Implementation of Phase Locked Loops using Bit-Stream control techniques

Some utility-connected power electronics applications such as reversible rectifiers and active power filters need accurate measurements of the utility phase angle. A phase locked loop (PLL) is an important component of such systems. This paper describes the development of a three phase PLL for utility angle measurement using a new bit-stream control technique, which has several advantages when used for power electronics applications. The PLL structure is developed from standard design equations, and then modeled in full detail using VHDL descriptions of Bit-Stream components. Comparisons of VHDL simulation results with Matlab / Simulink models of the PLL shows that the Bit-Stream version behaves as expected, demonstrating that the Bit-Stream technique is suitable for the implementation of PLL systems.