Drive Application Software Application Set Application Set Title Drive Product File Name for (AS) Date - Revision Process Trim, Speed Loop PowerFlex 700VC AS_PF700VC_ProcessTrim_Speed.doc 6/10/03 01 Attention: This document and related file(s) are designed to supplement configuration of the listed drive product. The information provided does not replace the drive products user manual and is intended for qualified personnel only. Description: Process Trim application used to take a feedback signal from a dancer or load cell and trim the speed loop. Limitations: Options & Notes: Default configuration for 3 wire control through digital inputs may be changed to 2wire control or for operation through 20-COMM-x module. After downloading *.dno file, the Motor Data and Motor Tests portions of the Basic Startup should be performed through the LCD HIM. Then enable the Process Trim loop by setting P125 [PI Control], B0 = 1. Drive Input & Output Connections: Inputs Function DI 1 Start DI 2 Stop DI 3 Jog1 DI 4 DI 5 DI 6 AI 1 Speed Reference AI 2 Process Trim Feedback AI 3 NA Outputs Function DO 1 DO 2 DO 3 AO 1 AO 2 AO 3 NA AS_PF700VC_ProcessTrim_Speed.doc Form Revision – A Page 1 of 3 Description Description Drive Application Software Application Set Parameter Configurations Changes from Default Parameter Settings Par Name Value 4 - FVC 53 Motor Cntl Sel Vector 79 Speed Units 1 - RPM 90 Speed Ref A Sel 1 – Analog In 1 91 Speed Ref A Hi 1800 RPM 92 Speed Ref A Lo 0 RPM 363 Digital In3 Sel 10 – Jog 1 125 PI Control 127 PI Setpoint 129 PI Integral Time 130 PI Proportional Gain B0 = 1 Application Dependent Application Dependent Application Dependent 131 PI Lower Limit -23.1 % 132 PI Upper Limit 23.1 % Link Description Sets the drive for flux vector control. Sets speed parameters to be displayed as RPM instead of Hz. Analog Input 1 is the speed reference, which typically comes from a PLC or potentiometer. Corresponds to the value in parameter 322 [Analog In 1 Hi] Corresponds to the value in parameter 323 [Analog In 1 Lo] Jog input Enables Process PI. Sets the % of the Analog In 2 feedback from the dancer or load cell that the user wishes to maintain. A smaller value makes the integral term more responsive. See tuning tips below. A larger value makes the proportional term more responsive. See tuning tips below. This limits the ouput of the process trim to -30 Hz (50% of base motor speed). It is based on 100% PI output = Max Freq (default of 130 Hz). 23.1% = 30Hz / 130Hz x 100% This limits the ouput of the process trim to 30 Hz (50% of base motor speed). It is based on 100% PI output = Max Freq (default of 130 Hz). 23.1% = 30Hz / 130Hz x 100% Tuning Tips: 1. After downloading the *.dno file, the Motor Data and Motor Tests portions of the Basic Startup should be performed through the LCD HIM. Then enable the Process Trim loop by setting P125 [PI Control], B0 = 1. 2. Set the Proportional Gain To tune the PI loop, start with the proportional gain. A. Set P129 [PI Integral Time] = “0”. Starting with [PI Integral Time] = “0” will make it easier to tune [PI Prop Gain]. B. Set P130 [PI Prop Gain] = “1”. C. Leave the line stopped and verify that the Process Trim drive can hold tension at 0 speed without going unstable. • Start the drive and see if it holds the dancer or load cell at the desired setpoint. • If the drive is unstable try setting [PI Prop Gain] lower in increments of 0.1 or 0.05 and restart the drive until it is stable. [PI Prop Gain] can be adjusted with the PowerFlex 70 winder drive running if desired. • If the winder is stable, increase [PI Prop Gain] in increments of 0.1 or 0.05. • Stop the drive. • Set [PI Prop Gain] to approximately 60% of the value where the drive goes unstable. D. To verify that the Proportional gain is set appropriately, perform the following: AS_PF700VC_ProcessTrim_Speed.doc Form Revision – A Page 2 of 3 Drive Application Software Application Set • • • • • Set the line to run at about 10% of nominal run speed for testing purposes. This will make the PI loop easier to tune initially. Start the Process Trim drive. Start the system. [PI Prop Gain] may already be adequate from the previous step. However, if the winder becomes unstable, lower [PI Prop Gain] in increments of 0.1 or 0.05 and restart the Process Trim drive until it is stable. Once [PI Prop Gain] is set so that the Process Trim drive is stable, stop the line. FYI: Notice that with [PI Prop Gain] set correctly, and [PI Integral Time] set to zero, there will still be error in the PI loop. In other words, the dancer won’t be at the position set by the PI setpoint until we add [PI Integral Time]. 3. Now we will set [PI Integral Time] to get rid of steady state error and bring the dancer into the correct position. A. Leave [PI Prop Gain] at the value determined above. B. Set [PI Integral Time] = 2 seconds. C. To verify that the Integral gain is set appropriately, perform the following: • Start the line (still at 10% of line speed). • If the drive is stable, reduce [PI Integral Time] in small increments of 0.1 to 0.5 seconds. • If drive is unstable, increase [PI Integral Time] in small increments of 0.1 to 0.5 seconds. • Once [PI Integral Time] is set correctly, there should only be a small amount of overshoot Process Trim drive, then the dancer settles down and maintains the setpoint. • Stop the line. 4. Verify Operation at High Speed and During Accels/Decels A. Once [PI Integral Time] and [PI Prop Gain] are set, test the winder at higher line speeds. • Start the line. • Increase the line speed in 10 – 20% increments. • Adjust [PI Prop Gain] and [PI Integral Time] in small increments if necessary (if the Process Trim drive becomes unstable). B. Next perform accelerations and decelerations on the line to verify that the Process Trim drive keeps up during speed changes. • Make small adjustments to the scaling for Speed Ref A and/or to the PI loop if necessary. AS_PF700VC_ProcessTrim_Speed.doc Form Revision – A Page 3 of 3