Abstract:

In this paper, the mechanism of the enhancement of transient stability of multi-machine systems by the emergency DC power support （EDCPS） is analyzed. Then, with a timely EDCPS, an appropriate DC power rise and the corresponding rising rate in the first two up-swing courses, and with a suitable drop and the corresponding dropping rate in the first two back-swing courses, the transient stability is well improved. Moreover, by using the genetic/taboo searching algorithm, the modulation parameters are well optimized. Thus, according to the pre-set key power flow or the real-time power flow as well as the preconceive accident sets in the energy management system, the transient stability parameters of some serious preconceive accident sets can be calculated off line or on line in a certain operation mode. Case study indicates that the proposed EDCPS strategy effectively improves the transient stability of the power system.

Key words: AC/DC hybrid system, emergency DC power support, angle stability, voltage stability, optimization control