EPE Association: EPE 1997 â€“ 45: Dialogue Session DS9b: EMC

EPE 1997 â€“ 45: Dialogue Session DS9b: EMC
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1997 - Conference > EPE 1997 â€“ 45: Dialogue Session DS9b: EMC

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   COMPARATIVE EMISSIONS MEASUREMENTS FOR FULL-BRIDGE SWITCHING STRATEGIES
By R.M. Duke; B. Ram [View]
[Download]

Abstract: This paper reports on comparative conducted and radiated emissions measurements made over a range of switching frequencies (20kHz to 50kHz) and loads for four full-bridge DCDC converter switching strategies; conventional pulse width modulation switching, soft-switching, zero-voltage zero-current switching and a new low dissipation soft-switching strategy. From the experimental results there is conclusive evidence that the various "soft-switching" strategies show some advantage over traditional hard-switching in respect to measured emissions.

   FAST PREDICTION OF DIFFERENTIAL MODE NOISE INPUT FILTER REQUIREMENTS FOR FLYBACK AND BOOST UNITY POWER FACTOR CONVERTERS
By Michael A E. Andersen [View]
[Download]

Abstract: Two new and simple methods to make predictions of the differential mode input filter requirements are presented, one for flyback and one for boost unity power factor converters. They have been verified by measurements. They give the designer ability to predict the DM input noise filter requirements early in the design.

   INFLUENCE OF SYSTEM PARAMETERS ON EMC BEHAVIOUR OF IGBT INVERTERS
By F. Palis; R. Mecke; H. Mecke; T. Rummel [View]
[Download]

Abstract: Hard switching PWM inverter drives produce high conducted electromagnetic interferences (EMI). The EMI emission mainly depends on the cable length, the rated power of the induction motor, the de link voltage of the inverter and the switching time of the IGBT. The commonly use of EMI filters can not reduce the EM! noise below the limits in each case. The filter damping can be reduced due to the interaction between filter and drive system. Another method to limit the EMI spectrum especially in the high frequency range is the increase of switching time. A simple model is proposed to simulate the conducted interferences at every operation point of the drive system. The paper presents simulation and experimental investigations.

   ELECTROMAGNETIC INTERFERENCE PROPAGATION - A WIDE FREQUENCY RANGE EQUIVALENT CIRCUIT FOR THE TWO WINDING TRANSFORMER
By K. Fagiewicz; J. Luszcz [View]
[Download]

Abstract: The aim of this paper is to present an experimental method to obtain a wide frequency range equivalent circuit for two winding transformers. The method presented allows us to determine the stray capacitance of the transformers. The developed equivalent circuit consists of among others, ten capacitors which represent an electrostatic interaction between the primary windings, secondary windings and other elements, electrically connected to the earth.

   TECHNIQUES USED TO SUPPRESS ELECTROMAGNETIC INTERFERENCE IN A VARIABLE VOLTAGE VARIABLE FREQUENCY INVERTER
By N. Masoud; M. Abdallah; T. Emoto; J. Triplett [View]
[Download]

Abstract: The Cairo Metro Line 2 trains use variable voltage variable frequency (VVVF) pulse width modulated (PWM) inverters to power three phase ac traction motors. The trains also use power electronic devices in the DC to DC power conversion equipment that powers auxiliary equipment. This paper presents the techniques used to suppress electromagnetic interference (EMI) in the power circuits that could adversely effect other safety critical systems.

   INCREASED POLLUTION IN THE PROTECTIVE EARTH
By A. Larsson; M. Lundmark; J. Hagelberg [View]
[Download]

Abstract: EMC has received increasing interest over past decade. Several standards regarding EMC have been developed. Although manufacturers design and manufacture interference-free equipment in accordance with standards, disturbances are still a problem. According to the current EMC legislation, conducted emissions are to be measured using a LISN between the utility grid and the equipment under test. However, it should be noticed that there is no correspondence between the EMC environment measured at an installation site and the EMC environment measured by the LISN. In this paper some documented cases where electrical equipment are disturbing each other are highlighted and EMC standards are discussed. In the paper it is shown that EMC related problems occurring in the examples all have the same origin: current flow in the PE. The leakage current is fed into the PE via the filters or by a capacitive coupling to the ground. The increased use of power electronic equipment might lead to the need of a complete re-build of the entire grid. An alternative solution to the problem would be to stop the leakage current from being fed into the PE.

