The controller was designed for multimachine power system. The mechanical power supplied to each machine has random disturbances such as floating engine speed. The first generator is the reference to which the rest of the generators are tuned. The quadratic criterion of control quality, depending on the difference in the angles of the generator shafts and the control value, has been optimized. The control linearly depends on the state of the dynamic system. The problem is solved using the stochastic maximum principle on an infinite time interval that allows us to synchronize shafts for as long as we like. Simulation of transient processes at different levels of noise has been carried out.