Sistem Pemutus Tegangan pada Stasiun Pengisian Daya Baterai Laptop dengan Tenaga Surya Berbasis Sensor Ina219

Abstract

This research aimed to design and implement an automatic voltage cutoff system and an RFID-based smart lock for a solar-powered laptop charging station. The system was designed to address two main issues: the risk of overcharging the storage battery and the security of devices during public charging. The system consisted of a 100 Watt-peak solar panel, a solar charge controller (SCC), a 12Ah VRLA battery, an inverter, an INA219 sensor to monitor electrical parameters (voltage, current, power), a relay module as an automatic cutoff, and an RC522 RFID module and servo motor for the smart lock security system. An Arduino Nano microcontroller was used as the main controller to process data from the sensors and activate the relay when the voltage exceeded the safe limit of 14.4V. Test results showed that the system successfully prevented overcharging by automatically cutting off the power flow and secured charging access only for users with registered RFID cards, with a 100% success rate. The average voltage, current, and power generated during the three-day testing period were 13.34V, 3.4A, and 45.65W, respectively. The system proved to be efficient, secure, and feasible as a renewable energy-based laptop charging solution for locations with limited electricity access.