A Model Prediction Control Method for Improving Transient Stability of Islanded Microgrid with Heterogeneous Micro-source under Large Disturbance

Distributed renewable energy sources are often connected to microgrid as virtual synchronous generators (VSG) operating in parallel with conventional synchronous generators (SG) to form a heterogeneous micro-source system (HMSS). In this paper, the oscillating equations of HMSS are established to analyze the transient instability mechanism under large disturbance. Furthermore, the additional torque control method based on model prediction is proposed. Also, the selection principle of main control parameters is given. To improve the system’s transient stability, the angular frequency and torque increment of HMSS are used as input variate to reduce the characteristic difference between micro-sources. Finally, experiment results are presented to validate the effectiveness of the proposed method.