Method for correcting compensation item of permanent magnet synchronous motor (pmsm)

A method for correcting a compensation item of a PMSM motor, the method comprising:

• offline measuring an error data of a parameter of a PMSM motor in a control process;
• providing a series of current commands and calculating compensation values of the parameter corresponding to the series of current commands, and establishing a lookup table with regard to the series of current commands and the compensation values of the parameter corresponding to the series of current commands;
• storing the lookup table in a memory of a motor controller;
• starting and allowing the motor to work at a normal state;
• and
• online correcting the error data of the parameter by using the lookup table;
• wherein:
• the parameter of the PMSM motor refers to a deadzone error of a frequency inverter, and the lookup table refers to a relationship between the series of current commands and deadzone compensation values;
• and
• establishing the lookup table with regard to the series of current commands and the compensation values of the parameter corresponding to the series of current commands comprises:
• 1) controlling the frequency inverter to power on one phase of coil windings of the motor, and power off the remaining phases of coil windings, stepwise increasing the current of the one phase of coil windings from 0 to a rated current;
• and
• 2) recording and measuring a command voltage and a current generated by the command voltage when stepwise increasing the current, comparing the command voltage with a product of a stator resistance and the current generated by the command voltage, to acquire a voltage error, dividing the voltage error by a DC bus voltage, to obtain a deadzone compensation value corresponding to the current generated by the command voltage, and combining currents generated by different command voltages with corresponding deadzone compensation values, to form the lookup table involving the deadzone compensation values.