DC-AC photonic power converters with liquid crystal optical modulators

In this Letter, we propose a power-switch-free (PSF) DC-AC photonic power converter (PPC) that utilizes liquid-crystal optical modulators (LCOMs) to commutate optical flux, thereby eliminating the need for power switches and avoiding switching-induced electromagnetic interference (EMI). Leveraging the LCOM's capability for continuous optical-flux modulation, the proposed topology maintains a quasi-sinusoidal output with a low total harmonic distortion (THD), thereby improving power quality. A prototype converter is developed in this work, which demonstrates the feasibility of the PSF DC-AC PPC, with THD values ranging from 3.4% to 6.9% across the frequency range of 10-100 Hz. Experimental results indicate that liquid-crystal-based optical commutation offers strong potential for enhancing PPC performance in EMI-sensitive applications.