This study presents a LoRa-Modbus heterogeneous integrated CP line PWM intelligent control center based on STM32F103C8T6 for new energy vehicle charging piles. The system regulates CP line PWM signals and integrates LoRa-Modbus communication. A “programmable voltage division and buffer isolation” architecture enables accurate detection of multi-state signals (12V/9V/6V). High-frequency ADC sampling (10 kHz) with threshold statistics achieves ≤1% duty cycle error. A novel “LoRa physical layer + Modbus application layer” scheme, using the SX1268 chip, supports long-distance transmission and protocol mapping between Modbus registers (0x003C–0x0276) and PWM duty cycles (10%–89.2%), corresponding to 6.0–63.0 A current with 0.1 A resolution. Experiments verify duty cycle tracking error ≤1% without LoRa signals, offering a cost-effective, robust solution for charging pile upgrades.
 

New Energy Vehicle Charging Piles; LoRa-Modbus Heterogeneous Communication; Control Pilot PWM Signal; Middleware System