Fast harmonic analysis for PHIL experiments with decentralized real-time
controllers
Abstract
The paper has been submitted to PSCC 2022 and is currently
awaiting reviews.
This paper proposes and implements, a harmonic analysis algorithm for
microgrid Power Hardware-in-the-loop (PHIL) experiments, when the point
of common coupling (PCC) voltage cannot be directly wired to the local
prosumer controllers due to long distances between them. Using
frequency-shifting and filtering ideas, the voltage measurement is
converted to magnitude and phase information. This is passed over an
asynchronous communication link to another controller, where it is
recovered into a waveform after delay compensation. The method allows
for accurate power calculations and grid synchronization over
distributed prosumer controllers. The proposed method can work at
different execution rates depending on real time (RT) workload and is
shown to be robust against step changes, harmonics and communication
delays. The method is demonstrated with two PHIL experiments at the
CoSES, TU Munich lab in grid connected and island mode.