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Efficiency Improvement of Flying-Capacitor Linear Amplifier by Unequal Capacitor Voltage Ratio 利用不等电容电压比提高飞电容线性放大器效率
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9807187
H. Obara, Keiichi Matsushima
{"title":"Efficiency Improvement of Flying-Capacitor Linear Amplifier by Unequal Capacitor Voltage Ratio","authors":"H. Obara, Keiichi Matsushima","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9807187","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9807187","url":null,"abstract":"This paper proposes a flying-capacitor linear amplifier (FCLA) with unequal capacitor voltages to realize higher efficiency and low electromagnetic interference. The efficiency of the FCLA can be improved by increasing the number of series MOSFETs. However, it causes a higher cost of the MOSFETs and gate drivers. In this paper, it is clarified that the efficiency can be improved by defining the voltage values of each flying-capacitor properly even in the same numbers of MOSFETs. The effectiveness of the proposed method is evaluated and compared to other topologies of the multilevel linear amplifier. It has been clarified that the efficiency of the proposed FCLA can be improved, especially when the number of devices is small and modulation factor is high. The result of this paper is useful for design and implementation of multilevel-topology-based linear amplifiers with higher efficiency and lower noise.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128533645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Impact of DC-Link Voltage Control on Transient Stability of PLL-Synchronized Voltage-Source Converters 直流链路电压控制对锁相同步电压源变换器暂态稳定性的影响
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9807084
Teng Liu, Xiongfei Wang, Fangcheng Liu
{"title":"Impact of DC-Link Voltage Control on Transient Stability of PLL-Synchronized Voltage-Source Converters","authors":"Teng Liu, Xiongfei Wang, Fangcheng Liu","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9807084","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9807084","url":null,"abstract":"This article analyzes the impact of dc-link voltage control on the transient stability of voltage-source converters (VSCs) with the phase-locked loop (PLL) based synchronization. By integrating the dynamic of the dc-link voltage control into that of PLL, a fourth-order nonlinear large-signal model, which represents the dynamic behavior of the synchronism under large disturbances, is established. Further, the transient stability of the PLL-synchronized VSC is evaluated by using phase portraits. It is revealed that, compared to the case with a constant dc-link voltage, the dc-link voltage control would jeopardize the transient stability of the PLL-synchronized VSC, especially in the weak grid condition. Next, the parametric effects of the dc-link voltage control on the transient stability are demonstrated, which shed clear insights into the controller design to enhance the transient stability of VSCs. Lastly, all the theoretical findings are validated by the experimental tests.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124547414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
Study on Interconnecting Operation Control of Electronic Frequency Converters Realizing the Replacement of All Rotary Frequency Changers in Nishisagami Substation in the Tokaido Shinkansen 东海道新干线西上变电所实现全旋转变频器更换的电子变频器互连运行控制研究
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9807245
T. Shimizu, K. Kunomura, Hiroki Miyajima, Takumi Nagai
{"title":"Study on Interconnecting Operation Control of Electronic Frequency Converters Realizing the Replacement of All Rotary Frequency Changers in Nishisagami Substation in the Tokaido Shinkansen","authors":"T. Shimizu, K. Kunomura, Hiroki Miyajima, Takumi Nagai","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9807245","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9807245","url":null,"abstract":"Rotary frequency changers (RFCs) have been used since the 1960s as frequency converters applied to high-speed railway's AC power supplies, and the RFCs still play a major role today. On the other hand, electronic frequency converters (EFCs), which have advantages compared to RFCs in terms of maintenance cost and energy saving, have been introduced, and we have been working to increase the installation ratio of EFCs. As a result of this progress, we have reached a stage where we need to reduce the number of frequency conversion substations (FC-SSs) that require RFCs, if we intend to further increase the installation ratio of EFCs. Under this situation, we studied a new interconnection control technology to realize the interconnection operation with the existing remote power supply systems, in order to replace all RFCs with EFCs at the Nishisagami FC-SS of the Tokaido Shinkansen.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124792425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Maximum Torque per Ampere Control of IPMSM Using Online Flux Linkage Plane Estimation Considering Cross Saturation 考虑交叉饱和的在线磁链平面估计的IPMSM每安培最大转矩控制
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9806964
Suzuka Sasayama, Yuki Shimizu, S. Morimoto, Y. Inoue, M. Sanada
