Novel Decentralized Pole Placement Design of Power System Stabilizers Using Hybrid Differential Evolution

This paper is used to investigate a novel decentralized pole placement design of lead-lag power system stabilizers using hybrid differential evolution (HDE). Since only local speed deviations are used as the feedback signals, the decentralized stabilizers could be easily implemented. It wants to place the electromechanical modes within a designated region to have enough damping. Participation factors are used to select the site and number of stabilizers. If all electromechanical modes have been moved to the specified region at the convergent step, the objective function will reach a minimal value. The objective function is chosen to ensure the real parts and damping ratios of electromechanical modes. A test power system is used to reveal the goodness of this method. Several operating points can be considered simultaneously in the determination of stabilizer parameters to let the stabilizers work well under a wider range of operating conditions. The computation time and convergence characteristic of this approach are better, compared to the differential evolution and genetic algorithm. The coherency measures are also proposed to evaluate the relative behaviours between any pair of generators of the system with and without stabilizers. Key-Words: Power system stabilizer, Electromechanical mode, Pole placement, Hybrid differential evolution, Power system dynamics, lead-lag power system stabilizers.