When the traditional space vector pulse width modulation( SVPWM) is performed in the orthogonal coordinatesystem,the computational burden is more heavy and the corresponding over-modulation algorithm is morecomplex.For the purpose of facilitating the real-time operation,by analyzing the characteristics of SVPWM algorithmbased on a 60° coordinate system,this paper proposes a novel over-modulation algorithm which is easy to implementwith a small amount of computation.This algorithm can incorporate the whole modulation area of thereference voltage vector without calculating the maintain angle.In the six-step mode,this algorithm can choose thebasic voltage vector only according to the charging time of the basic voltage vector without over-modulation,whichneeds no calculation of the phase angle of the reference voltage.Theoretical analysis and experimental results showthat the proposed algorithm can save a lot of computing time.