Speed Control (P/Pi) Switching Function - Hitachi SJ-FB Instruction

7.4 Speed control (P/PI) switching function

Speed control mode
proportional-integration compensation (Pi), which keeps the
deviation between the actual speed and speed command
becomes 0. Further, you can also achieve a propotional control
function, which can be used as drooping operation (i.e. one load
with several inverters) with this option card.
Set P/PI switching function to one of the intelligent input terminal 1∼8 by the operator to achieve
this function. (Input '43' in one of C001∼C008.) When this is turned on, control mode becomes
proportion control (P).
Please set proportional gain(Kpp ; a value used to decide the speed change rate) to H052 by a
digital operator. The relationship between the Kpp value and the speed change rate is shown
below.
Relationship between Kpp Value and Speed Change Rate
( Speed
Relationship between Speed Change Rate and Rated Rotation Speed
is normally
( Speed Change Rate
Torque P control
100 %
0
Figure 7-6 Torque characteristic (P/PI)
Change Rate ) =
Synchronou
Chapter 7
controlled by
10
) =
( Kpp Set Value
PI control
(A)
Rotation Speed
Speed Error at Rated
s speed base
31
FUNCTIONS
Relation
st
A044: 1 Control Method
st
P052: 1 Proportional gain
(%)
)
( )
Torque A
frequency