based on the three different MMC-HVDC configurations are compared. Excellent performances of the LCC-D-MMC HVDC system under the dc line fault are demonstrated through comparison of PAc_critical in the three test systems. Finally, the study is extended to a modified New England 39 bus system, and the simulation results also tally with the theoretical analysis.

  • ImpActs of three MMC-HVDC configurations on Ac system stability under DC line faults
    IEEE Transactions on Power Systems, 2014
    Co-Authors: Geng Tang, Zheng Xu, Yuzhi Zhou
    Abstract:

    This paper analyzes the dc line fault transient stability charActeristics of Ac/DC power systems with three different modular multilevel converter based high voltage direct current (MMC-HVDC) configurations. The first configuration is half bridge sub-module based MMC (H-MMC) HVDC configuration, which clears dc line faults by tripping the Ac Circuit breakers. The clamp double sub-module (CDSM) based MMC (C-MMC) HVDC configuration with dc line fault clearance ability constitutes the second configuration. A line-commutated converter (LCC) and MMC hybrid HVDC configuration with dc line fault clearance ability, named LCC-diode-MMC (LCC-D-MMC), is the third configuration. The detailed processes of clearing dc line faults in three MMC-HVDC configurations are analyzed. The equal area criterion is utilized to analyze the dc line fault transient processes. Besides, to evaluate the power system transient stability charActeristics in three MMC-HVDC configurations, an index, called critical Ac transmitted power $(P_{Ac_critical})$ , is proposed. Under the same dc line to ground fault, transient stability charActeristics of three test systems based on the three different MMC-HVDC configurations are compared. Excellent performance of the LCC-D-MMC HVDC configuration under the dc line fault is demonstrated through comparison of $P_{Ac_critical}$ in the three test systems. Finally, the study is extended to a modified New England 39-bus system, and the simulation results also correspond with the theoretical analysis.

Geng Tang - One of the best experts on this subject based on the ideXlab platform.

  • impActs of three mmc hvdc configurations on Ac system stability under dc line faults
    Power and Energy Society General Meeting, 2015
    Co-Authors: Geng Tang, Yuzhi Zhou
    Abstract:

    This paper analyzes the dc line fault transient stability charActeristics of Ac/DC power systems based on three different modular multilevel converter based high power direct current (MMC-HVDC) configurations. The first configuration is half bridge sub-module based MMC (H-MMC) HVDC configuration, which clears dc line faults by tripping the Ac Circuit breakers. Voltage source converters (VSC) with dc line fault clearance ability constitute the second configuration. A line-commutated convener (LCC) and MMC hybrid HVDC configuration with dc line fault clearance ability, named LCC-diode-MMC (LCC-D-MMC), is the third configuration. The detailed processes of clearing dc line faults in three MMC-HVDC configurations are analyzed. The equal area criterion is utilized to analyze the dc line fault transient processes. Besides, to evaluate the power system transient stability charActeristics in three MMC-HVDC configurations, an index, called critical Ac transmitted power (PAc_critical), is proposed. Under the same dc line to ground fault, transient stability charActeristics of three test systems based on the three different MMC-HVDC configurations are compared. Excellent performances of the LCC-D-MMC HVDC system under the dc line fault are demonstrated through comparison of PAc_critical in the three test systems. Finally, the study is extended to a modified New England 39 bus system, and the simulation results also tally with the theoretical analysis.

  • ImpActs of three MMC-HVDC configurations on Ac system stability under DC line faults
    IEEE Transactions on Power Systems, 2014
    Co-Authors: Geng Tang, Zheng Xu, Yuzhi Zhou
    Abstract:

    This paper analyzes the dc line fault transient stability charActeristics of Ac/DC power systems with three different modular multilevel converter based high voltage direct current (MMC-HVDC) configurations. The first configuration is half bridge sub-module based MMC (H-MMC) HVDC configuration, which clears dc line faults by tripping the Ac Circuit breakers. The clamp double sub-module (CDSM) based MMC (C-MMC) HVDC configuration with dc line fault clearance ability constitutes the second configuration. A line-commutated converter (LCC) and MMC hybrid HVDC configuration with dc line fault clearance ability, named LCC-diode-MMC (LCC-D-MMC), is the third configuration. The detailed processes of clearing dc line faults in three MMC-HVDC configurations are analyzed. The equal area criterion is utilized to analyze the dc line fault transient processes. Besides, to evaluate the power system transient stability charActeristics in three MMC-HVDC configurations, an index, called critical Ac transmitted power $(P_{Ac_critical})$ , is proposed. Under the same dc line to ground fault, transient stability charActeristics of three test systems based on the three different MMC-HVDC configurations are compared. Excellent performance of the LCC-D-MMC HVDC configuration under the dc line fault is demonstrated through comparison of $P_{Ac_critical}$ in the three test systems. Finally, the study is extended to a modified New England 39-bus system, and the simulation results also correspond with the theoretical analysis.

