Voltage stability analysis of power systems with a large number of non-synchronous machine sources connected

Abstract

Compared with synchronous generators, the steady-state and dynamic characteristics of non-synchronous machine sources represented by line commutated converters (LCC) and voltage source converters (VSC) are quite different. The voltage stability of power systems will be changed when a large number of non-synchronous machine sources (NSMS) are connected. The voltage stability of power systems with NSMSs connected is analyzed in this paper. Firstly, based on the relationship between the Jacobian matrix singularity and the small disturbance voltage stability (SDVS), the impact of NSMSs on the SDVS of active systems is analyzed. Secondly, whether there is a reasonable voltage solution in the transient process is taken as a large-disturbance voltage stability (LDVS) criterion, the impact of NSMSs on the LDVS of active systems is studied. Thirdly, for a special scenario where the VSC supplies power to a passive system, the requirements of the voltage stability on load types and VSC parameters are discussed. Finally, based on the Power System Simulator/Engineering (PSS/E), simulations are carried out in the Shanghai power system and a passive power system, and the theoretical analysis results are verified.