Permanent magnet synchronous motor (PMSM) drive systems that utilize small-capacity film capacitors in DC bus instead of electrolytic capacitors have advantages such as long lifespan, compact size, and low cost. However, when traditional dual-mode overmodulation strategies are employed to enhance DC bus voltage utilization, significant fluctuations in the voltage modulation index can cause the output voltage vector to frequently enter and exit the square-wave modulation state. This results in substantial distortion of the output voltage. On the other hand, conventional single-mode overmodulation strategies, although producing less output voltage distortion, are unable to achieve the square-wave modulation state, leading to limited output voltage capability. To balance output voltage capability and distortion, this paper investigates a hybrid single-dual mode overmodulation strategy for electrolytic capacitorless PMSMs. By incorporating a hybrid judgment step after the condition that determines whether the PMSM enters square-wave modulation in the traditional dual-mode overmodulation strategy, the allocation ratio of conventional single and dual-mode overmodulation strategies within the sectors is adjusted, thereby improving the control performance of PMSM drives in the overmodulation region. Simulation results validate the effectiveness of the proposed method.