There is an increasingly high level of requirement for high-speed smart substation data processing. Based on multi-core SoC and FPGA hardware and SylixOS embedded real-time operating system software scheme, this paper studies distributed, multi board relay protection device platform technologies. High-speed front-end data processing design of an FPGA is proposed and the LVDS high-speed bus and real-time CAN bus communication technology for multi board interconnection are discussed. A scheme of accurate clock synchronization of multi boards and sampling synchronization is proposed. Based on an asynchronous multi processing (AMP) software model, the architecture of multi-core and multi task parallel processing is studied and a technical scheme to improve reliability of the device is proposed. This employs data mutual checking between multi boards. Finally, based on the software and hardware technologies proposed, a series of relay protection devices that apply fully domestic components are developed and tested. The reliability and advantages of our independent and controllable technical solution are verified by field trial operations. This work is supported by the National Key Research and Development Program of China (No. 2018YFB2100100).