{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:22:01Z","timestamp":1760059321090,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,6,6]],"date-time":"2025-06-06T00:00:00Z","timestamp":1749168000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52305276","2022KJ122","KYQD202339"],"award-info":[{"award-number":["52305276","2022KJ122","KYQD202339"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Tianjin Education Commission Research Program Project","award":["52305276","2022KJ122","KYQD202339"],"award-info":[{"award-number":["52305276","2022KJ122","KYQD202339"]}]},{"name":"Tianjin University of Technology and Education Scientific Research Project","award":["52305276","2022KJ122","KYQD202339"],"award-info":[{"award-number":["52305276","2022KJ122","KYQD202339"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In this paper, the concept of symmetry is utilized to optimize the structural parameters and output characteristics of the generator design\u2014that is, the construction and solution of the equivalent magnetic circuit method for the hybrid excitation generator are symmetrical. To address the issues of high excitation loss and low power density in purely electrically excited generators, as well as the difficulty in adjusting the magnetic field in purely permanent magnet generators, a new topology for a built-in permanent magnet and salient-pole electromagnetic hybrid excitation generator is proposed. Firstly, an equivalent magnetic circuit model of the generator is established. Secondly, expressions are derived to describe the relationships between the dimensions of the salient-pole rotor and the permanent magnets and the generator\u2019s no-load induced electromotive force, cogging torque, and air gap flux density. These expressions are then used to analyze the structural parameters that influence the generator\u2019s performance. Thirdly, optimization targets are selected through sensitivity analysis, with the no-load induced electromotive force, cogging torque, and air gap flux density serving as the optimization objectives. A multi-objective genetic algorithm is employed to optimize these parameters and determine the optimal structural matching parameters for the generator. As a result, the optimized no-load induced electromotive force increased from 18.96 V to 20.14 V, representing a 6.22% improvement; the cogging torque decreased from 177.08 mN\u00b7m to 90.52 mN\u00b7m, a 48.88% reduction; the air gap flux density increased from 0.789 T to 0.829 T, a 5.07% improvement; and the air gap flux density waveform distortion rate decreased from 6.22% to 2.38%, a 39.3% reduction. Finally, a prototype is fabricated and experimentally tested, validating the accuracy of the simulation analysis, the feasibility of the optimization method, and the rationality of the generator design. Therefore, the proposed topology and optimization method can effectively enhance the output performance of the generator, providing a valuable theoretical reference for the design of hybrid excitation generators for vehicles.<\/jats:p>","DOI":"10.3390\/sym17060897","type":"journal-article","created":{"date-parts":[[2025,6,6]],"date-time":"2025-06-06T11:08:31Z","timestamp":1749208111000},"page":"897","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Optimization and Design of Built-In U-Shaped Permanent Magnet and Salient-Pole Electromagnetic Hybrid Excitation Generator for Vehicles"],"prefix":"10.3390","volume":"17","author":[{"given":"Keqi","family":"Chen","sequence":"first","affiliation":[{"name":"School of Automobile and Transportation, Tianjin University of Technology and Education, Tianjin 300222, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5509-0937","authenticated-orcid":false,"given":"Shilun","family":"Ma","sequence":"additional","affiliation":[{"name":"School of Automobile and Transportation, Tianjin University of Technology and Education, Tianjin 300222, China"},{"name":"Tianjin Zhenghan Technology Co., Ltd., Tianjin 300222, China"}]},{"given":"Changwei","family":"Li","sequence":"additional","affiliation":[{"name":"School of Automobile and Transportation, Tianjin University of Technology and Education, Tianjin 300222, China"}]},{"given":"Yongyi","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Automobile and Transportation, Tianjin University of Technology and Education, Tianjin 300222, China"}]},{"given":"Jianwei","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Automotive Engineering, Hebei Vocational University of Technology and Engineering, Xingtai 054000, China"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1186\/s10033-019-0334-x","article-title":"Development and Analysis of the Magnetic Circuit on Double-Radial Permanent Magnet and Salient-Pole Electromagnetic Hybrid Excitation Generator for Vehicles","volume":"32","author":"Zhang","year":"2019","journal-title":"Chin. 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Optim."}],"container-title":["Symmetry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-8994\/17\/6\/897\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:47:54Z","timestamp":1760032074000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-8994\/17\/6\/897"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,6,6]]},"references-count":26,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2025,6]]}},"alternative-id":["sym17060897"],"URL":"https:\/\/doi.org\/10.3390\/sym17060897","relation":{},"ISSN":["2073-8994"],"issn-type":[{"type":"electronic","value":"2073-8994"}],"subject":[],"published":{"date-parts":[[2025,6,6]]}}}