Low-cost digital realization of phase synchronization for grid tied micro inverter

Grid-tied micro-inverters are reported to ensure higher energy harvest, but the requirement of large unit quantities raises concerns about cost. Low-cost processors as the control platform are therefore desirable but these are hamstrung with low numerical precision, which causes serious errors while numerically executing the control algorithms. In this paper, the crucial aspect of automatic phase synchronization is investigated and errors with conventional approaches noted. Also, a computationally light algorithm, based on Linear Interpolation, is proposed which successfully overcomes these errors. Analytical and experimental results are provided to comprehensively prove its efficacy.