Hitachi SJ-FB manual Speed control P/PI switching function, Torque characteristic P/PI

P052: 1st Proportional gain

A044: 1st Control Method

Relation

Chapter 7 FUNCTIONS

7.4 Speed control (P/PI) switching function

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.

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(Speed Change Rate) = (Kpp Set Value) (%)

Relationship between Kpp Value and Speed Change Rate

Torque P control PI control

100 %

(A)

0 Rotation Speed

Figure 7-6 Torque characteristic (P/PI)

Speed Error at Rated Torque (A)

(Speed Change Rate) = Synchronous speed base frequency

Relationship between Speed Change Rate and Rated Rotation Speed

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