Performance comparison of output power estimators used in AC/DC/AC converters

摘要

In the paper various methods of power estimation used in AC/DC/AC converters are compared. To maintain constant DC bus voltage using only small electrolytic capacitors which is one of the design targets in these systems, the input bridge reference currents must be generated on the basis of the system power flow. Since this method is not sufficient for tight regulation, an inner DC bus voltage control loop is usually added. The design procedure of the DC bus voltage regulator is also presented. The performance of three estimation methods is compared in terms of DC bus voltage fluctuation in dynamic conditions for a 15 kW AC/DC/AC converter.