단상 반도체 변압기의 출력 전력 전향 보상을 통한 과도 응답 개선 = A Transient Response Improvement by Output Power Feedforward Compensation for Single-Phase Solid-State Transformer--Bang Jaehyeon Department of Electrical Engineering Graduate School of Konkuk University-

 

ABSTRACT 

A Transient Response Improvement by Output Power Feedforward Compensation for Single- Phase Solid-State Transformer Bang Jaehyeon

Department of Electrical Engineering Graduate School of Konkuk University 

This paper proposes a output power feedforward compensation method for Dual Active Bridge(DAB) converter based 2-stage single-phase solid-state transformer. Solid-State Transformer(SST) is a bidirectional power converter which is capable of electrical isolation between input and output stage. SST enables the connection of DC power sources such as PV panels, Fuel Cells, and ESS much easier compared with conventional transformers by forming DC bus. Each stage of SST composes of AC-DC converter and isolated DCDC converter. Especially, DAB converter, which has advantages of galvanic isolation with high frequency(HF) transformer, facility of bidirectional operation, and ease of realizing soft switching, is regarded as one of the most fundamental elements in SST. In contrast to conventional PWM converters, DAB converter controls output power by adjusting the phase shift between output voltage of two H-bridges. 70 For designing output voltage feedback controller, small signal model of DAB converter derived from output power equation with phase reference DAB d is applied. Also, bandwidth limitation caused by 120Hz power ripple in DC-link voltage controller, which induces unequal input and output voltage ratio compared with turns ratio of HF transformer, is described. For eliminating this voltage decoupling with current peak rising of leakage inductor, output power-based feedforward compensation method for DC-link voltage controller is proposed. Furthermore, the effectiveness of feedforward term is identified by confirming the reduction in output impedance of converter based on small signal model. In comparison of experimental results, proposed method verified the improvement in transient DC-link voltage decrease by 24.8% and leakage inductor current peak increase by 27.7% during load step input. It also yielded improvement in DC-link voltage increase by 23% while unload transient. Keyword : Solid-State Transformer(SST), Dual Active Bridge(DAB) converter

ORIGINAL LINK: http://www.riss.kr/search/detail/DetailView.do?p_mat_type=be54d9b8bc7cdb09&control_no=491adc48c7a349efffe0bdc3ef48d419&keyword=sst%20solid%20state%20transformer

ALTERNATIVE LINK: 

https://www.mediafire.com/file/6nohyto2co5zglz/A+Transient+Response+Improvement+by+Output+Power+Feedforward+Compensation+for+Single-Phase+Solid-State+Transformer.pdf/file

배터리 에너지 저장 시스템에 사용되는 전력 변환 시스템의 디지털 제어 Digital Control of Power Conversion System Used in Battery Energy Storage System-Wan, Kim Department of Marine Electronic, Communication and Computer Engineering, Graduate School, Mokpo National Maritime University

 Digital Control of Power Conversion System Used in Battery Energy Storage System

 BY Wan, Kim 

Department of Marine Electronic, Communication and Computer Engineering, Graduate School, Mokpo National Maritime University (Supervised by Professor : Kwang-Woon, Lee) 

ABSTRACT

To operate the electric power supply system more efficiently and stably, the utilization of battery energy storage system (BESS) is increasing. By using BESS, the residual electrical energy can be stored at low power demand times and the stored electrical energy can be released at high power demand times. Therefore, BESS can counteract the frequency fluctuation of the electric power system due to load variations. In addition, BESS can be utilized to make stable operation of renewable energy sources such as photovoltaic power generation and wind power generation. An electric power conversion system is used in BESS and it consists of bidirectional dc-to-dc converters and dc-to-ac inverters; the role of the bidirectional dc-to-dc converters is to charge and discharge the batteries and the dc-to-ac inverters are employed for grid connected energy conversion. A digital control is generally used to control the electric power conversion system of BESS and typical digital control strategy is based on the small signal model of the electric power conversion system. However, it is known that the small signal model based digital control is vulnerable to the operating point variations because the small signal model is obtained at a specific operating point. The purpose of this paper is to present a stable digital control strategy for the electric power conversion system of BESS, insensitive to operating point variations. This paper presents a design method for the power conversion system of BESS, wherein an average model based control is employed to solve the problem of the conventional small signal model based control. To compare the performance of the proposed control method with the conventional small signal model based controller, the single input and single output (SISO) controller design tool of MATLAB is utilized. For this purpose, the small signal model of the bidirectional dc-to-dc converter is derived and the SISO tool based digital controller is designed to obtain the specific bandwidth and phase margin. The time and frequency domain responses of the proposed average model based controller are obtained using a PSIM software and the obtained results are compared with the responses of the conventional small signal model based controller to show the improved transient control performance of the proposed method. To prove the effectiveness of the proposed method, the proposed control method is implemented using a digital signal processor (DSP).

