Hello,
We have Siemens RG3 T4s excitation system installed at our power plant with steam turbine. It was operating at 72MW and 75MVArs and suddenly it goes upto 93 Mvars, and generator protection relay gives a command to control system to close the main valve and trip the machine as well as GCB. The terminal voltages of generator goes to 11.57kV while rated terminal voltages are 10.5kV and V/f setting was 2. 42 for 1 second which was met and protection relay operated.
Now I have some questions:
1 Will the Over excitation limiter did not come into service? How can I Check this in RG3 controller? Anybody have a guide?
2. AVR was on volt control mode. Is this the reason which may increase the Mvars to maintain terminal voltages? Because at that time grid voltages were less around 125kV in 132kV system
We have Siemens RG3 T4s excitation system installed at our power plant with steam turbine. It was operating at 72MW and 75MVArs and suddenly it goes upto 93 Mvars, and generator protection relay gives a command to control system to close the main valve and trip the machine as well as GCB. The terminal voltages of generator goes to 11.57kV while rated terminal voltages are 10.5kV and V/f setting was 2. 42 for 1 second which was met and protection relay operated.
Now I have some questions:
1 Will the Over excitation limiter did not come into service? How can I Check this in RG3 controller? Anybody have a guide?
2. AVR was on volt control mode. Is this the reason which may increase the Mvars to maintain terminal voltages? Because at that time grid voltages were less around 125kV in 132kV system