Abstract: The existing blocking strategy of the 3/2-connection busbar, when a CT disconnection occurs, cannot distinguish the CT disconnection with the busbar short-circuit fault in some scenarios due to its inaccessible of the voltage information, which may cause the problem of misjudging the high-resistance short-circuit fault as a CT disconnection, or a misoperation of the bus differential protection when the heavy-load branch CT is disconnected. Therefore, on the basis of not changing the operating characteristics of the existing bus differential protection, a set of highly adaptable CT disconnection blocking strategy is proposed by making full use of the amplitude and phase characteristics of the bus differential current and the branch sequence current, avoiding the problem of the incorrect operations of the busbar protection caused by the improper CT disconnection blocking strategy. Firstly, the characteristics of the bus differential current and the branch sequence current are deduced when the bus CT is disconnection and the bus is short-circuited. and a new set of CT disconnection identification criteria is proposed by using the difference in the phase and amplitude, which realizes the identification of the CT disconnection without any voltage information, avoiding the fixed value setting caused by a single variable. In addition, the action logic between the CT disconnection and the busbar protection is optimized. In the case of a short-circuit fault, the busbar protection can be quickly started through the additional short-circuit fault identification criterion. A typical busbar model of 3/2-connection is established in the RTDS, , and a large number of simulation experiments verified the reliability of the CT disconnection identification criterion and the busbar protection blocking logic.