Implementation of Energy based Hysteresis Model in LTspice for power electronics applications Fabien Sixdenier, Riccardo Scorretti, Vittorio Bertolini, Antonio Faba-Universite Claude Bernard Lyon INSA Lyon, Ecole Centrale de Lyon, France † University of Perugia, Italy

 Implementation of Energy based Hysteresis Model in LTspice for power 1 electronics applications Fabien Sixdenier∗, Riccardo Scorretti∗†, Vittorio Bertolini†, Antonio Faba† 

Abstract—Circuit simulation software is routinely used in power electronics to analyze systems with magnetic cores exhibiting significant hysteresis behavior. This paper presents the implementation of the Energy-Based Hysteresis Model (EBHM) in LTspice to account for hysteresis in magnetic cores of inductors. The model is validated via transient simulations of a DC/DC buck converter, comparing results with experimental measurements across various input voltages, frequencies, and duty cycles. While the model accurately predicts average current, discrepancies in current ripple are observed, attributed to core-to-core variability in ferrite materials. The EBHM implementation offers a significant computational advantage, with simulation times remaining under 10 seconds even for highly saturated cases. The model’s robustness and potential for extension to dynamic effects (e.g., eddy currents) are discussed, along with its applicability to other power electronics topologies.

READ FULL ARTICLE: https://hal.science/hal-05422867/document

Study of a High-Power Medium Frequency Transformer Using Amorphous Magnetic Material by Shichong Zhang,Dezhi Chen * and Baodong Bai- School of Electrical Engineering, Shenyang University of Technology, Shenyang 110027, China

 

Study of a High-Power Medium Frequency Transformer Using Amorphous Magnetic Material by Shichong ZhangORCID,Dezhi Chen * andBaodong Bai School of Electrical Engineering, Shenyang University of Technology, Shenyang 110027, China

Abstract A shell-type medium frequency transformer (MFT) using amorphous alloy material is designed for high-power electronic applications. The optimal area product design method is adopted to design an MFT, which maximizes the high efficiency and power density, minimizes the loss and volume, and meets the limitations of insulation and temperature rise. Then, a 20 kVA/10 kHz MFT is designed. To ensure the rationality of the MFT design, the magnetic properties of the amorphous alloy material are measured, and finite element simulations are carried out based on measured magnetic properties. The magnetic flux density, loss, and temperature rise of the designed MFT are analyzed. Finally, a 20 kVA/10 kHz MFT prototype is fabricated, and experimental tests are carried out. The loss and temperature rise of the MFT prototype are within reason, which verifies the effectiveness of the proposed scheme. 

READ FULL ARTICLE:https://www.mdpi.com/2073-8994/14/10/2129

SUB SYNCHRONOUS OSCILLATIONS IN MODERN TRANSMISSION GRIDS DESIGN AND VALIDATION OF NOVEL CONCEPTS FOR MITIGATING ADVERSE DFIG-SSR INTERACTIONS

SUB SYNCHRONOUS OSCILLATIONS IN MODERN TRANSMISSION GRIDS DESIGN AND VALIDATION OF NOVEL CONCEPTS FOR MITIGATING ADVERSE DFIG-SSR INTERACTIONS

Dissertation for the degree of Doctor at Delft University of Technology, by the authority of the Rector Magnificus Prof.dr.ir. T.H.J.J. van der Hagen, Chair of the Board for Doctorates, to be defended in public on Thursday, 24 June 2021 at 15:00 by Vinay Naraindatt SEWDIEN Civil Engineer, KU Leuven, Belgium born in Paramaribo, Suriname 

 SUMMARY 

The ongoing energy transition results on the one hand in a proliferation of power electronics interfaced devices and on the other hand in a decreasing availability of conventional synchronous generation. These developments pose important challenges for transmission system operators to operate a low inertia power system. As part of my research I have created a list of 28 related challenges, validated by industry, that are grouped into three categories: (i) Reduced Voltage and Frequency Support, (ii) New Operation of the Power System and (iii) New Behaviour of the Power System. The focus of this research is on category (iii) and addresses the sub synchronous resonance (SSR) phenomenon between a doubly fed induction generator (DFIG) and a series compensated transmission line. This phenomenon is denoted as DFIG-SSR in this thesis. Failing to adequately address resonances results in among others degradation of the power quality, protection tripping, physical damage to power system equipment and ultimately instability in the power system. The main objective of this research is to investigate and validate the degree of effectiveness of the existing phase imbalance compensation concept, as well as to design and validate a new prediction gain scheduling control concept for mitigating DFIG-SSR. For these investigation, design and validation activities, electromagnetic transient (EMT) simulation models of the DFIG wind turbine are developed using Power System Computer Aided Design (PSCAD). In line with common practice, the topology of the IEEE First Benchmark Model is used as a smallsize study model, whereas the larger IEEE 39-Bus Model is used for validation of the obtained results. The impedance based stability method is used to quantify the impact of potential mitigation solutions on DFIG-SSR. This dissertation has three main contributions. First, recommendations are developed to obtain the frequency-dependent impedance of power electronics interfaced devices through numerical EMT simulations of black box, non-linear simulation models. These recommendations are crucial to perform interaction studies. The influence of the impedance calculation time, model granularity and composition of the perturbation signal on the obtained impedance is presented and guidelines are given on how to select the correct model and parameters for the numerical simulations. Second, a methodology is developed that enables the systematic assessment and design of the phase imbalance compensation concept for mitigating DFIG-SSR. The phase imbalance compensation concept is an alternative way of fixed series compensation, where the imbalance is implemented as a series or as a parallel resonance scheme in either one or two phases of the transmission line. The influence of the series and parallel schemes as well as the influence of their different degrees of asymmetry on the stability of the system are rigorously investigated. The series scheme introduces one series resonance in the power system, where the resonance frequency increases as a function of the degree of asymmetry. The increase is more pronounced viii SUMMARY when the series scheme is implemented in two phases. The parallel scheme on the other hand decreases the series resonance frequency and this decrease is more pronounced when the scheme is implemented in two phases. However, the parallel scheme introduces an additional parallel resonance with a frequency between 20 and 30 Hz, the stability of which depends on the degree of asymmetry.

