A Novel 2N+1 Carrier-Based Pulse Width Modulation Scheme for Modular Multilevel Converters with Reduced Control Complexity

This paper introduces a less computational intensive pulse width modulation (PWM) scheme to generate a 2N+1 multilevel waveform at the output of a modular multilevel converter (MMC). The proposed approach requires a single triangular carrier to achieve 2N+1 modulation in an MMC with a large number of submodules (SMs). Hence, this scheme solves the computational and practical implementation issues associated with the traditional phase-shifted carrier PWM (PSC-PWM) schemes in the digital control platforms. The performance of the proposed modulation scheme is demonstrated through MATLAB/SIMULINK simulations and experimental results. The results show that the proposed scheme generates a multilevel waveform at load terminals and has an identical performance in comparison to the conventional PSC-PWM scheme with reduced control complexity.