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The three-phase/switch Y-type two-level rectifier is widely used in the unidirectional powerflowing applications such as LED illumination, communication and uninterruptible power supply. This paper presents the working principle of three-phase/switch Y-type two-level rectifier, and proposes two simple and fast modulation techniques (12-sector SVPWM and simplified equivalent SVPWM) based on the virtual vectors. The reference vectors of the 12-sector SVPWM are synthesized by utilizing real basic vectors and virtual vectors linearly combined from these real vectors in a switching period. So the created virtual vectors can reduce the error of reference voltage synthesis, contributing to better input current performance, this paper proposes a simplified 12-sector equivalent SVPWM, and shows the novel threephase modulation wave expressions and waveforms. The proposed simplified 12-sector equivalent SVPWM does not need the process of sector determination with reducing computational processing time which is attractive for digital implementation. Finally, performance of the proposed modulation methods for a Y-type two-level rectifier using a 5kW prototype is experimentally verified.