Second‐order lead compensator‐based quadrature PLL for sensorless interior permanent magnet synchronous motor control

Abstract

To eliminate harmonic components in estimated speed and position information generated by inverter non-linearities for the interior permanent-magnet synchronous motor (IPMSM) sensorless control, a second-order lead compensator-based quadrature phase-locked loop (SOLC-Q-PLL) is proposed for the sliding mode observer. An adaptive super-twisting sliding mode observer is taken to estimate back electromotive forces (EMFs) for IPMSM. Harmonic components in estimated position information generated by inverter non-linearities are analysed. Being dependent on the corresponding analysis, the SOLC-Q-PLL is proposed to eliminate sixth position estimation errors only by introducing a second-order lead compensator without causing phase delay for the phase-locked loop system. The introduction of the second-order lead compensator does not influence the bandwidth of the phase-locked loop system so that a fast transient response can be achieved, and this algorithm is easy to implement digitally due to its simple structure. Eventually, a series of experiments are conducted to validate the capability of the proposed algorithm.