The main factors for planning DC links terminating at AC system locations from the point of interactions between AC and DC systems are illustrated， such as the effective short-circuit ratio（ESCR）， the voltage static indicator（VSI）， the power losses of the termination system， etc. A new method is proposed to select stable and economical AC buses as the locations of DC links. Based on the linear weighted summation method for multi-objective decision-making problems， the objective function is established to select the optimal placement of a commutation bus by setting the threshold values of all indices， normalizing them and using a combinatorial assigning method to rationally determine the weight coefficients. According to the objective function value of each node， the optimal one will be chosen as the commutation bus. Numerical tests show that， with stability and economy considered at once， the method presented is effective and feasible.