Experimental Analysis of Wireless EV Charging Efficiency in an IoT-Based Smart Parking System with Automated Gate Control and Real-Time Monitoring

This paper has presented, validated, and benchmarked an IoT-integrated Smart Parking platform that co-locates contactless EV charging, live battery telemetry, servo-gated access control, and OTP-secured exit authorisation within a single embedded system. The architecture bridges WPT hardware with cloud analytics to deliver an operationally transparent and cryptographically protected EV parking service. Contact-proximity measurements returned a peak charging efficiency of 92%, and the 80% efficiency floor was maintained for all gap settings up to 2 cm. Receiver terminal voltage, load current, and delivered power each declined monotonically with gap distance, driven by the progressive erosion of magnetic coupling and mutual inductance between the coil pair. The findings establish a clear operational envelope: coaxial coil alignment with a maximum separation of 2 cm is necessary and sufficient to deliver commercially viable wireless charging performance for the prototype coil geometry. Beyond the core energy-delivery function, the convergence of ThingSpeak telemetry, INA219-based battery assessment, servo gate actuation, and dynamic OTP validation elevates the system from a simple charger to a complete smart-parking management node. The architecture is readily extensible: higher-power transmitter coils, AI-driven stall allocation, a dedicated mobile-application interface, and in-motion dynamic charging for continuously moving vehicles represent natural avenues for future development.

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