EPE Association: EPE-PEMC 2000 - Topic 06e: General Section

EPE-PEMC 2000 - Topic 06e: General Section
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2000 - Conference > EPE-PEMC 2000 - Topic 06: Power Electronics in Electrical Energy Generation, Transmission and Distribution > EPE-PEMC 2000 - Topic 06e: General Section

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   A Smart Relaying Scheme for High Impedance Faults in Distribution and Utilization Networks
By Sharaf A.M., Abu-Azab S.I. [View]
[Download]

Abstract: The paper presents a novel transient time domain relaying scheme for distribution/utilization networks. The scheme is based on graphical image feature extraction of a diagnostic feature vector xf that carries information about the fault types. The relaying algorithm is capable of detecting low current impedance type faults (HIF).

   Active Compensation of Earth Currents in a Low Voltage Insulated Neutral Ship System
By Dorobczynski L., Tarnapowicz D., Zeludziewicz R. [View]
[Download]

Abstract: Principles of active protection of persons against electric shock in insulated neutral, three phase, low voltage a.c. systems are presented. The protection is based on automatic compensation of leakage earth currents. A transistorised voltage controlled current regulated voltage source inverter in a 4-wire circuit forms the final control element of system. A DSP processor controls the protection system. The results of simulated and experimental researches are presented.

   Design and Performance of a Prototype Power Conditioning System (PCS) for Super-Conducting Magnetic Energy Storage (SMES)
By Liu Ping , Kang Yong, Dai Ke, Zhang H., Chen Jian [View]
[Download]

Abstract: This paper presents a prototype power conditioning system for super-conducting magnetic energy storage (SMES). The configuration of the PCS is a voltage source converter in series with a two quadrant DC/DC chopper. The circuit scheme, operation principles and control strategies are described in detail. Alternative methods of the super-conducting coil in experiment are discussed. Operation of the prototype SMES to provide accurate control of the AC side currents to control the active power and reactive power is demonstrated.

   Inventory of Electrical Configurations for Offshore Wind Farms
By Meyl C.R., de Haan S.W.H., Bauer P. [View]
[Download]

Abstract: An inventory is given of electrical configurations to collect the power from individual wind turbines and to transmit this power to an on-shore high-voltage power system node. The inventory concerns both constant speed and variable speed wind turbines and transmission by ac and dc. Innovative concepts with variable frequency and clusters of turbines that are connected to a common variable-frequency ac-bus or dc-bus are included. Three methods for dc-dc conversion are dicussed, namely the step-up chopper, the electronic dc transformer and series connection of the outputs of converters. Finally a tool for the evaluation of the economic and technical feasibility is discussed .

   Mutivariable Robust Power System Stabiliser Design Based on H8
By Bouhamida M., Denai M.A., Ahed L.M. [View]
[Download]

Abstract: This paper deals with the design and evaluation of a HY based PSS using the state space approach. HY design method leads to a fixed-structure and fixed-parameter robust controller. An essential prerequisite in the synthesis of HY is to obtain a nominal linear system model. Uncertainties in the model are taken into account in the specification of the cost-function weights. The effectiveness of the proposed PSS is demonstrated under different operating regimes. A comparative study of the proposed PSS with a conventional PSS such as PI and optimal state feedback controllers has been performed and the superiority of the HY based PSS in improving the transient stability of the power generator is demonstrated in a simulation environment.

   Performance Study of TCSC Application to Fault Current Limiters
By Yamazaki Y.*, Sugimoto S.*, Kouda I.*, Konishi H., Kikuchi A. [View]
[Download]

Abstract: Short circuit currents will exceed the rated current of circuit breakers in the near future, making their suppression an urgent task [1]. To suppress short circuit currents, the authors have been working on a new fault current limiter (FCL) which consists of a conventional current limiting reactor with a thyristor controlled series compensator (TCSC). In this paper, the performance study of the FCL is described using digital simulations and an analogue simulator. The study showed arresters of the TCSC suppressed not only overvoltages, but also fault currents and the proposed FCL was confirmed to have excellent fault current limiting ability and good power oscillation damping.

   Power Transformer with Superconducting Windings
By Kusdogan S., Perdahci C. [View]
[Download]

Abstract: The application of superconductive technology to various power apparatuses in electric power system will be greatly important from the viewpoint of energy and resources saving. Especially superconducting transformers using a superconducting as a field winding, have many merits,e.g. increasing transformer efficiency, improving power system stability and operation performance, and reducing size and weight in comparison with conventional transformers. This paper describes are circuit analysis calculation for superconducting transformer which is a three unit of core-form configuration, 500 / 22 kV, 1000 MVA.

   Synchronous Generator Stabiliser Design by Optimal Output Feedback
By Mariano S.J.*, Ferreira L.A.. [View]
[Download]

Abstract: A Power System Stabiliser (PSS) for synchronous generator is designed on the basis of optimal control theory. Results from optimal control theory are used together with a new procedure to specify Q and R proposed by the authors in [5]. Optimal output feedback is applied. The closed-loop performance of the system model is then evaluated for an input disturbance in the mechanical torque. Numerical results and illustrative figures are presented.

   Variable Speed Concept of Mobile Electrical Generating Sets
By Kurka O., Bršlica V. [View]
[Download]

Abstract: The variable speed concept represents quite new approach to the mobile electrical generating sets technology based on the use of driving engines of a speed varying optimally according to the generating set load. The output of a robust and reliable synchronous generator with permanent magnets with corresponding variable output voltage and frequency is transformed to the required constant voltage and frequency by means of power electronic converters. This concept decreases the fuel consumption and eliminates the amount of harmful emissions. The variable speed concept evokes new problems in the generating set dynamics and control, in suitable synchronous generator design and its operation with the power electronic converter.

