how to rectify overshoot

I am wotking on a cocept of 'Transient stability of a two-machine transmission system with Power System Stabilizers (PSS) and Static Var Compensator (SVC)'which s taken from matlab simulink demo. Here i want to calclate speed deviation as given in paper figure num Fig.9(f) http://www.ijetae.com/files/Volume2Issue7/IJETAE_0712_41.pdf

tha graph starts from zero,were I tried subtracting the speed with reference value of 1,but the graph increaase not in steady state ,kindly help

I have attched the simulink model