Pub Date : 2024-06-01DOI: 10.30941/CESTEMS.2024.10051
As with the continuous advancement of the low-carbon energy development, the wind power generation experiences fast growth with 441.3 GW installed capacity by Dec. 2023. The high penetration of renewable energy, together with high penetration of power electronic equipment (namely, “double high”), has been altering the steady-state and transient characteristics of wind power generation in a profound way, resulting in the different risk of instability. These stability issues will seriously affect the consumption of renewable energy and threaten the safe supply of electricity. Along with rapid deployment of wind power generation, together with the solar photovoltaic generation, it is expected to be over 1200 GW by 2030.
{"title":"Message from Editors","authors":"","doi":"10.30941/CESTEMS.2024.10051","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.10051","url":null,"abstract":"As with the continuous advancement of the low-carbon energy development, the wind power generation experiences fast growth with 441.3 GW installed capacity by Dec. 2023. The high penetration of renewable energy, together with high penetration of power electronic equipment (namely, “double high”), has been altering the steady-state and transient characteristics of wind power generation in a profound way, resulting in the different risk of instability. These stability issues will seriously affect the consumption of renewable energy and threaten the safe supply of electricity. Along with rapid deployment of wind power generation, together with the solar photovoltaic generation, it is expected to be over 1200 GW by 2030.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 2","pages":"113-114"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10579826","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495327","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}
Virtual synchronous generators (VSGs) are widely introduced to the renewable power generation, the variable-speed pumped storage units, and so on, as a promising grid-forming solution. It is noted that VSGs can provide virtual inertia for frequency support, but the larger inertia would worsen the synchronization stability, referring to keeping synchronization with the grid during voltage dips. Thus, this paper presents a transient damping method of VSGs for enhancing the synchronization stability during voltage dips. It is revealed that the loss of synchronization (LOS) of VSGs always accompanies with the positive frequency deviation and the damping is the key factor to remove LOS when the equilibrium point exists. In order to enhance synchronization stability during voltage dips, the transient damping is proposed, which is generated by the frequency deviation in active power loop. Additionally, the proposed method can realize seamless switching between normal state and grid fault. Moreover, detailed control design for transient damping gain is given to ensure the synchronization stability under different inertia requirements during voltage dips. Finally, the experimental results are presented to validate the analysis and the effectiveness of the improved transient damping method.
虚拟同步发电机(VSG)作为一种有前途的电网形成解决方案,被广泛引入可再生能源发电、变速抽水蓄能机组等领域。人们注意到,VSGs 可以为频率支持提供虚拟惯性,但较大的惯性会恶化同步稳定性,即在电压骤降时与电网保持同步。因此,本文提出了一种 VSG 瞬态阻尼方法,以增强电压暂降期间的同步稳定性。研究表明,VSG 的同步损失(LOS)总是伴随着正频率偏差,而当平衡点存在时,阻尼是消除 LOS 的关键因素。为了增强电压骤降期间的同步稳定性,提出了由有功功率环路频率偏差产生的瞬态阻尼。此外,所提出的方法还能实现正常状态和电网故障之间的无缝切换。此外,还给出了暂态阻尼增益的详细控制设计,以确保电压暂降期间不同惯性要求下的同步稳定性。最后,介绍了实验结果,以验证分析结果和改进的暂态阻尼方法的有效性。
{"title":"Transient Damping of Virtual Synchronous Generator for Enhancing Synchronization Stability During Voltage Dips","authors":"Shitao Sun;Yu Lei;Guowen Hao;Yi Lu;Jindong Liu;Zhaoxin Song;Jie Zhang","doi":"10.30941/CESTEMS.2024.00021","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00021","url":null,"abstract":"Virtual synchronous generators (VSGs) are widely introduced to the renewable power generation, the variable-speed pumped storage units, and so on, as a promising grid-forming solution. It is noted that VSGs can provide virtual inertia for frequency support, but the larger inertia would worsen the synchronization stability, referring to keeping synchronization with the grid during voltage dips. Thus, this paper presents a transient damping method of VSGs for enhancing the synchronization stability during voltage dips. It is revealed that the loss of synchronization (LOS) of VSGs always accompanies with the positive frequency deviation and the damping is the key factor to remove LOS when the equilibrium point exists. In order to enhance synchronization stability during voltage dips, the transient damping is proposed, which is generated by the frequency deviation in active power loop. Additionally, the proposed method can realize seamless switching between normal state and grid fault. Moreover, detailed control design for transient damping gain is given to ensure the synchronization stability under different inertia requirements during voltage dips. Finally, the experimental results are presented to validate the analysis and the effectiveness of the improved transient damping method.