Design of adaptive damp control considering the stochastic drifting of power system operating point caused by grid-connected wind power

The phenomenon of stochastic drifting of system operating point caused by grid-connected wind power is more and more prominent, the limitation of the traditional damping controllers are exhibited. Therefore, the adaptive control is proposed in this paper for tracking the stochastic drifting behavior of the operating points and switching the controllers adaptively. Firstly, the concept of stochastic drifting behavior is illustrated, and the damping is analyzed in the stochastic drifting circumstances. Also, the space of operating point is partitioned into several subspaces through the partitions of the stochastic output of wind power and the coordinated PSSs are designed by the mapping rules from subspaces of operating point to the stability space. Then, the optimum classification and regression decision tree (CART) is employed to classify different operating points. Finally, the on-line measurements from phasor measurement units (PMUs) are sent to CART for regression and track the stochastic drifting behavior and put the matched power system stabilizers (PSSs) into service adaptively. The simulation results of 16-genrator-68-bus system with large-scale grid-connected wind demonstrated that the proposed adaptive control scheme based on CART is able to damp the multiple oscillation modes effectively when the power system is operating at a wide range of output of wind power.