Harmonic Injection-Based Torque Ripple Reduction of PMSM With Improved DC-Link Voltage Utilization
Lijian Wu, Zekai Lyu
Abstract
This letter proposes an improved scheme for torque ripple reduction of permanent-magnet synchronous machines (PMSMs) considering dc-link voltage utilization. Different from the previous methods, both <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">q</i> -axis and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</i> -axis harmonic currents are optimized and injected. Specifically, the appropriate <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">q</i> -axis harmonic current reference is obtained through harmonic analysis of PMSM. Furthermore, the harmonic voltage control loop is included to generate the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</i> -axis harmonic current reference, which can ensure that the magnitude of the voltage vector satisfies the maximum output voltage circle under the voltage constraint. The virtual signal and multiple reference frame-based proportional-integral controllers are employed to regulate the harmonic components. The effectiveness of the proposed method is validated by experimental results.