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Parker 590+ series Frame 1, 2, 3, 4, 5, 6 & H. Product Manual (2012) - page 11

Control Loops

5-5

Field Control

MMI Menu Map

Set-Up Notes

1

CONFIGURE DRIVE

Use the field AUTOTUNE facility to tune the field current control loop.

AUTOTUNE

Initial Conditions

1. Main contactor open, i.e. no Start/Run signal at terminal C3.

2. Set the AUTOTUNE parameter to OFF.

3. Program Stop (terminal B8) and Coast Stop (terminal B9) should be high, i.e. 24V.

4. The motor should be stationary.

Caution

Never perform a field autotune if the motor is turning above base speed, since this will generate armature voltages

that can overvoltage the armature circuit.

Performing an Autotune

1. Set the AUTOTUNE parameter to FIELD.

2. Close the main contactor, i.e. Start/run signal to terminal C3.

3. Energise the Enable terminal (C5).

The Autotune sequence is initiated. When complete (after approximately 5 seconds), the main contactor is opened signalling the end of the sequence

and the AUTOTUNE parameter is reset to OFF.

4. Perform a PARAMETER SAVE now. Refer to Chapter 6: "The Keypad - Saving Your Application".

Autotune Failed?

The AUTOTUNE ERROR message may result if:

¾ The field terminals are open-circuit or short-circuit.

¾ More than 180% or less than 20% field voltage is required to drive the current configured in the FIELD CURRENT parameter.

¾ The natural field time-constant is greater than 5 seconds.

In these cases, a manual tuning process will be required, much like the manual tuning of the armature current loop. With manual tuning, one

convenient method of producing field current demand steps is to set the field demand (SETPOINT) to 50% and then use the drive enable to move to

and from the 'quench' and 'standby' modes to create transients. Monitor the field current at control board test-point IF, scaled 4V = 100% rated field

current.

5-6 Control Loops

Current Control

The field current loop can accept a demand directly from the plant and/or an outside field weakening loop and forms the error signal which is the

difference between demand and feedback. The error signal is fed into a P + I compensator which produces the output of the field loop, i.e. the field

firing angle signal.

The firing angle signal is translated into a certain time delay from the mains zero cross point (obtained via the same Phase-Lock-Loop as for the

armature) and this results into a firing command being issued to the field bridge every 1/2 of a mains cycle in steady-state.

Voltage Control

This offers the facility of an open-loop voltage control for motors which do not provide in the nameplate the field current rating. The field voltage is

controlled by the specified FLD. VOLTS RATIO which defaults to 90.0%. This is the maximum dc Volts that can be obtained for a given ac RMS

input in a single-phase rectifier, i.e. 370V dc for 415V ac supply. The specified ratio determines directly the firing angle at which the controller

operates and therefore the thermal effects on the field resistance as well as mains voltage variations are not compensated for. It is also worth noting

that in this mode the field overcurrent alarm is not active (since there is no current scaling) and therefore this mode is not recommended for use with

supplies much greater than the field voltage rating.

Field Weakening

Motor field weakening is used to extend the speed region of the motor above its base speed (the motor speed resulting at rated armature voltage, rated

armature current and rated field current), in a constant power mode of operation (motor torque reducing with increasing speed).

Note that the motor should be rated for field-weakened operation, in terms of rotational speed and reduced field current, before utilising this mode.

The drive includes a field weakening loop that, above base speed, can control the field current demand to the correct level required to maintain motor

back-EMF at a pre-defined level.

NOTE Field weakening is not possible when running with Armature Volts feedback. Although field weakening can be “Enabled” in this

instance, a software interlock clamps the field demand at 100% and will not allow the field weakening to reduce it.

When the back-EMF measurement is higher than the MAX VOLTS setting (default 100%) the excess voltage is presented to the field weakening gain-

limited PI controller as an error, and this controller reduces the field current demand accordingly.

The gain-limited controller is tuned as follows:

1. Ensure that the armature current, speed and field current loops are correctly tuned.

2. Enable field weakening control (FLD. WEAK ENABLE = ENABLE), with analogue tachogenerator, encoder or microtach speed feedback,

correctly installed and configured for extended speed operation.

3. Run the drive and slowly increase the speed demand so that the field is being weakened by the gain-limited PI controller. Change the MAX

VOLTS parameter down and up by 10% to generate field current transients.

4. Alternately increase the P gain (using the dc-gain parameter EMF GAIN) and reduce the integral time-constant (parameter EMF LEAD) until

the loop is correctly tuned (see the Current Loop "Tuning Hints" above).

