The aim of the paper is to introduce an independentsupervisory architecture for optimal control of power flow inHVDC grids. Such an independent DC supervisory control isable to manage the optimal operation of connecting VSCs incooperation with other AC SCADA systems. Identifying the gridtopology, DC supervisory control employs an optimal power flow(OPF) calculator based on interior point optimization method todetermine the setpoint values for all HVDC stations in a grid.The performance of such an independent supervisory control hasbeen studied through various test case scenarios using a real-timeco-simulation platform.