Electric Trike Battery Charging Hub Station Controller

The Songa Hub Station is a production-grade Electric Trike battery swap station controller engineered to coordinate and monitor multiple charging and battery management nodes within a centralized swap station environment. The system operates as the master controller within the station architecture, communicating with distributed slave devices over an industrial RS-485 bus. Each slave node interfaces with a CAN-based charger and an RS-485-enabled Battery Management System (BMS), enabling centralized supervision of battery charging, battery health, charger operation, and power distribution across the entire swap station.

The hub controller was designed around an ESP32-based embedded architecture integrated with a Quectel EG915N-EU cellular module for secure MQTTs communication with the central cloud platform. Through this connection, the hub receives remote commands, performs remote procedure call (RPC) execution, publishes telemetry from all connected nodes, and supports remote provisioning and diagnostics. The firmware architecture follows an RTOS safe-task model with multiple concurrent FreeRTOS tasks pinned across ESP32 cores for deterministic execution, system isolation, watchdog reliability, and efficient handling of communication-intensive workloads.

From an engineering perspective, the project involved complete end-to-end development including embedded hardware design, RS-485 communication architecture, cellular MQTT integration, RTOS task orchestration, PCB design, hand assembly, production testing, node provisioning logic, and real-world swap station deployment. The system was engineered to support scalable station expansion while maintaining reliable telemetry publishing, robust fault handling, and continuous monitoring of charger and battery operations in electrically noisy field environments.