Positive and Negative Sequence Control Strategies to Maximize the Voltage Support in Resistive-Inductive Grids During Grid Faults
Rights accessOpen Access
Grid faults are one of the most severe perturbations in power systems. During these extreme disturbances, the reliability of the grid is compromised and the risk of a power outage is increased. To prevent this issue, distributed generation inverters can help the grid by supporting the grid voltages. Voltage support mainly depends on two constraints: the amount of injected current and the grid impedance. This paper proposes a voltage support control scheme that joins these two features. Hence, the control strategy injects the maximum rated current of the inverter. Thus, the inverter takes advantage of the distributed capacities and operates safely during voltage sags. Also, the controller selects the appropriate power references depending on the resistive-inductive grid impedance. Therefore the grid can be better supported since the voltage at the point of common coupling is improved. Several voltage objectives, which cannot be achieved together, are developed and discussed in detail. These objectives are threefold: a) to maximize the positive sequence voltage, b) to minimize the negative sequence voltage, and c) to maximize the difference between positive and negative sequence voltages. A mathematical optimal solution is obtained for each objective function. Experimental results are presented to validate the theoretical solutions.
CitationCamacho, A., Castilla, M., Miret, J., Garcia de Vicuña, J., Guzman, R. Positive and Negative Sequence Control Strategies to Maximize the Voltage Support in Resistive-Inductive Grids During Grid Faults. "IEEE transactions on power electronics", 27 Juliol 2017, vol. 99, p. 1.