Roger Briggs - One of the best experts on this subject based on the ideXlab platform.

  • Active damping of ultrafast mechanical switches for hybrid Ac and dc Circuit breakers
    IEEE Transactions on Industry Applications, 2017
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Landon Mackey, Wensong Yu, Roger Briggs
    Abstract:

    An Active damping method for Thomson coil Actuated ultrafast mechanical switches is proposed, including its control. Ultrafast mechanical switches are crucial for both dc and Ac Circuit breakers that require fast-Acting current-limiting capabilities. However, fast motion means high velocity at the end of travel resulting in over-travel, bounce, fatigue, and other undesirable effects. The Active damping proposed in this paper not only avoids such issues but Actually enables faster travel by removing limitations that would otherwise be necessary. This Active damping mechanism is applicable in particular to medium- and high-voltage Circuit breakers, but can be extended to Actuators in general. A 15 kV/630 A/1 ms mechanical switch designed to enable the fast protection of medium voltage dc Circuits is used as a testbed for the concept. The switch is based on the principle of repulsion forces (Thomson coil Actuator). By energizing a second coil, higher opening speeds can be damped, resulting in limited over-travel range of the movable contAct. The overall structure is simple and the size of the overall switch is minimized. To validate the concept and to study the timing control for best Active damping performance, both finite element modeling and experimental studies have been carried out.

  • Active damping of ultra fast mechanical switches for hybrid Ac and dc Circuit breakers
    European Conference on Cognitive Ergonomics, 2016
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Landon Mackey, Roger Briggs
    Abstract:

    An Active damping method for Thomson coil Actuated ultra-fast mechanical switches is proposed, including its control. Ultra fast mechanical switches are crucial for both DC and Ac Circuit breakers that require fast-Acting, current-limiting capabilities. However, fast motion means high velocity at the end of travel, resulting in over-travel, bounce, fatigue, and other undesirable effects. The Active damping proposed in this paper not only avoids such issues, but Actually enables faster travel by removing limitations that would otherwise be necessary. This Active damping mechanism is applicable in particular to medium and high voltage Circuit breakers, but can be extended to Actuators in general. A 15kV/630A/1ms mechanical switch, designed to enable the fast protection of medium voltage DC Circuits, is used as a testbed for the concept. It is based on the principle of repulsion forces (Thomson coil Actuator). By energizing a second coil, higher opening speeds can be damped with limited over-travel range of the movable contAct. The overall structure is simple, and the size of the overall switch is minimized. To validate the concept and to study the timing control for best Active damping performance, both finite element modeling and experimental studies have been carried out.

  • a fast mechanical switch for medium voltage hybrid dc and Ac Circuit breakers
    IEEE Transactions on Industry Applications, 2016
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Roger Briggs
    Abstract:

    This paper presents the design and experimental results of a Thomson coil-based fast mechanical switch for hybrid Ac and dc Circuit breakers rated at 30-kV voltage and 630-A current. The compAct design with optimized Circuit parameters and geometric dimensions of components targets 2-mm travel within 1 ms when driven by a 2-mF capAcitor bank precharged to 500 V. The use and design of a disc spring as the damping and holding mechanism is presented. Structural design of a complete switch assembly rather than just the Actuator is given. Experimental results show that the switch can travel 1.3 mm in the first 1 ms and 3.1 mm in the first 2 ms when driven by a 360-V 2-mF capAcitor bank. Such fast mechanical switches fAcilitate hybrid Circuit breaker interruptions within 2 or 3 ms for ultra-fast and highly efficient protections in 5–35 kV medium-voltage dc as well as Ac systems.

  • A Fast Mechanical Switch for Medium-Voltage Hybrid DC and Ac Circuit Breakers
    IEEE Transactions on Industry Applications, 2016
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Roger Briggs
    Abstract:

    This paper presents the design and experimental results of a Thomson coil-based fast mechanical switch for hybrid Ac and dc Circuit breakers rated at 30-kV voltage and 630-A current. The compAct design with optimized Circuit parameters and geometric dimensions of components targets 2-mm travel within 1 ms when driven by a 2-mF capAcitor bank precharged to 500 V. The use and design of a disc spring as the damping and holding mechanism is presented. Structural design of a complete switch assembly rather than just the Actuator is given. Experimental results show that the switch can travel 1.3 mm in the first 1 ms and 3.1 mm in the first 2 ms when driven by a 360-V 2-mF capAcitor bank. Such fast mechanical switches fAcilitate hybrid Circuit breaker interruptions within 2 or 3 ms for ultra-fast and highly efficient protections in 5-35 kV medium-voltage dc as well as Ac systems.

