Initial Rotor Position Detection of Surface Mounted Permanent Magnet Synchronous Motor

A new method for initial rotor position detection of surface-mounted permanent magnet synchronous motor（SPMSM） without any rotational transducer is presented.The method can effectively improve the shortcomings of traditional methods in execution time and implementation complexity.It is realized in two steps.Firstly a high-frequency sinusoidal voltage signal is injected into the estimated synchronous rotating coordinate system,thus the first estimated value of rotor position can be estimated through closed-loop adjustment.Then pole polarity is determined using different time constant characteristics of d-axis equivalent circuit under different poles.Combined with the estimated value,the correct initial position can be obtained.Experimental verification of arbitrary initial rotor angle is carried out on dSPACE real-time simulation system.The results show that the proposed method can realize fast and accurate initial position detection of SPMSM.