The Voltage Regulation Control Strategy with Distributed Photovoltaic Participation under Serious Failure Based on Transient Voltage Margin

With the poor ability of distributed PV to withstand voltage fluctuation, the voltage fluctuation caused by DC blocking can lead to large-scale disorderly de-networking of distributed PV, especially those distributed PV which close to voltage weak buses. which means that more and more attentions are paid to the transient voltage stability (TVS). If distributed PV can participation in reactive compensation, we don’t need to add additional reactive power compensator, voltage stability of voltage weak buses will be increased, which can reduce PV off-grid. Therefore, for the HVDC receiving end system under distributed PV intensive access, first of all, we need to find the voltage weak bus, then increase the reactive power output of distributed PV near the voltage weak buses to increase transient voltage margin. Taking the simplified model of power system in Anhui Province as an example, the validity of the strategy is verified, and the results show that the transient voltage stability of the system has been improved.