Energies

Research

25 pages, 6384 KiB

Open AccessArticle

The Conceptual Research over Low-Switching Modulation Strategy for Matrix Converters with the Coupled Reactors

by Pawel Szczepankowski, Jaroslaw Luszcz, Alexander Usoltsev, Natalia Strzelecka and Enrique Romero-Cadaval

Energies 2021, 14(3), 675; https://doi.org/10.3390/en14030675 - 28 Jan 2021

Viewed by 1511

Abstract

In this paper, different Pulse Width Modulation (PWM) strategies for operating with a low-switching frequency, a topology that combines Conventional Matrix Converters (CMCs), and Coupled Reactors (CRs) are presented and discussed. The principles of the proposed strategies are first discussed by a conceptual [...] Read more.

In this paper, different Pulse Width Modulation (PWM) strategies for operating with a low-switching frequency, a topology that combines Conventional Matrix Converters (CMCs), and Coupled Reactors (CRs) are presented and discussed. The principles of the proposed strategies are first discussed by a conceptual analysis and later validated by simulation. The paper shows how the combination of CMCs and CRs could be of special interest for sharing the current among these converters’ modules, being possible to scale this solution to be a modular system. Therefore, the use of coupled reactors allows one to implement phase shifters that give the solution the ability to generate a stair-case load voltage with the desired power quality even the matrix converters are operated with a low-switching frequency close to the grid frequency. The papers also address how the volume and weight of the coupled reactors decrease with the growth of the fundamental output frequency, making this solution especially appropriate for high power applications that are supplied at high AC frequencies (for example, in airport terminals, where a supply of 400 Hz is required). Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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20 pages, 5923 KiB

Open AccessArticle

A New Approach to the PWM Modulation for the Multiphase Matrix Converters Supplying Loads with Open-End Winding

by Pawel Szczepankowski, Natalia Strzelecka and Enrique Romero-Cadaval

Energies 2021, 14(2), 466; https://doi.org/10.3390/en14020466 - 17 Jan 2021

Cited by 1 | Viewed by 1916

Abstract

This article presents three variants of the Pulse Width Modulation (PWM) for the Double Square Multiphase type Conventional Matrix Converters (DSM-CMC) supplying loads with the open-end winding. The first variant of PWM offers the ability to obtain zero value of the common-mode voltage [...] Read more.

This article presents three variants of the Pulse Width Modulation (PWM) for the Double Square Multiphase type Conventional Matrix Converters (DSM-CMC) supplying loads with the open-end winding. The first variant of PWM offers the ability to obtain zero value of the common-mode voltage at the load’s terminals and applies only six switches within the modulation period. The second proposal archives for less Total Harmonic Distortion (THD) of the generated load voltage. The third variant of modulation concerns maximizing the voltage transfer ratio, minimizing the number of switching, and the common-mode voltage cancellation. The discussed modulations are based on the concept of sinusoidal voltage quadrature signals, which can be an effective alternative to the classic space-vector approach. In the proposed approach, the geometrical arrangement of basic vectors needed to synthesize output voltages is built from the less number of vectors, which is equal to the number of the matrix converter’s terminals. The PWM duty cycle computation is performed using only a second-order determinant of the voltages coordinate matrix without using trigonometric functions. A new approach to the PWM duty cycles computing and the load voltage synthesis by 5 × 5 and 12 × 12 topologies has been verified using the PSIM simulation software. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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16 pages, 5490 KiB

Open AccessArticle

Application of Grasshopper Optimization Algorithm for Selective Harmonics Elimination in Low-Frequency Voltage Source Inverter

by Marcin Steczek, Włodzimierz Jefimowski and Adam Szeląg

Energies 2020, 13(23), 6426; https://doi.org/10.3390/en13236426 - 4 Dec 2020

Cited by 18 | Viewed by 2491

Abstract

In this paper, an application of the recently developed Grasshopper Optimization Algorithm (GOA) for calculation of switching angles for Selective Harmonic Elimination (SHE) PWM in low-frequency voltage source inverter is proposed. The algorithm is based on insect behavior in the food foraging swarm [...] Read more.

