What is an electrical substation and what functions does it perform?

A substation is a facility that switches, transforms, and regulates electrical power. Key functions include: voltage transformation (step-up or step-down), switching and routing power flows, protection (circuit breakers, fuses), voltage regulation (tap changers, capacitors), and metering. Substations range from small pole-mounted transformers to large transmission substations covering several acres with multiple voltage levels and complex switching arrangements.