Chorus Technology

**Visualize Chorus®**
*This page may take a while to download, please be patient.*

**Conventional 3 Phase Motor**

Download as Quicktime Movie.
This picture shows 3 rotating sets, which are graphical representations
of stator conductor currents.

__Middle Set:__ The middle picture is the fundamental. This
is what a pure sine wave looks like in a motor which has 2 poles; the north
and south pole rotate around the middle. This field does not show any harmonic
content. It rotates at a constant speed.

__Right Set:__ The right picture shows the 5th harmonic. Note
that it spins in the opposite direction, and at 5 times the speed, of the
fundamental. In this picture, it is a braking torque.

__Left Set:__ The left picture shows what happens in the motor
when the fundamental and the 5th harmonic are both flowing. The braking
torque appears as a variation in fundamental speed and magnitude. All the
elements of the set do not move together. This greatly harms efficiency,
and increases heating.

Download as Quicktime Movie.
The sets in this picture are the Chorus equivalent, showing the
5th harmonic.

__Middle Set:__ The middle, showing the fundamental, is unchanged
from the 3 phase version.

__Right Set:__ The right, on the other hand, has been altered
because of the features unique to Chorus (see the tutorial document).
The 5th harmonic no longer rotates in the opposite direction of the fundamental.
Instead, it moves in the same direction, and at the same speed. Note, too,
that there are 10 "bumps" on the ring. Each pair of bumps represents
a pair of poles. So the 5th harmonic here, as described in the Tutorial,
is acting as a 10 pole field, rotating in the same direction and at the
same speed as the fundamental.

__Left Set:__ The left picture shows the combination of the
5th harmonic and the fundamental in a Chorus machine. The shape is
different than the pure fundamental, but all the elements of the set move
together. The 5th harmonic, which had previously been a braking torque,
becomes a boosting torque. This increases the output of the motor, while
increasing efficiency.

Note that the concept shown here has been proven.
The Chorus was run with only 5th harmonic content, and the rotor spun
at the same speed as the fundamental, with a substantial torque. Full data
is available in the file: pure_fif.xls.zip.
*Animation is provided for demonstration purposes, and it is not necessarily
to scale. *