In this paper, an application of the recently developed Grasshopper Optimization Algorithm (GOA) for calculation of switching angles for Selective Harmonic Elimination (SHE) PWM in low-frequency voltage source inverter is proposed. The algorithm is based on insect behavior in the food foraging swarm of grasshoppers. The characteristic feature of GOA is the movement of agents is based on the position of all agents in the swarm. This method represents a higher probability of convergence than Particle Swarm Optimization (PSO) Modifications of GOA have been examined regarding their effect on the algorithm’s convergence. The proposed modifications were based on the following techniques: Grey Wolf Optimizer (GWO), Natural Selection (NS), Adaptive Grasshopper Optimization Algorithm (AGOA), and Opposite Based Learning (OBL). The performance of GOA and its modifications were compared with well-known PSO. Areas, where GOA is superior to PSO in terms of probability of convergence, have been shown. The efficiency of the GOA algorithm applied for solving the SHE problem was confirmed by measurements in the laboratory. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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21 pages, 8763 KiB

Open AccessArticle

GaN-Based DC-DC Resonant Boost Converter with Very High Efficiency and Voltage Gain Control

by Zbigniew Waradzyn, Robert Stala, Andrzej Mondzik, Aleksander Skała and Adam Penczek

Energies 2020, 13(23), 6403; https://doi.org/10.3390/en13236403 - 3 Dec 2020

Cited by 14 | Viewed by 3814

Abstract

This paper presents a concept for the operation of a resonant DC–DC switched-capacitor converter with very high efficiency and output voltage regulation. In its basic concept, such a converter operates as a switched-capacitor voltage doubler (SCVD) in the Zero Current Switching (ZCS) mode [...] Read more.

This paper presents a concept for the operation of a resonant DC–DC switched-capacitor converter with very high efficiency and output voltage regulation. In its basic concept, such a converter operates as a switched-capacitor voltage doubler (SCVD) in the Zero Current Switching (ZCS) mode with a constant output voltage. The proposed methods of switching allow for the switched-capacitor (SC) converter output voltage regulation, and improve its efficiency by the operation with Zero Voltage Switching (ZVS). In this paper, various switching patterns are proposed to achieve high efficiency and the output voltage control by frequency or duty cycle regulation. Some examples of the application of the proposed switching patterns are presented: in current control at the start-up of the converter, in a bi-directional converter, and in a modular cascaded system. The paper also presents an analytical model as well as the relationships between the switching frequency, voltage ratio and efficiency. Further, it demonstrates the experimental verification of the waveforms, voltage ratios, as well as efficiency. The proposed experimental setup achieved a maximum efficiency of 99.228%. The implementation of the proposed switching patterns with the ZVS operation along with the GaN-based (Gallium Nitride) design, with a planar choke, leads to a high-efficiency and low-volume solution for the SCVD converter and is competitive with the switch-mode step-up converters. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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27 pages, 4069 KiB

Open AccessArticle

The Unified Power Quality Conditioner Control Method Based on the Equivalent Conductance Signals of the Compensated Load

by Andrzej Szromba

Energies 2020, 13(23), 6298; https://doi.org/10.3390/en13236298 - 29 Nov 2020

Cited by 13 | Viewed by 2101

Abstract

This paper proposes a new control method for a Unified Power Quality Conditioner (UPQC). This method is based on the load equivalent conductance approach, originally proposed by Fryze. It can be useful not only for compensation for nonactive current and for improving voltage [...] Read more.

This paper proposes a new control method for a Unified Power Quality Conditioner (UPQC). This method is based on the load equivalent conductance approach, originally proposed by Fryze. It can be useful not only for compensation for nonactive current and for improving voltage quality, but it also allows one to perform some unconventional functions. This control method can be performed by extending the orthodox notion of ‘static’ load equivalent conductance into a time-variable signal. It may be used to characterize energy changes in the whole UPQC-and-load circuitry. The UPQC can regulate energy flow between all sources and loads being under compensation. They may be located as well for UPQC’s AC-side as DC-side. System works properly even if they switch their activity to work either as loads or generators. The UPQC can operate also as a buffer, which can store/share the in-load generated energy amongst other loads, or it can transmit this energy to the source. Therefore, in addition to performing the UPQC’s conventional compensation tasks, it can also serve as a local energy distribution center. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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12 pages, 4444 KiB

Open AccessArticle

Suppression of Supply Current Harmonics of 18-Pulse Diode Rectifier by Series Active Power Filter with LC Coupling

by Wojciech Sleszynski, Artur Cichowski and Piotr Mysiak

Energies 2020, 13(22), 6060; https://doi.org/10.3390/en13226060 - 19 Nov 2020

Cited by 14 | Viewed by 1963

Abstract

The reported research aims at improving the quality of three-phase rectifier supply currents. An effective method consists of adding properly formed booster voltages to the fundamental supply voltages using a series active filter. In the proposed solution, the booster voltages are generated by [...] Read more.

