BDU with high compatibility and low cost

A high-compatibility low-cost BDU of the present invention comprises a bottom shell and a plurality of busbars, the edge of the top surface of the bottom shell is provided with a plurality of high-voltage port fixing positions, the plurality of busbars are detachably installed on the bottom shell, and high-voltage ports of the busbars are detachably installed on the high-voltage port fixing positions. And at least one high-voltage port fixing position is reserved for standby application. According to the invention, the plurality of high-voltage port fixing positions are arranged on the bottom shell of the BDU, at least one high-voltage port fixing position is reserved for standby application, and the positions of the high-voltage ports are changed by matching different busbars for installation, so that flexible electrical layout is realized, the compatibility of BDU products is improved, and the reliability of the BDU products is improved. Multiple electrical layout schemes can be realized by using one bottom