Search for: All records

With the increasing integration of renewable energy, the problems associated with deteriorating grid frequency profile and potential power system instability have become more significant. In this paper, the inertial control algorithm using Virtual Synchronous Generator (VSG) is implemented on type-4 Permanent Magnet Synchronous Generator (PMSG) - wind turbine generator (WTG). The overall nonlinear dynamic model and its small-signal linearization of PMSG-WTG using VSG is established and comprehensively analyzed. Inevitably, the direct application of VSG introduces large inertia which causes conflict between the fast-varying of available wind power and inverter control with slow dynamics, particularly in region 2 of wind turbine. Aiming to address such issue, VSG with multiple virtual rotating masses is proposed in order to improve the active power tracking performance as well as to boost inertial control of a VSG. The inertial responses are verified in a modified 10MVA IEEE 14 bus microgrid system. The assessment of the simulation results demonstrates the applicability of VSG on renewable energy generation units. 

In this paper, the small-signal model and stability-oriented consensus control scheme for inverter-based microgrid systems is proposed. By perturbating four identified dominant control parameters of inverter-based microgrid intentionally, the corresponding incremental matrix of microgrid system can be formed. Then, Matrix Perturbation Theory is employed in this paper to reduce the computational burden caused by repetitive calculations of system eigenvalues during stability analysis. Furthermore, the objective function is formulated based on the small-signal stability index and consensus index of microgrid system. Finally, the optimal control algorithm based on the joint application of Matrix Perturbation Theory and Artificial Fish Swarm Algorithm is introduced in this paper so that the stability and consensus rate of microgrid can be ensured. Besides, the effectiveness of proposed method can be verified in Matlab/Simulation results.