The Research Of DC-AC Inverter Based On Energy Control

DC-AC converter is used more and more widely in modern days. The converter with high quality electric power ensures the safety of some equipments and the high quality of the product. Especially as equipment, such as complex equipment, exact apparatus and equipment sensitive to quality electric power, becomes popular the quality electric power is required much higher. But the DC-AC converter used now has high THD, or in order to get lower THD, a big filter is needed in the system. And both the cost and the cubage are high. So it becomes popular to research the DC-AC converter with low THD, small cubage, and high quality electric power.This DC-AC converter is made up of the same basic two Buck-Boost DC-DC inverters. Adopting the energy control method as control strategy, the circuit can get smoother sinusoidal output wave, compared with the other DC-AC converter in the same situation.The energy control method thinks that energy transfers forward from input to output, or backward from output to input constantly. And in the process of transfer, the energy which can make the output voltage follow the reference voltage will be calculated accurately. According to this calculated result and the sampling result, the switch will be on or off. In this way the energy transferred from DC side to AC side can be controlled accurately. Compared with converters without filter circuit, this system has low THD and high quality of electric power.Adopting the energy control method into a circuit composed of two DC-DC inverters. This paper will do the simulation and discuss how to do the real circuit experiment.