Active and reactive power coordination control strategy of overvoltage for distributed PV integrated grid

摘要

Aiming at the voltage rise due to the photovoltaic generation system (PVGS) at the point of common coupling (PCC), the cause is analysed with power transmission theory. Here, the principle and strategies of voltage regulation based on active and reactive power in PVGS are proposed. In this control strategy, the voltage of PCC is tracked by PV system in real time. When the voltage of PCC is normal, inverter will output in the way of maximum power point tracking (MPPT).When the voltage of PCC exceeds the upper limit, the inverter will regulate the voltage using the remaining capacity preferentially. If the remaining capacity is insufficient, the inverter will adjust active output and dynamically calculate the active and reactive best out values. In this way, the voltage of PCC is adjusted in an appropriate range to achieve the active output minimisation and reactive output optimisation of inverter. The experimental results validate the effectiveness of the proposed control scheme for voltage regulation.