EPE Association: EPE 1995 - 44 - Dialogue Session DS5d: Harmonics, Renewable Energy Systems, Simulation

EPE 1995 - 44 - Dialogue Session DS5d: Harmonics, Renewable Energy Systems, Simulation
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1995 - Conference > EPE 1995 - 44 - Dialogue Session DS5d: Harmonics, Renewable Energy Systems, Simulation

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   IMPACT ON THE DISTRIBUTION AND TRANSMISSION SYSTEMS OF HARMONIC CURRENT INJECTION DUE TO CAPACITIVE LOAD RECTIFIERS IN COMM., RES. AND IND. INSTALLATIONS
By P. Rioual; T. Deflandre [View]
[Download]

Abstract: This paper proposes a study of the capacitive load rectifier and its impact on the network. These rectifiers are indeed widespread at EDF customers. Customers harmonic current injection level resulting from the presence of capacitive load rectifiers has been measured, analysed, evaluated and reviewed with the appropriate solutions.

   HARMONIC INTERACTION IN BACK-TO-BACK HVDC LINK BETWEEN AC SYSTEMS AT DIFFERENT FREQUENCIES
By M.P. Bottino; B. Delfino; G. Garzi; A. Morini [View]
[Download]

Abstract: The origin and the transfer of non-characteristic harmonies via DC link in back-to-back HVDC tie interconnecting two different frequencies power systems are the subject of this paper. The reasons of these particular harmonics, usually not predicted by the conventional procedures of computation, are described whether in balanced or unbalanced conditions. To investigate in detail this problem, a digital simulation approach of a back-to-back HVDC tie, planned between Brazil and Argentina, is followed in this paper by using the Alternative Transient Program (ATP), as flexible and useful tool of computation. The voltages and currents wave-shapes of the AC and DC sides have been studied with the Fourier Analysis and FFT algorithm: the results are presented, discussed and explained.

   ACTUAL GENERATION AND SUMMATION EFFECTS OF HARMONIC CURRENTS PRODUCED BY MULTIPLE CONVERTER UNITS IN THE FRENCH INDUSTRY
By Jacques Letzelter; Michel Le Bitoux; Daniel Sadarnac [View]
[Download]

Abstract: An a priori method for modelling the harmonie currents generated by converters used in industry is proposed here. It is based on a set of hypotheses conceming the equipment used by a category of EDF's customers. The equipment is linked to a set of parameters specific to energy conversion structures for evaluating current injection and variations for each type of equipment. Finally, the study of interaction phenomena between several converters makes it possible to validate a pattern totalling the currents absorbed by such equipment and accounting for harmonic reduction effects caused by the various loads in the industrial network.

   POWER CONDITIONING FOR PHOTOVOLTAIC SUPPLY UNITS FOR RAILWAY APPLICATIONS
By L. Lori; P. Redi; M. Ruzinsky [View]
[Download]

Abstract: Power supplies systems in the railway lines signalling systems requires no break service. In the last ten years a large quantity of photovoltaic systems have been tested in the Italian railway network in order to gain experience with the design of no break power systems. The development of the systems bas evolved from traditional stand-alone with high capacity storage batteries to grid connected high reliability systems with a reduced storage capacity. A new concept has been recently introduced using bidirectional energy converters which send to the grid the excess of energy from the PV array.

   RESTRICTION OF HARMONIC CURRENTS DUE TO POWER-ELECTRONIC-DRIVES AND VAPOR DISCHARGE LAMPS
By H. Mijnarends; G. Blom [View]
[Download]

Abstract: In the Netherlands we expect a large augumentation of power electronic drives to possibly 70% of the total electricity consumption, encouraged by the dutch energy programs. Due to this expectation the dutch electricity companies made new guidelines, which are considered to be a good compromise between the interest of the owner the drives the electricity company. Both can be obliged to make investments. An outstanding knowlegde of power electronics and network-behaviour is a must. In between guidelines for the use of vapor discharge lamps have been made on the same base.

   APPLICATION OF NEURAL NETWORKS TO PREDICTING HARMONICS
By L. L. Lai; F. Ndeh-Che; H. Braun; R. Hui; A. B. Serrano [View]
[Download]

Abstract: This paper describes the use of neural networks to predicting harmonies in AC/DC converters. The converter incorporates an active harmonic suppression filter. The parameters of the filter are varied to vary the level of harmonies. The neural network is used to learn the percentage of harmonies in the system from the variation in the filter parameters. The trained neural network can then be used to predict the level of harmonics for a particular set of filter parameters. Different neural network learning algorithms have been investigated and the difference between the predicted and simulated values are compared.

