Directional Overcurrent Relay

The Overcurrent relay characteristics can be described with the formula:

For trip-time :

For reset-time :

Fixed-float types

Functions:

These are few utility functions implemented. The file has a function (self-implemented) to print the signals (std_logic_vectors) to ISim console while running simulations through ISE.

Types:

This package has a basic definition of decimal point numbers which apply to both fixed-point and floating-point numbers.

Fixed Package:

The v0 package implements fixed-point numbers. These are not yet made synthesizeable as they aren't needed yet in the DOCR module. The normal version is empty package, so it may be used for now.

Float Package:

This package has various mathematical functions implemented for calculation of tripping time and reset time of the relay. This has a (sel-implemented) synthesizeable power (exponentiation) function for calculating a float number raised to a signed-fixed number exponent.

Check and t-Check:

These are temporary module and test-bench for testing of implemented functions.

References:

SOPC design for implementation of overcurrent relay