   INFLUENCE OF ELECTRIC PARAMETERS ON RADIATED PERTURBATIONS FROM STATIC CONVERTERS BY MOMENTS METHOD
By J. Ben Hadj Slama; G. Rojat [View]
[Download]

Abstract: During the last years, electromagnetic compatibility (EMC) problems have reached power electronics. In fact, an increase of electric power levels and semiconductor commutation frequencies makes static converters become a source of electromagnetic interference (EMI). The numerical study of the EMI can help the circuit designer to predict the radiated field and then to modify the circuit with the aim to satisfy International Standards. In this paper, we present the computational method that we use. This method is based on moments method coupled to a circuit simulator. After, we use the numerical tool to study the influence of electric parameters on the electromagnetic field radiated from circuits of power electronic converters. So the influence of the amplitude of the feeding source, the loaded current, and the chopping frequency is analysed. Numerical results concerning the radiated electric field by a circuit of a chopper are presented. Then, these results are compared to measurements realised at our laboratory. Numerical results are in agreement with experimental results. The numerical tool for EMI prediction can be used when circuits of power electronics are designed.

   DESIGN OF RESONANT FLYBACK CONVERTER UNDER EMC CONSTRAINT
By J. Schutz; A. Schellmanns; J. Roudet [View]
[Download]

Abstract: In most modern power electronic devices, transformers are used to transfer energy. We will see that it constitutes the key point in the knowledge of conducted emission in the Radio Frequency range (10kHz-80MHz). The sensitivity of the most dominant parameters will be analysed in order to achieve a better design.

   ANALYSIS OF EMI SOURCES INSIDE POWER ELECTRONIC CONVERTERS
By A. Di Napoli; F. Giulii Capponi; L. Solero [View]
[Download]

Abstract: Electromagnetic compatibility problematics in power electronics have rapidly risen to a primary role because of the fast transients and the high power involved with these components. The aim of this work is to provide an analysis of the possible emitting sources inside power converters. The procedure that has been followed will be described, starting from empirical observation in preliminary tests over two inverters. A brief discussion of the obtained results will provide a more general explanation of the origin of the observed frequencies. In order to reduce emissions, the modificatons in the layout of the converters that have been adopted will be presented. Final experimental results will prove the enhancement on the performances of the inverters that have been tested.

   EMC BEHAVIOUR AND MODELIZATION OF HIGH FREQUENCY CONVERTER FOR INDUCTION HEATING
By S. D. Bocus; S. El Baroudi; F. Bernot; A. Berthon [View]
[Download]

Abstract: This paper presents a study on electromagnetic perturbations due to high frequency resonant converters for induction heating. It proposes a simulation study based on SABER environment in order to have a software tool for designing resonant converters. Measurements have been carried out on an experimental induction heating system to quantify these perturbations. EMC sources have been localized and propagation modes identified.

   INFLUENCE OF PASSIVE COMPONENTS STRAY BEHAVIOURS ON SMPS CONDUCTED ELECTROMAGNETIC INTERFERENCES
By C. Gautier; E. Laboure; F. Costa; Ph. Petit; C. Labarre [View]
[Download]

Abstract: This paper deals with the influence of the parasitic effects of passive components in the generation of electromagnetic interferences in SMPS. A study concerning different kind of passive components, the PCB (Printed-Circuit Board), the power transformer and the filtering components is achieved and useful electrical models are proposed. The choice of the model's parameters will be discussed and the interest to adapt their complexity will be depicted in order to improve the simulation time and the accuracy of the results. Simulation and experimental results will be presented and compared.

   INFLUENCE OF THE IGBT SWITCHING PROCESSES ON THE ELECTROMAGNETIC COMPATIBILITY OF POWER INVERTERS
By R.J. Pasterczyk [View]
[Download]

Abstract: A new state-of-the-art of medium and high-power converters with the IGBT technology makes switching processes faster but increases in the same time the electromagnetic interference level. Electromagnetic compatibility of high-frequency converters are concerned with the application of high-current IGBT devices specially under hard switching operation. Influence of the commutation in different types of IGBT modules is discussed, their environment, their behaviour and weaknesses in the aspect of conducted and radiated EMI to meet the EMC european standards. Influence of driving strategy, mode of commutation, level of switched current like a circuit stray parameters effects on conducted perturbances are shown. Solutions are proposed to improve converter safety and to reduce emission level without degradation of high-switching frequency and inverter efficiency.

   SOME SIMPLE APPROXIMATIONS OF INTERFERENCE SPECTRA
By A. Nagel; R.W. De Doncker [View]
[Download]

Abstract: A detailed knowledge of the interference spectrum produced by power converters is the first step in EMC-design. For this reason the amplitude spectrum of typical interference sources is analyzed and discussed. Simple approximations are given which dramatically improve the calculation time and the optimization process of filter designs. Theoretical analysis and measurement results are presented.

