Control Techniques Unidrive Regen, Руководство по установке

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Unidrive Regen Installation Guide
23
Issue Number: 2 www.controltechniques.com
At power-up this parameter is zero. Each time the unit is enabled the supply inductance is measured and displayed by this parameter. The value
given includes the supply inductance and the inductors inserted at the supply to the sinusoidal rectifier unit. The value given is only approximate, but
will give an indication as to whether the input inductance is correct for the sinusoidal rectifier unit size.
The sinusoidal rectifier unit will attempt to hold the DC bus at the level specified by this parameter. The higher the bus voltage the better the
performance of the unit as there will be more voltage available to control the input current. The bus voltage must always be higher than the peak of
the line to line supply voltage if the unit is to operate correctly. The voltage can be set to a level up to 800V, but this only leaves 30V headroom below
the over-voltage trip level. Therefore it is best to use the default value of 700V unless the supply voltage is such that it must be raised above this level.
This parameter sets the PWM frequency and also determines the sample frequency for loops.
The sampling frequency of the control system is based on the switching frequencies as follows:
Current control
DC bus voltage control and synchronisation with the supply
Setting this parameter to 1 modifies the IGBT switching pattern so as to reduce the number of switching events. This has the following effects:
• Slightly reduced power loss in the Regen drive.
• Increased acoustic noise from input inductors.
15.06
0.16 Input inductance
ô
0.001 to 100
ð
mH RO Uni P
15.07
0.17 DC bus voltage set-point
ô
0 to 800
ð
700 Vdc RW Uni
Supply voltage
Vac
Minimum
Vdc
Recommended
Vdc
Maximum
Vdc
380 650 700 800
415 680 700 800
480 780 780 800
15.08
0.18 Switching frequency
ô
0 to 4: [3, 4.5, 6, 9, 12]
ð
0:[3kHz] kHz RW Txt P
Switching frequency
kHz
Control frequency
kHz
3 3
4.5 4.5
6 6
9 4.5
12 6
Switching frequency
kHz
Control frequency
kHz
3 3
4.5 2.25
6 3
9 2.25
12 3
15.09
0.19 High stability space vector modulation
ô
0 ~ 1
ð
0 RW Bit