The reported research aims at improving the quality of three-phase rectifier supply currents. An effective method consists of adding properly formed booster voltages to the fundamental supply voltages using a series active filter. In the proposed solution, the booster voltages are generated by three single-phase systems consisting of inverters, LC filters, and single-phase transformers. The application of LC couplings ensures low emission of disturbances, but may provoke compensator stability problems. The article presents the current control system for a series active filter designed to suppress the dominant harmonics in the supply currents of an 18-pulse rectifier, without interference into fundamental current components. A proportional control is proposed in combination with integral terms implemented in the orthogonal coordinate systems, which synchronically rotate with frequencies equal to those of the harmonic components to be eliminated. The use of complex gains in integral terms allows a simple phase correction of the output signals. A description is given of the method to determine controller parameters based on the mathematical model of the control object. Sample results of experimental tests performed in steady-state and transient conditions are included to illustrate the quality of performance of the series active filter as compared to the results recorded for the rectifier alone, and for the rectifier with additional line reactor. The applied control method of active filter significantly reduces harmonic distortion of the grid current, which is particularly advantageous at nonideal supply voltage and low loads. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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22 pages, 11887 KiB

Open AccessArticle

DC-DC High-Voltage-Gain Converters with Low Count of Switches and Common Ground

by Robert Stala, Zbigniew Waradzyn and Szymon Folmer

Energies 2020, 13(21), 5657; https://doi.org/10.3390/en13215657 - 29 Oct 2020

Cited by 4 | Viewed by 2192

Abstract

This paper presents a new concept and research results of DC-DC high-voltage-gain, high-frequency step-up resonant converters. The proposed topologies are optimized towards minimizing the number of switches and improvements in efficiency. Another relevant advantage of such type of converters is that they have [...] Read more.

This paper presents a new concept and research results of DC-DC high-voltage-gain, high-frequency step-up resonant converters. The proposed topologies are optimized towards minimizing the number of switches and improvements in efficiency. Another relevant advantage of such type of converters is that they have a common input and output negative point. The proposed converters are based on the resonant switched-capacitor voltage multiplier circuit, and that is why they are compared with a classic converter from this family. The included results show the operating principle, possible switching methods with the consideration of their impact on the voltage gain level, as well as the voltage and current ripples. The operating concepts and analytical calculations are confirmed by simulation and experimental results. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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30 pages, 10549 KiB

Open AccessArticle

SiC-Based Power Electronic Traction Transformer (PETT) for 3 kV DC Rail Traction

by Marek Adamowicz and Janusz Szewczyk

Energies 2020, 13(21), 5573; https://doi.org/10.3390/en13215573 - 24 Oct 2020

Cited by 17 | Viewed by 5228

Abstract

The design of rolling stock plays a key role in the attractiveness of the rail transport. Train design must strictly meet the requirements of rail operators to ensure high quality and cost-effective services. Semiconductor power devices made from silicon carbide (SiC) have reached [...] Read more.

The design of rolling stock plays a key role in the attractiveness of the rail transport. Train design must strictly meet the requirements of rail operators to ensure high quality and cost-effective services. Semiconductor power devices made from silicon carbide (SiC) have reached a level of technology enabling their widespread use in traction power converters. SiC transistors offering energy savings, quieter operation, improved reliability and reduced maintenance costs have become the choice for the next-generation railway power converters and are quickly replacing the IGBT technology which has been used for decades. The paper describes the design and development of a novel SiC-based DC power electronic traction transformer (PETT) intended for electric multiple units (EMUs) operated in 3 kV DC rail traction. The details related to the 0.5 MVA peak power medium voltage prototype, including the electrical design of the main building blocks are presented in the first part of the paper. The second part deals with the implementation of the developed SiC-based DC PETT into a regional train operating on a 3 kV DC traction system. The experimental results obtained during the testing are presented to demonstrate the performance of the developed 3 kV DC PETT prototype. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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17 pages, 4661 KiB

