Development of a half-wave rectified variable field flux motor for enhancing the environmental friendliness of small battery-powered electric boats

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H01315
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 21010:Power engineering-related
• Research Institution: Nagasaki University
• Principal Investigator: Abe Takashi 長崎大学, 工学研究科, 教授 (30222649)
• Co-Investigator(Kenkyū-buntansha): 浜崎 真一 長崎大学, 工学研究科, 准教授 (80363472) ; 横井 裕一 長崎大学, 工学研究科, 准教授 (80610469) ; 大道 哲二 長崎大学, 工学研究科, 助教 (50739175) ; 大友 佳嗣 長崎大学, 工学研究科, 助教 (60964442)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 可変界磁モータ / 電池推進船 / 同期モータ / ダイオード整流 / ブラシ無し自己励磁

Outline of Final Research Achievements

The objective of this research is to incorporate a half-wave rectified variable field flux motor into the power source of a small battery-powered electric boat. The practicality of the variable field flux motor was confirmed by a principal investigator. By controlling the field flux under various operating conditions, this motor is expected to reduce fuel costs and CO2 emissions by shifting the maximum efficiency point.
During this period, the research team focused on creating a motor design that would enhance efficiency and minimize torque ripple across both low-speed, low-torque, and high-speed, high-torque drive ranges. To verify the results, a prototype was constructed and validated. A variable field flux control method that can maintain high efficiency depending on boat speed and load was established, and this control method was demonstrated on the prototype. Furthermore, the energy consumption of a small battery-powered electric boat was verified using simulations.

Free Research Field

電力工学関連

Academic Significance and Societal Importance of the Research Achievements

SDGsに係る取り組みとして，モータを利用した電動力応用駆動システムの高性能化がある。養殖場や離島沖の浮体式発電システムへの人と物の往来に必要となる小型船舶には，排ガスを海水中に排出する従来のエンジン船舶に変わり，モータで駆動する環境に配慮した電池推進船の利用が必要となる。本研究は研究代表者が提案し実用性を検証してきた可変界磁モータを小型電池推進船の駆動源に適用することを目的としており，その成果は，再生可能エネルギーの導入の更なる加速，地産地消型のシステムの確立，地域に適したエネルギーの有効利用による特産種の養殖，沿岸環境の保全に寄与することで，持続可能な社会の実現に貢献できる。