THREE-PHASE AC POWER SUPPLY SYSTEM AND CONTROL METHOD OF THREE-PHASE AC POWER SUPPLY SYSTEM

摘要

To provide a three-phase power supply system improving current balance of commercial three-phase without stopping a power supply system.SOLUTION: In a three-phase power supply system, first, second and third loads are connected, respectively, between R and S lines, between S and T lines, and between T and R lines. Furthermore, first, second and third current adjustment means are connected, respectively, between R and S lines, between S and T lines, and between T and R lines. Outputs from three current adjustment means are inputted to an inverter while coupling, and AC voltage output from the inverter is inputted to a fourth load. Output voltage control means monitors the currents of the R, S and T feeders, and calculates the line currents of respective lines and the average value thereof. Control is made to reduce the output current from the current adjustment means for connection between the lines where a current larger than the average value is flowing, and to increase the output current from the current adjustment means for connection between the lines where a current smaller than the average value is flowing.SELECTED DRAWING: Figure 1