Adaptability of PSS while the connection between Northeast and North Grids of China changed from AC to DC

In this study, the influence of either AC or DC interconnection on the dominant oscillation mode and the frequency response of generator were conducted. Also conducted was the adaptability of PSSs to AC or DC connection of the North East China Grid (NECG) and the North China Grid (NCG). Both complex frequency domain and time domain methods were employed. For analyzing small disturbance stability, not only the dominant area modes but also the local modes were studied in detail. . Based on the above studies, Power System Stabilizer (PSS) adaptability to different connections of the two power grids was demonstrated. The results demonstrate that the present PSS setting of NECG for AC connection with NCG can meet the normal operating requirements for the DC connection.