This paper proposes the synchronous PWM whose number of the sampling per sector is one for high speed drive system. A synchronous PWM has already been introduced in high power-low switching system to reduce the harmonic frequency components of the modulated voltage. However, some methods are only implemented in an open loop V/F control and other methods need a complicated structure for the closed loop control. In this paper, three different types of the single vector modulation per sector are considered for a high speed drive system. One is the boundary sampling synchronized at 0º. The other strategies are the center sampling synchronized at 30º with the continuous PWM and discontinuous PWM. Without any an over modulation algorithm, the magnitude of the phase voltage can be from zero to the maximum value in 2 level inverter. Three modulation strategies can be implemented in the closed loop control and the simulation results are shown.