Sliding Mode Direct Power Control of a Grid-Connected DFIG Using an Extended State Observer (Book Title: Emerging Trends in Sliding Mode Control)
Authors :- Ankit Shah and Axaykumar Mehta
Publication :- Studies in Systems, Decision and Control book series (SSDC, volume 318) Springer, 2021
This chapter presents the Sliding Mode (SM)-Direct Power Control (DPC) scheme based on Extended State Observer (ESO) for a grid-connected Doubly-Fed Induction Generator (DFIG) run by a variable-speed wind turbine to regulate stator active and reactive powers. Wind Energy Conversion System (WECS) exhibits a high amount of disturbances such as parameter variations of turbine and generator, unbalanced grid voltage and variation in frequency. These disturbances or nonlinearities pose a serious threat to the performance of a controller. ESO estimates the state variables and lumped disturbances in a system. These estimated state variables which are free from disturbances are fed back for the design of the controller algorithm. This approach attenuates the effect of disturbances on the controller performance. The efficacy of the proposed controller scheme is demonstrated by simulations on a 5 kW DFIG system. The results are compared with the SM-DPC scheme without ESO to corroborate the superior performance of the proposed controller scheme based on ESO.