Usm Reactors
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Transcript of Usm Reactors
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7/28/2019 Usm Reactors
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Reactors
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Reactor
A consumer whose load includes a high proportion of variable speed motor drives and/or other harmonic generating loads may require a
detuned capacitor system. This would perform the function of power factor improvement whilst preventing any amplification of harmonic
currents and voltages caused by resonance between capacitors and inductances in the mains.
USM offers single and three phase filter reactors for this purpose. The low-loss reactors are made of specially selected tra nsformer sheets
and manufactured in flat or round copper wire technology.
They are dried and impregnated in a vacuum which ensures they can withstand high voltages and maintain a long operating life. Depending
on their rated power. the reactors are provided with either terminal blocks or terminal lugs/cables.If the operating temperature of 120
oC is exceeded, the reactor circuit is disconnected by a thermal switch(included as standard).
Reactor for Detuned Capacitor BanksConstruction
Adjusted rating
The adjusted reactor is designed to create exactly the required
output of reactive power, allowing for the internal voltage rise inside
the resonating circuit formed together with the capacitor connected
in the circuit. Note that exact sizing of the capacitor is necessary.
Non-adjusted rating
The non-adjusted reactor is matched to a power capacitor with
standard rating at mains voltage.
This allows for additional installation of detuning reactors in existing
non-detuned systems, however, it will lead to increased output of
kvar due to voltage rise inside the resonance circuit.
Example
25kvar 400V 60Hz, detuned to 245Hz(p=6%)*
capacitor:capacitance of standard capacitor: 414 F (3 138 F)
reactor:
required reactance of the reactor: XL = XC p= 6.4 0.06 = 0.384
Example
25kvar 400V 60Hz, detuned to 245Hz(p=6%)*
capacitor:
required reactance of the reactor:
XL = XC p= 6.82 0.06 = 0.41
* Simplified calculation (single phase)
* tuning frequency: 189Hz (p=7%, 50Hz), 227Hz (p=7%, 60Hz)
204Hz (p=6%, 50Hz), 245Hz (p=6%, 60Hz)
Pcurrent for PFC 25kvar 400V 60Hz: 1 = = 62.5A
U
Uvoltage at capacitor terminations: UC = = 426V
1-p
1adjustment of the capacitance: C = = 389
UC 2 f
reactor:1
reactance of the capacitor: Xc = = 6.822 f C
XLrequired inductance: L = = 1.09mH
2 f
1reactance of the capacitor: Xc = = 6.4
2 f C
XLrequired inductance: L = = 1.02 mH
2 f
resulting PFC current: Xtotal = XC - XL = 6.02
U 400VI = = = 66.7A
Xtotal 6
Q= U I = 26.7 kvar
Design three phase, iron core, double air gapCore Grain-oriented cold rolled electrical steel
Protection class IP00, indoor mounting
Insulation class H class
Cooling natural cooling
Winding material Double enamelled copper wire. insulation class "H"
Impregnation standard dip varnish coating
Terminals terminal blocks, cable lags, or temperature-proof
flexible cables
Insulation winding to core 3 kv, nomex aramid paper
temperature class c (220oC)
Temperature monitoring temperature switch, response class 120oC
Adjustment accuracy L=+3%
Standards VDE 0570 Part 2 / IEC 96/104/CD
Tolerance of inductance 3%+_
Load Losses
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Reactor
*The other voltage, frequency,7%/13%/p(%) on request.
Fig 2
Reactors:
SC
Fig 1
E
B MAX
XAMC
D
A MAX
THS
4-FG
- WIRE
TH SWITCH TERMINAL
E
B MAX
D
A MAX
THS
4-FG
TH SWITCH TERMINAL
XAM
C
Dimensional