His specific areas of research cover frequency load-shedding, static and dynamic voltage stability, PMU based topology estimation, power system stabilizer design, power system bifurcation and maximum loadability investigations. Other areas include modelling power systems for fault analysis, in particular open-phase faults and the problems of accurately determining the zero sequence impedances in this context. In addition, Dr. Karrar has work on distribution systems with particular reference to ferroresonance and has developed recent interest in microgrid islanding.