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DC-link voltage fluctuation, originated from the single-phase power supply, has a significant impact on the railway traction drive system. Instead of employing a large LC filter to suppress the fluctuation, software solutions are of more interests, since they do not add additional components to the system. A state-of-the-art feedforward strategy predicts the dc-link voltage pattern based on its repetitive nature and directly modifies the duty cycle fed to the inverter to eliminate the impact of the fluctuation. Yet this strategy requires a symmetrical and consistent pulse pattern. In this paper, a compensation approach for synchronous space vector modulation with multiple pulse patterns is proposed. It utilizes the prediction of the dc-link voltage pattern and, based on the volt–second balancing principle, modifies the switching instants corresponding to different pulse patterns. Simulation and experimental results show that the proposed method can significantly eliminate the impact of the fluctuation. [ABSTRACT FROM PUBLISHER]