APPENDIX 21
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Appendix 3 Active Power Consumption/Regeneration, and Reactive Power and Power Factor Lead and Lag
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Appendix 3.1 Active Power
NOTE
Appendix 3.2 Reactive Power
Appendix 3 Active Power Consumption/Regeneration,
and Reactive Power and Power Factor Lea
and Lag
In the 3166, the polarity of active power is positive ("+") for consumption
power and negative ("-") for regeneration power. The phase difference of the
current versus the voltage for consumption power ranges from -90
｡
to +90
｡
,
and for regeneration power ranges from -180
｡
to -90
｡
and from +90
｡
to +180
｡
.
Of the types of power mentioned above, only the data for consumption power
is added for the consumption power integration +WP. Similarly, only the data
for regeneration power is added for -WP. ΣWP indicates the total power
integration, balancing consumption and regeneration.
Normally, power that is supplied (consumed) flows from the power supply to
the load, but in equipment that uses a motor for motive power (such as an
elevator), power sometimes returns to the power supply (is regenerated) when
the load is light, etc.
This power meter permits selection of one of two measurement methods for
reactive power.
a.Not using the reactive power meter method
This method, used in most power meters, derives the reactive power indirectly
from calculations based on direct measurements of active power and apparent
power (the product of the real values for voltage and current, including
harmonic wave components). Therefore, in cases where the composition of the
harmonic wave components included in the voltage and current differs, the
polarity only is determined through the reactive power method. For lagging
phases, "+" is added; for leading phases, "-" is added. The phase difference of
the current versus the voltage for consumption power ranges from 0
｡
to +180
｡
for both lagging and leading phases, respectively.
b. Using the reactive power meter method
This method measures the reactive power directly, in the same manner as
reactive power meters that are installed at the locations of high-demand power
consumers. Using this method eliminates the effects of an imbalance or
asymmetry between lines being measured. In addition, measurement values
are calculated using only those voltage and current components that are of the
same frequency.
The polarity is the same as when not using the reactive power meter method.
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