With the development of 5G technology and low-power wireless communication technology, a large number of IOT devices are introduced into energy systems. Existing IOT communication protocols such as MQQT and COAP cannot meet the requirements of high reliability and real-time performance. However, the 61850-9-2 Sample value protocol is relatively complex and the message length is large, difficult to ensure real-time transmission for IOT devices with limited transmission rate. This paper proposes a 9-2 Sample Value protocol for IOT controller based on Application Service Data Unit. The communication protocol is strictly in accordance with IEC61850-9-2 and can be recognized by existing intelligent electronic devices such as merging units. The protocol simplifies and trims some parameters, and changes the floating point value to integer data. Considering the instability of wireless communication, uni-cast or multicast UDP/IP is utilized to send SV Payload based on the 2.4GHz WIFI. The maximum transmission rate can be up to 30 Mbps. The hardware to implement reduced SV adopts ESP32-S, which is a dual-core MCU supporting WIFI with frequency of 240MHz. Software is based on FreeRTOS, LWIP and Libiec61850. A PC or raspberry PI is used as the Host to receive and analyze packets, verifying feasibility of reduced SV protocols.
翻译:由于开发了5G技术和低功率无线通信技术,大量IOT设备被引入能源系统,现有IPO通信协议,如MQT和COAP等现有IPO通信协议无法满足高可靠性和实时性能的要求,然而,61850-9-2样本价值协议相对复杂,信息长度很大,难以确保传输率有限的IOT设备的实时传输。本文件提议在应用服务数据股的基础上为IOT控制器制定一个9-2样本价值协议。通信协议严格遵循IEC61850-9-2,并可由现有智能电子设备(如合并单位)承认。协议简化和修饰了一些参数,将浮动点值值改为整数数据。考虑到无线通信的不稳定性,单式或多式UDP/IP用于发送基于2.4GHz WIFI的SV Payloadload:最高传输率可高达30Mbps。实施SV32-S的硬件采用SEV-S,这是支持WIFI的双核心MCUCU,以240MMHFS的频率接收和RAFI。