A different objective function (OF) and model of reactive power optimization is proposed in this paper. In the model, the values of compensator are regarded as the controllable variables to be evaluated and the objective is to minimize the voltage deviation. An efficient algorithm for approximation of initial problem is described. The proposed method overcomes the drawbacks of conventional reactive power optimization method. Compared with that obtained using a traditional optimization method, Simulation has been applied to practical IEEE 30-bus system. The test results show that this method is feasible and practical method.