The invention provides a current ring starting method for a
permanent magnet synchronous motor with variable PID parameters. The current ring starting method comprises the steps as follows: a three-phase winding of the motor is powered on to enable the N pole of a rotor to be stopped in the position of an A-axis direction of an ABC coordinate
system, wherein the rotor
position angle <theta> is equal to 0 at the moment; a three-phase symmetrical sine alternating
voltage is pumped to the three-phase winding of the motor, the
voltage frequency f is constantly increased, and the motor starts acceleration; the set rotor
position angle <theta> is increased progressively; after the motor is started, a position estimator begins to estimate a rotor position <theta>', and an error value <
delta> <theta> between the <theta>' and <theta> is calculated; the parameters of Kp, Ki and Kd of the current ring are adjusted through a setting module according to the
estimation error <
delta> <theta>, a motor
stator excitation component current error value <
delta>Id and a torque component current error value <delta>Iq, and after configuration is completed, the current ring is executed. By virtue of the current ring starting method, the no-position start of the
permanent magnet synchronous motor can be more reliable and
safer; and in addition, the control cost is low, and the
control system is high in dynamic performance and high in anti-interference capability.