Compensation Method of Communication Delays and Failures to ReducePower Fluctuations in Micro Grid

ABSTRACT In this paper, photovoltaics (PV) outputs are not only limited constantly but also controlled by bidirectional communications to compensate short period power fluctuations. In this case, if qualities of communication systems are not high, communication delays may not be ignored. The effect of communication delays is evaluated. If communication delays are not very small, a system reaches a stability limit, and a PV output may oscillate continuously. Then, a compensation method of them is proposed. The compensation method uses a disturbance observer. In this method, it is a merit that models of communication delays are not necessary and only a PV output model is necessary. It is found that the proposed method can compensate communication delays to some extent by simulating step responses. Furthermore, compensation of short period power fluctuations in a micro grid is considered by using the proposed method. Short period power fluctuation may be reduced by the compensation method of communication delays