CONTROLLER OF NEUTRAL POINT CLAMP STYLE PWM CONTROL TYPE POWER CONVERTER

摘要

PURPOSE: To output the voltage of fundamental wave components equal to a command value by producing a switching pattern, according to the comparison results, by comparing the sine value or cosine value obtained by a conversion means with a three-phase AC voltage command. ;CONSTITUTION: The switching pattern operator 5 of a controller obtains and output a pair, for each phase, of switching pattern signals g_rp, g_rn; g_sp, g_sn; g_ip, f_in, by comparing the three-phase voltage command E_r, E_s, an E_i obtained with a coordinate converter 1 with the sine value Sin θ obtained with a sine value converter 3. And, a gate pattern operator 6 generates four sets of gate signals g_r1-g_r4; g_s1, g_s4; g_i1, g_i4 separately for each phase, based on the switching pattern signals g_rp, g_rn; g_sp, g_sn; g_ip, g_in obtained with the switching pattern operator 5, and supplies them to four pieces, for each phase, of switching elements of the power converter 5. As a result, fundamental wave voltage equal to the voltage commands Ed and E_g can be outputted while reducing the specified higher harmonics of the output voltage of the power converter 50.;COPYRIGHT: (C)1996,JPO