PF3000 Power Filter Characteristic Tester User Manual
four bridge arms capacitive imbalance values have corresponding relationship according to the
formula derivation.
According to the theoretical analysis, imbalance vector Kbph which is determined by Ic and Ibph
can be used to adjust four-arms capacitor’s values to reach the purpose of "H" bridge balance.
C1
L1
R1
C2
L2
Harmonic
characteris
tic tester
Uout
Ibph
Ic
PC
Ibph
Figure A-4 "H" bridge capacitor group unbalance test wiring connection
According to the basic formula, we can get the formula circuit equation after simplification:
(
1
4
2
3)
4
bph
C
C
C
C
K
C
∆ + ∆
− ∆
− ∆
=
×
(A-2)
Formula (A-2) shows that the Kbph can be used as sensitive parameters to describe the
imbalance status of "H" bridge 4-arms. The balance adjustment solution of “H” bridge four-arm is
based on the Kbph value and direction. We are required to decrease the absolute value of
elements to reduce the “H” bridge imbalance. If the molecule is zero, the “H” bridge capacitor
group imbalance can be eliminated.
Formula (A-1) shows that, "H" bridge imbalance vector Kbph can easily get from total current
vector and imbalance current vector Ibph flowing through the "H" bridge capacitor group. If the
basic benchmark vector is Ic, the Kbips is value with symbol. According to the vector symbol and
value, the “H” bridge capacitor group imbalance solution is confirmed.
It is supposed that one arm of "H" bridge consists of m capacitor components in series. When "H"
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