Calculation Method of DC Limit Power Considering Influence of New-generation Synchronous Condensers

Abstract

Because the new-generation synchronous condenser has strong excitation ability and leading power factor operation ability, the DC transmission power value will be effectively improved. In this paper, the reactive power limit value models of the new-generation synchronous condensers under phase-in and phase-lag operation conditions were established. Then, the correlation model between AC and DC systems considering the effects of new-generation synchronous condensers is established. Based on this, the commutation angle of DC and the parameters related to the inverter side are calculated under rated conditions. Moreover, the AC system equations is combined to solve the potential of the equivalent AC system and the power angle of DC bus voltage. Then, using DC current as an independent variable to find the maximum DC power considering the reactive power limit value of the new-generation synchronous condensers. Therefore, the initial reactive power output of new-generation synchronous condensers and the maximum power of DC transmission can be calculated.The results of this paper provide a theoretical basis for improving DC transmission power in power system analysis, and have an important role in promoting the consumption of renewable energy at the DC-fed AC grid.