On-load tap changers (OLTC)

This course provides a structured and comprehensive understanding of on-load tap changers (OLTCs), combining operational principles, construction concepts, switching technologies, diagnostics, and advanced testing methodologies into a single engineering-focused programme. Rather than treating OLTCs only as transformer accessories, the course explains their central role in voltage regulation, transformer reliability, and power-system stability under real operating conditions.

A strong emphasis is placed on practical diagnostics and interpretation of dynamic resistance measurement (DRM) results, including resistor-type and reactor-type OLTCs, special configurations, synchronization assessment, and advanced troubleshooting. The programme integrates electrical, mechanical, oil-based, and vibro-acoustic diagnostic approaches, reflecting real industrial maintenance, commissioning, and condition-assessment practices used by utilities, service providers, and transformer manufacturers.