Real-time Submodule Communication Link Monitoring for MMC-HVDC systems

In this paper, we propose an online real-time optical link monitoring system (OLMS) that can monitor the operation status of submodules and their communication control circuit through real-time monitoring of the optical link status and up-and-down communication data frames, while maintaining stable data exchange between a set of submodules and the ARM controller in MMC-HVDC systems. The hardware implementation of the proposed OLMS system, the FPGA logic design, and the implementation results of the remote monitoring system for multiple OLMS boards through the web GUI node are introduced. From the implementation results, it is verified that alarms can be monitored for a total of 25 events, including submodule capacitance and temperature, from the upstream and downstream data frames of the optical link between the ARM controller and the submodule, which performs the down-control and up-monitoring data collection in several mu s cycles.