Research on Anti-DC Bias and High-Order Harmonics of a Fifth-Order Flux Observer for IPMSM Sensorless Drive
Yanping Zhang, Zhonggang Yin, Fengtao Gao, Jing Liu
Abstract
Due to various nonideal factors, including the motor parameter mismatches, detection errors, converter nonlinearities, noise, etc., dc bias and high-order harmonics exist in the flux model, which make the traditional flux observer estimation inaccurate. In order to suppress dc bias and high-order harmonics, an interior permanent magnet synchronous motors (IPMSM) sensorless drive method based on a fifth-order flux observer (FOFO) is proposed in this article. The proposed FOFO can completely remove dc bias and has a strong filtering ability for high-order harmonics. Additionally, the parameters of the FOFO are set through the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</i> -domain analysis. Then, the discrete FOFO is obtained for better implementation in digital systems. The proposed FOFO is verified by experiments on a 2.0-kW IPMSM drive platform.