Megger MPQSIM, User Manual

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ADDENDUM B - SAMPLE DEMAND TRAINING
AVTMMPQSIM Rev 1 May 2017
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However the power triangle still holds true.
√
The more reactive power in a system the greater the amount of apparent power
(KVA) is required. As inductive loads are added to a network they increase the lag in
the current. This increases the amount of reactive power in that network. The energy
provider needs to create larger amounts of apparent power to carry that burden. By
switching in a capacitive load such as a capacitor bank, this compensates for the
lagging current and therefore reduces the reactive power in the network. This means
the energy provider can produce less apparent power to run the network. This makes
the energy provider more efficient.
c.
Set the Current phase angles on the PQ Simulator back to nominal.
8. Harmonic Effects on the Power Triangle
a. View the demand values on the DVM screen of the MPQ Analyzer.
NOTE: the
√
b. Change the Phase A Current phase angle on the PQ Simulator to -30°. The
KVAR on Phase A increased due to the increase in reactive current caused by
the added inductive load.
c. Turn ON the Phase A Voltage and Current Harmonics on the PQ Simulator. The
power triangle does NOT hold true
√
.
The power triangle only holds true for sinusoidal waveforms. Once harmonics are
introduced the waveform is no longer sinusoidal, therefore the power triangle will
have errors. In the real world virtually all power will have some amount of harmonics.
This means that calculating a single power parameter based on the other two will
always have some error. In a PQ Instrument these values need to be measured values
not calculated values.
There is now a difference between the DPF and the TPF.
This is because the Displacement Power Factor (DPF) is the power factor of the
fundamental value only (COS of the phase angle between the voltage and current).
The True Power Factor (TPF) is the power factor of the fundamental plus the
harmonics (TPF = KW/KVA).
The greater the difference between the TPF and DPF, the greater the harmonic
content.
d. Set the Current phase angles on the PQ Simulator back to nominal.