| Based on an overview of high-frequency link (HFL) inverters, the advantages and disadvantages of HFL inverters in some important voltage mode and current mode are discussed in the dissertation. The current mode HFL inverters solve the inherent voltage surge problem in voltage mode HFL inverters, so they have better performance and application prospect in low power applications. From the view point of the whole topologies of current mode HFL inverters, two topologies of half-bridge and push-pull current mode HFL inverters are proposed, which are composed of four power switches. HFL Inverters in discontinuous current mode (DCM) are extended to those in continuous current mode (CCM).The half-bridge bi-directional current mode HFL inverter can realize DC to AC conversion in only one stage. The half-bridge bi-directional current mode HFL inverter succeeds to the advantages of full-bridge HFL inverter but uses fewer power switches, which reduces the costs of switches' driver circuit. Two kinds of common used snubber circuits are studied through simulation and experiment. It is pointed out that the RCD snubber has less power loss. Increasing the turn ratio of transformer is helpful for the energy, which is stored in the primary side of transformer, to be transferred to the secondary side. Therefore, the conversion efficiency of this inverter has been improved. But it also increases the stress of the secondary side power switches. So the turn ratio should be chosen properly with the consideration of both aspects. The 500VA experimental prototype of aero static inverter has the advantages of flat volt-ampere characteristic, small THD of output sinusoid voltage, high efficiency, small size, light weight and low cost. The voltage of bridge capacitor will become unbalanced, when inverter's input side is a single source. This phenomenon is inherent with the control of voltage feedback. A balance winding can overcome this shortcoming and widen the application of this circuit.Push-pull current mode HFL inverter also is composed of four power switches. The simulation and experiment of a 500VA experimental prototype indicates that this circuit has the advantages of less components, simple topology, the ability of four quadrant operation and high efficiency. The inverter does not need the symmetry of the components' parameters and can be applied to DC to AC conversion with single low input voltage source. Like the half-bridge HFL inverter, the output side of push-pull HFL inverter can be no load, resistance load or inductance load. When the input voltage varies from 40V to 60V and the output side varies from no load to rated resistance load, the output voltage will vary within 1.3% with the THD of less than 2% and the highest efficiency of 86.3%. Different distribution of power loss can be worked out by MathCAD software based on the formula reasoning. The result of calculation is consistent with that of the experiment, which proves that this method is right. It is pointed out through the analysis of calculating data that the key to improve efficiency at the same output power is to decrease the peak current and rms current of power switches or the on-resistance of MOSFET and windings.HFL Inverters in discontinuous current mode (DCM) are extended to those in continuous current mode (CCM), which is very important for improving the conversion efficiency. The reason is that the peak current and rms current of power switches can be reduced sharply. The size of transformer increases for the reason of primary inductance's value rising in CCM. However, the result of the simulation, in which all the parameters are kept constant except the primary and secondary inductance, is that 3% higher conversionefficiency can be achieved in CCM than in DCM. The experiment result shows that conversion efficiency in CCM is improved by 2 percent compared with that in DCM, although the on-resistance of winding in CCM is more than that in DCM. The analysis of open-loop transfer function in both DCM and CCM shows that pull-push HFL inverte...
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