Accounting for electroplating, metallurgy, electric vehicles and other industries, the proportion of DC load in the grid is growing. The influence on the frequency stability of the power grid is more apparent. To respond to the demand of power system frequency regulation, this paper proposes that the droop control of DC load voltage can be realized through the power electronic interface circuit under the precondition of ensuring the power quality of the power grid so that the adjustable DC load can respond to the abnormal event of power grid frequency. In addition, in order to ensure the normal work of DC load and avoid switching the control of DC load frequently, this paper further proposes the control mode of divisional frequency regulation to meet the demand of power grid, such as demand side response and power grid friendly. The control method proposed in this paper has a simple structure and is easy to implement, which can reduce the impact of DC load connection on the power grid and improve the adaptability of the power grid to large-scale DC load access. At last, using simulink model verifies the feasibility and effectiveness of this scheme.