Directional Overcurrent Protection Test in AMR Relay (Simple Test Using Templates)
Imported Content
After connecting to the AMR relay at first, simply load the device's hardware configuration from the Device menu by selecting the Read Hardware from Relay option.
The default password is 123456 in order to receive elements.
At this point, a message is given to remove the signal, which if confirmed, if the current hardware is not the same as the relay hardware, the current hardware signals used in the VFC section are deleted.
It should be noted that the settings for the conversion ratio of voltage and current transformers are determined in the related card. Here the ratio of current card conversion is 200A to 1A.
(First, enter the VFC page): As mentioned earlier in the AMR software, configuring some of the most widely used functions as examples are placed in the software and the user can send new settings to the relay by selecting each of them and applying the desired changes. For this purpose, a set of functions can be seen in the Relay VFC tab and in the Temp Functions section. It should be noted that by selecting each Temp Function, the blocks in the VFC are removed.
Here the directional overcurrent function displayed with the name OC 67 is selected. In Configuring, this function uses an OC Inverse block and two OC Definite blocks that have different settings and the signals of a current card are assigned to their input (from a measuring point). Finally, output signals are assigned to Binary Outputs and relay LEDs by Output and LED blocks.
To change the settings, simply right-click on each block to access a set of options.
Finally, the changes are sent to the relay.
In this video, by double-clicking on blocks that contain constant time stages for the directional overcurrent function, disables them
and define the 1A and TMS current settings equal to 0.1 by double-clicking on the first stage, which is defined as reverse time. By double-clicking on the Direction block, the elements related to the directional function include rotation angle and ground polarization.
After this, the changes will be sent to the relay by selecting send config and setting to relay option.
In the
next step, by running AMPro software and opening the AMT Overcurrent room, it
is enough to go to the Object Parameters test section and create the test characteristic
after entering the information.
Keep in mind that it is also possible to
test this function using the Xrio file. Here, the current setting value is
equal to 1 amp, TMS is 0.1.
In the overcurrent test, it is required to set two
parameters maximum torque angle and sector operation. To do this from the
Overcurrent window and the Relay Parameters tab, the directional option is
selected
and from the Element tab, the Directional section is placed on
forward. Then enter under the Define Element Directional Behavior tab and the
maximum torque angle and Sector operation parameters are equal to -45 and 172
degrees, respectively.
In directional
overcurrent relays, In order to better performance of relay, in orientation and
reaching the MTA value ,the rotation of the reference voltage angle is used..
The performance area or forward area in this relay is set from -131 degrees to
+41 degrees. In order
to investigate the directional overcurrent function, in addition to the time of
operation and current, the angle of performance should also be investigated.
For this purpose, performance time tests are performed along with amplitude and
phase tests. In the
time test, the accuracy of the performance time is investigated and in the
amplitude and phase test, the detection and evaluation of the accuracy of the
actual current and the actual angle of the performance threshold and reset
threshold are considered. Cross Polarized
method is used in AMR Vebko relay, i.e. using healthy phases to detect fault
direction. For example, in case of faults in phase A, the relay uses VBC
reference voltage and IA current to detect the fault current direction. The
Forward or Reverse area means the part where the relay must detect the fault
will be determined by the start angle and end angle. In order
to test the DOC function, three states are considered. The first state for 500
milliseconds, normal conditions this means that it will inject a nominal
voltage with zero current. In the
second state, the fault conditions are applied and the current is selected for
all phases of L1E-L2E-L3E in the range of 2 to 4 times the nominal current. The
duration of this state should be greater than the nominal time of the relay
trip.
The
third state will also be activated as post-Fault with zero voltage and current
for 500 milliseconds. In order to see better performance of the function, from
the View menu, the Detail View window opens.
After
adding double points and four times the regulatory current at the best possible
angle in terms of performance of the function i.e. -45 degrees for the
L1E-L2E-L3E falt types, a point in the No Trip area (here at an angle of 135
degrees) is tested.
Due to
the nature of the two-phase fault, the currents in this fault will have a phase
difference of 180 degrees so that the 3I0 current is not created and the 67N
function is not activated. In order
to perform the Pickup-Drop off test, you can also use a relay or LED contact
and even a setting change to instantaneous the function. For this
purpose, three states are needed for example in the first state, the normal
network conditions, applied, in the second state the pickup test and in the
third state the drop-off test is performed. In the second state, for pickup and
drop-off test of angle, the current value will be twice the regulatory current.
these states are performed in the Overcurrent room automatically by entering
the settings by the user.
The
performance range of overcurrent curves in the AMR relay starts from 1.1
regulatory current in the relay. Therefore, first, by enabling the Active Range
Limits option in the Overcurrent Protection Parameters window, the Imin value
is set to 1.1 Iref.
In the next step, the current adjustment value for the
pickup test of the current value is placed on 1.1*1=1.1 amps. This test is
performed at the best possible angle in terms of relay performance i.e. -45
degrees.
After
the current pick up-drop off, it is time to Pick up-drop off on the angle. For
this purpose, as mentioned above, the current value is applied twice as much as
the regulatory current, and once the trend is performed for the upper limit of
the angle, i.e. 41 degrees, and once for the lower limit of the angle, i.e.
-131 degrees.
By adding the necessary tests and performing, you can
finally add favorites items to the report.
[jg1]Directional_overcurrentTest Test
Pickup-Drop off Test
