A New Robust Experimentally Validated Phase Locked Loop for Power Electronic Control

摘要

P.L.L is one of the circuits frequently used in control in power electronic, such as in active power filters. Its first role in electronic applications, is to identify the frequency (or the angular position) of a periodical signal, in order to generate another signal synchronised with the last one. However, many power applications need a perfect sine signal phase locked to the utility voltages. As the utility voltages are not always sinusoidal and balanced, a P.L.L is used in order to extract its fundamental component. In this paper, a classical P.L.L with all mathematical development confirmed by simulations will be first studied. Then a new robust solution, which provides very good results under unbalanced and distorted voltages, will be proposed. Simulations, validated by experimentations, will confirm the proposed design. An application case will be studied in order to illustrate the performances of this new P.L.L.