Chinese Journal of Electrical Engineering最新文献_第3页

Accurate 3D Thermal Network Development for Direct-Drive Outer-Rotor Hybrid-PM Flux-Switching Generator 直驱外转子混合动力-PM 通量切换发电机的精确 3D 热网开发

Chinese Journal of Electrical Engineering Pub Date : 2024-06-01 DOI: 10.23919/CJEE.2024.000059

Ali Zarghani;Mohammad Farahzadi;Aghil Ghaheri;Karim Abbaszadeh

{"title":"Accurate 3D Thermal Network Development for Direct-Drive Outer-Rotor Hybrid-PM Flux-Switching Generator","authors":"Ali Zarghani;Mohammad Farahzadi;Aghil Ghaheri;Karim Abbaszadeh","doi":"10.23919/CJEE.2024.000059","DOIUrl":"https://doi.org/10.23919/CJEE.2024.000059","url":null,"abstract":"Heat and thermal problems are major obstacles to achieving high power density in compact permanent magnet (PM) topologies. Consequently, a comprehensive, accurate, and rapid temperature rise estimation method is required for novel electric machines to ensure safe and reliable operations. A unique three-dimensional (3D) lumped parameter thermal network (LPTN) is presented for accurate thermal modeling of a newly developed outer-rotor hybrid-PM flux switching generator (OR-HPMFSG) for direct-drive applications. First, the losses of the OR-HPMFSG are calculated using 3D finite element analysis (FEA). Subsequently, all machine components considering the thermal contact resistance, anisotropic thermal conductivity of materials, and various heat flow paths are comprehensively modeled based on the thermal resistances. In the proposed 3-D LPTN, internal nodes are considered to predict the average temperature as well as the hot spots of all active and passive components. Experimental measurements are performed on a prototype OR-HPMFSG to validate the efficiency of the 3-D LPTN. A comparison of the results at various operating points between the developed 3-D LPTN, experimental test, and FEA indicates that the 3-D LPTN quickly approximates the hotspot and mean temperature of all components under both transient and steady states with high accuracy.","PeriodicalId":36428,"journal":{"name":"Chinese Journal of Electrical Engineering","volume":"10 2","pages":"80-92"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10586892","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141543840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Inherently Sinusoidal Single-Phase Voltage Source Inverter Based on Modified Cuk Cell 基于改进型 Cuk 电池的固有正弦单相电压源逆变器

Chinese Journal of Electrical Engineering Pub Date : 2024-03-01 DOI: 10.23919/CJEE.2024.000051

Misbahul Munir;Wisyahyadi;Arwindra Rizqiawan;Jihad Furqani

{"title":"Inherently Sinusoidal Single-Phase Voltage Source Inverter Based on Modified Cuk Cell","authors":"Misbahul Munir;Wisyahyadi;Arwindra Rizqiawan;Jihad Furqani","doi":"10.23919/CJEE.2024.000051","DOIUrl":"https://doi.org/10.23919/CJEE.2024.000051","url":null,"abstract":"Renewable energy has become important for electricity generation because of the high air pollution associated with conventional fossil-based energy systems. Conventional fossil-based power plants are gradually transitioning by incorporating renewable energy sources, such as photovoltaic (PV) cells. In a PV system, an inverter converts DC power from solar panels to AC power required to serve common electrical loads. A conventional H-bridge inverter topology has several disadvantages, such as the voltage being not sinusoidal, switching the DC voltage and high common-mode voltage. The common-mode voltage can cause a large leaked capacitive current, which can result in undesirable operation in solar power applications. A common solution to this problem is the addition of a large filter to the input or output of an inverter. An inherent sinusoidal voltage source inverter based on a modified Cuk converter as its basic cell, which simultaneously generates a sinusoidal output voltage and a lower common-mode voltage, is proposed. The proposed topology does not require additional input or output filters. Analytical expressions are derived to confirm the operation of the proposed topology. Simulation results confirm the mathematical analysis. A laboratory-scale experiment is performed to verify the proposed inverter.","PeriodicalId":36428,"journal":{"name":"Chinese Journal of Electrical Engineering","volume":"10 1","pages":"114-123"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10490168","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140345495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erosion Characteristics of Oil-Immersed On-Load Tap Changer Contacts Under Varying Contact Speeds and Pressures 不同接触速度和压力下油浸式有载分接开关触头的腐蚀特性

