Optimal PID controller of large‐scale PV farms for power systems LFO damping
Mahdi Saadatmand, Babak Mozafari, Gevork B. Gharehpetian, Soodabeh Soleymani
Abstract
The penetration of large-scale photovoltaic farms (LPFs) is ever increasing. Given that LPFs are added to power systems or replaced by conventional power plants, they should undertake the most common tasks of synchronous generators. One of these tasks is the low-frequency oscillation (LFO) damping using power system stabilizer. This paper proposes a general method for LFO damping using LPFs by designing an optimal proportional-integral-derivative (PID) controller as a power oscillation damper in the nonlinear control loop of LPF. Considering the need for a valid LPF model, therefore the second generation generic model, developed and approved by western electricity coordinating council, is used. The PID controller is optimally tuned using the particle swarm optimization algorithm in order to produce an effective LFO damping. Finally, the performance of this controller is investigated in the modified two-area test system, showing the proper performance of the LPF for LFO damping using the proposed optimal PID controller in the various operating condition and different short circuit ratio values.