A Small-Sized High-Precision Digital Closed-Loop Modulation Method for Dead-Time Compensation for Flying Capacitor Three-Level Inverters

This article proposes a small-scale high-precision digital closed-loop modulation method for a flying-capacitor three-level inverter to eliminate the influence of dead time. The proposed method only uses a resistive voltage divider to collect the state information, without the need for a current sensor and an analog-to-digital converter, enabling a small footprint. This method does not require complex calculations, can be applied to high switching frequencies, and is independent of the original control system, so it is easy to integrate into a controller or a stand-alone IC. Finally, a 450-W/400-Hz prototype is built to verify the effectiveness of the proposed method.