16
●
Ic1p
: peak of fundamental wave capacitive current.
●
Ir3p, Ir5p, Ir7p:
peak of 3, 5, 7 harmonic resistance current.
Note:If the Angle Φ of advanced fundamental voltage of the fundamental wave current exceeds
90°, Ir1p is negative; when the angle is more than 180°, Ic1p is also negative. If the Ix
waveform is flat, Ic1p can be greater than Ixp.
●
P1
: Fundamental power consumption, i.e., the product of the effective value of the fundamental
wave resistance current and the effective value of the fundamental wave voltage. When using the
induction test method, U1 = 1000V is assumed in the instrument, and the fundamental power
consumption unit is shown as mW/KV and W/KV. The actual power consumption of the zinc oxide
arrester under running voltage can be obtained by multiplying this value with the actual voltage
value of the system (unit: KV).
●
Cx
: electric capacity of zinc oxide arrester, and the formula is as follows:
Cx =
Ic1
2
π
fU1
Ic1 is the effective value of the fundamental wave capacitance current
F
is the system frequency
U1 is the effective value of the fundamental wave voltage
When using induction test mode, U1 = 1000V is assumed in the instrument, and the unit of electric
capacity is shown as uF·kV and nF·kV. This value is divided by the actual voltage value of the
system (kV), and the actual electric capacitance of the zinc oxide arrester under running voltage
can be obtained.
●
Φ:
The Angle of advanced fundamental voltage of the fundamental wave current, which already
contains the compensation angle. The conclusions given by the instrument according to the
judgment of Φ are shown in the following table:
conclusion
Worse
Bad
Medium
Good
Excellent
Interfered
Φ
0
～
74.99°
75
～
76.99°
77
～
79.99°
80
～
82.99°
83
～
87.99°
≥88°
Note: this instrument has the automatic amplification function of the waveform, so the
amplitude of the waveform cannot represent the corresponding data value.