Control Loops

5-7

It is the over-voltage of the back-EMF that provides the error which drives this controller to weaken the field, and the over-voltage occurring during

ramp through base speed is dependent on the rate of ramp. If the over-voltage is excessive, then it can be reduced most simply by switching to the

ADVANCED field weakening mode. In the STANDARD mode, provide advanced notice of the overvoltage, in order to reduce it, by employing the

lag/lead filter applied to the back-emf measurement. This filter is disabled by default through its equal lag and lead time-constant settings, increase the

lead time-constant to provide advance notice of weakening to the controller.

Notes on field weakening controller usage:

1. The use of the back-EMF filter should be limited to 3:1 ratio of lag to lead time-constants, and the field current loop and field

weakening controller may need to be de-tuned, in order to maintain overall loop stability.

2. The gain-limit of the PI controller may also be adjusted in order to optimise the balance between transient and static back-EMF over-

voltage. Lower lag time-constants and lower dc-gains result in more static back-EMF over-voltage, but allow for more back-EMF

filter advance during speed ramps. The ratio of lag to lead time-constants should be typically maintained above 10 to avoid significant

dc over-voltage on the back-EMF.

ADVANCED Mode

The ADVANCED mode of the field weakener offers the following advantages over the STANDARD mode.

1. A feedforward control is applied in addition to the gain-capped PI controller. This term, which compares the actual speed feedback to the

calculated base speed, estimates the required field weakening. The use of this control term significantly reduces the overvoltage on transition

through base speed, prior to the application of any lead-lag compensation. Transistions through base speed can be more rapid without

overvoltage as a result. In addition, false weakening of the field is eliminated for speed transients just below base speed, if the lead-lag back-

emf filter is left disabled.

2. The back-emf control loop is gain compensated for reducing field level. Motor back-emf is related directly to the motor speed, and to the

motor flux level. As a result the transfer gain from field current to back-emf is directly related to motor speed. An adaptive gain element is

included in the ADVANCED mode that increases back-emf loop gain below full speed, and this allows improved control performance at the

field weakening boundary whilst maintaining stability at full speed.

3. The speed control loop is gain compensated for reducing field level. Motor torque is related directly to both armature current and motor

flux level. An adaptive gain element is included in the ADVANCED mode that increases speed loop gain below full field, and this maintains

speed control performance into the field weakened operating region. Note that the lag-lead back-emf filter can still be applied in the

ADVANCED mode to further improve voltage control during rapid excursions into field weakening.

Standby Field

When the armature current gets quenched, a timer starts timing-out and after a certain delay (FLD. QUENCH DELAY) it will either quench the field

totally (FLD. QUENCH MODE = QUENCH) or will reduce it to 50% of the current or voltage setpoint (FIELD QUECH MODE = STANDBY). This

applies to both current and voltage modes.

The Keypad 6-1

Connecting the 6911 Keypad

The Keypad is a plug-in MMI (Man-Machine Interface) option that allows full use of the drive’s features.

It provides local control of the drive, monitoring, and complete access for application programming.

Insert the Keypad into the front of the drive (replacing the blank cover and plugging into the RS232 programming port); or mount it up to 3 metres

away using the optional panel mounting kit with connecting lead.

Refer to Chapter 3: “Installing the Drive” - Remote Mounting the Keypad.

On power-up, a calibration message is displayed. This is quickly replaced by a default

Welcome screen showing the product description and

Product Code.

The Welcome screen is at the top of the menu system.

The drive can operate in one of two modes:

Programming

Remote Control Mode: Allowing complete access for application programming

Keys

Local Control Mode:

Providing local control and monitoring of the drive

Local control keys are inactive when Remote control mode is selected and vice versa,

Local

with one exception; the L/R key toggles Local or Remote control modes and so is always

Control

operative.

Keys

The drive always initialises in Remote control mode, and with the Local control keys

inactive, it is unlikely that the motor could be started accidentally.

Figure 6-1 6911 Keypad

6-2 The Keypad

Control Key Definitions

Keys for Programming the Drive

NOTE Refer to “Navigating the Menu System”, page 6-7 for a quick-start to using the menu.

UP

Navigation - Moves upwards through the list of parameters.

Parameter - Increments the value of the displayed parameter.

Command Acknowledge - Confirms action when in a command menu.

DOWN

Navigation - Moves downwards through the list of parameters.

Parameter - Decrements the value of the displayed parameter.

ESCAPE

Navigation - Displays the previous level’s Menu.

Parameter - Returns to the parameter list.

Trip Acknowledge - Acknowledges displayed Trip or Error message.