Open AccessArticle

Dielectric Barrier Discharge Systems with HV Generators and Discharge Chambers for Surface Treatment and Decontamination of Organic Products

by Jan Mucko, Robert Dobosz and Ryszard Strzelecki

Energies 2020, 13(19), 5181; https://doi.org/10.3390/en13195181 - 5 Oct 2020

Cited by 4 | Viewed by 2673

Abstract

The article presents applications of systems with power electronic converters, high voltage transformers, and discharge chambers used for nonthermal, dielectric barrier discharge plasma treatment of a plastic surface and decontamination of organic loose products. In these installations, the inductance of the high voltage [...] Read more.

The article presents applications of systems with power electronic converters, high voltage transformers, and discharge chambers used for nonthermal, dielectric barrier discharge plasma treatment of a plastic surface and decontamination of organic loose products. In these installations, the inductance of the high voltage transformers and the capacitances of the electrode sets form resonant circuits that are excited by inverters. The article presents characteristic features of the installations and basic mathematical relationships as well as the impact of individual parameters of system components. These converters with their output installations were designed, built, and tested by the authors. Some of the converters developed by the authors are manufactured and used in the industry. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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13 pages, 2890 KiB

Open AccessArticle

Adaptive Maximum Torque per Ampere Control of Sensorless Permanent Magnet Motor Drives

by Anton Dianov and Alecksey Anuchin

Energies 2020, 13(19), 5071; https://doi.org/10.3390/en13195071 - 27 Sep 2020

Cited by 25 | Viewed by 3180

Abstract

Interior permanent magnet synchronous motor (IPMSM) efficiency can be improved by using maximum torque per ampere control (MTPA). MTPA control utilizes both alignment and reluctance torques and usually requires information about the magnetization map of the electrical machine. This paper proposes an adaptive [...] Read more.

Interior permanent magnet synchronous motor (IPMSM) efficiency can be improved by using maximum torque per ampere control (MTPA). MTPA control utilizes both alignment and reluctance torques and usually requires information about the magnetization map of the electrical machine. This paper proposes an adaptive MTPA algorithm for sensorless control systems of IPMSM drives, which is applicable in industrial and commercial drives. This algorithm enhances conventional control schemes, where the output of the speed controller is the commanded stator current and the direct current is calculated using an MTPA equation; therefore, it can be easily implemented in the previously developed drives. The proposed algorithm does not use any motor parameters for the calculation of the MTPA trajectory, which is important for systems operating in changing environmental conditions, because motor inductances and flux linkage strongly depend on the stator current and the rotor temperature, respectively. The proposed algorithm continuously varies the current phase and in such a way it tries to minimize the magnitude of the stator current at the applied load torque. The main contribution of this paper is the development of a technique to overcome the main disadvantage of seeking algorithms–the necessity of a precision information about the rotor position. The proposed method was verified experimentally. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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17 pages, 13242 KiB

Open AccessArticle

Unidirectional DC/DC Converter with Voltage Inverter for Fast Charging of Electric Vehicle Batteries

by Jerzy Ryszard Szymanski, Marta Zurek-Mortka, Daniel Wojciechowski and Nikolai Poliakov

Energies 2020, 13(18), 4791; https://doi.org/10.3390/en13184791 - 14 Sep 2020

Cited by 18 | Viewed by 4830

Abstract

The paper proposes the adaptation of the industrial plant’s power network to supply electric vehicle (EV) fast-charging converters (above 300 kW) using renewable energy sources (RESs). A 600 V DC microgrid was used to supply energy from RESs for the needs of variable [...] Read more.

