Technique for correcting resolver offset

摘要

Disclosed is a technique of correcting a resolver offset by measuring and correcting an offset of a resolver assembled to a motor of an eco-friendly vehicle in an accurate and simple way. The offset measurement process includes, after completing the assembly of a resolver a resolver to a motor, rotating the motor by using a rotation device able to transfer a rotation force to the motor, setting a voltage instruction and current-controlling the motor according to the voltage instruction, and obtaining a d-axis current and a q-axis current, which are feedback currents, during the current-control of the motor. Then when the system is in a steady state, a resolver offset ({tilde over (θ)}) is calculated from the d-axis current and the q-axis current by using {tilde over (θ)}=tan−1(d-axis current/q-axis current).

主权项

1. A method of correcting a resolver offset comprising an offset measurement process,
wherein the offset measurement process comprises:
after completing the assembly of a resolver to a motor, rotating the motor by using a rotation device capable of transferring a rotation force to the motor;setting, by the controller, a voltage instruction and current-controlling the motor according to the voltage instruction;obtaining, by a controller, a d-axis current and a q-axis current, which are feedback currents, during the current-control of the motor;determining, by the controller, when a state is a steady state in which the d-axis current and the q-axis current are constant within a set range; andwhen it is determined that the state is the normal state, calculating, by the controller, a resolver offset ({tilde over (θ)})from the d-axis current and the q-axis current by using {tilde over (θ)}=tan−(d-axis current/q-axis current),wherein after the d-axis current and the q-axis current are obtained in a state where the motor is rotated by a rotation device, the voltage instruction is calculated from the obtained d-axis current and q-axis current based on the following equations:
Vd=−ω(L1+L2)iq−Kid Vq=ω(L1+L2)id−Kiq  (E1),wherein Vd represents a d-axis voltage instruction, Vq represents a q-axis voltage instruction, ω represents a motor rotator angular velocity, L1 and L2 represent inductance constants, id represents a d-axis current, iq represents a q-axis current, and K represents a control constant.