Improved Voltage Regulation of PV System With Current-Sensorless Active Damping Technique

Abstract

Due to changing environmental conditions, mainly irradiance, photovoltaic (PV)-interfaced converters inevitably switch between continuous conduction mode and discontinuous conduction mode. Two modes present significantly different characteristics. Moreover, the dynamics in each mode is also dependent on the operating point. This article focuses on the system dynamics and proposes a new control scheme in the voltage-mode framework that enables the mixed conduction mode operation with consistently fast and null overshoot performance. A single control law is made possible for the entire operating range without complex adaptive mechanisms owning to the PV voltage feedback active damping technique. The controller tuning is designed to meet the desired settling time specified by the MPPT requirement. The advantages are validated with numeral simulations and experimental results in comparison to various available control proposals.