Transformers are one of the most important and high CAPEX assets for Electric Utilities. They are normally designed and built for use at rated frequency and perfect sinusoidal load current. However, with advances in modern electrical systems, there is a sudden increase in proliferation of non-linear loads such as power supplies rectifier equipment, domestic appliances (computers, UPS systems, etc.), adjustable speed drives, etc. These non-linear loads draw non-sinusoidal currents and cause voltage and current distortion called harmonics.

The transformer is also one of the key equipment which interfaces between supply and most non-linear loads. For e.g. According to Strategies for development and diffusion of Energy Efficient Distribution Transformers (SEEDT), the losses caused by harmonics are estimated at about 5000 GWh/year. The harmonic currents cause a small increase in winding losses; and, the high-frequency harmonic voltage cause large core losses leading to early fatigue of insulation, premature failure and reduction of the life of the transformer. Therefore, harmonic analysis with loss calculation plays a vital role in transformers to reduce harmonics effect.

In simple words, loss calculation means, when ordering/purchasing a transformer, certain acceptable levels of core and winding losses are agreed between the client and the manufacturer. However, actual loss levels are subject to some variation in the production process. Hence, when purchasing transformers, it is important to compare the cost of the losses over the entire lifetime of the various types considered.

This webinar brings an expert from an energy industry sharing his views on assessment of transformer losses in harmonics high environment with the help of ‘Transformer Loss Calculation Tool’.