<p>Active sound generation technology can effectively improve the interior sound quality of electric vehicles (EVs). Traditional active sound generation methods generally simulate the internal combustion engine (ICE) sounds under a single driving condition, which cannot meet the increasingly prominent demand for diverse interior acoustic experiences under multiple driving conditions. To address this issue, a novel active sound design method and sound generation strategy are proposed based on the concept of musical motive. A hierarchical design method is proposed to construct distinct yet harmonious musical motives corresponding to multiple driving conditions. To resolve the challenge of abrupt sound changes during synthesis, a quadratic curve cross-fade method incorporating initial and terminal proportional coefficients is proposed. Meanwhile, a synthesis quality index (SQI) is established to evaluate the synthesis effect. A multi-driving-condition sound generation control strategy and associated control methods accounting for the masking effect are developed, with their effectiveness verified via a rapid control prototyping (RCP) system. Finally, a multi-dimensional comparative analysis with existing active sounds is conducted, and results indicate that the musical motive-based active sound achieves a 57% improvement in sound quality relative to the original vehicle background noise. Furthermore, preference differences across cultural regions and genders reveal that musical motive-based active sound and ICE-based sound each exhibit distinct advantages. These findings highlight the application potential of the proposed method in facilitating the development of intelligent, user-centric acoustic cockpits for future EVs.</p>