EPE Association: EPE 2020 - LS1d: Converter Modelling

EPE 2020 - LS1d: Converter Modelling
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2020 ECCE Europe - Conference > EPE 2020 - Topic 02: Power Converter Topologies and Design > EPE 2020 - LS1d: Converter Modelling

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   Detailed Simulation Model of an Asymmetrical Half-Bridge PWM Converter with Synchronous Rectification including Parasitic Elements
By Benedikt KOHLHEPP [View]
[Download]

Abstract: The asymmetrical half-bridge converter implemented with GaN-switches represents a great candidate for achieving high power density and high efficiency. These requirements call for the implementation of a synchronous rectifier on the secondary side to push the efficiency. Furthermore, higher switching frequencies lead to smaller passive components needed for compact power supplies. In order to gain accurate and reliable simulation results for these high switching frequencies, this paper presents a detailed simulation model featuring parasitics of all semiconductors and transformer capacitances. Besides current and voltage waveforms of one switching cycle, this model allows for studying ZVS transitions as well. Measurements on a practical test setup deliver waveforms very close to the simulation results and thus prove the validity of the simulation model.

   Development of an Algorithm for the Automation of the Modelling Process of Power Converters
By Jon ANZOLA [View]
[Download]

Abstract: By the time goes by, the energetic efficiency gains more and more importance inside the strategic plans of companies that are focused on energy storage and conversion. For this reason, these same companies seek the necessity of developing algorithms capable of modelling and simulating the behaviour of power converters. Indeed, by modelling, it is possible to foresee converters' response to different input signals and comprehend better their behaviour without building a prototype. However, the process of obtaining the mathematical representation of a converter is high time consuming and, in case several topologies need to be compared, it can result in a laborious procedure. For this reason, this project has focused on the idea of developing a tool that could automatize the modelling process of a given converter. The presented algorithm is based on GSSAM and, in order to see its flexibility and precision, the results are compared to a switched model, validating the algorithm.

   Impedance-Based Modeling of a Three-level Converter Under Balanced and Unbalanced Condition for the Stability Analysis of Bipolar LVDC Grids
By Thomas ROOSE [View]
[Download]

Abstract: This paper presents an impedance-based assessment to identify potential instabilities in bipolar LVDC grids where the voltage is controlled by a three-level DC-DC converter. As an essential step to perform the assessment, the small-signal admittance matrix of the three-level DC-DC converter is analytically derived and verified by a non-linear switched model implemented in the EMT-type software PSCAD. It is shown that the converter admittance matrix exhibits non-passive behavior at frequencies above 500 Hz. Furthermore, the non-passivity is found to be dependent on the operating point of the converter. This behavior can negatively interact with resonances of bipolar LVDC systems, e.g. LC-filter resonances, leading to unstable high-frequency oscillations and system instability.

EPE 2020 - LS1d: Converter Modelling
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2020 ECCE Europe - Conference > EPE 2020 - Topic 02: Power Converter Topologies and Design > EPE 2020 - LS1d: Converter Modelling
	[return to parent folder]

	Detailed Simulation Model of an Asymmetrical Half-Bridge PWM Converter with Synchronous Rectification including Parasitic Elements By Benedikt KOHLHEPP	[View] [Download]
Abstract: The asymmetrical half-bridge converter implemented with GaN-switches represents a great candidate for achieving high power density and high efficiency. These requirements call for the implementation of a synchronous rectifier on the secondary side to push the efficiency. Furthermore, higher switching frequencies lead to smaller passive components needed for compact power supplies. In order to gain accurate and reliable simulation results for these high switching frequencies, this paper presents a detailed simulation model featuring parasitics of all semiconductors and transformer capacitances. Besides current and voltage waveforms of one switching cycle, this model allows for studying ZVS transitions as well. Measurements on a practical test setup deliver waveforms very close to the simulation results and thus prove the validity of the simulation model.

	Development of an Algorithm for the Automation of the Modelling Process of Power Converters By Jon ANZOLA	[View] [Download]
Abstract: By the time goes by, the energetic efficiency gains more and more importance inside the strategic plans of companies that are focused on energy storage and conversion. For this reason, these same companies seek the necessity of developing algorithms capable of modelling and simulating the behaviour of power converters. Indeed, by modelling, it is possible to foresee converters' response to different input signals and comprehend better their behaviour without building a prototype. However, the process of obtaining the mathematical representation of a converter is high time consuming and, in case several topologies need to be compared, it can result in a laborious procedure. For this reason, this project has focused on the idea of developing a tool that could automatize the modelling process of a given converter. The presented algorithm is based on GSSAM and, in order to see its flexibility and precision, the results are compared to a switched model, validating the algorithm.

	Impedance-Based Modeling of a Three-level Converter Under Balanced and Unbalanced Condition for the Stability Analysis of Bipolar LVDC Grids By Thomas ROOSE	[View] [Download]
Abstract: This paper presents an impedance-based assessment to identify potential instabilities in bipolar LVDC grids where the voltage is controlled by a three-level DC-DC converter. As an essential step to perform the assessment, the small-signal admittance matrix of the three-level DC-DC converter is analytically derived and verified by a non-linear switched model implemented in the EMT-type software PSCAD. It is shown that the converter admittance matrix exhibits non-passive behavior at frequencies above 500 Hz. Furthermore, the non-passivity is found to be dependent on the operating point of the converter. This behavior can negatively interact with resonances of bipolar LVDC systems, e.g. LC-filter resonances, leading to unstable high-frequency oscillations and system instability.