{"title":"Maximum Torque per Ampere Control of IPMSM Using Online Flux Linkage Plane Estimation Considering Cross Saturation","authors":"Suzuka Sasayama, Yuki Shimizu, S. Morimoto, Y. Inoue, M. Sanada","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9806964","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9806964","url":null,"abstract":"Interior permanent magnet synchronous motors (IPMSMs) are used for various applications and high efficiency control is required. Maximum torque per ampere (MTPA) control is one of the methods to control IPMSMs with high efficiency. Because the motor parameters vary with magnetic saturation, MTPA control cannot be easily realized. Here, we propose a fully online and automatic MTPA control method. To find the MTPA point while driving the motor, it is necessary to predict the entire flux linkage surface. Therefore, the flux linkage surface is approximated by a plane from the sensor information at a specific current condition that considers the effect of magnetic cross saturation. The MTPA control is achieved using the estimated flux linkage plane and the gradient ascent method. The simulation results showed that the torque was maximized in two search periods, which was completed in 0.06 s. The proposed method was effective for a wide current range.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"89 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129743445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Imbalanced Force Suppression Due to Static Eccentricity by Using Triple Three-phase Winding Motor 用三相绕组电机抑制静偏心引起的不平衡力
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9807101
Kan Yang, K. Akatsu, Kodai Okazaki, Y. Miyama
{"title":"Imbalanced Force Suppression Due to Static Eccentricity by Using Triple Three-phase Winding Motor","authors":"Kan Yang, K. Akatsu, Kodai Okazaki, Y. Miyama","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9807101","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9807101","url":null,"abstract":"Permanent magnet synchronous machines (PMSMs) are widely used in a variety of applications. Static eccentricity of rotor is a common fault at the fabrication process. These faults cause imbalanced electromagnetic force and exert unexpected vibration at the design process. This research investigates the impact of this fault on the temporal and spatial harmonic distribution of electromagnetic force. Moreover, a compensation method has been proposed to suppress imbalanced force caused due to static eccentricity by using triple three phase winding motor. The system of triple three phase winding motor relies on three independent sets of windings dedicated to control electromagnetic force in each winding. Therefore, the imbalanced electromagnetic force can be restored using this system. The effectiveness of the proposal method is verified by Finite Element Analysis.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130223012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Single-Phase PWM Control of qZSIs for Switching-Loss and Capacitor Reduction Utilizing Accurate DC-Side Current Reference 基于精确直流侧电流基准的qzsi开关损耗和电容减小的单相PWM控制
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9807190
Tomoyuki Mannen
{"title":"Single-Phase PWM Control of qZSIs for Switching-Loss and Capacitor Reduction Utilizing Accurate DC-Side Current Reference","authors":"Tomoyuki Mannen","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9807190","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9807190","url":null,"abstract":"This paper proposes a single-phase PWM control method for qZSIs that utilizes an accurate dc-side current reference, and that can reduces the number of the switching to 1/3. The proposed method regulates the average voltage of the dc-link in the impedance source so as to follow the highest line-to-line voltage of the ac mains. In this case, only one of three legs in qZSI operates under a high-frequency PWM and the other legs operate under the line-frequency switching in the proposed method. This paper also theoretically discusses the inductor current of the impedance source. As a result, this paper reveals that the capacitance of the impedance source strongly affects to the inductor current ripple and that the qZSI should minimize its capacitance in the impedance source to achieve its best performance. The proposed single-phase PWM are verified in experiments. The experimental results exhibit its highest efficiency of 97.6% at 1.1 kW by using a fabricated full-Si-based qZSI. The proposed single-phase PWM can reduce the power loss in the qZSI to less than half compared to a conventional modulation method. It is confirmed the validity of the theoretical analysis of the proposed method.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126708128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Control System of PV Sources for DC Microgrid with Seamless Switching Operation between I-V Droop Control and MPPT Control 一种I-V下垂控制与MPPT控制无缝切换的直流微电网光伏电源控制系统
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9807105
Yasushi Eto, Y. Noge, M. Shoyama
{"title":"A Control System of PV Sources for DC Microgrid with Seamless Switching Operation between I-V Droop Control and MPPT Control","authors":"Yasushi Eto, Y. Noge, M. Shoyama","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9807105","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9807105","url":null,"abstract":"As one of the decentralized control methods for the DC microgrid, DC bus signaling is considered which switch an operation mode of each connected converter based on a bus voltage. In a PV converter, a control method that switches between MPPT control, and $V-P$ droop or $V-I$ droop control based on the bus voltage has been studied. This research proposed a new control method for PV converter which switches between MPPT control and $I-V$ droop control with regulating a PV current. Compared to previous method using $V-I$ droop control, the proposed method can reduce a number of dynamic feedback loops, which will simplify the system design. This paper shows that the droop characteristics of the previous and the proposed methods are almost the same, and discusses how to analyze the DC operating point for system design. In addition, the steady-state and dynamic characteristics of the proposed method are confirmed through numerical calculations and circuit simulations.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123864032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Study on Digital Active Gate Driving of DC-DC Converter for Suppressing Switching Surge Voltage 数字有源栅极驱动DC-DC变换器抑制开关浪涌电压的研究
