The invention belongs to the technical field of
AC motor transmission control, and relates to a
permanent magnet synchronous motor dead zone compensation method based on a nonlinear
flux observer. Measuring a motor induction current under a
natural coordinate system, and obtaining an alpha-beta axis current through conversion; a non-linear
flux observer in an alpha-beta coordinate
system is used as a position observation model to obtain an actual rotor position
estimation value, a rotating speed ring is formed, and sensorless control of the
permanent magnet synchronous motor is achieved; constructing a q-axis
voltage disturbance observer by measuring the phase
voltage output by the
inverter; taking the output of the q-axis
disturbance observer as the input of a
dead time calculation module to obtain a
dead time estimation value; and according to the estimated value, calculating and obtaining a dead-zone compensation
voltage, and compensating the output phase voltage of the
inverter to realize dead-zone compensation. On the basis of a non-linear
flux observer, a position-free control closed-loop structure is constructed, and instruction voltage is corrected, so that the influence of
inverter dead time on the
permanent magnet synchronous motor is reduced, and the position-free control performance is improved.