EPE-PEMC 2000 - Topic 06e: General Section
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2000 - Conference > EPE-PEMC 2000 - Topic 06: Power Electronics in Electrical Energy Generation, Transmission and Distribution > EPE-PEMC 2000 - Topic 06e: General Section
	[return to parent folder]

	A Smart Relaying Scheme for High Impedance Faults in Distribution and Utilization Networks By Sharaf A.M., Abu-Azab S.I.	[View] [Download]
Abstract: The paper presents a novel transient time domain relaying scheme for distribution/utilization networks. The scheme is based on graphical image feature extraction of a diagnostic feature vector xf that carries information about the fault types. The relaying algorithm is capable of detecting low current impedance type faults (HIF).

	Active Compensation of Earth Currents in a Low Voltage Insulated Neutral Ship System By Dorobczynski L., Tarnapowicz D., Zeludziewicz R.	[View] [Download]
Abstract: Principles of active protection of persons against electric shock in insulated neutral, three phase, low voltage a.c. systems are presented. The protection is based on automatic compensation of leakage earth currents. A transistorised voltage controlled current regulated voltage source inverter in a 4-wire circuit forms the final control element of system. A DSP processor controls the protection system. The results of simulated and experimental researches are presented.

	Design and Performance of a Prototype Power Conditioning System (PCS) for Super-Conducting Magnetic Energy Storage (SMES) By Liu Ping , Kang Yong, Dai Ke, Zhang H., Chen Jian	[View] [Download]
Abstract: This paper presents a prototype power conditioning system for super-conducting magnetic energy storage (SMES). The configuration of the PCS is a voltage source converter in series with a two quadrant DC/DC chopper. The circuit scheme, operation principles and control strategies are described in detail. Alternative methods of the super-conducting coil in experiment are discussed. Operation of the prototype SMES to provide accurate control of the AC side currents to control the active power and reactive power is demonstrated.

	Inventory of Electrical Configurations for Offshore Wind Farms By Meyl C.R., de Haan S.W.H., Bauer P.	[View] [Download]
Abstract: An inventory is given of electrical configurations to collect the power from individual wind turbines and to transmit this power to an on-shore high-voltage power system node. The inventory concerns both constant speed and variable speed wind turbines and transmission by ac and dc. Innovative concepts with variable frequency and clusters of turbines that are connected to a common variable-frequency ac-bus or dc-bus are included. Three methods for dc-dc conversion are dicussed, namely the step-up chopper, the electronic dc transformer and series connection of the outputs of converters. Finally a tool for the evaluation of the economic and technical feasibility is discussed .

	Mutivariable Robust Power System Stabiliser Design Based on H8 By Bouhamida M., Denai M.A., Ahed L.M.	[View] [Download]
Abstract: This paper deals with the design and evaluation of a HY based PSS using the state space approach. HY design method leads to a fixed-structure and fixed-parameter robust controller. An essential prerequisite in the synthesis of HY is to obtain a nominal linear system model. Uncertainties in the model are taken into account in the specification of the cost-function weights. The effectiveness of the proposed PSS is demonstrated under different operating regimes. A comparative study of the proposed PSS with a conventional PSS such as PI and optimal state feedback controllers has been performed and the superiority of the HY based PSS in improving the transient stability of the power generator is demonstrated in a simulation environment.

	Performance Study of TCSC Application to Fault Current Limiters By Yamazaki Y., Sugimoto S., Kouda I., Konishi H., Kikuchi A.*	[View] [Download]
Abstract: Short circuit currents will exceed the rated current of circuit breakers in the near future, making their suppression an urgent task [1]. To suppress short circuit currents, the authors have been working on a new fault current limiter (FCL) which consists of a conventional current limiting reactor with a thyristor controlled series compensator (TCSC). In this paper, the performance study of the FCL is described using digital simulations and an analogue simulator. The study showed arresters of the TCSC suppressed not only overvoltages, but also fault currents and the proposed FCL was confirmed to have excellent fault current limiting ability and good power oscillation damping.

	Power Transformer with Superconducting Windings By Kusdogan S., Perdahci C.	[View] [Download]
Abstract: The application of superconductive technology to various power apparatuses in electric power system will be greatly important from the viewpoint of energy and resources saving. Especially superconducting transformers using a superconducting as a field winding, have many merits,e.g. increasing transformer efficiency, improving power system stability and operation performance, and reducing size and weight in comparison with conventional transformers. This paper describes are circuit analysis calculation for superconducting transformer which is a three unit of core-form configuration, 500 / 22 kV, 1000 MVA.

	Synchronous Generator Stabiliser Design by Optimal Output Feedback By Mariano S.J., Ferreira L.A..*	[View] [Download]
Abstract: A Power System Stabiliser (PSS) for synchronous generator is designed on the basis of optimal control theory. Results from optimal control theory are used together with a new procedure to specify Q and R proposed by the authors in [5]. Optimal output feedback is applied. The closed-loop performance of the system model is then evaluated for an input disturbance in the mechanical torque. Numerical results and illustrative figures are presented.

	Variable Speed Concept of Mobile Electrical Generating Sets By Kurka O., Bršlica V.	[View] [Download]
Abstract: The variable speed concept represents quite new approach to the mobile electrical generating sets technology based on the use of driving engines of a speed varying optimally according to the generating set load. The output of a robust and reliable synchronous generator with permanent magnets with corresponding variable output voltage and frequency is transformed to the required constant voltage and frequency by means of power electronic converters. This concept decreases the fuel consumption and eliminates the amount of harmful emissions. The variable speed concept evokes new problems in the generating set dynamics and control, in suitable synchronous generator design and its operation with the power electronic converter.