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 2","pages":"143-151"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10579824","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495287","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}
Pub Date : 2024-06-01DOI: 10.30941/CESTEMS.2024.00024
Gaojia Zhu;Yunhao Li;Longnv Li
With the continuous improvement of permanent magnet (PM) wind generators' capacity and power density, the design of reasonable and efficient cooling structures has become a focus. This paper proposes a fully enclosed self-circulating hydrogen cooling structure for a originally forced-air-cooled direct-drive PM wind generator. The proposed hydrogen cooling system uses the rotor panel supports that hold the rotor core as the radial blades, and the hydrogen flow is driven by the rotating plates to flow through the axial and radial vents to realize the efficient cooling of the generator. According to the structural parameters of the cooling system, the Taguchi method is used to decouple the structural variables. The influence of the size of each cooling structure on the heat dissipation characteristic is analyzed, and the appropriate cooling structure scheme is determined.
{"title":"Design Optimization of a Self-Circulated Hydrogen Cooling System for a PM Wind Generator Based on Taguchi Method","authors":"Gaojia Zhu;Yunhao Li;Longnv Li","doi":"10.30941/CESTEMS.2024.00024","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00024","url":null,"abstract":"With the continuous improvement of permanent magnet (PM) wind generators' capacity and power density, the design of reasonable and efficient cooling structures has become a focus. This paper proposes a fully enclosed self-circulating hydrogen cooling structure for a originally forced-air-cooled direct-drive PM wind generator. The proposed hydrogen cooling system uses the rotor panel supports that hold the rotor core as the radial blades, and the hydrogen flow is driven by the rotating plates to flow through the axial and radial vents to realize the efficient cooling of the generator. According to the structural parameters of the cooling system, the Taguchi method is used to decouple the structural variables. The influence of the size of each cooling structure on the heat dissipation characteristic is analyzed, and the appropriate cooling structure scheme is determined.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 2","pages":"170-176"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10579827","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495325","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}
Pub Date : 2024-06-01DOI: 10.30941/CESTEMS.2024.00022
Lu Sun;Haoyu Kang;Jin Wang;Zequan Li;Jianjun Liu;Yiming Ma;Libing Zhou
As the core component of energy conversion for large wind turbines, the output performance of doubly-fed induction generators (DFIGs) plays a decisive role in the power quality of wind turbines. To realize the fast and accurate design optimization of DFIGs, this paper proposes a novel hybrid-driven surrogate-assisted optimization method. It firstly establishes an accurate subdomain model of DFIGs to analytically predict performance indexes. Furthermore, taking the inexpensive analytical dataset produced by the subdomain model as the source domain and the expensive finite element analysis dataset as the target domain, a high-precision surrogate model is trained in a transfer learning way and used for the subsequent multi-objective optimization process. Based on this model, taking the total harmonic distortion of electromotive force, cogging torque, and iron loss as objectives, and the slot and inner/outer diameters as parameters for optimizing the topology, achieve a rapid and accurate electromagnetic design for DFIGs. Finally, experiments are carried out on a 3MW DFIG to validate the effectiveness of the proposed method.
