Mitsubishi FR-A800

(G) Control parameters
PARAMETERS
629
5
GROUP
G
NOTE
• Setting of the droop gains should be approximately the rated slip of the motor.
Limiting the frequency after the droop compensation (0 limit)
• By setting Pr.288 at the time of Real sensorless vector control, vector control, or PM sensorless control, the negative
frequency command when the frequency after droop compensation can be limited.
 During Advanced magnetic flux vector control, the action same as the "0" setting will be performed.
Droop control break point setting (Pr.994, Pr.995)
• By setting Pr.994 and Pr.995, break point (1 point) can be set up for the droop compensation frequency. Setting a break
point allows the inverter to raise the droop compensation frequency for light-load (no load) operation without raising it for
heavy-load operation.
NOTE
• Droop break point function is disabled in one of following conditions. (Linear compensation by Pr.286 will be performed.)
Pr.995 = "100% (initial value)"
Pr.286 <Pr.994
Pr.994
 Pr.995  Pr.286 / 100%
Parameters referred to
Pr.1 Maximum frequency page 345
When Pr.288 = "0 to 2" or Advanced magnetic flux control
Droop compensation frequency =
Current for torque after filtering

Rated motor frequency  droop gain
Rated torque current 100
When Pr.288 = "10, 11"
Droop compensation frequency =
Current for torque after filtering

Motor speed  droop gain
Rated torque current 100
Rated slip =
Synchronized speed at the time of base frequency - rated rotation speed
 100[%]
Synchronized speed at the time of base frequency
Pr.288
Setting
Operation
When the droop compensation frequency
is negative
Droop compensation
reference
0
(initial value)
Without droop control during
acceleration/deceleration
Limit with 0 Hz
(Limit with 0.5 Hz under Advanced magnetic flux
vector control)
Rated motor frequency
10
 Motor speed
1

Constantly droop control during
operation
Rated motor frequency
11
 Motor speed
2

Constantly droop control during
operation
Do not limit (reverse)
(At the time of vector control, PM sensorless vector
control)
Rated motor frequency
Limit with 0 Hz
(At the time of Real sensorless vector control)
Droop break point gain
(Pr.994)
Droop compensation
frequency
Increased amount of the
droop compensation
frequency
Droop break point torque
(Pr.995)
Torque
100%
Droop gain
(Pr.286)
-100%
Frequency
0
Rated
frequency