An Online Monitoring Scheme for the Earth Resistance of a Common Earth Electrode

High-voltage direct current (HVDC) transmission is ideal for long-distance, large-capacity power delivery. A DC common earth electrode can be used for multiple DC lines, reducing the difficulty of land acquisition and lowering investment in grounding leads in power construction. The operating conditions of DC common earth electrodes are complex, and variations in earth resistance can cause ground potential rise (GPR), excessive step voltage, and other safety hazards. This paper proposes a technical scheme for online monitoring of DC earth resistance, verifies its feasibility through simple simulations, and finally validates the monitoring scheme using actual engineering parameters of the CH common earth electrode project through simulation. This study provides ideas and technical guidance for multiparameter monitoring of DC common earth electrodes and offers data to support the online monitoring of similar electrode groups.