Location

This example model can be found in the software under the category "Benchmarks" with the file name "HVAC_230kV_6Bus.ecf".

Description

The HVAC 230kV 6Bus transmission system model can be used to evaluate electromagnetic transient overvoltage caused by line switching, fault initiation, and clearing. This benchmark model contains two synchronous machines with built-in voltage and speed regulators, one voltage source and four two-winding transformers, and six constant parameters lines and works at three voltage levels 13.8 kV, 110kV, and 230 kV.  For this transmission example, three three-phase faults are considered on different buses. The fault times can be modified as required by the user, and new faults can also be added on other buses.

Figure 1: Synchronous machine configuration settings

Simulation and Results

As part of the example model setup, the user can perform three types of scenarios. The user can enable or disable three three-phase faults on different model buses.

Scenario 1: Three-phase fault on Bus 7x

The first scenario is about introducing a three-phase fault on Bus 7x at 0.1s by 0.1s. This scenario gives the user an idea of reliability in power systems, and how it reacts after clearing a fault. The user can change these settings by going into the fault subsystem and changing the values of T1 and T2, configuring the fault activation and clear times, respectively. By default only this fault is enabled,  it is necessary to check the Enable option within the fault subsystem called Fault1 and also check the disable option within the faults subsystem called Fault2 and Fault3. 

Figure 2: Fault configuration settings

The following are the results from ScopeView following the first scenario, a three-phase fault on Bus 7x.

Figure 3: Bus Voltage and Fault current with a three-phase to ground fault at Bus 7x

Figure 4. Machine Terminal Voltages and Speeds with a three-phase to-ground fault at Bus 7x

Scenario 2: Three-phase fault on Bus 6x

The model is also equipped with a three-phase fault on Bus6x. Similar to scenario 1, the default times for this fault are set to activate at 0.1s and clear 0.1s later. By default this fault is disabled and only the three-phase Fault1 described in the scenario1 is enabled. To activate only this fault it is necessary to check the Enable option within the fault subsystem called Fault2 and also check the disable option within the faults subsystem called Fault1 and Fault3. 

The following are the results from ScopeView following the three-phase fault on Bus 6x.

Figure 5: Bus Voltage and Fault current on Bus7x with a three-phase to ground fault at Bus 6x

Figure 6. Machine Terminal Voltages and Speeds with a three-phase to-ground fault at Bus 6x

Scenario 3: Three-phase fault on Bus 11

The model is also equipped with a three-phase fault on Bus11. Similar to scenario 1 and scenario 2, the default times for this fault are set to activate at 0.1s and clear 0.1s later. By default this fault is  Disabled. To activate only this fault it is necessary to check the Enable option within the fault subsystem called Fault3 and also check the disable option within the faults subsystem called Fault1 and Fault2. 

The following are the results from ScopeView following the three-phase fault on Bus 11.

Figure 7: Bus Voltage and Fault current on Bus7x with a three-phase to ground fault at Bus 11

Figure 8. Machine Terminal Voltages and Speeds with a three-phase to-ground fault at Bus 11