Page 242 - Solutions Manual to accompany Electric Machinery Fundamentals

Note: An electronic version of this magnetization curve can be found in file
p86_mag.dat, which can be used with MATLAB programs. Column 1
contains field current in amps, and column 2 contains the internal generated
voltage E A in volts.

8-16. The motor described above is connected in shunt.
(a) What is the no-load speed of this motor when R adj = 120 ?

(b) What is its full-load speed?
(c) What is its speed regulation?

(d) Plot the torque-speed characte ristic for this motor.
(e) Under no-load conditions, what range of possible sp eeds can be achieved by adjusting R adj ?

S OLUTION Note that this magnetization curve has been stored in a file called p86_mag.dat. The first
column of the file is an array of ia_values, and the second column is an array of ea_values. These
values are valid at a speed n = 3000 r/min. These values can be used with the MATLAB interp1
o
function to look up an internal generated voltage as follows:

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