A comparison between synergetic control and feedback linearization for stabilizing MVDC microgrids with constant power load

This paper investigates the use of synergetic control for voltage stability of a DC microgrid where the loads are interfaced through power electronic converters fed from a DC power source. When tightly regulated, these loads exhibit a constant power load (CPL) behavior. CPLs have negative incremental impedance behavior which may lead to system instability. The synergetic control approach is compared with a linearizing feedback approach, which was investigated by the authors before and therefore serves as a reference case. Both of the selected approach achieve stability at large signal level and overcome hereby the limits of existing small signal approaches. Both of the selected control techniques act on the interface converters at the generator side and leave the load side converters untouched. The real time performance of the system and their controllers is observed on a MVDC microgrid which is implemented in Opal-RT.