[Objective] In medium- and high-speed domain sensorless control drive systems of permanent magnet synchronous motor (PMSM)

the traditional linear extended state observer (LESO) suffers from observation delays in back electromotive force estimation due to bandwidth limitations

which leads to significant errors in rotor position and speed estimation. Aiming at this problem

a PMSM sensorless control strategy based on phase lead correction LESO (PLC-LESO) is proposed. [Methods] Firstly

the design method of the traditional LESO-based sensorless control scheme was introduced

and its inherent observation delay problem in back electromotive force estimation was systematically analyzed using frequency domain analysis. Then

a phase lead correction unit was introduced and the PLC-LESO was designed to observe the back electromotive force. Finally

in order to verify the feasibility and effectiveness of the proposed control strategy

a simulation model was built based on Matlab/Simulink

and the rotor position and speed information was estimated using normalized phase-locked loop to compare and analyze the observation results of the traditional LESO and PLC-LESO. [Results] The simulation results showed that

under identical observer bandwidth setting

the rotor position estimation error of the traditional LESO was 0.6 rad

while the PLC-LESO was able to accurately track the back electromotive force with a rotor position estimation error of only 0.005 rad. When the bandwidth of the traditional LESO was increased to 30 000

its back electromotive force tracking performance was improved

but the fluctuation of the rotational speed estimation was intensified

resulting in resulting in poor system stability. Whereas

the PLC-LESO not only tracked the reverse potential accurately without increasing bandwidth

but also controlled the speed fluctuation within ±10 rpm. [Conclusion] Compared with the traditional LESO

the proposed PLC-LESO exhibits superior control performance in the estimation of the back electromotive force tracking

which improves the accuracy of the system in estimating the rotor position and speed information.