高低圧PV混在配電線のVolt-var制御による無効電力出力とSVR動作の適正化

Abstract

The voltage fluctuations that occur locally in the distribution system caused by high penetration of photovoltaic (PV) power generation based on the carbon neutrality strategy have been regarded as one of the serious operational problems. Assuming that larger amount of PV power sources will be connected in the future distribution system, Volt-var control of PV smart inverters is expected. This will enable more flexible and effective voltage control support by provide custom var response. The authors have investigated the effective voltage control of coordination between tap operation of Step Voltage Regulator (SVR) and Volt-var control of PV smart inverters. In our previous studies, we proposed a Volt-var curve determination method for MW-large-scale PV smart inverters connected to medium-voltage to decrease SVR tap operations and minimize distribution losses. However, there are uncertainties such as PV outputs and loads of low-voltage consumers that cannot be completely and individually determined from the measurements of medium-voltage PV smart inverters. In this study, using a detailed distribution line model that reflects actual power measurement datasets of individual low-voltage customers, effects of reduction in distribution losses, reduction in the number of SVR tap operations, and changes in cumulative reactive power output sharing of PV inverters are evaluated through simulation studies to confirm the effectiveness of the proposed Volt-var setting method.