Regarding Power Harmonics; Japanese Power Harmonic Suppression Guideline - Mitsubishi FR - S500 Instruction Manual

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.5.9 Regarding power harmonics

The inverter may generate power harmonics from its converter circuit to affect the
power generator, power capacitor etc. Power harmonics are different from noise and
leakage currents in source, frequency band and transmission path. Take the following
counter measure suppression techniques.
The following table indicates differences between harmonics and noise:
Item
Frequency
Environment
Quantitative
understanding
Generated amount
Affected equipment
immunity
Suppression example Provide reactor.
Suppression technique
Harmonic currents produced
on the power supply side by
the inverter change with such
conditions as whether there
are wiring impedances and a
power factor improving
reactor and the magnitudes of
output frequency and output
current on the load side.
For the output frequency and output current, we understand that they should be
calculated in the conditions under the rated load at the maximum operating frequency.
CAUTION
The power factor improving capacitor and surge suppressor on the inverter output
side may be overheated or damaged by the harmonic components of the inverter
output. Also, since an excessive current flows in the inverter to activate overcurrent
protection, do not provide a capacitor and surge suppressor on the inverter output
side when the motor is driven by the inverter. To improve the power factor, insert a
power factor improving reactor in the inverter's primary side or DC circuit. For full
information, refer to page 18.
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.5.10 Japanese power harmonic suppression guideline

Harmonic currents flow from the inverter to a power receiving point via a power
transformer. The harmonic suppression guideline was established to protect other
consumers from these outgoing harmonics.
1) [Harmonic suppression guideline for household appliances and general-purpose
products]
The "harmonic suppression guideline for household appliances and general-purpose
products" issued by ex-Ministry of International Trade and Industry (present Ministry
of Economy, Trade and Industry) in September, 1994 applies to the FR-S500 series
other than the three-phase 400V class. By installing the FR-BEL or FR-BAL power
factor improving reactor, this product complies with the "harmonic suppression
techniques for transistorized inverters (input current 20A or less)" established by the
Japan Electrical Manufacturers' Association.
Harmonics
Normally 40th to 50th degrees or
less (up to 3kHz or less)
To-electric channel, power
impedance
Theoretical calculation possible
Nearly proportional to load
capacity
Specified in standard per
equipment
NFB
Power factor
improving AC reactor
High frequency (several 10kHz
to MHz order)
To-space, distance, wiring path
Random occurrence, quantitative
grasping difficult
Change with current variation
ratio (larger as switching speed
increases)
Different depending on maker's
equipment specifications
Increase distance.
Do not provide power factor
improving capacitor.
20
Noise
Power factor
improving DC reactor
Motor
IM