CONTROLLER OF INDUCTION MOTOR

PROBLEM TO BE SOLVED: To identify a slip frequency of an induction motor with high accuracy.SOLUTION: A controller comprises: a d-axis voltage command-generating part 10 which generates a q-axis voltage command vq** as a q-axis secondary magnetic flux command φ2q*=0 with a primary inductance identification value xd^; and a slip angular frequency command-generating part 11 which identifies a reverse secondary time constant W2 so that a deviation between the q-axis voltage command vq** and a q-axis voltage command vq* becomes 0 (the q-axis secondary magnetic flux φ2q becomes 0) and calculates a slip angular frequency command ωs*. In this way, the controller is arranged so that the primary inductance identification value xd^ which is high in identification accuracy is used to control a q-axis secondary magnetic flux φ2q=0. Therefore, the identification accuracy of a reverse secondary time constant identification value W2^ is raised, and a slip frequency can be identified with high accuracy.SELECTED DRAWING: Figure 2 【課題】誘導電動機のすべり周波数を精度高く同定する。【解決手段】ｄ軸電圧指令生成部１０は、ｑ軸２次磁束指令φ２ｑ＊＝０として、１次インダクタンス同定値ｘｄ＾を用いたｑ軸電圧指令ｖｑ＊＊を生成する。スリップ角周波数指令生成部１１は、ｑ軸電圧指令ｖｑ＊＊とｑ軸電圧指令ｖｑ＊との間の偏差が０になるように（ｑ軸２次磁束φ２ｑが０になるように）、逆２次時定数Ｗ２を同定し、スリップ角周波数指令ωｓ＊を算出する。これにより、同定精度が高い１次インダクタンス同定値ｘｄ＾を用いて、ｑ軸２次磁束φ２ｑ＝０の制御を行うようにしたから、逆２次時定数同定値Ｗ２＾の同定精度が高くなり、すべり周波数を精度高く同定することができる。【選択図】図２