Model Predictive Control for Paralleled Uninterruptible Power Supplies with an Additional Inverter Leg for Load-Side Neutral Connection Tiago Oliveira , Luís Caseiro , André Mendes , Sérgio Cruz and Marina Perdigão Department of Electrical and Computer Engineering, University of Coimbra-

Abstract Uninterruptible Power Supplies (UPS) have been demonstrated to be the key technology in feeding either single- and three-phase loads in a wide range of critical applications, such as high-tier datacenters and medical facilities. To increase the overall system power capacity and resilience, UPS systems are usually connected in parallel. When UPS systems are parallel connected, a circulating current can rise, inhibiting correct system operation. Moreover, having a controlled load power distribution is another fundamental requirement in paralleled UPS systems. However, strategies to ensure these two topics have not been explored to date for UPS systems with a load-side neutral connection. This paper proposes an innovative Finite Control Set Model Predictive Control (FCS-MPC) strategy that ensures circulating current elimination and controlled load power distribution for paralleled UPS systems that use an additional inverter leg for load neutral point connection. Additionally, a system topology based on two parallel-connected UPS systems that can simultaneously supply single- and three-phase critical loads is proposed. Experimental results show the effectiveness and robustness of the proposed control techniques even when different types of loads are connected to the UPS systems. 

VIEW FULL TEXT WEB: https://www.mdpi.com/1996-1073/14/8/2270

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High-Power-Density GaN-Based Single-Phase Online Uninterruptible Power Supply Danish Shahzad, Nauman Zaffar*, Khurram K. Afridi Department of Electrical and Computer Engineering Cornell University Ithaca, New York, USA ds2358@cornell.edu, afridi@cornell.edu *Lahore University of Management Sciences Lahore, Pakistan

Abstract— This paper introduces a new topology suitable for a high-power-density single-phase online uninterruptible power supply (UPS) with a common neutral between its input and output ac ports while avoiding a split dc bus. The proposed topology enables high power density by utilizing half-bridge switch structures compatible with MHz-frequency operation. High efficiency is maintained in this converter by achieving soft-switching in rectifier stage with a boundary conduction mode control strategy. A comprehensive design methodology is developed to optimize the design of this converter. A 1-kVA prototype online UPS based on the proposed topology that utilizes GaN transistors and operates at switching frequencies up to 2 MHz is built and tested. The prototyped UPS achieves a power density of 26.4 W/in3.

 LINK:https://www.semanticscholar.org/paper/High-Power-Density-GaN-Based-Single-Phase-Online-Shahzad-Zaffar/4423c3c34e093b91970248d1de813d8db2016d91

Gallium Nitride Converters for Spacecraft Applications by Thomas Vernon Cook B.S. Electrical Engineering, University of Pittsburgh, 2017 Submitted to the Graduate Faculty of the Swanson School of Engineering in partial ful llment of the requirements for the degree of Master of Science University of Pittsburgh

 Gallium Nitride Converters for Spacecraft Applications by Thomas Vernon Cook B.S. Electrical Engineering, University of Pittsburgh, 2017 Submitted to the Graduate Faculty of the Swanson School of Engineering in partial fulllment of the requirements for the degree of Master of Science University of Pittsburgh

UNIVERSITY OF PITTSBURGH SWANSON SCHOOL OF ENGINEERING This thesis was presented by Thomas Vernon Cook It was defended on November 11, 2019 and approved by Dr. Brandon Grainger, PhD., Assistant Professor, Department of Electrical and Computer Engineering Dr. Alexis Kwasinski, PhD., Associate Professor, Department of Electrical and Computer Engineering Dr. Alan George, PhD., Department Chair, Department of Electrical and Computer Engineering Thesis Advisor: Dr. Brandon Grainger, PhD., Assistant Professor, Department of Electrical and Computer Engineering 

Gallium Nitride Converters for Spacecraft Applications by Thomas Vernon Cook B.S. Electrical Engineering, University of Pittsburgh, 2017 Submitted to the Graduate Faculty of the Swanson School of Engineering in partial fulllment of the requirements for the degree of Master of Science University of Pittsburgh.

LINK:https://d-scholarship.pitt.edu/37728/1/cooktv_etdPitt2019.pdf

Extending the Supply Voltage of a 600 V Input, No-Optocoupler Isolated Flyback Controller to 800 V or Higher-By Yuchen Yang, Senior Applications Engineer, and William Xiong, Applications Engineer, Analog Devices-MAGAZINE BODO POWER MARCH 2021

 Extending the Supply Voltage of a 600 V Input, No-Optocoupler Isolated Flyback Controller to 800 V or Higher 

By Yuchen Yang, Senior Applications Engineer,

and William Xiong, Applications Engineer, Analog Devices

In traditional isolated high voltage flyback converters, tight regulation is achieved using optocouplers to transfer regulation information from the secondary-side reference circuitry to the primary side. The problem is that optocouplers add significant complexity to isolated designs: there is propagation delay, aging, and gain variation, all of which complicate power supply loop compensation and can reduce reliability. By Yuchen Yang, Senior Applications Engineer, and William Xiong, Applications Engineer, Analog Devices

LINK: https://www.bodospower.com/default.aspx

Aleinik A.S., Vostrikov E.V., Volkovsky S.A., Deineka I.G., Strigalev V.E., Meshkovsky I.K. Fundamentals of circuitry of transceiving electronic devices: Study guide / Reviewer: Smirnova I.G. - St. Petersburg: ITMO University, 2021 .-- 149 p.

 А.С. Алейник, Е.В. Востриков, С.А. Волковский, И.Г. Дейнека, В.Е. Стригалев, И.К. Мешковский ОСНОВЫ СХЕМОТЕХНИКИ ПРИЕМОПЕРЕДАЮЩИХ ЭЛЕКТРОННЫХ УСТРОЙСТВ 

 Fundamentals of circuitry of transceiving electronic devices: Study guide / Reviewer: Smirnova IG Aleinik AS, Vostrikov EV, Volkovsky SA, Deineka IG, Strigalev VE, Meshkovsky IK Fundamentals of circuitry of transceiving electronic devices: Study guide / Reviewer: Smirnova IG - St. Petersburg: ITMO University, 2021 - 149 p. - copy.

 Annotation: The teaching aid presents the theoretical foundations of constructing circuits of current sources for the operation of LEDs and laser diodes in continuous, pulsed and high-frequency modes of operation. The schemes for switching on photodiodes with a description of the principle of their operation are given. Also, the parameters of electrical circuits of current sources are calculated and simulated in the free LTspice XVII electrical circuit simulator. The teaching aid is intended for theoretical (Chap. 1 and 2) and practical (Chap. 3) training of graduate students studying in the areas of training 04.16.01 Technical physics, 04.12.05 Laser technology and laser technologies. Description: Recommended for use at ITMO University in the field of training 04/12/05, 04/16/01 as a teaching aid for the implementation of the main professional educational programs of higher education for the magistracy. PDF: 

Title: Fundamentals of transceiver circuitry Download PDF (6971.38 Kb)

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