MENU

Navigation - Displays the next Menu level, or the first parameter of the current Menu.

Parameter - Holding M down when a parameter is displayed shows that parameter’s Tag No. Repeated pressing at

a writable parameter moves a cursor across the value to allow rapid increment/decrement of the parameter value.

PROG

Navigation - When in Local mode, displays the previous MMI menu whilst remaining in Local mode enabling

changes to be made to parameters not available in Local menu. The key has no function in Remote mode.

LOCAL/

Control - Toggles between Remote and Local Control Modes for both Start/Stop (Seq) and Speed Control (Ref).

REMOTE

When toggling, the display automatically goes to the relevant SETPOINT screen, and the SETPOINT (LOCAL) screen

will have the

and

keys enabled to alter the setpoint.

The Keypad 6-3

Keys for Operating the Drive Locally

FORWARD/

Control - Changes the direction of motor rotation when in Local mode, indicated by the display. Selects between

REVERSE

two jog speeds when in Jog mode. This key has no function in Remote mode.

JOG

Control - Runs the motor at a speed determined by the JOG SPEED 1 parameter. When the key is released, the

Drive returns to “stopped”. Only operates when the Drive is “stopped“ and in Local mode. This key has no

function in Remote mode.

RUN

Control - Runs the motor at a speed determined by the LOCAL SETPOINT.

Trip Reset - Resets any trips and then runs the motor as above. Only operates when the Drive is in Local mode.

STOP/RESET

Control - Stops the motor. Only operates when the Drive is in Local mode.

Trip Reset - Resets any trips and clears displayed message if trip is no longer active.

Indications

Keypad Alarm Messages

An alarm message will be displayed on the MMI when the unit is tripped.

• The Drive has tripped.

The top line indicates a trip has occurred while the bottom line gives the reason for the trip. See

example opposite.

Acknowledge the trip message by pressing the E key. Press the STOP/RESET key to restore the Health

LED.

Refer to Chapter 7: “Trips and Fault Finding” for trip messages and reasons.

6-4 The Keypad

Keypad LEDs

OFF

There are seven LEDs that indicate the status of the Drive. Each LED is considered to operate in three different ways:

FLASH

The LEDs are labelled HEALTH, RUN, STOP, FWD, REV, and LOCAL (as SEQ and REF). Combinations of these LEDs have

ON

the following meanings:

HEALTH (OK)

RUN

STOP

Drive State

Re-Configuration

Tripped

Stopped

Stopping

Running with zero reference

Running

Autotuning

FWD

REV

Forward / Reverse State

Requested direction and actual direction are forward

Requested direction and actual direction are reverse

Requested direction is forward but actual direction is reverse

Requested direction is reverse but actual direction is forward

LOCAL SEQ

LOCAL REF

Local / Remote Mode

Start/Stop (Seq) and Speed Control (Ref) are controlled from the terminals

Start/Stop (Seq) and Speed Control (Ref) are controlled using the Keypad keys

The Keypad 6-5

The Menu System

The menu system is divided into a `tree’ structure with 9 “MENU LEVEL” main menus.

Consider these main menus to be at Menu Level 1 (refer to the The Menu System Map, page 6-8). Parameters

contained in Menu Level 1 are the most frequently used, as you descend the menu levels the parameters are less

frequently used.

The Keypad has selectable “viewing levels” which can restrict the view of the Remote menu system, refer to

"Selecting a Menu Viewing Level", page 6-17.

Below is a simple description of the main menus:

• DIAGNOSTICS: a view of important diagnostic parameters.

• SETUP PARAMETERS: contains all the function block parameters for setting-up the Drive.

• PASSWORD: contains all the Password parameters required for security.

• ALARM STATUS: a view of the alarm diagnostic parameters contained in the FUNCTION BLOCKS menu.

• MENUS: allows full or reduced menu displays on the Keypad, and selects the display language.

• SERIAL LINKS: contains all the parameters for external communications set-up and operation.

• SYSTEM: contains all the parameters for I/O configuration.

• PARAMETER SAVE: save the application/parameters.

• CONFIGURE DRIVE: a view of the important parameters used when setting-up the drive.

• FUNCTION BLOCKS: a view of all available function blocks, as seen in the Configuration Tool.

Figure 6-2 The Menu System showing Main Menus and Key Presses

6-6 The Keypad

The Local Menu

There is also a separate Local menu which provides

Local Setpoint information. This menu can be

accessed from anywhere in the Menu System by

pressing the L/R key. Holding the M key down in

the Local menu will display additional Feedback

information. A toggle to the Local menu displays

whichever is in force, Forward or Reverse,

previously selected by the FWD/REV key.

