Study on Initialization Strategy of LCC-HVDC System

The initialization of line commutated converter based high voltage DC (LCC-HVDC) system is a difficult problem in the electromagnetic transient (EMT) simulation of large-scale AC-DC system. The traditional initialization method simulates the startup process of LCC-HVDC, which is not only time-consuming, but also difficult to match with the power flow results. Firstly, this paper classified different devices and discussed the initialization strategies applicable to different devices in view of the differences between the load flow model and the electromagnetic transient model. At the same time, it is concluded that there is an error between the load flow model and the electromagnetic transient model of HVDC. Then, the load flow model of HVDC was studied, and there was an error in reactive power calcultation in the old model used frequently in PSD-BPA and PSASP. So, the load flow model of HVDC was modified to improve the accuracy of its reactive power. The effectiveness of the proposed load flow formula is verified by the LCC-HVDC in East China Power Grid.