Value Comparison between FRT and DVS Functions on Renewable Energy

Abstract

Although FRT capability is claimed in Japanese grid code for RE, DVS capability is not. In some European countries, not only FRT but also DVS is claimed. Whether this choice of our grid code is pragmatically adequate or not? To answer the question, it is necessary to evaluate FRT and DVS capabilities. But the past studies only evaluated qualitative merit of FRT and DVS, or evaluated quantitative merit on fictional system models. Since the authors intend to evaluate FRT and DVS capabilities in existing power system of Japan, some method for the evaluation must be invented. For the evaluation, values of FRT and DVS capabilities are evaluated by reduction amount of stabilizing equipment (i.e. SVC in the paper). The evaluation based on strict optimal SVC disposition is quite difficult, because existing power system must be adequately modeled, because number of SVCs is large and because every power flow conditions must be considered. However, semi-optimal SVC disposition can be calculated as shown in the paper. As the result, value of FRT is quite larger than value of DVS. And then, our grid code is proved as pragmatically adequate, except some flaw in claimed FRT design that is introduced in the paper. K E Y W O R D SDVS, FRT, grid code, induction motor load, power system, renewable energy 1. Evaluation must be applied not to just a simple system model, but to one that appropriately describes real systems. 2.Optimal SVC allocation to maintain system stability must be determined for faults that may occur anywhere in the Electr Eng Jpn. 2018;205:33-40.