Harmonic reduction by designing a three phase to eleven phase transformer fed eleven-phase induction motor

Three phase supply is available in the generating station or grid, were as eleven phase supply is required for many industrial applications such as, aerospace, railway and automobile applications. There aredifferent methods in which we can convert 3 to 11 phase using 18-Pulse Converter, Carrier Based PWM Technique, multilevel converter and Multiphase Transformer. The above said methods which are more complicated to design for higher ratings or a pure sine wave will not be obtained or harmonics will bemore . For Multiphase power transmission system multiphase transformers are needed. In the multiphasepower transmission and multiphase rectifier systems, the number of phase can be designed and developed in multiples of three. Therefore, the variable speed multiphase drive system considered in the literature are mostly of five, seven, nine, eleven, twelve, and fifteen phase . So, there is a need to design anddevelop special transformer which converts from 3 to 11 phase for different arrangement of input andoutput. Thus, with the proposed technique, a pure eleven-phase sine-wave of fixed voltage/current and frequency is obtained, which can be used for RL load and motor testing purposes.

Keywords:

Multi winding transformer , Multiphase transmission , Three-to-eleven phase