The paper proposes the adaptation of the industrial plant’s power network to supply electric vehicle (EV) fast-charging converters (above 300 kW) using renewable energy sources (RESs). A 600 V DC microgrid was used to supply energy from RESs for the needs of variable speed motor drives and charging of EV batteries. It has been shown that it is possible to support the supply of drive voltage frequency converters (VFCs) and charging of EV batteries converters with renewable energy from a 600 V DC microgrid, which improves the power quality indicators in the power system. The possibility of implementing the fast EV batteries charging station to the industrial plant’s power system in such a way that the system energy demand is not increased has also been shown. The EV battery charging station using the drive converter has been presented, as well as the results of simulation and laboratory tests of the proposed solution. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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16 pages, 10147 KiB

Open AccessArticle

Feasibility Study GaN Transistors Application in the Novel Split-Coils Inductive Power Transfer System with T-Type Inverter

by Viktor Shevchenko, Bohdan Pakhaliuk, Oleksandr Husev, Oleksandr Veligorskyi, Deniss Stepins and Ryszard Strzelecki

Energies 2020, 13(17), 4535; https://doi.org/10.3390/en13174535 - 1 Sep 2020

Cited by 5 | Viewed by 2280

Abstract

A promising solution for inductive power transfer and wireless charging is presented on the basis of a single-phase three-level T-type Neutral Point Clamped GaN-based inverter with two coupled transmitting coils. The article focuses on the feasibility study of GaN transistor application in the [...] Read more.

A promising solution for inductive power transfer and wireless charging is presented on the basis of a single-phase three-level T-type Neutral Point Clamped GaN-based inverter with two coupled transmitting coils. The article focuses on the feasibility study of GaN transistor application in the wireless power transfer system based on the T-type inverter on the primary side. An analysis of power losses in the main components of the system is performed: semiconductors and magnetic elements. System modeling was performed using Power Electronics Simulation Software (PSIM). It is shown that the main losses of the system are static losses in the filter inductor and rectifier diodes on the secondary side, while GaN transistors can be successfully used for the wireless power transfer system. The main features of the Printed Circuit Board (PCB) design of GaN transistors are considered in advance. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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17 pages, 6351 KiB

Open AccessArticle

Hybrid Modulation for Modular Voltage Source Inverters with Coupled Reactors

by Krzysztof Jakub Szwarc, Pawel Szczepankowski, Janusz Nieznański, Cezary Swinarski, Alexander Usoltsev and Ryszard Strzelecki

Energies 2020, 13(17), 4450; https://doi.org/10.3390/en13174450 - 27 Aug 2020

Cited by 2 | Viewed by 2583

Abstract

This paper proposes and discusses a concept of a hybrid modulation for the control of modular voltage source inverters with coupled reactors. The use of coupled reactors as the integrating elements leads to significant reduction in the size and weight of the circuit. [...] Read more.

This paper proposes and discusses a concept of a hybrid modulation for the control of modular voltage source inverters with coupled reactors. The use of coupled reactors as the integrating elements leads to significant reduction in the size and weight of the circuit. The proposed modulation combines novel coarsely quantized pulse amplitude modulation (CQ-PAM) and innovative space-vector pulse width modulation (SVPWM). The former enjoys very low transistor switching frequency and low harmonic elimination, while the latter ensures high resolution of amplitude control. The SVPWM is based on the use of barycentric coordinates. The feasibility of the proposed solution is verified by simulations and laboratory tests of a 12-pulse modular voltage source inverters with two-level and three-level component inverters. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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9 pages, 9115 KiB

Open AccessArticle

Aggregated Conducted Electromagnetic Interference Generated by DC/DC Converters with Deterministic and Random Modulation

by Hermes Loschi, Robert Smolenski, Piotr Lezynski, Douglas Nascimento and Galina Demidova

Energies 2020, 13(14), 3698; https://doi.org/10.3390/en13143698 - 21 Jul 2020

Cited by 9 | Viewed by 2939

Abstract

The assessment of electromagnetic compatibility (EMC) is important for both technical and legal reasons. This manuscript addresses specific issues that should be taken into account for proper EMC assessment of energy systems that use power electronic interfaces. The standardized EMC measuring techniques have [...] Read more.

