This section shows how to run the simulation and view the results for each scenario. The fault at BT bay will trigger at 0.2 seconds for 0.2 seconds. Depending on the protection scenario that is selected, the breaker operation at BT, IncA, and IncB bays are shown in this section.
The simulation should be run in steady state so make sure the network is initialized by the load flow.
- Open Network → Load Flow, make sure the frequency is at 60 Hz and then press "Execute load flow".
You can also enable performing load flow when simulation starts in the "Simulation Settings".
- Run the simulation in real time on a target in real time.
Scenario 1: Reverse Blocking (RB)
Fault occurs at 0.2 seconds at BT. Fault is seen by both BT_PU and IncA_PUBCU. BT_PU sends tripping signal to CB_BT and it opens successfully. BT_PU blocks IncA_PUBCU from sending a trip signal to CB_INCA so it does not open.
- Open Template IEC61850_SAS_MMS.svt from the project folder.
- Open ScopeView, click on both Sync and Trig to make sure fault is triggered at 0.2 seconds.
- Do an acquisition by pressing on the Play button on that ab "BT_Relay_Fault"
From the diagrams in this tab, the overcurrent relay at BT_PU IED sees the fault current at 0.2 seconds and issues a trip signal after 0.05 second delay (0.05 seconds is its protection relay setting). In the Reverse Blocking scenario, breaker CB_BT receives the trip signal from the relay and opens at 0.25 seconds.
- Open the page "Scenario1: Reverse Blocking (CB_INCA)". This page shows the publishing of GOOSE message containing the data attribute PTOC.Str.general when the relay at BT has issued the tripping signal at 0.25 seconds. This message is sent to IED at IncA. By viewing the operation of CB_BT and CB_INCA, it can be seen that, as expected, CB_BT is open at 0.25 seconds and CB_INCA is blocked and has stayed closed during the fault period.
Scenario2: Breaker Failure (BF)
Fault occurs at 0.2 seconds at BT. Fault is seen by both BT_PU and IncB_PUBCU. BT_PU sends tripping signal to CB_BT and but does not open. IncB_PUBCU sends trip signal to CB_INCA and it opens instead.
- Make sure the simulation is running and open ScopeView. Make sure the template IEC61850_SAS_MMS is open, view the page BT_Relay_Fault, and do an acquisition.
In this scenario, the overcurrent is seen by the relay and it issues a tripping signal but as it is shown, the breaker CB_BT does not receive the message and so the breaker fails to open.
- View the page "Scenario2: Breaker Failure (CB__INCB)". The GOOSE message containing the data RBRF.OpEx.general is published to the bay INCB. As it can be seen, the breaker at BT has failed to open and remained closed. So, the IED at INCB has issued a signal to its breaker CB_INCB to be open instead. It can be seen that at 0.25 seconds, the breaker CB_BT is closed and CB_INCB has opened and thus isolated the fault and protected the busbar.
Scenario3: MMS Control
Fault occurs at 0.2 seconds. It is seen by IncB_PUBCU and its overcurrent relay sends trip signal to breaker CB_INCB. Trip time and breaker operation time can differ based on relay setting group (SG). The setting group can be changed between 1 and 2 by MMS Client.
- Make sure the simulation is running, open ScopeView template SAS_IEC6150_MMS.svt. View the tab Scenario3: MMS Control.
This tab shows the output of the overcurrent relay at IncB_PUBCU. The relay sees the fault and issues a tripping signal to CB_INCB. The trip time depends on the relay setting groups. The graph SG1: Definite Time Overcurrent in this page shows the relay's trip time according to Setting Group 1 (SG1) . The time is about 0.3 seconds which corresponds to the 0.1 second delay of the relay's setting, as shown in IncB_PUBCU Relay Setting Groups. The graph CB_INCB Status shows the breaker CB_INCB opening with this time.
- Use an MMS client to change the setting group to 2. The picture below shows how it can be done using the free MMS client called "IED Explorer". You can view the part Using IED Explorer from Additional Information to learn how to use IED Explorer to change Setting Groups. View the same tab.
- Once the setting group has changed by the MMS client, do an acquisition in ScopeView to see the new results.
