Omron RX Series - Control Gain Switching Function

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6 Vector Control
High-function General-purpose Inverter 3G3RX-V1 User’s Manual (I578-E1)
6-4 Speed Control
6
6-4-3 Control Gain Switching Function
Normally, for speed control, the inverter uses the
proportional integral (PI) control method, which controls
so that the difference between the frequency reference
and the actual rotation speed becomes 0. However, in
order to drive a single load with more than one motor,
proportional (P) control may be used. To switch to
proportional (P) control, allocate the P/PI switching
function to one of the multi-function input S1 to S8 via
the Digital Operator and turn ON the terminal. Then, set
the KPP value in the 1st P Proportional Gain (H052) to
enable proportional control.
• This function is enabled when sensorless vector control, 0-Hz sensorless vector control, or sensor
vector control is selected as the control method.
• It provides two speed control loop gain settings, which can be switched as required.
For example, switch the gain setting according to the load condition in the following cases.
Note 1 Sensorless vector control and 0-Hz sensorless vector control can be selected for the 1st/2nd control.
2 Sensor vector control can be selected for the 1st control.
6-4-3 Control Gain Switching Function
When using two control gain settings to switch between a low-level gain that does not cause vibration during
stop and a high-level gain that provides higher responsiveness for high-speed operation
When the applied load (inertia) changes to a large extent and requires the control gain to be switched
between the high-load and low-load settings
Parameter No. Function name Data Default data Unit
C001 to C008
Multi-function Input S1 to
S8 Selection
26: CAS (Control gain switching) – –
H050/H250
1st/2nd PI Proportional
Gain
0.0 to 999.9, 1000. 100.0 –
H051/H251 1st/2nd PI Integral Gain 0.0 to 999.9, 1000. 100.0 –
H052/H252
1st/2nd P Proportional
Gain
0.01 to 10.00 1.00 –
H070
For PI Proportional Gain
Switching
0.0 to 999.9, 1000. 100.0 –
H071
For PI Integral Gain
Switching
0.0 to 999.9, 1000. 100.0 –
H072
For P Proportional Gain
Switching
0.0 to 10.00 1.00 –
H073 Gain Switching Time 0. to 9999.: Gain switching taper time 100. ms
Torque
100%
0
P control
PI control
(A)
rpm
The relationship between the KPP value and speed change ratio is expressed broadly in the following formula:
(Speed change ratio) =
(KPP set value)
10
[%]
The relationship between speed change ratio and speed error is expressed broadly in the following formula:
(Speed change ratio) =
Synchronous rpm at base frequency
Speed error at rated torque [A]
× 100 [%]