EPE 1997 â€“ 45: Dialogue Session DS9b: EMC
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1997 - Conference > EPE 1997 â€“ 45: Dialogue Session DS9b: EMC
	[return to parent folder]

	COMPARATIVE EMISSIONS MEASUREMENTS FOR FULL-BRIDGE SWITCHING STRATEGIES By R.M. Duke; B. Ram	[View] [Download]
Abstract: This paper reports on comparative conducted and radiated emissions measurements made over a range of switching frequencies (20kHz to 50kHz) and loads for four full-bridge DCDC converter switching strategies; conventional pulse width modulation switching, soft-switching, zero-voltage zero-current switching and a new low dissipation soft-switching strategy. From the experimental results there is conclusive evidence that the various "soft-switching" strategies show some advantage over traditional hard-switching in respect to measured emissions.

	FAST PREDICTION OF DIFFERENTIAL MODE NOISE INPUT FILTER REQUIREMENTS FOR FLYBACK AND BOOST UNITY POWER FACTOR CONVERTERS By Michael A E. Andersen	[View] [Download]
Abstract: Two new and simple methods to make predictions of the differential mode input filter requirements are presented, one for flyback and one for boost unity power factor converters. They have been verified by measurements. They give the designer ability to predict the DM input noise filter requirements early in the design.

	INFLUENCE OF SYSTEM PARAMETERS ON EMC BEHAVIOUR OF IGBT INVERTERS By F. Palis; R. Mecke; H. Mecke; T. Rummel	[View] [Download]
Abstract: Hard switching PWM inverter drives produce high conducted electromagnetic interferences (EMI). The EMI emission mainly depends on the cable length, the rated power of the induction motor, the de link voltage of the inverter and the switching time of the IGBT. The commonly use of EMI filters can not reduce the EM! noise below the limits in each case. The filter damping can be reduced due to the interaction between filter and drive system. Another method to limit the EMI spectrum especially in the high frequency range is the increase of switching time. A simple model is proposed to simulate the conducted interferences at every operation point of the drive system. The paper presents simulation and experimental investigations.

	ELECTROMAGNETIC INTERFERENCE PROPAGATION - A WIDE FREQUENCY RANGE EQUIVALENT CIRCUIT FOR THE TWO WINDING TRANSFORMER By K. Fagiewicz; J. Luszcz	[View] [Download]
Abstract: The aim of this paper is to present an experimental method to obtain a wide frequency range equivalent circuit for two winding transformers. The method presented allows us to determine the stray capacitance of the transformers. The developed equivalent circuit consists of among others, ten capacitors which represent an electrostatic interaction between the primary windings, secondary windings and other elements, electrically connected to the earth.

	TECHNIQUES USED TO SUPPRESS ELECTROMAGNETIC INTERFERENCE IN A VARIABLE VOLTAGE VARIABLE FREQUENCY INVERTER By N. Masoud; M. Abdallah; T. Emoto; J. Triplett	[View] [Download]
Abstract: The Cairo Metro Line 2 trains use variable voltage variable frequency (VVVF) pulse width modulated (PWM) inverters to power three phase ac traction motors. The trains also use power electronic devices in the DC to DC power conversion equipment that powers auxiliary equipment. This paper presents the techniques used to suppress electromagnetic interference (EMI) in the power circuits that could adversely effect other safety critical systems.

	INCREASED POLLUTION IN THE PROTECTIVE EARTH By A. Larsson; M. Lundmark; J. Hagelberg	[View] [Download]
Abstract: EMC has received increasing interest over past decade. Several standards regarding EMC have been developed. Although manufacturers design and manufacture interference-free equipment in accordance with standards, disturbances are still a problem. According to the current EMC legislation, conducted emissions are to be measured using a LISN between the utility grid and the equipment under test. However, it should be noticed that there is no correspondence between the EMC environment measured at an installation site and the EMC environment measured by the LISN. In this paper some documented cases where electrical equipment are disturbing each other are highlighted and EMC standards are discussed. In the paper it is shown that EMC related problems occurring in the examples all have the same origin: current flow in the PE. The leakage current is fed into the PE via the filters or by a capacitive coupling to the ground. The increased use of power electronic equipment might lead to the need of a complete re-build of the entire grid. An alternative solution to the problem would be to stop the leakage current from being fed into the PE.

