The steady stability limit of a particular circuit of a power systems is defined as the maximum power the can be transmitted to the receiving end without any loss of synchromism. The study of steady state stability is basically concerned with the determination of upper limit of machine loading before losing synchronism, provided the loading is increased gradually.
The steady state stability is the stability of the system under conditions of gradual to be relatively slow change in load the load is amused to be applied at a rate which is slow when compared either with the natural frequency of oscillations of the major parts of the system.
In steady state stability the power system attains its stability after a slight unbalance. In dynamic stability external device required to regain the stability.