The L/R Key

The L/R key (Local/Remote) only operates when

the motor is stopped. It toggles the drive between

Local or Remote control and an appropriate menu

on the Keypad is displayed; either a Local menu

when in Local control, or a main programming

menu from the Menu System when in Remote

control.

When in Local control, the Local LEDs, SEQ and

REF, are illuminated and the RUN, STOP, JOG,

FORWARD/REVERSE, UP and DOWN local

control keys can be used to control the motor speed

and direction.

Pressing the L/R key when in Local control mode selects Remote control

Figure 6-3

mode and returns you to your previous menu in the Menu System.

Viewing the Local Menu

The PROG Key

The PROG key only operates when in Local control mode. It toggles the display between the Local menu and the main Menu System but the drive

remains in Local control. Thus, the PROG key allows you to make changes to parameters normally available in Remote control mode whilst

remaining in Local mode operation.

HINT: When operating the drive locally, it is quite useful to have a relevant parameter selected in the main Menu System for easy access.

The Keypad 6-7

Navigating the Menu System

scroll

The Menu System can be thought of as a map which is navigated using the four keys shown

opposite.

exit to

next menu/

previous

M

• Keys E and M navigate through the menu levels.

E

select parameter

menu

• The up (▲) and down (▼) keys scroll through the Menu and Parameter lists.

Menus can contain other menus at a lower level in the tree structure, parameters, or a mixture

of both.

scroll

NAVIGATING THE MENU

The keys are used as above to select a parameter (a parameter has a selection (i.e. ON/OFF) or

a value displayed on the bottom line).

increment

HINT: Remember that because the Menu and Parameter lists are looped, the Πkey can

quickly move you to the last Menu or Parameter in the loop. The keys will repeat if you

hold them down. This is an easy way to step through and view a menu’s contents.

exit to

ove

previous

E

M m

the

Changing a Parameter Value

menu

cursor

With the Parameter you want on view, three of the keys now perform different functions:

• Change a selection (i.e. ON/OFF) using the up (▲) and down (▼) keys.

decrement

• Change a value as follows:

EDITING PARAMETERS

The up (▲) and down (▼) keys increment/decrement the value at a rate determined by

the right hand character of the value, indicated by the appearance of a cursor.

♦ If the cursor is positioned as 100.0 ,then the value will change by tenths of a unit

♦ If the cursor is positioned as 100.0, then the value will change in whole units, etc.

The up (▲) and down (▼) keys will repeat if you hold them down and, at a preset point, the cursor

will progressively move one character to the left and increment/decrement the value at an increased

rate.

RAMP ACCEL TIME

Alternatively, you can move the cursor manually by pressing the M key. Repeated pressing moves

10.0 SECS

the cursor right to left along the value.

The cursor times-out after approximately half a second, so use the M key and up (▲) and down

A Parameter showing a cursor under the value

(▼) keys promptly once the cursor is in position.

NOTE

A cursor appears under all numerical values except for parameters in the Diagnostics and Alarm Status menus whose values provide

information only.

6-8 The Keypad

The Menu System Map

MENU LEVEL

DIAGNOSTICS

MENU LEVEL

RAMPS

SETUP PARAMETERS

AUX I/O

OP-STATION

SET UP

MENU LEVEL

JOG/SLACK

START UP VALUES

PASSWORD

RAISE/LOWER

LOCAL RAMP

PRESET SPEEDS

SRAMP

RATE SET 0

RATE SET 1

SPECIAL BLOCKS

PID

MENU LEVEL

ALARM STATUS

TENS+COMP CALC.

DIAMETER CALC.

MENU LEVEL

TAPER CALC.

MENUS

TORQUE CALC.

SETPOINT SUM 2

FIELD CONTROL

FLD VOLTAGE VARS

CURRENT PROFILE

FLD CURRENT VARS

FLD WEAK VARS

E

M

STOP RATES

CALIBRATION

INHIBIT ALARMS

CURRENT LOOP

BASIC, STANDARD & ADVANCED

SPEED LOOP

ADVANCED

ADAPTION

STANDSTILL

ZERO SPD.QUENCH

STANDARD & ADVANCED ONLY

SETPOINT SUM 1

SETPOINTS

INERTIA COMP

The Keypad 6-9

MENU LEVEL

TEC OPTION

SERIAL LINKS

SYSTEM PORT (P3)