{"title":"Analytical Model and Topology Optimization of Doubly-Fed Induction Generator","authors":"Lu Sun;Haoyu Kang;Jin Wang;Zequan Li;Jianjun Liu;Yiming Ma;Libing Zhou","doi":"10.30941/CESTEMS.2024.00022","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00022","url":null,"abstract":"As the core component of energy conversion for large wind turbines, the output performance of doubly-fed induction generators (DFIGs) plays a decisive role in the power quality of wind turbines. To realize the fast and accurate design optimization of DFIGs, this paper proposes a novel hybrid-driven surrogate-assisted optimization method. It firstly establishes an accurate subdomain model of DFIGs to analytically predict performance indexes. Furthermore, taking the inexpensive analytical dataset produced by the subdomain model as the source domain and the expensive finite element analysis dataset as the target domain, a high-precision surrogate model is trained in a transfer learning way and used for the subsequent multi-objective optimization process. Based on this model, taking the total harmonic distortion of electromotive force, cogging torque, and iron loss as objectives, and the slot and inner/outer diameters as parameters for optimizing the topology, achieve a rapid and accurate electromagnetic design for DFIGs. Finally, experiments are carried out on a 3MW DFIG to validate the effectiveness of the proposed method.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 2","pages":"162-169"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10579828","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141494912","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}
Pub Date : 2024-06-01DOI: 10.30941/CESTEMS.2024.00025
Bo Pang;Qi Si;Pan Jiang;Kai Liao;Xiaojuan Zhu;Jianwei Yang;Zhengyou He
High-frequency oscillation (HFO) of grid-connected wind power generation systems (WPGS) is one of the most critical issues in recent years that threaten the safe access of WPGS to the grid. Ensuring the WPGS can damp HFO is becoming more and more vital for the development of wind power. The HFO phenomenon of wind turbines under different scenarios usually has different mechanisms. Hence, engineers need to acquire the working mechanisms of the different HFO damping technologies and select the appropriate one to ensure the effective implementation of oscillation damping in practical engineering. This paper introduces the general assumptions of WPGS when analyzing HFO, systematically summarizes the reasons for the occurrence of HFO in different scenarios, deeply analyses the key points and difficulties of HFO damping under different scenarios, and then compares the technical performances of various types of HFO suppression methods to provide adequate references for engineers in the application of technology. Finally, this paper discusses possible future research difficulties in the problem of HFO, as well as the possible future trends in the demand for HFO damping.
{"title":"Review of the Analysis and Suppression for High-Frequency Oscillations of the Grid-Connected Wind Power Generation System","authors":"Bo Pang;Qi Si;Pan Jiang;Kai Liao;Xiaojuan Zhu;Jianwei Yang;Zhengyou He","doi":"10.30941/CESTEMS.2024.00025","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00025","url":null,"abstract":"High-frequency oscillation (HFO) of grid-connected wind power generation systems (WPGS) is one of the most critical issues in recent years that threaten the safe access of WPGS to the grid. Ensuring the WPGS can damp HFO is becoming more and more vital for the development of wind power. The HFO phenomenon of wind turbines under different scenarios usually has different mechanisms. Hence, engineers need to acquire the working mechanisms of the different HFO damping technologies and select the appropriate one to ensure the effective implementation of oscillation damping in practical engineering. This paper introduces the general assumptions of WPGS when analyzing HFO, systematically summarizes the reasons for the occurrence of HFO in different scenarios, deeply analyses the key points and difficulties of HFO damping under different scenarios, and then compares the technical performances of various types of HFO suppression methods to provide adequate references for engineers in the application of technology. Finally, this paper discusses possible future research difficulties in the problem of HFO, as well as the possible future trends in the demand for HFO damping.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 2","pages":"127-142"},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10579809","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495302","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}
Pub Date : 2024-03-31DOI: 10.30941/CESTEMS.2024.00017
Yutong Zhu;Yaohua Li
Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results.
{"title":"A Loss-Model-Based Efficiency Optimization Control Method for Induction Traction System of High-Speed Train Under Emergency Self-Propelled Mode","authors":"Yutong Zhu;Yaohua Li","doi":"10.30941/CESTEMS.2024.00017","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00017","url":null,"abstract":"Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results.","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 2","pages":"227-239"},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10545326","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141495326","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}
Pub Date : 2024-03-30DOI: 10.30941/CESTEMS.2024.00801
{"title":"Comments and Corrections","authors":"","doi":"10.30941/CESTEMS.2024.00801","DOIUrl":"https://doi.org/10.30941/CESTEMS.2024.00801","url":null,"abstract":"","PeriodicalId":100229,"journal":{"name":"CES Transactions on Electrical Machines and Systems","volume":"8 2","pages":"240-241"},"PeriodicalIF":0.0,"publicationDate":"2024-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10541945","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141494920","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}