To provide a motor controller capable of suppressing an excess current resulting from a back electromotive force.
The motor controller includes a decision means S101 deciding the positive or negative decision value subtracting a back electromotive-voltage estimate from a command voltage value. The motor controller further includes switching-element control means S103, S104, S106 and S107 turning a first switching element on, duty-controlling a second switching element, turning a third switching element off and duty-controlling a fourth switching element so as to be inverted to the second switching element so that the applying direction of a power-supply voltage to a driving motor is directed in the forward-rotational direction when the decision value is positive and duty-controlling the first switching element, turning the second switching element on, duty-controlling the third switching element so as to be inverted to the first switching element and turning the fourth switching element off so that the applying direction of the power-supply voltage to the driving motor is directed in the reverse-rotational direction when the decision value is negative.
NAKAMURA HIDEO
TAZOE KAZUHIKO
Masahiro Fujii
Yasunari Mita
Masaaki Iida