Aimed at the problems of a large number of switching devices and complex control strategy for an inverter in the multi-motor drive system of a 800 V high-voltage platform for electric vehicles, a fifteen-switch three-level dual-output inverter is proposed, which simplifies the inverter topology and reduces its cost by device multiplexing. First, a detailed analysis of the proposed inverter topology and working principle is performed, its structural characteristics are summarized, and the effective switching state and maximum voltage stress analysis are given, providing a theoretical basis for the selection of switching devices and system design. Then, a single-leg independent model prediction current control strategy is put forward, and a prediction model of single-leg dual-output port current is established, which effectively reduces the prediction operation under the premise of realizing three-leg independent prediction control and single-leg dual-output current integrated optimal control. Finally, the correctness and effectiveness of the proposed inverter and its control strategy were experimentally verified based on a Typhoon HIL 402 platform.