Design Of LLC Resonant Converters

It is very available to reduce the volume and weight of converter, improve the total efficiency and power density with higher operation frequency. Considering from realization, resonant converter has the advantage of higher operation frequency, lower switching loss, wider range of input voltage, higher efficiency, lighter weight, smaller volume, smaller EMI, lower switching stress to PWM converter. Also for LLC resonant converter, it can wok well without any load and the current through resonant network is response to the variation on load. Just with these advantages comparing to other resonant converter, it can be widely used in the case of high switching frequency.LLC resonant converter is developed on the base of two components resonant converter by adding a parallel inductance, so its DC gain characteristic is better to series resonant converter or parallel resonant converter. But on the other hand, it is more complex to control the operation, the output, and the design of parameters of converter. For these problems faced to when designing LLC resonant converter, it is necessary to put forward a suit of method directing design of parameters.This thesis discuss DC gain characteristic on each frequency range, especially focusing on the comprehension of physics meaning of the converter. By concluding the influence brought on the converter by several parameters, I put forward the method of designing parameters of converter. Subsequently, much experimental data is given to testify the validity of the design method. Also do some loss analysis on the converter so as to find the way to improve the efficiency of converter. At last, I do some attempt on the magnetic integration of converter, and give experimental result to show its validity.