2 Presentation Contents IntroductionEtherCAT Configurator walkthroughSystem Configuration Wizard walkthroughSystem Information ViewerComplete setup of a single axis on an ACS drive
3 IntroductionThis presentation is a step-by-step setup of the MC4Unt trainer unit. It is meant to give a flavor of what a real system setup is like.Setup in the presentation was done using SPiiPlus MMI Application Studio 2.10 software. The latest version can be found at acsmotioncontrol.comThere are three main setup tasks for the trainer unit:EtherCAT network configurationSystem configurationAxis setup and tuningThe trainer unit has three axes. This presentation covers setup of one axis, the other two are up to you!
5 Establish Communication with Controller Connect an Ethernet cable between the PC and the MC4U (J6-ETH1)Open the MMI, and User Mode Driver (if not already running)Set ‘Controller IP Address’ to and make sure your PC is on the same network, then click ‘Connect’When connection is established, the workspace window shows a green LED next to the connected controller’s serial number
6 Add Components to Workspace Right-click on the controller in the workspace window and select ‘Add Component’ to add the following:Setup Adjuster WizardSetup System Configuration WizardSetup EtherCAT ConfiguratorUtilities System Information ViewerUtilities Communication TerminalApplication Development Program Manager
7 EtherCAT Configurator Double click ‘EtherCAT Configurator’ component in the workspace tree to openSelect ‘Scan System’ and the connected EtherCAT network will be displayedClick ‘Generate Configuration’ to save to flashWait for controller to rebootClose EtherCAT Configurator
8 System ConfigurationDouble click ‘System Configuration Wizard’ in the workspace tree to openSelect ‘Change System Configuration’ radio button, click nextLeave application details blank, click nextClick ‘Approve All’ at bottom of screen, click nextWhen prompted to save configuration to controller’s flash, select yes, and OK to rebootClick next to skip COC and Print Reports. Click ‘Finish’ to close System Configuration Wizard
9 System Information Viewer Double click ‘System Information Viewer’ in the workspace tree to openAny relevant information about a system can be found using the System Information Viewer, as well as save/load system information
10 System Information Viewer For instance, to view which IO are available: look under System Configuration Network Units Unit 0 Inputs/Outputs AssignmentLooking at the pane to the right, there are 8 digital I/O, and 4 analog I/O
11 Adjuster WizardDouble click ‘Adjuster Wizard’ in the workspace tree to openSpecify you are working with Axis 3Select ‘Setup New System or Controller’ optionClick next to get to ‘Initialization’Leave user information blank, click next to get to ‘Axis Structure’
12 Adjuster Wizard: Axis Structure Specify axis structure as ‘Single Motor’Specify motor-load topology as ‘Rotary Motor and Rotary Load – Direct Drive’Set feedback topology as ‘Single, on motor’Apply user units to motorSelect ‘Degrees’ as rotary unitsPress ‘Next’ button
13 Adjuster Wizard: Motor Press the ‘+’ button to add a new motorEnter the following motor data:Click nextMotor Type3-phase DC Brushless/AC ServoNominal Current4.4 Amps (peak of sine)Peak Current8.48 Amps (peak of sine)Maximum Velocity7000 RPMNumber of Poles6Back EMF Constant39 V/kRPMPhase ConnectionStar / Wye PhasePhase Resistance3.42 Ohm
14 Adjuster Wizard: Drive Press the ‘+’ button to add a driveThe ACS drive will automatically be recognized except supply input voltage and/or frequencySpecify the input voltage as 110VSpecify frequency as 60HzClick next
15 Adjuster Wizard: Motor Feedback Press the ‘+’ button to add a new motor feedbackSelect the motor feedback type as ‘Incremental Quadrature Encoder’Specify the resolution as 2048 lines per revolutionSet the external multiplier to 1Click next
16 Adjuster Wizard: Calculate Parameters Click ‘Calculate Parameters’A list of all calculated parameters different from current values is shownClick ‘Apply Changes’ to update all parameters to the newly calculated valuesClick next
17 Adjuster Wizard: Safety and Protection Skip to ‘Current Limits’ by clicking on it in the task paneThe adjuster sets current limits to prevent damage to the motor based on info entered in ‘Components’. It is important to verify it is correctClick next to get to ‘Position Errors’Position error parameters are set automatically too, but these may need to be relaxed temporarily for tuning purposes!!! Important Safety Info !!!
18 Adjuster Wizard: Verification Skip to ‘Switches’ under the ‘Verification’ heading by clicking on it in the task paneVerify upper and lower limit switch functionality and inverse logic if necessaryClick next to get to ‘Stop, Alarm and Brake’Verify Hardware Emergency Stop functionality and inverse logic if necessaryClick next!!! Important Safety Info !!!