   VOLTAGE ANGLE CONTROL OF A VOLTAGE SOURCE INVERTER - APPLICATION TO A GRID-CONNECTED WIND TURBINE
By J. Svensson [View]
[Download]

Abstract: The voltage angle control of an inverter connected to the grid in a wind turbine application is presented. To analyse the system and find out the proper parameters of the controller the system is linearized at an operating point. The inverter is modelled by using only fondamental voltages. By using a PI-controller for the DC-link voltage and feedforward of the generator/rectifier current the voltage angle control can be used. The bandwidth of the inverter system is approximately 20 to 30 Hz. The parameters and the bandwidth of the system are determined by the allowed DC-link voltage fluctuation. The system can be analysed using a linearized model unless the series inductance is very large. The controller using feedforward is insensitive to series inductance variations, and the fluctuations depend on the size of the DC-link capacitor and the frequency and amplitude of the generator/rectifier current.

   HARMONIC EVALUATION IN LIGHT DIMMER SYSTEM BY A PROBABILISTIC APPROACH
By P. Guerin; M. Machmoum; R. Le Doeuff [View]
[Download]

Abstract: In this paper, the problem of hannonic pollution in electrical network is dealt with a probabilistic approach. An analytical method to calculate hannonic currents produced by a large number of light dimmers is presented. The Monte Carlo technique is used to determine the resultant functions of the sum of harmonies in the electrical network. The study takes into account the number of dimmers and the random variations of their control angles. Measurements recorded during a show in a theatre, are reported and compared with simulation results.

   PROBABILISTIC MODELLING OF NETWORK HARMONIC IMPEDANCE DUE TO RANDOM LOAD VARIATION
By L. Pierrat; B. Susetyo [View]
[Download]

Abstract: To study harmonic disturbances due to power electronic converters, the power network's harmonie impedance should be modelled: here a new analytical formulation is proposed. The method is based on the multivariate gaussian distribution which is characterized by the mean values vector and a covariance matrix. This method is using to study harmonic impedance sensitivity due to random variations of network an loads parameters.

   Modeling and Analysis of Aircraft Power System Harmonics
By K. J. Karimi [View]
[Download]

Abstract: Modern commercial aircraft Electric Power Systems (EPS) include many nonlinear equipment which produce harmonics. The addition of all the current harmonics could result in a power system with unacceptable levels of voltage distortion. It is important to be able to predict the levels of voltage distortion at early program stages to correct any potential problems and avoid costly redesigns. In this paper the nature and sources of harmonic producing equipment are described. These sources of harmonics and their effect on aircraft power system operation are described. A computer model of the Boeing 777 EPS has been developed. This model has been used to calculate voltage harmonics for various airplane configurations and flight conditions. A description of this model and the models used for various components are given. Tests performed to validate these models are described. Comparison of experimental results with analytical model predictions are given.

EPE 1995 - 44 - Dialogue Session DS5d: Harmonics, Renewable Energy Systems, Simulation
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1995 - Conference > EPE 1995 - 44 - Dialogue Session DS5d: Harmonics, Renewable Energy Systems, Simulation
	[return to parent folder]

	IMPACT ON THE DISTRIBUTION AND TRANSMISSION SYSTEMS OF HARMONIC CURRENT INJECTION DUE TO CAPACITIVE LOAD RECTIFIERS IN COMM., RES. AND IND. INSTALLATIONS By P. Rioual; T. Deflandre	[View] [Download]
Abstract: This paper proposes a study of the capacitive load rectifier and its impact on the network. These rectifiers are indeed widespread at EDF customers. Customers harmonic current injection level resulting from the presence of capacitive load rectifiers has been measured, analysed, evaluated and reviewed with the appropriate solutions.

	HARMONIC INTERACTION IN BACK-TO-BACK HVDC LINK BETWEEN AC SYSTEMS AT DIFFERENT FREQUENCIES By M.P. Bottino; B. Delfino; G. Garzi; A. Morini	[View] [Download]
Abstract: The origin and the transfer of non-characteristic harmonies via DC link in back-to-back HVDC tie interconnecting two different frequencies power systems are the subject of this paper. The reasons of these particular harmonics, usually not predicted by the conventional procedures of computation, are described whether in balanced or unbalanced conditions. To investigate in detail this problem, a digital simulation approach of a back-to-back HVDC tie, planned between Brazil and Argentina, is followed in this paper by using the Alternative Transient Program (ATP), as flexible and useful tool of computation. The voltages and currents wave-shapes of the AC and DC sides have been studied with the Fourier Analysis and FFT algorithm: the results are presented, discussed and explained.

	ACTUAL GENERATION AND SUMMATION EFFECTS OF HARMONIC CURRENTS PRODUCED BY MULTIPLE CONVERTER UNITS IN THE FRENCH INDUSTRY By Jacques Letzelter; Michel Le Bitoux; Daniel Sadarnac	[View] [Download]
Abstract: An a priori method for modelling the harmonie currents generated by converters used in industry is proposed here. It is based on a set of hypotheses conceming the equipment used by a category of EDF's customers. The equipment is linked to a set of parameters specific to energy conversion structures for evaluating current injection and variations for each type of equipment. Finally, the study of interaction phenomena between several converters makes it possible to validate a pattern totalling the currents absorbed by such equipment and accounting for harmonic reduction effects caused by the various loads in the industrial network.

