SPATIAL VECTOR MODULATION METHOD OF AC-AC DIRECT CONVERTER

• Main Author: TADANO YUGO
• Format: Patent
• Language: English
• Published: 28.02.2008
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION

PROBLEM TO BE SOLVED: To control input and output waveforms to sine waves while reducing a common mode voltage and harmonics of input and output voltages even if an output line voltage command value is in a high-output/low-output voltage region and suppressing pulsation. SOLUTION: The PWM control of the bi-directional switch of an AC-DC direct converter 3 is performed by a direct AC-AC conversion type spatial vector modulation method. The state of a basic vector obtained by developing a line voltage of a three-phase AC output on a two-phase static αβ axis is six simple oscillation vectors VXmax, VXmid, VXmin, VYmax, VYmid and VYmin and a zero vector Vz, and the Vol* selects five different spatial vectors in a low output voltage region and a high output voltage region with a region BL as a border out of an input voltage detection value Vi and an output current detection value Io. When the Vol* is in the high output voltage region, the spatial vector is selected from seven patterns of combinations satisfying conditions. COPYRIGHT: (C)2008,JPO&INPIT