	INFLUENCE OF ELECTRIC PARAMETERS ON RADIATED PERTURBATIONS FROM STATIC CONVERTERS BY MOMENTS METHOD By J. Ben Hadj Slama; G. Rojat	[View] [Download]
Abstract: During the last years, electromagnetic compatibility (EMC) problems have reached power electronics. In fact, an increase of electric power levels and semiconductor commutation frequencies makes static converters become a source of electromagnetic interference (EMI). The numerical study of the EMI can help the circuit designer to predict the radiated field and then to modify the circuit with the aim to satisfy International Standards. In this paper, we present the computational method that we use. This method is based on moments method coupled to a circuit simulator. After, we use the numerical tool to study the influence of electric parameters on the electromagnetic field radiated from circuits of power electronic converters. So the influence of the amplitude of the feeding source, the loaded current, and the chopping frequency is analysed. Numerical results concerning the radiated electric field by a circuit of a chopper are presented. Then, these results are compared to measurements realised at our laboratory. Numerical results are in agreement with experimental results. The numerical tool for EMI prediction can be used when circuits of power electronics are designed.

	DESIGN OF RESONANT FLYBACK CONVERTER UNDER EMC CONSTRAINT By J. Schutz; A. Schellmanns; J. Roudet	[View] [Download]
Abstract: In most modern power electronic devices, transformers are used to transfer energy. We will see that it constitutes the key point in the knowledge of conducted emission in the Radio Frequency range (10kHz-80MHz). The sensitivity of the most dominant parameters will be analysed in order to achieve a better design.

	ANALYSIS OF EMI SOURCES INSIDE POWER ELECTRONIC CONVERTERS By A. Di Napoli; F. Giulii Capponi; L. Solero	[View] [Download]
Abstract: Electromagnetic compatibility problematics in power electronics have rapidly risen to a primary role because of the fast transients and the high power involved with these components. The aim of this work is to provide an analysis of the possible emitting sources inside power converters. The procedure that has been followed will be described, starting from empirical observation in preliminary tests over two inverters. A brief discussion of the obtained results will provide a more general explanation of the origin of the observed frequencies. In order to reduce emissions, the modificatons in the layout of the converters that have been adopted will be presented. Final experimental results will prove the enhancement on the performances of the inverters that have been tested.

	EMC BEHAVIOUR AND MODELIZATION OF HIGH FREQUENCY CONVERTER FOR INDUCTION HEATING By S. D. Bocus; S. El Baroudi; F. Bernot; A. Berthon	[View] [Download]
Abstract: This paper presents a study on electromagnetic perturbations due to high frequency resonant converters for induction heating. It proposes a simulation study based on SABER environment in order to have a software tool for designing resonant converters. Measurements have been carried out on an experimental induction heating system to quantify these perturbations. EMC sources have been localized and propagation modes identified.

	INFLUENCE OF PASSIVE COMPONENTS STRAY BEHAVIOURS ON SMPS CONDUCTED ELECTROMAGNETIC INTERFERENCES By C. Gautier; E. Laboure; F. Costa; Ph. Petit; C. Labarre	[View] [Download]
Abstract: This paper deals with the influence of the parasitic effects of passive components in the generation of electromagnetic interferences in SMPS. A study concerning different kind of passive components, the PCB (Printed-Circuit Board), the power transformer and the filtering components is achieved and useful electrical models are proposed. The choice of the model's parameters will be discussed and the interest to adapt their complexity will be depicted in order to improve the simulation time and the accuracy of the results. Simulation and experimental results will be presented and compared.

	INFLUENCE OF THE IGBT SWITCHING PROCESSES ON THE ELECTROMAGNETIC COMPATIBILITY OF POWER INVERTERS By R.J. Pasterczyk	[View] [Download]
Abstract: A new state-of-the-art of medium and high-power converters with the IGBT technology makes switching processes faster but increases in the same time the electromagnetic interference level. Electromagnetic compatibility of high-frequency converters are concerned with the application of high-current IGBT devices specially under hard switching operation. Influence of the commutation in different types of IGBT modules is discussed, their environment, their behaviour and weaknesses in the aspect of conducted and radiated EMI to meet the EMC european standards. Influence of driving strategy, mode of commutation, level of switched current like a circuit stray parameters effects on conducted perturbances are shown. Solutions are proposed to improve converter safety and to reduce emission level without degradation of high-switching frequency and inverter efficiency.

	SOME SIMPLE APPROXIMATIONS OF INTERFERENCE SPECTRA By A. Nagel; R.W. De Doncker	[View] [Download]
Abstract: A detailed knowledge of the interference spectrum produced by power converters is the first step in EMC-design. For this reason the amplitude spectrum of typical interference sources is analyzed and discussed. Simple approximations are given which dramatically improve the calculation time and the optimization process of filter designs. Theoretical analysis and measurement results are presented.