Control of low-frequency oscillations in grid-connected power system for wind-PV-thermal-electricity energy system

In this paper, a new swarm intelligent optimization algorithm named DTHA is proposed for the low-frequency oscillation (LFO) problem generated in the wind-PV-electricity (WPTE) energy system. According to this algorithm, the coordinated optimization control of the power system stabilizer (PSS), power oscillation damping (POD) controller, and thyristor controlled series capacitor (TCSC) parameters are carried out. In this paper, the effectiveness and robustness of the method are verified using the IEEE four-machine two-zone system as an example. The results show that the technique can effectively keep the generator speed stable, suppress the system’s active and voltage fluctuations caused by LFO, and improve the small disturbance characteristics of the system.