Structure and Circuit Engineering Features of Stand- Alone Photovoltaic System with a Battery-Capacitive Energy Storage Device

Abstract

The purpose of this research is to analyze the structure and circuit design of stand-alone photovoltaic system with a battery-capacitive energy storage device to ensure voltage stability under peak voltage and a variable nature of the power generated by a solar panel. There is an original active control scheme for a hybrid drive. The peak power of the solar panel was 100 W. The battery part of the energy storage device was represented by a 12 V gel lead-acid battery with a charging capacity of 11 Ah, and the capacitive part consisted of a battery of supercapacitors with an electrostatic capacity of 80 F, an operating voltage of 15.5 V. A rheostat was used as a load during a stationary discharge of the storage device with a resistance of 12 Om, and the pulsed nature of the discharge was simulated using an automobile air compressor. The analysis of circuit design variants that implement the charging process the capacitive part of the energy storage device from a solar panel directly or with a shunt DC/DC converter is performed. Charging and discharging of the battery part was controlled by the ProStar-15 controller. In both cases, charging buffer modes the battery and capacitive parts of the energy storage device were used. The research results have identified ways to increase the stability of the output voltage under peak voltage and the variable nature of electricity generation conditions while increasing the resource of an expensive battery.

Keywords

• stand-alone photovoltaic system
• solar battery
• storage battery
• supercapacitor
• hybrid energy storage device
• charge and discharge controller