Generation control system for improving design and stability of medium-voltage DC power systems on ships

Abstract

Voltage stability in medium-voltage DC (MVDC) power systems on ships is a key design goal. MVDC bus voltage stability can be impaired because of the presence of power electronic converters that can induce negative incremental resistance instabilities. This study presents a control strategy that stabilises MVDC bus voltage in the presence of destabilising constant power load converters. A state-feedback adaptive control is designed by linearisation and implemented using controlled interface converters connecting the MVAC alternators to the MVDC bus. Large signal stability of the control system is assessed using Lyapunov techniques. The proposed control is verified against both average-simplified and detailed time-domain numerical simulations, thus providing a two-way comparison.