Sensorless Control of IPMSM Equipped With LC Sinusoidal Filter Based on Full-Order Sliding Mode Observer and Feedforward QPLL

A position sensorless control of interior permanent synchronous motor (IPMSM) equipped with LC sinusoidal filter based on the full-order sliding mode observer (FOSMO) and feedforward quadrature phase-locked loop (FQPLL) is proposed in this article. The FOSMO is designed to estimate stator currents, stator voltages, and extended back electromotive forces of IPMSM. To enhance the rapidity of the convergence and accuracy of the estimation of the FOSMO, an adaptive gain matrix is designed by adopting equivalent control theory and Lyapunov stability theory. In order to suppress the dc deviation in the position estimation error under acceleration or deceleration operations, a robust and anti-interference feedforward loop without differentiator and motor parameters is added to the conventional quadrature phase-locked loop. The parameter design method of the proposed FQPLL is studied by analysis of the frequency characteristics. The experimental results verify the effectiveness of the proposed strategy.