Mitigating Twice the Fundamental Frequency Ripple in Three-Phase to Single-Phase Power Converters through Improved DC Link Voltage Control

Single phase grid connected converters suffer from the well-known pulsation of power at twice the fundamental frequency. This ripple affects the current in the three-phase AC system through the DC link voltage control, leading to inefficiencies and potential reliability concerns. An improved DC link voltage control algorithm, based on the small signal approach, is proposed in this paper, in order to ensure constant input power on the three-phase side despite the pulsating single-phase output power. This algorithm theoretically eliminates the twice ripple effect on 3ϕ quantities, optimising harmonic content and system performance. Simulation results validate the effectiveness of the method, with experimental validation planned for a same scale power conversion system. These results will be detailed in an extended version of this paper. Compared to conventional solutions, this approach significantly improves three-phase side ripple mitigation, increasing the performance and reliability of the power conversion system without the need for additional equipment.