Modern smart grids are held together by intelligent network substations that allow data to be sent and received in real time, tracking to be done from afar, and decisions to be made automatically. But as they get more complicated, they become more vulnerable to advanced cyber risks like data manipulation, denial-of-service attacks, and attacks from inside the company. This essay talks about some of the hardest things about keeping private operational data safe, focussing on flaws in communication methods, Internet of Things (IoT) devices, and cloud-based control systems. We look at advanced options like blockchain for keeping data safe, homomorphic encryption for safe computing, AI-powered intrusion detection, and zero-trust frameworks. The suggested methods show how next-generation substations can have resilience, dependability, and privacy protected by integrated security designs.