	POWER CONDITIONING FOR PHOTOVOLTAIC SUPPLY UNITS FOR RAILWAY APPLICATIONS By L. Lori; P. Redi; M. Ruzinsky	[View] [Download]
Abstract: Power supplies systems in the railway lines signalling systems requires no break service. In the last ten years a large quantity of photovoltaic systems have been tested in the Italian railway network in order to gain experience with the design of no break power systems. The development of the systems bas evolved from traditional stand-alone with high capacity storage batteries to grid connected high reliability systems with a reduced storage capacity. A new concept has been recently introduced using bidirectional energy converters which send to the grid the excess of energy from the PV array.

	RESTRICTION OF HARMONIC CURRENTS DUE TO POWER-ELECTRONIC-DRIVES AND VAPOR DISCHARGE LAMPS By H. Mijnarends; G. Blom	[View] [Download]
Abstract: In the Netherlands we expect a large augumentation of power electronic drives to possibly 70% of the total electricity consumption, encouraged by the dutch energy programs. Due to this expectation the dutch electricity companies made new guidelines, which are considered to be a good compromise between the interest of the owner the drives the electricity company. Both can be obliged to make investments. An outstanding knowlegde of power electronics and network-behaviour is a must. In between guidelines for the use of vapor discharge lamps have been made on the same base.

	APPLICATION OF NEURAL NETWORKS TO PREDICTING HARMONICS By L. L. Lai; F. Ndeh-Che; H. Braun; R. Hui; A. B. Serrano	[View] [Download]
Abstract: This paper describes the use of neural networks to predicting harmonies in AC/DC converters. The converter incorporates an active harmonic suppression filter. The parameters of the filter are varied to vary the level of harmonies. The neural network is used to learn the percentage of harmonies in the system from the variation in the filter parameters. The trained neural network can then be used to predict the level of harmonics for a particular set of filter parameters. Different neural network learning algorithms have been investigated and the difference between the predicted and simulated values are compared.

	VOLTAGE ANGLE CONTROL OF A VOLTAGE SOURCE INVERTER - APPLICATION TO A GRID-CONNECTED WIND TURBINE By J. Svensson	[View] [Download]
Abstract: The voltage angle control of an inverter connected to the grid in a wind turbine application is presented. To analyse the system and find out the proper parameters of the controller the system is linearized at an operating point. The inverter is modelled by using only fondamental voltages. By using a PI-controller for the DC-link voltage and feedforward of the generator/rectifier current the voltage angle control can be used. The bandwidth of the inverter system is approximately 20 to 30 Hz. The parameters and the bandwidth of the system are determined by the allowed DC-link voltage fluctuation. The system can be analysed using a linearized model unless the series inductance is very large. The controller using feedforward is insensitive to series inductance variations, and the fluctuations depend on the size of the DC-link capacitor and the frequency and amplitude of the generator/rectifier current.

	HARMONIC EVALUATION IN LIGHT DIMMER SYSTEM BY A PROBABILISTIC APPROACH By P. Guerin; M. Machmoum; R. Le Doeuff	[View] [Download]
Abstract: In this paper, the problem of hannonic pollution in electrical network is dealt with a probabilistic approach. An analytical method to calculate hannonic currents produced by a large number of light dimmers is presented. The Monte Carlo technique is used to determine the resultant functions of the sum of harmonies in the electrical network. The study takes into account the number of dimmers and the random variations of their control angles. Measurements recorded during a show in a theatre, are reported and compared with simulation results.

	PROBABILISTIC MODELLING OF NETWORK HARMONIC IMPEDANCE DUE TO RANDOM LOAD VARIATION By L. Pierrat; B. Susetyo	[View] [Download]
Abstract: To study harmonic disturbances due to power electronic converters, the power network's harmonie impedance should be modelled: here a new analytical formulation is proposed. The method is based on the multivariate gaussian distribution which is characterized by the mean values vector and a covariance matrix. This method is using to study harmonic impedance sensitivity due to random variations of network an loads parameters.

	Modeling and Analysis of Aircraft Power System Harmonics By K. J. Karimi	[View] [Download]
Abstract: Modern commercial aircraft Electric Power Systems (EPS) include many nonlinear equipment which produce harmonics. The addition of all the current harmonics could result in a power system with unacceptable levels of voltage distortion. It is important to be able to predict the levels of voltage distortion at early program stages to correct any potential problems and avoid costly redesigns. In this paper the nature and sources of harmonic producing equipment are described. These sources of harmonics and their effect on aircraft power system operation are described. A computer model of the Boeing 777 EPS has been developed. This model has been used to calculate voltage harmonics for various airplane configurations and flight conditions. A description of this model and the models used for various components are given. Tests performed to validate these models are described. Comparison of experimental results with analytical model predictions are given.