ROTATION DETECTION DEVICE

摘要

Torque ripple of a motor due to a rotation detection device is reduced. A periodicity gain multiplier 51 multiplies the rotation angle ¸ of a detection target by a ripple periodic number m per rotation of the detection target. An adder 53 adds a phase adjusting value "È" from a phase adjustor 49 to the value "m¸". The value "sin(m¸ + È)", which is calculated by a sine calculator 55, is multiplied by a predetermined gain G by an amplitude adjustor 57 and by the angular velocity É of the detection target by a multiplier 59. A subtractor 61 subtracts the output of the multiplier 59 from the value "É" and outputs "É(1 - Gsin(m¸ + È))". The output of the subtractor 61 and the output "m¸ + È" of the adder 53 are input to the phase adjustor 49 and amplitude adjustor 57. The phase adjustor 49 calculates the phase adjusting value "È" based on the summation of the derivative values of the outputs from the subtractor 61sampled for each "À/2" of the output from the adder 53. The amplitude adjustor 57 calculates the gain G based on the summation of the differences between averages of the sampled values at "0" and "À" of the output of the adder 53 and averages of the time integration value at the integral interval of "0" to "À".