FULL THESIS :https://research.tudelft.nl/files/93510648/Thesis_for_ONLINE_v2.pdf

Satellite Electrical Power System -Nuno Laranjeira Ramo Thesis to obtain the Master of Science Degree in Electronics Engineering -INSTITUTO SUPERIOR DE LISBOA

Satellite Electrical Power System by Nuno Laranjeira Ramo Thesis to obtain the Master of Science Degree in Electronics Engineering -INSTITUTO SUPERIOR DE LISBOA 

 Abstract The Electrical Power System (EPS) is an electronic circuit board that is designed to supply and manage process the energy in an efficient way. This document describes the design architecture and circuits involved for an EPS deployed in the ISTsat ONE nano satellite project. The EPS generates energy through its solar panels which is stored in the battery and then, using DC-DC switching voltage regulators, converts it to the final voltage of +3.3 V and +5 V, supplying these voltage rails for the rest of the subsystems of the satellite. This architecture meets the performance and size requirements of CubeSat architecture (cubic shape with 10 cm of edge, satellite with less than 10 kg). The EPS is composed by various systems, namely: Maximum Power Point Tracking mechanism to achieve maximum efficiency in the conversion of solar energy, a 20.8 Wh battery, solar panels and redundant circuitry to continuously ensure the power supply to the satellite. The EPS is a subsystem of the ISTsat ONE and as such, it communicates with other subsystems present in the satellite sending data logs, error warnings as well as receiving commands.

FULL THESIS: https://istsat-one.tecnico.ulisboa.pt/~istsat-one.daemon/docs/thesis_NunoRamos_EPS_2018.pdf

Grid-Forming Inverters as Synchronous Machine Replacements: Stability Analysis and Overcurrent Protection Strategies-MASTER THESIS ENGINEERING ELERTRICAL-ROBERTO NETO-Università di Padova

 

Grid-Forming Inverters as Synchronous Machine Replacements: Stability Analysis and Overcurrent Protection Strategies-MASTER THESIS ENGINEERING ELERTRICAL-MASTER CANDIDATE-ROBERTO NETO-Università di Padova 

 Abstract The increasing integration of renewable energy sources into power systems is driving the progressive replacement of traditional synchronous generators with power electronic converters. While essential for decarbonization, this shift leads to a significant reduction in system inertia, thereby compromising frequency stability and dynamic performance. Grid-forming inverters (GFMs) have emerged as a promising solution to these challenges, as they autonomously regulate voltage and frequency, effectively emulating the behavior of conventional synchronous machines. This thesis presents a comprehensive study of three major grid-forming control strategies: droop control, Virtual Synchronous Machine (VSM), and dispatchable Virtual Oscillator Control (dVOC). Each approach is evaluated based on its dynamic response and stability characteristics. Time-domain simulations are carried out in MATLAB/Simulink on a modified IEEE 9-bus test system. Scenarios include systems dominated by synchronous machines, mixedgeneration configurations, and grids with 100% inverter-based renewable sources. The results highlight the critical role of GFMs in enhancing frequency stability and grid resilience. In addition, the thesis includes detailed modeling of the inverters DC-side power supply, consisting of a photovoltaic plant coupled with a Hybrid Energy Storage System (HESS) based on batteries and supercapacitors. This configuration reflects realistic operating conditions and ensures stable power injection into the AC grid. Finally, the thesis explores protection mechanisms to mitigate overcurrent conditions during disturbances. These control strategies are vital to ensure the secure operation of GFMs under fault scenarios and to support the long-term reliability of renewable-based power systems.

FULL THESIS: https://thesis.unipd.it/retrieve/7da633d3-120d-48a3-ad52-76b2fc66574e/Tonet_Roberto.pdf