Understanding Efficiency in Electrical Transformers-3 — Lesson 6

This lesson covers the concept of efficiency in transformers, focusing on power efficiency and energy efficiency. It explains how efficiency varies with the degree of loading and power factor. The lesson also discusses the concept of maximum efficiency and how it occurs at a specific load and power factor. It further elaborates on the impact of varying the power factor on the efficiency versus load curve. The lesson introduces the concept of all-day efficiency, which considers the energy output over 24 hours and the energy losses due to copper and core losses. It emphasizes that the all-day efficiency is a more practical measure for distribution transformers, given the varying load patterns.

Video Highlights

00:30 - Explanation of power efficiency and its relation to degree of loading
01:30 - Discussion on maximum efficiency and its occurrence
22:10 - Introduction to all-day efficiency
30:29 - Calculation of all-day efficiency considering energy output and losses

Key Takeaways

• The efficiency of a transformer varies with the degree of loading and power factor.
• Maximum efficiency occurs at a specific load and power factor.
• Varying the power factor impacts the efficiency versus load curve.
• All-day efficiency is a more practical measure for distribution transformers as it considers the energy output over 24 hours and the energy losses due to copper and core losses.
• The all-day efficiency calculation requires information about the load pattern, degree of loading, and power factor over different time intervals.