A Control Topology to Enhance Performance of Weak Grid under Different Power Levels

The main objective of this paper is to provide a new control topology for improving the performance of weak grid by damping power and frequency oscillations. To attenuate power and frequency oscillations, a linear controller is used based on droop characteristics. The controller has cascaded angle, frequency and power loops for frequency and angle regulation. The controller provides new control technique for VSC to damp power and frequency oscillations by automatically synchronizing the VSC to grid. The linear controller can also be suitable for both islanded and grid connected operation without reconfiguration. The controller offers stable and smooth operation. Also analysis of system performance at low and high-power references, transition to islanding, self-synchronization were carried out.