As the amount of wind and solar renewable energy connected to the power grid gradually increases, large-scale wind farms and photovoltaic (PV) stations begin to participate in secondary frequency control for an interconnected power grid. In this situation, an optimal coordinated control of multi-source for secondary frequency control with wind and solar renewable energy is constructed, which can distribute the real-time total power to various regulation resources. To handle this complex nonlinear optimization, a simple pattern search is used to rapidly obtain a high-quality dispatch scheme under different power disturbances. Thus the dynamic response regulation performance of the control area can be improved. Lastly, an extended IEEE two-area control model is designed to evaluate the performance of the proposed technique and it is compared with the engineering dispatch method and intelligent optimization algorithms. This work is supported by National Natural Science Foundation of China (No. 61963020 and No. 51907112) and Yunnan Power Grid Stability Control Technology Research and Closed Loop Simulation Platform with Multiple DC and High Proportion of New Energy (No. 056200KK52190009).