CONTROLLING METHOD AND DEVICE FOR PARALLEL OPERATION OF INVERTER, AND UNINTERRUPTIBLE POWER SUPPLY DEVICE

• Main Authors: YAMATO IKUO, SAKURAI YOSHIMI, INUKAI SATORU, SHIRAHAMA HIDEFUMI, MINO TOMOAKI
• Format: Patent
• Language: English
• Published: 18.03.1994
• Edition: 5
• 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; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; SYSTEMS FOR STORING ELECTRIC ENERGY

PURPOSE:To make it possible to suppress cross currents flowing among plurality of inverters surely. CONSTITUTION:In the case of operating inverters 2c and 3c in parallel, the output currents of the inverters 2c and 3c are detected with current detectors 20 and 21 respectively, and the deviations of the detected values are found by adders 24 and 27 respectively as cross currents DELTAI1 and DELTAI2. Cross current suppressing signals DELTAD1 and DELTAD2 for suppressing cross currents DELTAI1 and DELTAI2 to zero are produced by cross current suppressing circuits 12 and 13. And duty commands D10 and D20 provided on the basis of voltage waveform commands Vrl and Vr2 are corrected with adders 22 and 26 according to the cross current suppressing signals DELTAD1 and DELTAD2, and the output voltages of the inverters 2C are 3C are controlled according to the corrected duty commands D1 and D2.