(Guodian Nanjing Automation Co. Ltd., Nanjing 211100, China)

A backboard bus based design scheme for substation-area protection and control equipment used in smart substations is proposed. A multiple master communication backboard bus is designed based on multi-point low voltage differential signaling (M-LVDS). The cooperation model is described according to resource configuration and logic diagram division. With backboard bus as the core, a multi-level dataset interaction and control model is developed between the virtual logic bus, backboard bus, process bus and wide area communication network. Several topics are discussed, such as the principle of backboard, realization and function division of logic diagram, realization of multi-level data exchange. The design scheme proposed is applied in substation-area protection and control equipment for a 110 kV smart substation for function transfer, redundancy protection, concentrated backup protection, safety automatic control, etc. Site operation has proved its effectiveness and practicality.