The assessment of electromagnetic compatibility (EMC) is important for both technical and legal reasons. This manuscript addresses specific issues that should be taken into account for proper EMC assessment of energy systems that use power electronic interfaces. The standardized EMC measuring techniques have been used in a laboratory setup consisting in two identical DC/DC converters with deterministic and random modulations. Measuring difficulties caused by the low frequency envelopes, resulting from frequency beating accompanying aggregation of harmonic components of similar frequencies, were indicated as a phenomenon that might lead to significant problems during the EMC assessment using currently binding standards. The experimental results describing deterministic and random modulated converters might be useful for practitioners implementing power interfaces in microgrids and power systems as well as for researchers involved in EMC assurance of power systems consisting in multiple power electronic interfaces. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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24 pages, 22073 KiB

Open AccessArticle

Fault Diagnosis of PMSG Stator Inter-Turn Fault Using Extended Kalman Filter and Unscented Kalman Filter

by Waseem El Sayed, Mostafa Abd El Geliel and Ahmed Lotfy

Energies 2020, 13(11), 2972; https://doi.org/10.3390/en13112972 - 9 Jun 2020

Cited by 38 | Viewed by 3677

Abstract

Since the permeant magnet synchronous generator (PMSG) has many applications in particular safety-critical applications, enhancing PMSG availability has become essential. An effective tool for enhancing PMSG availability and reliability is continuous monitoring and diagnosis of the machine. Therefore, designing a robust fault diagnosis [...] Read more.

Since the permeant magnet synchronous generator (PMSG) has many applications in particular safety-critical applications, enhancing PMSG availability has become essential. An effective tool for enhancing PMSG availability and reliability is continuous monitoring and diagnosis of the machine. Therefore, designing a robust fault diagnosis (FD) and fault tolerant system (FTS) of PMSG is essential for such applications. This paper describes an FD method that monitors online stator winding partial inter-turn faults in PMSGs. The fault appears in the direct and quadrature (dq)-frame equations of the machine. The extended Kalman filter (EKF) and unscented Kalman filter (UKF) were used to detect the percentage and the place of the fault. The proposed techniques have been simulated for different fault scenarios using Matlab^®/Simulink^®. The results of the EKF estimation responses simulation were validated with the practical implementation results of tests that were performed with a prototype PMSG used in the Arab Academy For Science and Technology (AAST) machine lab. The results showed impressive responses with different operating conditions when exposed to different fault states to prevent the development of complete failure. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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16 pages, 3141 KiB

Open AccessArticle

SiC-Based Bidirectional Multilevel High-Voltage Gain Switched-Capacitor Resonant Converter with Improved Efficiency

by Adam Kawa and Robert Stala

Energies 2020, 13(10), 2445; https://doi.org/10.3390/en13102445 - 13 May 2020

Cited by 11 | Viewed by 2990

Abstract

This paper presents the research results of the bidirectional multilevel resonant switched capacitor converter (MRSCC). The converter can achieve a high voltage ratio in multilevel topology, which limits the voltage stress on switches and is able to operate with high power efficiency. The [...] Read more.

This paper presents the research results of the bidirectional multilevel resonant switched capacitor converter (MRSCC). The converter can achieve a high voltage ratio in multilevel topology, which limits the voltage stress on switches and is able to operate with high power efficiency. The converter can be applied as an interconnector between DC voltage systems used for various applications. This paper presents a method that significantly improves the efficiency of the MSRCC through topology modification. Furthermore, the feasibility of the converter was demonstrated with the use of SiC and Si MOSFET switches, together with suitable passive components. It was demonstrated that the proposed modification of the topology makes the converter very efficient in SiC-based ones and can significantly improve the efficiency of Si MOSFET converters. The series of test results of the SiC-based converter is a novel aspect presented in this paper and shows promising achievements of efficiency. The results were obtained from the laboratory setup of 5 kW and 0.5/2 kV MRSCC. To demonstrate the bidirectional operation of the converter, a back-to-back setup (0.5/2/0.5 kV) was used. It also demonstrates that such a high-voltage gain converter can be accurately tested with the use of laboratory equipment with a typical voltage range. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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14 pages, 4262 KiB

Open AccessArticle

FPGA-Based System for Electromagnetic Interference Evaluation in Random Modulated DC/DC Converters

by Hermes Loschi, Piotr Lezynski, Robert Smolenski, Douglas Nascimento and Wojciech Sleszynski

Energies 2020, 13(9), 2389; https://doi.org/10.3390/en13092389 - 11 May 2020

Cited by 20 | Viewed by 4477

Abstract

Field-Programmable Gate Array (FPGA) provides the possibility to design new “electromagnetic compatibility (EMC) friendly” control techniques for power electronic converters. Such control techniques use pseudo-random modulators (RanM) to control the converter switches. However, some issues connected with the FPGA-based design of RanM, such [...] Read more.

