| 摘要 |
PROBLEM TO BE SOLVED: To provide a three-level power conversion device that can suppress a variation in neutral potential even when operated as a reactive power regulation device.SOLUTION: The three-level power conversion device includes: first and second three-level converters 2A, 2B connected to an AC power system; positive and negative DC capacitors 3P, 3N; a three-level inverter 4 for driving an AC motor 5; and converter control means 10 for controlling the three-level converters 2A, 2B. The converter control means 10 has: first and second reactive current control means 15A, 15B for controlling reactive components of input currents to the three-level converters 2A, 2B to predetermined reactive current standards, respectively; first and second neutral potential variation suppression means for controlling PWM control means 17A, 17B to bring a difference between voltages applied to the DC capacitors 3P, 3N to zero; and active current control means for causing a predetermined circulating active current from the three-level converter 2A to the three-level converter 2B via a DC link. |
