A phase-modulated high-frequency isolated dual LCL DC/AC converter

A phase-modulated high-frequency isolated DC/AC converter is proposed for a PMSG-based grid-connected wind generation application. The converter includes two full-bridge HF LCL-type resonant inverters working at fixed duty cycle. The power control is realized by means of the phase shift between the two bridges. With the LCL-type resonant tank, zero-voltage-switching is achieved for all switches for the whole power range. With the phase shift modulated sinusoidally, a 120 Hz rectified output current is obtained, which is unfolded and fed to the single-phase utility line. The analysis is verified with computer simulation results. Experimental data based on a 500 W prototype circuit is included for validation purpose.