Motor position estimation method, motor position estimation apparatus, inverter control method, and inverter control apparatus

摘要

PPROBLEM TO BE SOLVED: To provide a technique for switching a position estimating technology suitable in low speed rotation zone and a position estimating technique suitable in high speed rotation zone without causing an abrupt variation in the estimate of position. PSOLUTION: When the rotational speed increases and a rotational speed estimate ^SBre/SBtransits from a value lower than a predetermined threshold C to a value exceeding the threshold C (S102), a switching means 13 judges whether a position candidates ^SBHI/SBand ^SBLOW/SBare equal to each other or not (S103). If the position candidate ^SBHI/SBis larger/lower than the position candidate ^SBLOW/SB, q-axis inductance Lq is increased/decreased (S104, S105, S106) and the position candidate ^SBLOW/SBis employed as a position estimate ^SBre/SB(S107). When they become equal to each other, the position estimate ^SBre/SBis invariant even if the estimation method is switched and the position candidate ^SBHI/SBis employed as the position estimate ^SBre/SB(S108). PCOPYRIGHT: (C)2006,JPO&NCIPI