To improve the safety and reliability of provincial power grid dispatching, it is of significance to build a dual active dispatching system with parallel operation and one key switching. Based on complex parallel control theory and combined with the application requirements of the dual active dispatching system of a provincial power grid, this paper puts forward the architecture of a dual active dispatching system with the characteristics of a parallel system. It also systematically studies the basic functions and implementation methods of important components in the system, such as management and control, experiment and evaluation, learning and training, parallel execution and feedback. The construction of a double active dispatching system of the provincial power grid is completed. The scheme solves the core problems such as synchronization, consistency verification and dual active switching between the two systems, and improves the operational stability and switching efficiency of the dual active scheduling system. This work is supported by the National Major Project (No. 2018YFB0904800) and Strategic International Science and Technology Innovation Cooperation Key Project of National Key Research & Development Program (No. 2020YFE0200400).