PF3000 Power Filter Characteristic Tester User Manual
bridge imbalance vector is Kbph, from the expression (A-3), the change value of capacitance can
be calculated.
1
1
4
bph
C
m K
C
∆ = × ×
×
(A-3)
The formula:
ΔC1: The change in capacitance values of the capacitor element which need to be adjusted.
m: the number of capacitor components which connect in series in one arm of the "H" bridge.
C1: the average value of the capacitance
While measuring the Ic and Ibph in positive direction as figure A-3, we need to measure the “H”
bridge balance adjustment in the following rules:
1)
ΔC1> 0
：
reduce the capacitance on NO.1 arm of the "H" bridge, reduce the capacitance on
NO.4
arm of the "H" bridge, increase on NO.2 arm of the "H" bridge, increase on NO.3 arm of
the "H" bridge, and make the amount of the adjustment value of capacitance equal to the
ΔC1,
then the "H" bridge capacitor is adjusted to the equilibrium state.
2)
When ΔC1 <0, increase the capacitance on the NO.1 arm of the "H" bridge, increase the on
the NO.4 arm of the "H" bridge, reduce on the NO.2 arm of the "H" bridge, reduce on the NO.3
arm of the "H" bridge, and make the amount of adjustment value of capacitance equal to
ΔC1,
then the "H" bridge capacitor group can be adjusted to the equilibrium state.
3)
When ΔC1 = 0, it is unnecessary to adjust the "H" bridge capacitor to balance.
According to the above method, we can change the state that “H” bridge balance adjustment
depends on the experience to achieve the quantitative adjustment of “H” bridge capacitors
imbalance.
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