Chinese Journal of Electrical Engineering Pub Date : 2024-03-01 DOI: 10.23919/CJEE.2023.000044

Zongying Li;Shuaibing Li;Yongqiang Kang;Zheng Li;Hongwei Li

{"title":"Erosion Characteristics of Oil-Immersed On-Load Tap Changer Contacts Under Varying Contact Speeds and Pressures","authors":"Zongying Li;Shuaibing Li;Yongqiang Kang;Zheng Li;Hongwei Li","doi":"10.23919/CJEE.2023.000044","DOIUrl":"https://doi.org/10.23919/CJEE.2023.000044","url":null,"abstract":"With the growing demand for precise voltage adjustment and reactive regulation, the frequent operation of on-load tap changers (OLTCs) in oil-immersed systems has led to increased erosion of switch contacts by arcs during the switching process. This erosion causes significant wear on the contacts, thereby reducing their lifespan. Therefore, the present study aims to investigate the behavior and mechanism of arc erosion on contact surfaces in oil-immersed OLTCs. To achieve this, a self-designed friction and wear test device for OLTC contacts was utilized to conduct experiments at various sliding speeds and contact pressures. Additionally, finite element analysis was employed to validate the experimental results regarding the influence of sliding speed on arc energy. The surface morphology of the contacts was observed using an optical microscope. The findings revealed that as the sliding speed increased, the arc energy, arc initiation rate, and contact resistance initially exhibited an upward trend, then decreased, and eventually increased again. The minimum values were observed at a sliding speed of 90 mm/s. Moreover, the arc energy, arc initiation rate, and contact resistance decreased gradually as the contact pressure increased. After reaching a contact pressure of 1.5 N, the variation in the arc energy stabilized. At lower contact pressures, arc erosion dominated the wear on the contact surface. However, at higher contact pressures, the wear transitioned from predominantly arc erosion to a combination of mechanical wear and arc erosion. In summary, experimental and analytical investigations provided insights into the effects of sliding speed and contact pressure on the behavior of arc erosion, contact resistance, and surface damage of OLTC contacts in oil-immersed systems.","PeriodicalId":36428,"journal":{"name":"Chinese Journal of Electrical Engineering","volume":"10 1","pages":"21-34"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10490172","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140345460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Editorial for the Special Issue on Emerging Technology and Advanced Application of Nondestructive Detection for Power Equipment 为 "电力设备无损检测的新兴技术和先进应用 "特刊撰写的编辑文章

Chinese Journal of Electrical Engineering Pub Date : 2024-03-01 DOI: 10.23919/CJEE.2024.000055

引用次数: 0

FEA-based Geometrical Modification of Switched Reluctance Motor for Radial Force Reduction 基于有限元分析的开关磁阻电机几何改型可降低径向力

Chinese Journal of Electrical Engineering Pub Date : 2024-03-01 DOI: 10.23919/CJEE.2024.000049

