Carrier-Based MPC for Interleaved 2L-VSIs with Reduced Low-order Zero-Sequence Circulating Current

In this paper, a carrier-based model predictive control (CB-MPC) algorithm is proposed to regulate power sharing of paralleled two-level voltage-sourced inverters (2L-VSIs). Carriers are adopted in the proposed controller to enable interleaving. The proposed controller can be implemented in either distributed or centralized manner, depending on the application circumstances. The distributed CB-MPC is more suitable for large modular parallel inverter systems where communication lines are prohibited. On the other hand, the low-order zero-sequence circulating current (ZSCC) can be fully eliminated with proposed centralized CB-MPC, when communications become available among a small number of paralleled inverter modules. With either scheme, multiple goals can be achieved including fast dynamic response, carrier interleaving, fixed switching frequency, ZSCC elimination, and reduced computational burden; which makes the proposed method a practical MPC solution for various industrial applications. Effectiveness of the proposed CB-MPC has been verified by simulation and experimental results.