Field-Programmable Gate Array (FPGA) provides the possibility to design new “electromagnetic compatibility (EMC) friendly” control techniques for power electronic converters. Such control techniques use pseudo-random modulators (RanM) to control the converter switches. However, some issues connected with the FPGA-based design of RanM, such as matching the range of fixed-point numbers, might be challenging. The modern programming tools, such as LabVIEW, may facilitate the design process, but there are still fixed-point operations and limitations in arithmetic operations. This paper presents the design insights on the FPGA-based EMC friendly control system for DC/DC converter. Probability density functions (PDF) are used to analyse and improve pseudo-random algorithms. The theoretical algorithms, hardware details and experimental results are presented and discussed in terms of conducted electromagnetic interference emission. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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21 pages, 10527 KiB

Open AccessArticle

Effective Permeability of Multi Air Gap Ferrite Core 3-Phase Medium Frequency Transformer in Isolated DC-DC Converters

by Piotr Dworakowski, Andrzej Wilk, Michal Michna, Bruno Lefebvre, Fabien Sixdenier and Michel Mermet-Guyennet

Energies 2020, 13(6), 1352; https://doi.org/10.3390/en13061352 - 14 Mar 2020

Cited by 11 | Viewed by 5657

Abstract

The magnetizing inductance of the medium frequency transformer (MFT) impacts the performance of the isolated dc-dc power converters. The ferrite material is considered for high power transformers but it requires an assembly of type “I” cores resulting in a multi air gap structure [...] Read more.

The magnetizing inductance of the medium frequency transformer (MFT) impacts the performance of the isolated dc-dc power converters. The ferrite material is considered for high power transformers but it requires an assembly of type “I” cores resulting in a multi air gap structure of the magnetic core. The authors claim that the multiple air gaps are randomly distributed and that the average air gap length is unpredictable at the industrial design stage. As a consequence, the required effective magnetic permeability and the magnetizing inductance are difficult to achieve within reasonable error margins. This article presents the measurements of the equivalent B(H) and the equivalent magnetic permeability of two three-phase MFT prototypes. The measured equivalent B(H) is used in an FEM simulation and compared against a no load test of a 100 kW isolated dc-dc converter showing a good fit within a 10% error. Further analysis leads to the demonstration that the equivalent magnetic permeability and the average air gap length are nonlinear functions of the number of air gaps. The proposed exponential scaling function enables rapid estimation of the magnetizing inductance based on the ferrite material datasheet only. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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17 pages, 3446 KiB

Open AccessArticle

A Parallel Estimation System of Stator Resistance and Rotor Speed for Active Disturbance Rejection Control of Six-Phase Induction Motor

by Hamidreza Heidari, Anton Rassõlkin, Mohammad Hosein Holakooie, Toomas Vaimann, Ants Kallaste, Anouar Belahcen and Dmitry V. Lukichev

Energies 2020, 13(5), 1121; https://doi.org/10.3390/en13051121 - 2 Mar 2020

Cited by 14 | Viewed by 2742

Abstract

In this paper, a parallel estimation system of the stator resistance and the rotor speed is proposed in speed sensorless six-phase induction motor (6PIM) drive. First, a full-order observer is presented to provide the stator current and the rotor flux. Then, an adaptive [...] Read more.

In this paper, a parallel estimation system of the stator resistance and the rotor speed is proposed in speed sensorless six-phase induction motor (6PIM) drive. First, a full-order observer is presented to provide the stator current and the rotor flux. Then, an adaptive control law is designed using the Lyapunov stability theorem to estimate the rotor speed. In parallel, a stator resistance identification scheme is proposed using more degrees of freedom of the 6PIM, which is also based on the Lyapunov stability theorem. The main advantage of the proposed method is that the stator resistance adaptation is completely decoupled from the rotor speed estimation algorithm. To increase the robustness of the drive system against external disturbances, noises, and parameter uncertainties, an active disturbance rejection controller (ADRC) is introduced in direct torque control (DTC) of the 6PIM. The experimental results clarify the effectiveness of the proposed approaches. Full article

(This article belongs to the Special Issue Industrial and Technological Applications of Power Electronics Systems)

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