OMICRON

Advanced Differential is a set of test modules which form a complete testing solution for differential schemes. It is particularly suitable for transformer differential schemes with up to 3-windings and up to nine currents to be injected.

Extensive modeling of the protected object (e.g. power transformer), the secondary equipment (CTs, CT connection) and the relay characteristics provides the data for the calculations required to facilitate testing. The automatic calculation of the test currents eliminates the most time consuming and error-prone manual tasks.

Features

• Testing with all fault types (L-N, L-L, L-L-L)
• Shot tests at pre-defined test points or search tests
• All shots synchronizable to GPS or IRIG-B for end-to-end testing (e.g. line differential protection)
• Evaluation and assessment of results against nominal characteristics and tolerances
• Report generation including graphical representation of the results in the characteristic diagrams
• No blocking of voltage related functions required (important for testing of multifunctional relays)
  
  

For transformers, automatic calculation of currents to be injected are based on:

• Transformer data (nominal data, vector group)
• CT ratios and connections
• Fault type
• Fault/supply side (primary, secondary, etc.)
• Load current
• Amplitude and phase correction
  
  

For the protective relay, the assessment of the measured values is based on:

• Operating characteristic
• Bias calculation
• Zero sequence elimination