Research on transient synchronous stability of integrated grid-forming converters using power synchronization control

Abstract

The proportion of the integrated converters using PSC （power synchronization control） in power systems is increasing year by year， but there is a lack of in-depth research on the transient synchronization stability. Therefore， the transient synchronization stability mechanism of integrated grid-forming converters using PSC is analyzed， and measures to improve the transient stability of the converter are proposed. First， the transient stability model of the grid-forming converters with PSC during grid fault is established. Subsequently， based on the phase diagram curve （PDC） method， the destabilization mechanism of the converters and the effect of voltage coupling on the transient synchronous stability are investigated. Moreover， a control strategy to improve the transient synchronous stability by dynamically adjusting the active power command value is proposed based on the effect of voltage coupling. Finally， the electromagnetic transient simulation model of an equivalent system in a city is constructed by using PSCAD/EMTDC， which verifies the correctness of the transient stabilization mechanism of the converter-connected power system and the effectiveness of the stabilization enhancement measures under different fault conditions.

Keywords

• transient synchronization stability
• psc
• grid-forming converter
• pdc