Hybrid Multi-Infeed Interaction Factor Calculation Method Considering Voltage Regulation Control Characteristics of Voltage Source Converter

Abstract

Voltage source converter based high voltage direct current (VSC-HVDC) can participate in voltage regulation by flexible control to help maintain the voltage stability of the power grid. In order to quantitatively evaluate its influence on the voltage interaction between VSC-HVDC and line commutated converter based high voltage direct current (LCC-HVDC), this paper proposes a hybrid multi-infeed interaction factor (HMIIF) calculation method considering the voltage regulation control characteristics of VSC-HVDC. Firstly, for a hybrid multi-infeed high voltage direct current system, an additional equivalent operating admittance matrix is constructed to characterize HVDC equipment characteristics under small disturbance. Secondly, based on the characteristic curve between the reactive power and the voltage of a certain VSC-HVDC project, the additional equivalent operating admittance of VSC-HVDC is derived. The additional equivalent operating admittance matrix calculation method is proposed. Thirdly, the equivalent bus impedance matrix is obtained by modifying the alternating current (AC) system admittance matrix with the additional equivalent operating admittance matrix. On this basis, the HMIIF calculation method based on the equivalent bus impedance ratio is proposed. Finally, the effectiveness of the proposed method is verified in a hybrid dual-infeed high voltage direct current system constructed in Power Systems Computer Aided Design (PSCAD), and the influence of voltage regulation control on HMIIF is analyzed. KEYWORDSHybrid multi-infeed high voltage direct current system; hybrid multi-infeed interaction factor; control modes; equivalent node impedance ratio; voltage interaction characteristics