19 Adjuster Wizard: Axis Setup and Tuning The Axis Setup and Tuning process is covered in detail in the ‘SPiiPlus Time Domain Tuning’ presentation, but in general involves:Current loop tuningMotor commutationVelocity loop tuningPosition loop tuning
20 Adjuster Wizard: Axis Setup and Tuning ACS utilizes a cascaded control loop structure, ideal for motion control applications:Current loopVelocity loopPosition loopThe position loop generates a command to the velocity loopThe velocity loop generates a command to the current loop
21 Adjuster Wizard: Axis Setup and Tuning Tuning rules of thumb:For current and velocity loops:Begin by setting proportional and integrator gains low (usually 10 is fine for both)Start by doubling proportional gain until response is noisy, then reduce by halfKeep proportional gain fixed and begin doubling integrator gain until roughly 10-15% overshoot is observedFor position loop:Start low (usually 10) and begin doubling until position error is minimized.Make sure position error while moving at constant velocity is not noisy.
22 Adjuster Wizard: Current Loop Tuning Set both SLIKP and SLIKI = 10 (start out low)Default current level is 10% with 4ms pulse width. These values are fine, do not change.Click ‘Scope Autoset’ and ‘Run’Double SLIKP until high frequency effects (noise) or overshoot are present, then reduce by half.Typical values: 50 – 500Changing SLIKI should not require returning the change SLIKPDouble SLIKI until overshoot is excessive, then reduce by half. Overshoot should be roughly 10-15%Typical values: 1000 – 10,000
23 Adjuster Wizard: Current Loop Tuning SLIKP = 25, SLIKI = 10 Not responsive enoughSLIKP = 100, SLIKI = 10 Too aggressive (excessive overshoot)SLIKP = 75, SLIKI = 10 OkaySLIKP = 75, SLIKI = 1000 Not responsive enoughSLIKP = 75, SLIKI = Too aggressive (excessive overshoot)SLIKP = 75, SLIKI = Well tuned
24 Adjuster Wizard: Commutation Commutation is the process of keeping current vector perpendicular to motor magnetic field vector.Handled automatically in brush DC motors, and not necessary in steppers operating in micro-stepping mode.At controller startup the magnetic field orientation of a BLDC motor is not known and needs to be found. The adjuster has a facility for finding it and setting the commutation angle.Once found, the commutation angle is kept track of using motor feedback (encoder)
25 Adjuster Wizard: Commutation Adjuster based commutation only needs to be done once during initial axis setup.Once axis is properly setup and tuned, ACSPL+ COMMUT command can be used instead.COMMUT command pings motor three times and finds commutation angle with very little physical motion.If motor is equipped with hall sensors, commutation angle is based on first hall state transition, and COMMUT command is not necessary.
26 Adjuster Wizard: Commutation In the commutation dialog, click the ‘default’ button to tailor the commutation process for this particular axisClick ‘Start Commutation’On top of finding the commutation angle, a number of magnetic pitches will be measured and checked against encoder feedback to verify settingsOn successful commutation, click next twice to skip to ‘Position and Velocity Loops’
27 Adjuster Wizard: Position and Velocity Loops Select ‘Velocity Loop’Click ‘Motion Manager Autoset’, and ‘Scope Autoset’The only variables you need to be concerned with in velocity loop tuning are Proportional Gain (SLVKP), and Integrator Gain (SLVKI)Start SLVKP, SLVKI low and use a similar tuning approach as in current loopIn Motion Manager, click ‘Enable Motor’ and ‘Start Motion’
28 Adjuster Wizard: Position and Velocity Loops SLVKP = 100, SLVKI = 10 Not responsive enoughSLVKP = 2300, SLVKI = 10 Too aggressive (noisy)SLVKP = 400, SLVKI = 10 OkaySLVKP = 400, SLIKI = 200 Not responsive enoughSLVKP = 400, SLVKI = 2000 Too aggressive (excessive overshoot)SLVKP = 400, SLVKI = 700 Just right
29 Adjuster Wizard: Position and Velocity Loops Select ‘Position Loop’Click ‘Motion Manager Autoset’ and ‘Scope Autoset’Enter the following settings in the Motion Manager:Click ‘Enable Motor’ then ‘Start Motion’
30 Adjuster Wizard: Position and Velocity Loops The only variable you need to be concerned with in position loop tuning is Proportional Gain (SLPKP)Start SLPKP low and double until position error is minimized while making sure it is not noisy at constant velocity.
31 Adjuster Wizard: Position and Velocity Loops SLPKP = 1 Not responsive enoughSLPKP = 500 Too aggressive (noisy)SLPKP = 100 Position error minimized
32 Adjuster Wizard: Save to Flash Once all previous steps are complete the system is now setup and tuned. Save to flash so it will be available on controller startup.