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7.3Velocity control using armature voltage feedback
The reference signal should be connected to the differential input and R3,R4 should be calculated and inserted according to:
R3 = R4 = 1.33xVdm | (Kohm) |
Vdm - maximum reference | voltage at the differential input. |
The armature voltage feedback will enter the error amplifier by inserting R8, calculated for the two voltage types as follows:
For ISP-X/65:
R8(65V) = 1.3xVam | (Kohm) |
Vam - armature voltage at maximum application speed
For ISP-X/135:
R8(135V) = 0.73xVam(Kohm)
Vam - armature voltage at maximum application speed
IxR compensation
In order to improve the speed stability in various load conditions, an IxR compensation is required. This is achieved by:
-Connect the Current Feedback Monitor (terminal
-Rotate T7 to max. CCW position (minimum IxR compensation).
-Insert R1 as follows:
3 x | Vam |
R1 = | (Kohm) |
Rm | x Ip |
Vam - Armature voltage at maximum application speed.
Ip - Amplifiers' rated peak current limit.
Rm - Total ohmic resistance of motor.
ISP - Rev 6/95
