DC-AC photonic power converters with liquid crystal optical modulators

Area of Science:

• Photonics
• Power Electronics
• Materials Science

Background:

• Traditional DC-AC power converters rely on power switches, which can generate electromagnetic interference (EMI).
• Switching-induced EMI poses challenges in sensitive electronic applications, necessitating alternative commutation methods.
• Liquid-crystal optical modulators (LCOMs) offer continuous modulation capabilities for optical flux control.

Purpose of the Study:

• To propose and demonstrate a novel power-switch-free (PSF) DC-AC photonic power converter (PPC).
• To leverage LCOMs for optical flux commutation, thereby eliminating power switches and associated EMI.
• To evaluate the power quality, specifically total harmonic distortion (THD), of the proposed PSF-PPC topology.

Main Methods:

• Development of a PSF DC-AC PPC utilizing LCOMs for optical flux commutation.
• Characterization of the prototype converter's output waveform and THD across various frequencies.
• Experimental validation of the LCOM-based optical commutation technique.

Main Results:

• The prototype PSF-PPC successfully demonstrated the feasibility of switch-free commutation.
• Quasi-sinusoidal output waveforms were achieved with low total harmonic distortion (THD).
• THD values ranged from 3.4% to 6.9% between 10-100 Hz, indicating improved power quality.

Conclusions:

• Liquid-crystal optical commutation presents a viable alternative to traditional power switching in DC-AC PPCs.
• The proposed PSF-PPC topology significantly reduces or eliminates switching-induced EMI.
• This technology holds strong potential for enhancing PPC performance in EMI-sensitive applications.