| Abstract |
This work proposes a simplified online parameter estimation technique for the filter and grid impedances for VSIs connected to the grid via an L-filter and compares the results with the standard estimating methods. The measured L-filter parameters extracted via an LCR meter and the manufacture's datasheet are limited in accuracy since they ignore the switching behavior of the PWM-based VSIs. These methods neglect second-order effects such as the skin effect and hysteresis losses. The proposed parameter estimation technique is straightforward and does not require an additional change in the existing hardware. Further, the estimated filter parameters also include the losses present in the switches and the magnetic cores. Open-loop and Command Tracking (CT) plots of both hardware and simulation are used to validate, analyze, and compare the studied concepts. The proposed online parameter estimation technique is found to be superior compared to the studied parameter estimation techniques. |
