In this paper, a linear model of power system equipped by HVDC parallel installed with HVAC is investigated. The HVDC system is mainly composed by voltage source converters (VSC-HVDC). So, there are four adjustable variables to control the power system characteristics. In this regards, one of these variables can be used as a supplementary controller input, in order to damp the oscillations efficiently. In this work the Singular Value Decomposition (SVD) method is used to realize the most effective control input of VSC-HVDC, with the aim of low frequency oscillation damping. Besides, optimum values for supplementary controller gains, are found using imperialist competition algorithm. To confirm strength of the proposed controller, the designed controller is tested in wide range of operating condition and compared with conventional scheme. The main advantage of the proposed procedure is greatly improving the dynamic response of the system. In addition, the overshoots, undershoots and the settling times are dramatically reduced by applying the proposed method. Simulation results show the good operation of proposed method so as to damp power system oscillations.Ó 2014 Production and hosting by Elsevier B.V. on behalf of Ain Shams University.