Rani S;Jayapragash R

{"title":"FEA-based Geometrical Modification of Switched Reluctance Motor for Radial Force Reduction","authors":"Rani S;Jayapragash R","doi":"10.23919/CJEE.2024.000049","DOIUrl":"https://doi.org/10.23919/CJEE.2024.000049","url":null,"abstract":"Switched reluctance motors (SRMs) are becoming increasingly popular in the automotive sector owing to their robust design. Moreover, SRMs are preferred particularly for EV applications owing to their fault tolerance, magnet-free structure, and high power/torque density. The main concerns of SRM compared to other machines include torque ripple and vibration. The primary cause of vibration is the radial force created by the SRM. A geometry-based modification of the SRM to reduce the radial force without significantly changing the average torque produced is proposed. The primary goal is to design a 4-phase, 8/6 SRM with a lower radial force. Two possible geometrical alterations are proposed: one with square windows and the other with circular holes on the rotor core. The windows are sized and positioned to avoid flux saturation. General criteria are developed for the optimal window size and placement. Finite element analysis (FEA) modelling of the SRM is used to validate its performance. The FEA results are compared with the performance parameters obtained using the analytical method. Utilizes the multiphysics design tool ANSYS to obtain the natural frequencies and associated deformations through modal analysis. Compared to the conventional geometry, the radial force is significantly reduced by providing windows.","PeriodicalId":36428,"journal":{"name":"Chinese Journal of Electrical Engineering","volume":"10 1","pages":"124-135"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10490166","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140345480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulation of Ultrasonic Propagation in Transformers within Thermal Fields and Intelligent Methodology for Hot-Spot Temperature Recognition 热场中变压器内超声波传播模拟及热点温度识别智能方法

Chinese Journal of Electrical Engineering Pub Date : 2024-03-01 DOI: 10.23919/CJEE.2024.000052

Dongxin He;Dechao Yang;Xinhua Guo;Jiefeng Liu;Haoxin Guo;Qingquan Li;Gilbert Teyssedre

{"title":"Simulation of Ultrasonic Propagation in Transformers within Thermal Fields and Intelligent Methodology for Hot-Spot Temperature Recognition","authors":"Dongxin He;Dechao Yang;Xinhua Guo;Jiefeng Liu;Haoxin Guo;Qingquan Li;Gilbert Teyssedre","doi":"10.23919/CJEE.2024.000052","DOIUrl":"https://doi.org/10.23919/CJEE.2024.000052","url":null,"abstract":"Hot-spot temperature of transformer windings is a crucial indicator of internal defects. However, current methods for measuring the hot-spot temperature of transformers do not apply to those already in operation and suffer from data lag. This study introduces a novel inversion method that combines ultrasonic sensing technology, multiphysics simulation, and the K-nearest neighbors algorithm. Leveraging the penetrative ability and temperature sensitivity of ultrasonic sensing, a detailed physical field simulation model was established. This study extensively investigates the characteristics of ultrasonic wave signals inside transformers. The investigation includes different temperature fields, ranging from 40 °C to 110 °C at 10 °C intervals, and various ultrasonic wave emitter conditions. By extracting the key features of the acoustic signals, such as the peak time, propagation time, and peak amplitude, an accurate inversion of the winding hot-spot temperature is successfully achieved. The results demonstrate that this method achieves a high accuracy rate (98.57%) in inverting the internal winding hot-spot temperatures of transformers, offering an efficient and reliable new approach for measuring winding hot-spot temperatures.","PeriodicalId":36428,"journal":{"name":"Chinese Journal of Electrical Engineering","volume":"10 1","pages":"35-47"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10490167","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140345522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Advanced Electrical Motors and Control Strategies for High-quality Servo Systems - A Comprehensive Review 用于高质量伺服系统的先进电机和控制策略 - 全面回顾

Chinese Journal of Electrical Engineering Pub Date : 2024-03-01 DOI: 10.23919/CJEE.2023.000048

Ming Cheng;Jiawei Zhou;Wei Qian;Bo Wang;Chenchen Zhao;Peng Han

引用次数: 0

Characterization of Electrical Tree Degradation of Epoxy Resin under Thermal and Temperature Stresses by Photoelastic Effect 利用光弹性效应表征环氧树脂在热应力和温度应力下的电树降解特性

Chinese Journal of Electrical Engineering Pub Date : 2024-03-01 DOI: 10.23919/CJEE.2023.000047

