Turbo PMAC Users Manual Manual

L pn = L pp / √3 = 0.039 / 1.732 = 0.0225 H
Rpn = R pp / √3 = 3.0 / 1.732 = 1.732 ohms
Isat = V cmax/K c = 5.0 / (5.0/17.5) = 17.5 amps
VDC = V AC * √2 = 120 * 1.414 = 170 V
TP = 1 / (1000*f P) = 1 / (1000*9.03) = 0.000110 sec
ω n (rad/s) = 2 π ω n (Hz) = 2 * π * 200 = 1256 rad/sec
Kcp = I sat [(2 ζ ω n L pn) – R pn] / V DC = 17.5 [(2 * 0.7 * 1256 * 0.0225)- 1.732] / 170 = 3.89
Kci = I sat T p ω n 2 Lpn / V DC = 17.5 * 0.000110 * 1256 2 *0.0225 / 170 = 0.401
Ixx62 + Ixx76 = (Kcp * PWMmaxcnt) / (4 * Ixx66) = 3.89 / (4 * 1.1) = 0.884
Ixx61 = (Kci * PWMmaxcnt) / (8 * Ixx66) = 0.401 / (8 * 1.1) = 0.0456
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Delta Tau Turbo PMAC User Manual
Preparation for Experimental Tuning
Typically the experimental current-loop tuning is done through the Turbo Setup program or the PMAC
Executive program; both create the proper setup for the tests automatically. However, if you want to do
the test “manually,” follow the instructions in this section.
To prepare Turbo PMAC for this test:
• Set Ixx00 for all other motors to 0 to de-activate them.
• Set Ixx01 for all other motors to 0 to turn off the commutation. This makes sure Turbo PMAC has
enough calculation time to gather data fast enough.
• Set I7m02 to 0 for divide-by-1 to make servo update rate equal to phase update rate. This permits
Turbo PMAC to gather data every phase update.)
To set up the motor under test:
• Set Ixx00 to 1 for the motor under test to activate it.
• Set Ixx01 to 1 for the motor under test to turn on phase/current calculations. These may have been
left at zero from the earlier tests.
• Give the motor a K command to turn off the outputs
• Set Ixx71 to 1 to cripple the commutation algorithm and prevent movement during the test.
• Make sure the other setup I-variables are set as instructed above. I7m02 and Ixx71 only should be
different from what they would be in the final application.
• Start with Ixx62=0.1, Ixx61=0.0, and Ixx76=0.0 as current loop gains.
• Set Ixx77 to 3000 to provide about 10% direct current command.
In the Detailed Plot section of data gathering, specify data gathering at intervals of one servo cycle.
Select for gathering the commanded and actual direct current registers every servo cycle for the motor
under test. The addresses for these registers are found in the following table.
Setting Up Turbo PMAC-Based Commutation and/or Current Loop