Efficiency and utilization benefits of five-phase squirrel cage induction and permanent magnet synchronous machines with third harmonic voltage injection

创新主题：本研究项目的目的是系统比较脉宽调制逆变器供电的三相和五相鼠笼式感应（SCIM）和永磁电机（PMSM）在定子绕组给定温升下的最大效率、转矩/总损耗比和转矩/体积。项目内容：调查是基于一个标准的三相感应电动机（15千瓦，1474 /分钟，400 V）和一个标准的三相逆变器从知名的制造商。对于相同的机械，电气，热和几何约束，五相SCIM和三相和五相永磁同步电动机的解析和数值设计。建立了四台机器，并进行了实验研究，以验证理论结果。前期工作：通过分析和数值计算，为一家汽车供应商设计了几个五相SCIM。针对皮带起动发电机的特殊应用，研究了五相SCIM与PMSM的优缺点。基本研究结果已发表或正在准备发表。项目目标：由于三相与五相SCIM和PMSM在可实现的效率和电机利用率方面的彻底比较仍然缺失，在相同有效质量下的理论和实验比较将突出相位从三相增加到五相以及三次谐波注入的可能益处。拟议的研究项目应回答以下问题：a）在额定运行时：从三相增加到五相时，每总损耗比的扭矩如何变化？五相电机比三相电机运行效率高吗？如果应用三次谐波注入，效率会提高多少？B）在逆变器电流限制下，通过将相位从3增加到5，可以增加最大可实现转矩（过载能力）吗？c）从三相增加到五相对转子拓扑有何影响？应分析SCIM的转子导条数量和偏斜角。应分析永磁同步电机的磁体布置（埋入式、表面式、V形）。d）在弱磁范围内，相位从三个增加到五个，对最大转矩和效率的性能有何影响？e）从三相增加到五相时，噪声、振动和转矩涟漪有何影响？三相或五相电机使用的最终建议以及三次谐波电压注入设计和应用的一般规则应作为项目的最终输出。将制定关于五相SCIM和PMSM益处的一般规则。这些结果将有助于判断增加的系统复杂性是否值得五相变速驱动器的好处。

Subject of innovation: The objective of this research project is the systematic comparison of pulse width modulation inverter-fed three- and five-phase squirrel cage induction (SCIM) and permanent magnet machines (PMSM) concerning maximum efficiency, torque per total loss ratio and torque per volume at a given temperature rise of the stator winding. Content of the project: The investigation is based on a standard three-phase induction motor (15 kW, 1474 /min, 400 V) and a standard three-phase inverter from well-known manufacturers. For the same mechanical, electrical, thermal and geometrical constraints, a five-phase SCIM and a three- and five-phase PMSM are analytically and numerically designed. The four machines are built and an experimental study shall verify the theoretical results. Preliminary work: Analytical and numerical calculations led to the design of several five-phase SCIMs for an automotive supplier. The benefits and drawbacks of five-phase SCIMs versus PMSMs for the special application of a belt-starter-generator were worked on. Basic findings were published or are in preparation for publication. Objective of the project: As a thorough comparison of three- versus five-phase SCIMs and PMSMs concerning achievable efficiency and motor utilization is still missing, a theoretical and experimental comparison at identical active mass will highlight the possible benefit of an increase of phases from three to five and of the third harmonic injection. The following questions shall be answered by the proposed research project: a) At rated operation: How does the torque per total loss ratio change by the increase of phases from three to five? Do five-phase machines operate more efficient than three-phase machines? How much does the efficiency improve if third harmonic injection is applied? b) Can the maximum achievable torque (overload capability) at the inverter current limit be increased by an increase of phases from three to five? c) How is the rotor topology influenced by the increase of phases from three to five? The number of rotor bars and the skewing angle shall be analyzed for the SCIM. The magnet arrangement (buried, surface, V-shape) shall be analyzed for the PMSM. d) How is the performance in terms of maximum torque and efficiency influenced in field weakening range by an increase of phases from three to five? e) How is the acoustic noise, the vibration and the torque ripple influenced by the increase of phases from three to five? A final recommendation for the use of three- or five-phase machines and general rules for design and application of third harmonic voltage injection shall be the final output of the project. General rules on the benefits of five-phase SCIMs and PMSMs will be set up. These results shall help to judge if the increased system complexity is worth the benefits of five-phase variable speed drives.