  • a fast mechanical switch for medium voltage hybrid dc and Ac Circuit breakers
    European Conference on Cognitive Ergonomics, 2015
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Roger Briggs
    Abstract:

    The paper presents the design and experimental results of a Thomson coil based fast mechanical switch for hybrid Ac and DC Circuit breakers rated at 30 kV voltage and 630 A current. The compAct design with optimized Circuit parameters and geometric dimensions of components targets 2 mm travel within 1 ms when driven by a 2 mF capAcitor bank pre-charged to 500 V. The use and design of a disc spring as the damping and holding mechanism is presented. Structural design of a complete switch assembly rather than just the Actuator is given. Experimental results show that the switch can travel 1.3 mm in the first 1 ms, and 3.1 mm in the first 2 ms when driven by a 360 V 2 mF capAcitor bank. Such fast mechanical switches fAcilitate hybrid Circuit breaker interruptions within 2 or 3 milliseconds for ultra fast and highly efficient protections in 5–35 kV medium voltage DC as well as Ac systems.

G Gattavari - One of the best experts on this subject based on the ideXlab platform.

  • design oriented steady state analysis of llc resonant converters based on fha
    International Symposium on Power Electronics Electrical Drives Automation and Motion, 2006
    Co-Authors: S De Simone, Claudio Adragna, Claudio Spini, G Gattavari
    Abstract:

    The aim of this paper is to present a comprehensive design methodology for an LLC resonant converter, based on a detailed quantitative analysis of the steady-state operation of the Circuit. This analysis follows the first harmonic approximation (FHA) approAch, which tremendously simplifies the system model, leading to a linear Circuit, which can be dealt with through the classical complex Ac-Circuit analysis. Two of the major benefits of the LLC resonant topology are the ability of the power MOSFETs and secondary rectifiers to be soft-switched and the capability of operating down to zero load. The design-oriented steady-state analysis presented in this paper addresses these two constraints quantitatively, allowing the designer to derive the Circuit parameters which not only fulfil input voltage and output power specification data but also soft-switching and no-load operation constraints

  • design oriented steady state analysis of llc resonant converters based on fha
    International Symposium on Power Electronics Electrical Drives Automation and Motion, 2006
    Co-Authors: S De Simone, Claudio Adragna, Claudio Spini, G Gattavari
    Abstract:

    The aim of this paper is to present a comprehensive design methodology for an LLC resonant converter, based on a detailed quantitative analysis of the steady-state operation of the Circuit. This analysis follows the first harmonic approximation (FHA) approAch, which tremendously simplifies the system model, leading to a linear Circuit, which can be dealt with through the classical complex Ac-Circuit analysis. Two of the major benefits of the LLC resonant topology are the ability of the power MOSFETs and secondary rectifiers to be soft-switched and the capability of operating down to zero load. The design-oriented steady-state analysis presented in this paper addresses these two constraints quantitatively, allowing the designer to derive the Circuit parameters which not only fulfil input voltage and output power specification data but also soft-switching and no-load operation constraints

Chang Peng - One of the best experts on this subject based on the ideXlab platform.

  • Active damping of ultrafast mechanical switches for hybrid Ac and dc Circuit breakers
    IEEE Transactions on Industry Applications, 2017
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Landon Mackey, Wensong Yu, Roger Briggs
    Abstract:

    An Active damping method for Thomson coil Actuated ultrafast mechanical switches is proposed, including its control. Ultrafast mechanical switches are crucial for both dc and Ac Circuit breakers that require fast-Acting current-limiting capabilities. However, fast motion means high velocity at the end of travel resulting in over-travel, bounce, fatigue, and other undesirable effects. The Active damping proposed in this paper not only avoids such issues but Actually enables faster travel by removing limitations that would otherwise be necessary. This Active damping mechanism is applicable in particular to medium- and high-voltage Circuit breakers, but can be extended to Actuators in general. A 15 kV/630 A/1 ms mechanical switch designed to enable the fast protection of medium voltage dc Circuits is used as a testbed for the concept. The switch is based on the principle of repulsion forces (Thomson coil Actuator). By energizing a second coil, higher opening speeds can be damped, resulting in limited over-travel range of the movable contAct. The overall structure is simple and the size of the overall switch is minimized. To validate the concept and to study the timing control for best Active damping performance, both finite element modeling and experimental studies have been carried out.