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9806952
Shuhei Fukunaga, Hajime Takayama, T. Hikihara
{"title":"A Study on Digital Active Gate Driving of DC-DC Converter for Suppressing Switching Surge Voltage","authors":"Shuhei Fukunaga, Hajime Takayama, T. Hikihara","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9806952","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9806952","url":null,"abstract":"High-speed switching of SiC unipolar power semiconductor devices induces an anomalous switching surge voltage in the switching operation of power conversion systems. An active gate driving can control the voltage/current behaviors of the power semiconductor device. It expects to suppress the switching surge voltage. We have focused on a fully digitalized active gate driver. In this paper, the digital active gate driver is applied to a SiC MOSFET in a boost DC-DC converter to improve its switching operation. The experimental results revealed that the driver successfully suppressed the switching surge voltage of SiC MOSFET in the converter.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124184323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A Study of 10MHz Multi-Sampling Deadbeat Control for PMSM Drive System using USPM Controller 基于USPM控制器的永磁同步电机驱动系统10MHz多采样无拍控制研究
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9807200
Daisuke Hiroe, Zhang Xiaohan, Ryosuke Suzuki, K. Nakamura, Kotaro Sato, K. Yoshimoto, T. Yokoyama
{"title":"A Study of 10MHz Multi-Sampling Deadbeat Control for PMSM Drive System using USPM Controller","authors":"Daisuke Hiroe, Zhang Xiaohan, Ryosuke Suzuki, K. Nakamura, Kotaro Sato, K. Yoshimoto, T. Yokoyama","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9807200","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9807200","url":null,"abstract":"Lately, permanent magnet synchronous mo-tors (PMSMs) have been widely used in many fields such as industrial equipment, home appliances, and electric vehicles due to its high efficiency and high power density. From previous studies, it has been confirmed that PMSM motor drive system with deadbeat control has a superior response to the current reference. In this paper, a Universal Smart Power Module (USPM) controller is used to realize a high performance motor drive system. Since this controller can achieve 50 MHz sampling of the state variables, a 10 MHz multi-sampling deadbeat control is proposed that uses fast sampling ability to follow the fluctuation of the load disturbance even between carriers, verifications are carried out through simulations and experiments.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123647442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Pixel Relationships-based Regularizer for Retinal Vessel Image Segmentation 基于像素关系的视网膜血管图像分割正则化算法
2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia) Pub Date : 2022-05-15 DOI: 10.23919/IPEC-Himeji2022-ECCE53331.2022.9806976
L. Hakim, Takio Kurita
{"title":"Pixel Relationships-based Regularizer for Retinal Vessel Image Segmentation","authors":"L. Hakim, Takio Kurita","doi":"10.23919/IPEC-Himeji2022-ECCE53331.2022.9806976","DOIUrl":"https://doi.org/10.23919/IPEC-Himeji2022-ECCE53331.2022.9806976","url":null,"abstract":"The task of image segmentation is to classify each pixel in the image based on the appropriate label. Various deep learning approaches have been proposed for image segmentation that offers high accuracy and deep architecture. However, the deep learning technique uses a pixel-wise loss function for the training process. Using pixel-wise loss neglected the pixel neighbor relationships in the network learning process. The neighboring relationship of the pixels is essential information in the image. Utilizing neighboring pixel information provides an advantage over using only pixel-to-pixel information. This study presents regularizers to give the pixel neighbor relationship information to the learning process. The regularizers are constructed by the graph theory approach and topology approach: By graph theory approach, graph Laplacian is used to utilize the smoothness of segmented images based on output images and ground-truth images. By topology approach, Euler characteristic is used to identify and minimize the number of isolated objects on segmented images. Experiments show that our scheme successfully captures pixel neighbor relations and improves the performance of the convolutional neural network better than the baseline without a regularization term.","PeriodicalId":256507,"journal":{"name":"2022 International Power Electronics Conference (IPEC-Himeji 2022- ECCE Asia)","volume":"15 9-10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120892438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
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