Sigma-Modified Power Control and Parametric Adaptation in a Grid-Integrated PV for EV Charging Architecture
Debasish Mishra, Bhim Singh, Bijaya Ketan Panigrahi
Abstract
This paper presents a sigma-modified adaptive control algorithm to enhance the charging profile in a multi-objective electric vehicle (EV) charging installation. The presented algorithm takes care of multiple parametric variations and provides an instantaneous control updation to achieve well-regulated charging dynamics in presence of grid non-idealities. With the support of renewable energy and battery energy storage, the present algorithm also ensures an uninterrupted charging profile with controller robustness and stability for bi-directional EV charging. An iterative grid frequency estimator is also adopted to update the reference error dynamics in accordance with each sample unit of supply voltage to guarantee improved power quality operation with non-linear charging dynamics. To further improve the reliability of EV charging installation and fast charging opportunities, a solar photovoltaic (PV) array in conjunction with the storage unit supports the ancillary services through maximum power point operation. Multivariable sliding mode control and rule-based phase-shift adaptation at different stages of power transformation assure faster convergence, stability, and controller robustness for the bi-directional EV charging operation. A 3.3kW PV-integrated off-board charging facility is designed and developed as a laboratory prototype to validate the multi-mode charging architecture with minimal grid dependency.