VIEW FULL TEXT: 

https://www.mediafire.com/file/7sgipakydjok2ux/Digital+Control+of+Power+Conversion+System+Used+in+Battery+Energy+Storage+System.pdf/file

A comprehensive design approach for a three-winding planar transformer Shenli Zou1 Chanaka Singhabahu2 Jianfei Chen2 Alireza Khaligh2

A comprehensive design approach for a three-winding planar transformer 

Shenli Zou1 Chanaka Singhabahu2 Jianfei Chen2 Alireza Khaligh2 

1Electric Power Conversion, Rivian Automotive,

Inc, USA

2Maryland Power Electronics Laboratory (MPEL),

Department of Electrical and Computer

Engineering, Institute for Systems Research,

University of Maryland, College Park, Maryland,

USA

 Abstract 

In this paper, a new three-winding planar transformer design with the integrated leakage inductor is proposed for a triple-active-bridge converter. It enables two output voltage levels: a high voltage (HV) output port and a low voltage (LV) output port. The primary and secondary windings are split unevenly in both side legs while the tertiary winding is connected in parallel. The unique winding configuration enables: (i) enhanced efficiency with low volume; and (ii) suppressed parasitic capacitances. Detailed transformer reluctance and loss models are developed in the design process. The core geometry is optimized using a reluctance-model-based mathematical computation. Moreover, comprehensive high-fidelity simulations are conducted to analyse the trade-offs among parasitic capacitances, losses, and inductances. The customized core and the non-overlapping winding boards are assembled, characterized, and tested under various power flow conditions.

VIEW FULL TEXT

https://ietresearch.onlinelibrary.wiley.com/doi/full/10.1049/pel2.12261

Full-SiC Integrated Power Module Based on Planar Packaging Technology for High Efficiency Power Converters in Aircraft Applications O. Raab, M. Guacci, A. Griffo, K. Kriegel, M. Heller, J. Wang, D. Bortis, M. Schulz, J. W. Kolar

 

Proceedings of the 11th International Conference on Integrated Power Electronics Systems (CIPS 2020), Berlin, Germany, March 24-26, 2020 

Full-SiC Integrated Power Module Based on Planar Packaging Technology for High Efficiency Power Converters in Aircraft Applications O. Raab, M. Guacci, A. Griffo, K. Kriegel, M. Heller, J. Wang, D. Bortis, M. Schulz, J. W. Kolar 

Full-SiC Integrated Power Module based on Planar Packaging Technology for High Efficiency Power Converters in Aircraft Applications Oliver Raaba , Mattia Guaccib , Antonio Griffoc , Kai Kriegela , Morris Hellerb , Jiabin Wangc , Dominik Bortisb , Martin Schulza , and Johann W. Kolarb aSiemens AG, Corporate Technology, Munich, Germany bPower Electronic Systems Laboratory, ETH Zurich, Zurich, Switzerland cDepartment of Electronic and Electrical Engineering, The University of Sheffield, Sheffield, UK 

Abstract

 Compact, light-weight, efficient and reliable power converters are fundamental for the future of More Electrical Aircraft (MEA). Core elements supporting the electrification of the aerospace industry are power modules (PMs) employing exclusively SiC MOSFETs. In order to fully exploit the high switching speeds enabled by SiC, and to address the challenges arising from the parallelization of power devices, novel PM concepts must be investigated. In this paper, highly symmetrical layouts, low inductance planar interconnection technologies, and integrated buffer capacitors are explored to realize a high efficiency, fast-switching, and reliable full-SiC PM for MEA applications. A comprehensive assessment of a number of performance metrics against state-of-the-art full-SiC PMs demonstrates the benefits of the proposed design approach and manufacturing technologies. Moreover, by integrating temperature and current sensors, intelligent functions, which are crucial for the safe application of power electronics in MEA, are added to the developed PM. In this context, the use of MOSFETs’ Temperature Sensitive Electrical Parameters for online junction temperature estimation is demonstrated, allowing for non-invasive, i.e. without the need for dedicated sensors, thermal monitoring. Additionally, a highly compact gate driver, reducing the overall system volume and complexity, is designed and integrated in the housing of the PM. Finally, switching waveforms are measured during operation of the PM at 500V and 200A, proving the performance improvement enabled by the low inductance layout, the integrated snubber, and the gate driver.

VIEW FULL TEXT:

https://www.pes-publications.ee.ethz.ch/uploads/tx_ethpublications/8_CIPS-2020_Full-SiC-Integrated-Power-Module-based_FINAL-updated_Guacci.pdf

The MEGACube 166kW/20kHz Medium-Frequency Transformer

 

The MEGACube 166kW/20kHz Medium-Frequency Transformer 

ABSTRACT 

High power DC-DC conversion constitutes the key enabling technology for the implementation of solid-statetransformers. Within these high-power DC-DC converters, the Medium Frequency (MF) transformer is one of the main components, as its task is to provide the primary to secondary isolation and the step-up ratio between the different voltage levels. Several options for the construction of this MF transformer have been reported with different considered core materials, winding arrangements, isolation concepts and thermal management, whereby the main realizations will be revised in this paper. Thereafter, the details of a 166kW/20kHz MF transformer will be presented together with the designed test-bench utilized for the continuous testing of the transformer.

ORIGINAL LINK IN WEB:https://www.pes-publications.ee.ethz.ch/uploads/tx_ethpublications/01_MegaCube_Trafo_Digest_APEC2013.pdf