Open Loop Synchronization Techniques Benchmarking for Distributed Energy Sources Connection

Abstract

Synchronization is a crucial process in the operation of grid-connected distributed energy sources. Synchronization techniques are classified in closed-loop (CLS) and open-loop synchronization (OLS) techniques. Unlike the CLS technique, OLS techniques are recent and less known. This paper discusses a comparative analysis of the three prominent state-of-the-art OLS techniques. Accordingly, a benchmark model is proposed to systematically evaluate the performance of the OLS techniques under grid voltage disturbances such as harmonic distortions, voltage unbalance, DC offset, and low voltage ride through operation. Given the hardware resource utilization, the computational complexity and the execution time are also presented to judge the efficacy of the proposed model. Thus, engineers/or researchers can better understand the choice of hardware resources and the preferred dynamic performance of a synchronization scheme applied to control and protect a grid-tied power converter. Simulation and experimental results are presented and discussed to demonstrate the purpose of the proposed model.

Keywords

• Open-loop synchronization
• benchmark
• delayed-signal cancellation
• reduced-order generalized integrator
• renewable energy sources
• grid side converters