P3 SETUP

5703 IN

PNO CONFIG

BISYNCH SUPPORT

MENU LEVEL

SOFTWARE

SYSTEM

CONFIGURE I/O

ANALOG INPUTS

ANIN 1 (A2)

MINI LINK

ANIN 5 (A6)

MENU LEVEL

PARAMETER SAVE

ANALOG OUTPUTS

ANOUT 1 (A7)

ANOUT 2 (A8)

MENU LEVEL

DIGITAL INPUTS

DIGITAL INPUT C4

CONFIGURE DRIVE

DIGITAL INPUT C5

DIGIN 1 (C6)

MENU LEVEL

FUNCTION BLOCKS

DIGIN 3 (C8)

E

M

DIGITAL OUTPUTS

DIGOUT 1 (B5)

DIGOUT 3 (B7)

CONFIGURE 5703

BLOCK DIAGRAM

BASIC, STANDARD & ADVANCED

INTERNAL LINKS

LINK 1

STANDARD & ADVANCED ONLY

LINK 12

6-10 The Keypad

The Keypad Menus

DIAGNOSTICS

The DIAGNOSTICS Menu table describes all the parameters in the MMI’s DIAGNOSTICS menu. These parameters are "read-only" and are very

useful for tracing configuration problems. The list is shown in MMI order, and the parameter names are as displayed by the 6901 Keypad and the DSE

Configuration Tool.

DIAGNOSTICS (MMI only)

Parameter

Tag

Range

SETUP PARAMETERS Function Blocks

SPEED DEMAND

89

⎯.XX %

Speed loop total setpoint after the ramp-to-zero block.

Refer to SPEED LOOP

SPEED FEEDBACK

207

⎯.XX %

Speed loop feedback.

Refer to FEEDBACKS

SPEED ERROR FILT

297

⎯.XX %

Speed loop error.

Refer to SPEED LOOP

SPEED LOOP O/P

356

⎯.XX %

Output from speed loop PI.

Refer to SPEED LOOP

CURRENT DEMAND

299

⎯.XX %

Current loop demand

(speed error PI output or external current demand clamped by all the current limits).

Refer to CURRENT LOOP

CURRENT FEEDBACK

298

⎯.XX %

Scaled and filtered current feedback.

Refer to FEEDBACKS

CURRENT FBK. AMPS

538

⎯.XX AMPS

Scaled and filtered armature current in Amps.

Refer to CURRENT LOOP

IaFbk UNFILTERED

65

⎯.XX %

Scaled current feedback (unfiltered).

Refer to CURRENT LOOP

IaDmd UNFILTERED

66

⎯.XX %

Scaled current demand (unfiltered).

Refer to CURRENT LOOP

POS. I CLAMP

87

⎯.x % (h)

Positive current clamp.

Refer to CURRENT LOOP

NEG. I CLAMP

88

⎯.x % (h)

Negative current clamp.

Refer to CURRENT LOOP

The Keypad 6-11

DIAGNOSTICS (MMI only)

Parameter

Tag

Range

SETUP PARAMETERS Function Blocks

ACTUAL POS I LIM

67

⎯.x % (h)

Overall positive current limit value.

Refer to CURRENT LOOP

ACTUAL NEG I LIM

61

⎯.x % (h)

Overall negative current limit value.

Refer to CURRENT LOOP

INVERSE TIME O/P

203

⎯.XX %

Inverse time clamp output level.

Refer to INVERSE TIME

AT CURRENT LIMIT

42

FALSE / TRUE

Current demand is being restrained by the overall current clamp.

Refer to CURRENT LOOP

AT ZERO SPEED

77

FALSE / TRUE

At zero speed feedback.

Refer to STANDSTILL

AT ZERO SETPOINT

78

FALSE / TRUE

At zero speed demand.

Refer to STANDSTILL

AT STANDSTILL

79

FALSE / TRUE

AT ZERO SPEED and AT ZERO SETPOINT.

Refer to STANDSTILL

RAMPING

113

FALSE / TRUE

The SETPOINT ramp function block is limiting the rate of change of Speed Setpoint.

Refer to RAMPS

PROGRAM STOP

80

FALSE / TRUE

State of program stop (Terminal B8). When B8 is at 24V, then PROGRAM STOP is

FALSE.

Refer to SELECT

COAST STOP

525

FALSE / TRUE

State of coast stop (Terminal B9). When B9 is at 24V, then COAST STOP is FALSE.

Refer to SELECT

DRIVE START

82

ON / OFF

Controller start/run command.

Refer to SELECT

DRIVE ENABLE

84

ENABLED / DISABLED

Drive speed and current loop are enabled/quenched.

Refer to SELECT

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