PD IEC TS 60076-20:2017

FOREWORD
INTRODUCTION
1 Scope
2 Normative references
3 Terms and definitions
4 Efficiency and efficiency index calculation
5 Specification of energy performance
6 Energy performance levels
7 Tolerance
Annex A (informative) - Capitalisation of losses
Annex B (informative) - Efficiency based on a survey
        of world practices
Annex C (informative) - Japanese practices
Bibliography

Provides methods of specifying a transformer with an appropriate level of energy efficiency according to the loading and operating conditions applicable.

This part of IEC60076 is applicable to transformers in the scope of IEC60076-1.

The energy performance levels given in Clause6 are not applicable to the following transformers:

• transformers for high current rectifiers as described in the IEC61378 (all parts) and in the IEC60146 (all parts);

• transformers for furnace applications;

• transformers for offshore applications;

  NOTE1 Transformer to be installed on fixed or floating offshore platforms, offshore wind turbines or on board of ships and all kind of vessels).

• transformers for emergency or temporary mobile installations;

  NOTE2 Transformers designed only to provide cover for a specific time limited situation when the normal power supply is interrupted either due to an unplanned occurrence such as failure or a station refurbishment, but not to permanently upgrade an existing substation.

• traction transformers;

• earthing transformers as described in 3.1.10 of IEC60076-6:2007.

• phase shifting transformers;

• instrument transformers (IEC61869-1);

• transformers and auto-transformers specifically designed for railway feeding systems, as defined in EN50329;

• traction catenary supply transformer for 16,67Hz;

• transformer for high current rectifiers (IEC61869-1);

  NOTE3 These are transformers specifically designed and intended to supply power electronic or rectifier loads specified according to IEC61378-1.

  NOTE4 This exclusion does not apply to transformers intended to provide AC power from DC sources such as transformers for wind turbine and photo voltaic applications as well as transformers designed for DC transmission and distribution applications.??

• transformers for railway feeding systems (EN50329);

• subsea transformers;

• starting-, testing- and welding transformers;

• starting transformers, specifically designed for starting three-phase induction motors so as to eliminate supply voltage dips;

  NOTE5 Examples are transformers that are de-energised during normal operation, used for the purpose of starting a rotating machine).

• transformers specifically designed for explosion-proof and underground mining applications;

• transformers which cannot fulfil the energy performance requirements due to unavoidable size and weight limitations.

  NOTE6 Due to the unavoidable weight and size limitation for a rolling stock application, this definition includes all traction transformers for rolling stock, irrespective of the frequency (e.g. 16,7Hz, 25Hz, 50Hz, 60Hz).

In this document, \'transformers\' includes both separate winding transformers and autotransformers.

NOTE7 Transformers intended to provide AC power from DC sources such as transformers for wind turbine and photo voltaic applications as well as transformers designed for DC transmission and distribution applications are included in the Scope of this document.