Abstract：The four inverters parallel connection based on carrier phase shift (IPC-CPS) is proposed in this paper. In this way, the comparatively low voltage and large current of the linear synchronous motor for drive system are satisfied, when the maglev train at the starting stage. The inverters are connected by inductors. The carrier phase shift technique is adopted, and carrier phase differentiates π/2 from each other. The harmonic components are reduced greatly comparing to the traditional four parallel connection inverters with same carrier phase. This paper makes theoretical harmonic analysis by a new frequency domain mathematical method. The quantitative relationship between fundamental magnitude, harmonics magnitude and modulation factor is given. The simulation shows the feasibility of the proposed control scheme and analysis method.
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2011, Vol. 26 