As it can be seen, the graph SG2:Inverse Time Overcurrent shows the relay's trip signal when Setting Group 2 (SG2) is selected. The time is approximately 0.36s which corresponds to the expected time shown in IncB_PUBCU Relay Setting Groups. As seen from the graph CB_INCB Status, the breaker CB_INCB has opened at 0.36 seconds.
MMS reports and data
- View the diagrams in the tabs MMS(IncA_PUBCU) and MMS(IncB_PUBCU) in ScopeView. They show the data that is transmitted to the MMS client. The analog signals are current phasor magnitude and angles. The binary signals are those from logical nodes for either overcurrent protection (PTOC) or breaker failure (RBRF). Both analog and binary data are sent to the MMS client via Reports.
The following diagrams are taken during Scenario1: Reverse Blocking. The values are the same for all scenarios.
NOTE: As it can be seen from both pictures, MMS report for IncA_PUBCU contains data for phasor magnitudes and angles while reports for IncB_PUBCU only contain phasor magnitudes. This is because of the data model for each IED and depends on how they were designed.
This information can also be seen on an MMS client. On the client, the reports that are sent by the MMS servers (IEDs in the model) can be viewed, enabled and their data sets can be monitored with values changing during the simulation runtime.
The pictures below show the report control blocks and monitored data of the measurement from IncA_PUBCU IED on the application IED Explorer. To know how to use IED Explorer to view this data, read section Show Reports and Data Sets on this documentation.
The first picture shows the IED's current phasor measurement during normal operation and the second picture shows the phasors during fault. As it can be seen, the current phasor magnitudes are very high.
The next two pictures shows data from binary overcurrent protection signal and measurement from IncA_PUBCU IED on the application IEDScout. The first picture is normal operation and the second one is from the exact moment the fault occurred, As it can be seen, the current magnitudes are very high.
GOOSE and SV additional data
- View the pages "BF GOOSE data", "RB GOOSE data" to find data such as status number and sequence number for GOOSE publisher and subscriber of the two Reverse Blocking and Breaker Failure applications.
- stNum (Status Number) for publisher and subscriber: This data attribute increments whenever the status of the GOOSE message changes. So, in the case of the protection functions in this model, whenever the output of the relay BT_PU.5051OC (Q) changes its status, this number increments by 1. If a connection between publisher and subscriber is maintained, stNum for both publisher and subscriber should be the same value.
- sqNum (Sequence Number) for publisher and subscriber: This data attribute increments whenever the GOOSE message is retransmitted which differs for each GOOSE control block. It rests to 0 or 1 (depending on the GOOSE control block parameters). So, in this model, whenever the fault is reinitialized and the relay output changes its status, sqNum resets to 0. sqNum should be the same for both publisher and subscriber as long as their connection is established and maintained.
- State for subscriber: This data attribute has the value of 1 when the connection between publisher and subscriber is established. If they lose connection, the value drops to 0. If subscriber falls out of sync with the publisher (so it is not following it anymore). the value changes to -5.
As shown in the picture, the values for stNum, sqNum for both publisher and subscriber are the same. As it is explained, stNum increments every time there is a change in data which in this case, is when fault occurs and is cleared by doing the acquisition in ScopeView. Also, sqNum shows it drops to zero every time fault occurs or clears by pressing the acquisition. It increments again constantly until the acquisition is pressed again. State = 1 so a connection has been successfully established between GOOSE publisher and subscriber.
NOTE: The values shown in the diagram for both stNum and sqNum could be different on your ScopeView since it depends on what values they had and how long the simulation was running before the acquisition.
- Open the tab SV Data to view Sampled Value streams quality and the Sample Value count of the OPALRT_BTMU stream.
The SV Publisher and Subscriber Quality waveforms are taken from the constant blocks SVPub_Q which are publishing the quality value for current SV streams. If the subscriber values are the same as the publisher values, as shown in the figure, it means the connection between the publisher and subscriber is valid.
SV Sample Count shows the smpCnt value of the SV stream. This data attribute is typically used for synchronization validation. According to the standard, an IEC 61850-9-2 LE compliant merging unit can publish analog data at a fixed rate which is 80 samples per power cycle. The number of samples per second is 4800 for a 60 Hz system (like this model) and 4000 for a 50 Hz system. The figure shows how smpCnt reaches 4800 in one second.