To obtain a starting apparatus by which the heat generating amount of every thyristor starting device is reduced by a method wherein output currents of two or more thyristor starting devices used to start an identical synchronous machine are balanced.

A starting apparatus is provided with two thyristor starting devices 1a, 1b in such a way that DC outputs of rectifiers 4a, 4b which convert an alternating current into a direct current are converted into variable-frequency AC power by inverters 6a, 6b so as to be supplied to a synchronous machine 2, that current reference signals Ira's of the rectifiers 4a, 4b are adjusted by speed regulators 11a, 11b so as to make the rotational-speed set value Nra of the synchronous machine 2 agree with a rotational speed N and that current regulators 14a, 14b by which ignition pulses to the rectifiers 4a, 4b are adjusted so as to make the current reference signals Ira's agree with converter currents Ida's of the rectifiers 4a, 4b are provided. Then, an unbalanced-current compensator 20a corrects the rotational-speed set value Nra in such a way that the current reference signal Ira of the own thyristor starting device 1a and the current reference signal Irb of another thyristor starting device 1b are balanced.