Hitachi SJ-FB - Manual (Page 31)

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Chapter 7 FUNCTIONS
A044: 1 st Control Method
P052: 1 st Proportional gain
7.4 Speed control (P/PI) switching function Relation
Speed control mode is normally controlled by
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.
(%)
) Value Set Kpp (
10
= ) Rate Change Speed (
Relationship between Kpp Value and Speed Change Rate
0 Rotation Speed
Torque
100 %
PI control P control
(A)
Figure 7-6 Torque characteristic (P/PI)
( )
frequency base speed s Synchronou
A Torque Rated at Error Speed
= ) Rate Change Speed (
Relationship between Speed Change Rate and Rated Rotation Speed