Rockwell Automation Publication 750-AT006D-EN-P - January 2022 63
Chapter 4
Auto Tuning
The Autotune function is used to measure motor characteristics. It is composed of several individual tests, each of which is intended to
identify one or more motor parameters. These tests require motor nameplate information to be entered into the drive parameters. Although
some of the parameter values can be changed manually, measured values of the motor parameters can provide the best performance.
10:910 [Autotune] determines and performs four main types of tests that are summarized as follows:
• General Modes
– Autotune defaults to Ready and performs a direction test.
- 10:910 [Autotune] = Ready (0)
- 10:910 [Autotune] = Direction (1)
• Motor Electrical Parameters
– Autotune performs static and dynamic tests to measure motor electrical parameters.
- 10:910 [Autotune] = Static MtrID (2) —This test is available for induction motors only.
- 10:910 [Autotune] = Rotate MtrID (3)
• Inertia Tests
– Autotune performs a dynamic bump test that initiates momentary motor rotation to measure inertia.
- 10:910 [Autotune] = InertiaMotor (4)
- 10:910 [Autotune] = InertiaTotal (5)
• Gain Calculation
– Autotune calculates control loop gains, filter bandwidths, and dynamic limits.
- 10:910 [Autotune] = BW Calc (6)
- 10:910 [Autotune] = JMtr BW Calc (7)
- 10:910 [Autotune] = JTotalBWCalc (8)
More detail about these tests is provided in the rest of this chapter.
General Modes
This section covers the general Autotune modes.
10:910 [Autotune] = Ready (0) – Indicates that the Autotune function is available. Autotune returns to Ready (0) after a test from one of the
other settings. After it returns to Ready (0), another start transition is required to operate the drive in Normal mode.
10:910 [Autotune] = Direction (1) – Enables the Autotune function to perform the Direction Test. After selecting this value, you must issue a
start command to begin the test. The Direction Test allows you to determine if the motor rotates in the desired direction - either clockwise
or counterclockwise for a forward velocity command. The Direction Test also allows you to check and if necessary configure the encoder (if
used) so the encoder feedback count increases in value for a forward velocity command.
Motor Electrical Parameters
Autotune Electrical tests have an effect on motor electrical parameters that are used in the current loop. Calculation of user-entered
parameters are selected by 10:510 [MtrParam C/U Sel] and 10:444 [VCL CReg C/U Sel] as described in the following sections:
• Configuration
on page 63
• Modes on page 67
Configuration
10:510 [MtrParam C/U Sel] allows either calculated or user-entered parameters to be applied to motor electrical gains. It also allows you to
transfer calculated parameter values to user-entered parameter values so that you can use them as a starting point for manual tuning, if
desired. Parameters are given in Table 21.
To Next Page
Loading...
Need help?
General
