This paper presents a control approach for paralleling the UPS inverters with no control interconnection. The inference voltage of the inverter is generated to simulate a reactor connected between the inverter and the load at the fundamental frequency. The intention is to control the real and reactive power sharing of the inverters with the Q-V and P-ω droop scheme without connection of a true transfer reactor. At the harmonic frequency the reference voltage turns to simulate a resistor, aiming that the load harmonic current can be shared equally and the voltage distortion is low. Two 1KVA inverters are setup for demonstrating the effectiveness of the proposed approach.
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