m51971 Mitsumi Electronics, Corp., m51971 Datasheet - Page 13

• Manufacturer Part Number: m51971
• Description: Motor Speed Control
• Manufacturer: Mitsumi Electronics, Corp.

How to find rough value of motor transfer
function
(1) Finding K
Plot the relation between the motor drive current and tacho-
generator frequency to obtain the inclination.
M
Motor drive current I
K
M
a
=
I
a
=
2
I
a
f
(2) Finding
Though
this method generally takes a lot of time and labor. Measurement
of step response can find rough values easily.
Supply step-shape current to the motor in static status, measure
time
then find
M
until the motor speed reaches 63% of the final speed and
M
M
M
=
is found by measuring the motor frequency response,
MITSUBISHI <CONTROL / DRIVER IC>
M
by the following formula.
1
M
t
• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •
MOTOR SPEED CONTROL
M51971L/FP
M
63%
(18)