IEEE PSS4B implementation in Static Excitation System and Hardware-in-Loop Testing with RTDS

Significant integration of renewable energy sources with conventional thermal, hydro and nuclear power poses several operational challenges to grid operators. Small signal instability caused by electro-mechanical oscillatory modes is one such example. Oscillations of considerable magnitude are being frequently witnessed in India by the operators in recent years. Power System Stabilizers (PSS) play an important role in the interconnected systems to damp out the spurious oscillations. Multi band power system stabilizer (MB-PSS), also known as IEEE-PSS4B, can be more effective than the conventional speed input and dual input PSS. In this paper implementation of IEEE-PSS4B in the BHEL static excitation equipment (SEE) controller is discussed. The effectiveness of the PSS4B is tested using hardware-in-loop testing with RTDS. A single machine infinite bus system and a 5 generator 10 bus system is simulated in RTDS. One of the generator's excitation system is replaced with SEE hardware in a closed loop configuration. The real-time simulation results under small and large disturbances are provided to show the effectiveness of the PSS4B functionality enabled in the SEE.