Soft-Start Method for Boost Converter Under Rapid Irradiance Changes

The modern power system is facing a high penetration of distributed energy resources such as photovoltaic (PV) powered installations. These systems are subject to intermittent operation due to the changing environmental conditions. The systems can face rapid changes in irradiance that lead to the reinitialization of the converter. In this sense, it is necessary to provide safe procedures that enable the operation of the converter under any condition. In this work, a soft-start method is presented for the boost converter that is part of a two-stage PV system configuration. The open circuit voltage of the PV system is used as an indicator of the estimated available power and to detect rapid irradiance changes. Besides, the implementation consists of simple timers and comparisons that can be carried out in available microcontrollers that are used to implement the control routines. Simulation results confirm the operation of the converter under step changes of irradiance for both flexible and maximum power point operation modes.