Yanche wrote:Just so everyone is clear as to what is being said here. Any load on any generator will have some effect on the generator. That effect may or may not be harmful.
There are three classes of home use generators:
C. Commutator with brushes
A better list:
A Inverter generators
a1 - modified sine wave
a2 - stepped sine wave approximation
a3 - pure sine wave approximation
B Brushless alternators
b1 - permanent magnet field
b2 - field magnetization controlled by current magnetically induced and can support voltage regulation
C Generators with brushes
c1 - commutator with brushes, produce DC
c2 - Slip rings used with brushes, Produce AC (I omitted this older design in my previous comments, MY BAD)
Generators have a stationary field and rotating armature. The field is fairly light. The heavy armature (power generating) coils rotate.
- slip ring designs produce AC - (probably the "original" AC generator)
- commutator designs produce DC, The commutator constantly switches what winding is connected to the output.
Alternators have a rotating field (lightweight) and the power producing windings are stationary. Much more common these days due to far lighter weight and less material.
It's not just power factor, supplied power or loads may have switching distortion (often called harmonic distortion) distorted supply voltage (even if caused by that load) can affect the source or load adversely. Both PF and distortion cause imaginary power. The current associated with imaginary power cause real resistive loss in all conductors. This loss is "real power" and heats the conductors involved (supply or load) The current involved with imaginary power is REAL, heats things and can trip breakers or overload MOS switching transistors.
Distorted voltage waveforms can confuse many electronic controls and other devices.
Many low cost inverter generators do not produce sine wave output. This can really affect electrical controls and shorten life of motors.
Upper end alternates vary the field to keep the voltage regulated. Both inverter and alternator "generators" generally have engine sag when a heavy load is turned on. A few expensive inverter generators (usually lower power units) use a battery to supply energy until the engine recovers.
AC generators (not alternators) do not bridge or switch windings . The slip ring is continuously connected to a single winding via brushes. Slip ring brush generators produce clean AC and the heavy rotating armature stores mechanical energy which helps the generator absorb surges. They still are made but generally are much heavier than alternators.
The word "alternator" is rarely used for home "generators" Both alternators and AC generators are still on that market and both work well. Material cost and weight favor alternator designs. Lables rarely tell you which design it is.