Hein Htet Aung;Yuhuai Wang;Jin Li;Ying Zhang;Tatsuo Takada

{"title":"Characterization of Electrical Tree Degradation of Epoxy Resin under Thermal and Temperature Stresses by Photoelastic Effect","authors":"Hein Htet Aung;Yuhuai Wang;Jin Li;Ying Zhang;Tatsuo Takada","doi":"10.23919/CJEE.2023.000047","DOIUrl":"https://doi.org/10.23919/CJEE.2023.000047","url":null,"abstract":"Epoxy resin is widely used in the support, insulation, and packaging components of electrical equipment owing to their excellent insulation, thermal, and mechanical properties. However, epoxy-resin insulation often suffers from thermal and mechanical stresses under extreme environmental conditions and a compact design, which can induce electrical tree degradation and insulation failure in electrical equipment. In this study, the photoelastic method is employed to investigate the thermal-mechanical coupling stress dependence of the electrical treeing behavior of epoxy resin. Typical electrical tree growth morphology and stress distribution were observed using the photoelastic method. The correlation between the tree length and overall accumulated damage with an increase in mechanical stress is determined. The results show that compressive stress retards the growth of electrical trees along the electric field, while tensile stress has accelerating effects. This proves that the presence of thermal stress can induce more severe accumulated damage.","PeriodicalId":36428,"journal":{"name":"Chinese Journal of Electrical Engineering","volume":"10 1","pages":"12-20"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10490171","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140345498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aging Mechanism and Life Estimation of Photovoltaic Inverter DC-link Capacitors in Alternating Humid and Thermal Environment 湿热交替环境下光伏逆变器直流链路电容器的老化机理与寿命估算

Chinese Journal of Electrical Engineering Pub Date : 2024-03-01 DOI: 10.23919/CJEE.2024.000054

Quanyi Gao;Shuaibing Li;Yi Cui;Yongqiang Kang;Haiying Dong

{"title":"Aging Mechanism and Life Estimation of Photovoltaic Inverter DC-link Capacitors in Alternating Humid and Thermal Environment","authors":"Quanyi Gao;Shuaibing Li;Yi Cui;Yongqiang Kang;Haiying Dong","doi":"10.23919/CJEE.2024.000054","DOIUrl":"https://doi.org/10.23919/CJEE.2024.000054","url":null,"abstract":"DC-link capacitors play a vital role in managing ripple voltage and current in converters and various devices. This study focuses on exploring the aging characteristics of DC-link capacitors in alternating humid and thermal environments aligned with the operational conditions in photovoltaic and wind power applications. Adhering to relevant power equipment standards, we designed a 24-h alternating humid and thermal aging environment tailored to the requirements of DC-link capacitors. An aging test platform is established, and 20 widely used metallized polypropylene film capacitors are selected for evaluation. Parameters such as the capacitance, equivalent series resistance (ESR), and phase angle are assessed during aging, as well as the onset time and extent of aging at various intervals. This study focuses on the aging mechanisms, analyzing electrode corrosion, the self-healing process, and dielectric aging. Fitting the aging characteristics enabled us to calculate the lifespan of the capacitor and predict it under different degrees of capacitance decay. The results show that under alternating humid and thermal conditions, capacitance attenuation and ESR increase exhibit exponential nonlinearity, influenced by factors such as the oxidation and self-healing of capacitive metal electrodes, dielectric main-chain fracture, and crystal transformation. This study underscores the pivotal role of encapsulation in determining the aging decay time.","PeriodicalId":36428,"journal":{"name":"Chinese Journal of Electrical Engineering","volume":"10 1","pages":"48-62"},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10490169","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140345502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Review of Isolated Bidirectional DC-DC Converters for Data Centers 数据中心隔离式双向 DC-DC 转换器综述

Chinese Journal of Electrical Engineering Pub Date : 2023-12-06 DOI: 10.23919/CJEE.2023.000034

Shuohang Chen;Guidong Zhang;Samson S. Yu;Yi Mei;Yun Zhang

引用次数: 0