CONCATENATION

t

a = — = ratio of poles,

/ = supply frequency.
Pull synchronous speed of the first motor then is:

43

(1)

= n'

of the second motor:

(2)

(3)

At slip 5 and thus speed ratio (1 — s) of the first motor, its
speed is:

= (i -*)i> (4>

and the frequency of its secondary circuit, and thus the frequency
of the primary circuit of the second motor:

tf',
synchronous speed of the second motor at this frequency is:

sSfQ = s 4;

the speed of the second motor, however, is the same as that of
the first motor, /S,

hence, the slip of speed of the second motor below its synchronous
speed, is:

g _ M gj _. = i __ a**. i -t

n J n \n n /

and the slip of frequency thus is:

Xl x
.,-«(!-a),

*' = s (1 + a) - a. (5)

This slip of the second motor, $', becomes zero, that is, the
couple reaches the synchronism of concatenation, for:

(6)