Online q-axis inductance and resistance identification of IPM synchronous motor based on relationship between its parameter mismatch and current

This paper proposes a new approach to achieve on-line identification of the q-axis inductance and the resistance of the interior permanent magnet synchronous motor (IPMSM) on the basis of the relationship between the mismatch of Lq and the d-axis feedback current. The value of the d-axis feedback current depends on the mismatch of Lq, and the consecutive samplings of the d-axis feedback current make it possible to calculate the true value of Lq. After Lq is identified, R can also be identified by using the same identification system. The proposed identification technique is examined through some computer simulations and experimental tests. No sensitivity to the winding resistance variation is also checked through the tests. The test results demonstrate the fast convergence of the identified value to the true one with a small error.