Substations are critical components of the power network, serving as junctions between transmission and distribution systems. Regular inspections of substation equipment are vital for ensuring their safe and stable operation. This study proposes a novel navigation method for substation inspection robots based on a multi-sensor fusion graph optimization Cartographer SLAM (Simultaneous Localization and Mapping) algorithm. The method integrates the Cartographer SLAM algorithm with multiple sensors to achieve precise map creation and positioning. Additionally, a Model Predictive Control (MPC) algorithm is employed to ensure safe and efficient inspection along predetermined paths. Experimental results demonstrate that the proposed method significantly enhances inspection efficiency and safety, offering new technological support for substation management.