An improved sensorless control strategy for IPMSM using based on high-frequency signal injection

This paper proposes an improved sensorless control strategy for Interior Permanent Magnet Synchronous Motors based upon the injection of high-frequency rotating sinusoidal voltages. Derived from the traditional injection method, the strategy addresses key issues such as slow convergence, filter-induced errors and signal distortion arising from filter dependence by developing a targeted optimization scheme that omits the low-pass filter module and replaces the high-pass filter with a Second-Order Generalized Integrator (SOGI) and accurate extraction of high-frequency currents is achieved. This improvement fundamentally eliminates filter-induced delays and error accumulation, reduces algorithm complexity, and enhances the system's dynamic response, control precision and operational stability. Simulation tests validate the correctness.