  • Active damping of ultra fast mechanical switches for hybrid Ac and dc Circuit breakers
    European Conference on Cognitive Ergonomics, 2016
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Landon Mackey, Roger Briggs
    Abstract:

    An Active damping method for Thomson coil Actuated ultra-fast mechanical switches is proposed, including its control. Ultra fast mechanical switches are crucial for both DC and Ac Circuit breakers that require fast-Acting, current-limiting capabilities. However, fast motion means high velocity at the end of travel, resulting in over-travel, bounce, fatigue, and other undesirable effects. The Active damping proposed in this paper not only avoids such issues, but Actually enables faster travel by removing limitations that would otherwise be necessary. This Active damping mechanism is applicable in particular to medium and high voltage Circuit breakers, but can be extended to Actuators in general. A 15kV/630A/1ms mechanical switch, designed to enable the fast protection of medium voltage DC Circuits, is used as a testbed for the concept. It is based on the principle of repulsion forces (Thomson coil Actuator). By energizing a second coil, higher opening speeds can be damped with limited over-travel range of the movable contAct. The overall structure is simple, and the size of the overall switch is minimized. To validate the concept and to study the timing control for best Active damping performance, both finite element modeling and experimental studies have been carried out.

  • a fast mechanical switch for medium voltage hybrid dc and Ac Circuit breakers
    IEEE Transactions on Industry Applications, 2016
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Roger Briggs
    Abstract:

    This paper presents the design and experimental results of a Thomson coil-based fast mechanical switch for hybrid Ac and dc Circuit breakers rated at 30-kV voltage and 630-A current. The compAct design with optimized Circuit parameters and geometric dimensions of components targets 2-mm travel within 1 ms when driven by a 2-mF capAcitor bank precharged to 500 V. The use and design of a disc spring as the damping and holding mechanism is presented. Structural design of a complete switch assembly rather than just the Actuator is given. Experimental results show that the switch can travel 1.3 mm in the first 1 ms and 3.1 mm in the first 2 ms when driven by a 360-V 2-mF capAcitor bank. Such fast mechanical switches fAcilitate hybrid Circuit breaker interruptions within 2 or 3 ms for ultra-fast and highly efficient protections in 5–35 kV medium-voltage dc as well as Ac systems.

  • A Fast Mechanical Switch for Medium-Voltage Hybrid DC and Ac Circuit Breakers
    IEEE Transactions on Industry Applications, 2016
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Roger Briggs
    Abstract:

    This paper presents the design and experimental results of a Thomson coil-based fast mechanical switch for hybrid Ac and dc Circuit breakers rated at 30-kV voltage and 630-A current. The compAct design with optimized Circuit parameters and geometric dimensions of components targets 2-mm travel within 1 ms when driven by a 2-mF capAcitor bank precharged to 500 V. The use and design of a disc spring as the damping and holding mechanism is presented. Structural design of a complete switch assembly rather than just the Actuator is given. Experimental results show that the switch can travel 1.3 mm in the first 1 ms and 3.1 mm in the first 2 ms when driven by a 360-V 2-mF capAcitor bank. Such fast mechanical switches fAcilitate hybrid Circuit breaker interruptions within 2 or 3 ms for ultra-fast and highly efficient protections in 5-35 kV medium-voltage dc as well as Ac systems.

  • a fast mechanical switch for medium voltage hybrid dc and Ac Circuit breakers
    European Conference on Cognitive Ergonomics, 2015
    Co-Authors: Chang Peng, Iqbal Husain, Alex Q Huang, Bruno Patrice Bernard Lequesne, Roger Briggs
    Abstract:

    The paper presents the design and experimental results of a Thomson coil based fast mechanical switch for hybrid Ac and DC Circuit breakers rated at 30 kV voltage and 630 A current. The compAct design with optimized Circuit parameters and geometric dimensions of components targets 2 mm travel within 1 ms when driven by a 2 mF capAcitor bank pre-charged to 500 V. The use and design of a disc spring as the damping and holding mechanism is presented. Structural design of a complete switch assembly rather than just the Actuator is given. Experimental results show that the switch can travel 1.3 mm in the first 1 ms, and 3.1 mm in the first 2 ms when driven by a 360 V 2 mF capAcitor bank. Such fast mechanical switches fAcilitate hybrid Circuit breaker interruptions within 2 or 3 milliseconds for ultra fast and highly efficient protections in 5–35 kV medium voltage DC as well as Ac systems.