Research On Parameters And Novel Topology Of DC/DC Converter In SMPS

DC/DC converter is an important part of SMPS system and it has rich nonlinear dynamical characteristic when circuit parameters and circuit topology changed, which could affect the stability and performance characterists of system. The influence of circuit parameters of DC/DC converter on stability of SMPS system were researched in the thesis. The research results could provide the basis for the design of parameters when DC/DC converter applied to SMPS system. As DC/DC converter could not be applied to all occasions, a novel circuit topology for DC/DC converter was developed. The circuit principle, parameters characteristic and parameter design method were studied in detail and verified in experiments.The main contents and innovative research in the dissertation were summarized as follows:1. Zero error simulation model of voltage control BUCK converter was constructed based on the exact state equations of BUCK converter. The influence of different parameters on the stability of VCBUCK converter was researched. The results proved that stability of VCBUCK converter was senstive to input voltage, storage inductor, output filter capacitor, scale factor but not to integration factor and load.2. Voltage control double-ended DC/DC converter was equivalent to doubled-switch frequency VCBUCK converter based on its switch modes. According to the equvialent simulation model of VCBUCK converter the influence of different parameters on the stability of voltage control double-ended DC/DC converter were researched. The results verified that the influence characteristic of parameters on it was similar to VCBUCK converter.3. Double loop simulation model of current control BUCK converter was constructed, based on which the stability of CCBUCK was studied in different parameters. The experiments verified that stability of PCCBUCK converter was senstive to input voltage, output filter capacitor, and scale factor but not to integration factor, storage inductor and load. And the stability of VCCBUCK converter was senstive to input voltage, storage inductor, output filter capacitor, scale factor but not to integration factor and load. The influence characteristic of input voltage on PCCBUCK converter and VCCBUCK converter were contrary.4. Double loop simulation model of current control BOOST converter was constructed based on the exact state equations of BOOST converter. The influences of different parameters on the stability of CCBOOST converter were researched. The results proved that input voltage was the vital parameter to stability of CCBOOST converter. With variation of input voltage the system operation state transferred from 1-period to chaos through double period bifurcation. And the influence characteristic of input voltage on PCCBOOST converter and VCCBOOST converter were contrary. Other parameters had no impact on stability of CCBOOST converter.5. A novel converter topology, namely parallel resonant dual voltage converter was developed. The operation modes, parameter characteristic and parameter optimization design method of PRDVC were researched in detail based on its circuit topoloty and state equations. Results showed that PRDVC had many merits compared to other converters, which were listed below.â‘ The switch frequency and efficiency were improved by using soft switch which was accquired by resonant technology.â‘¡Distributed capacitor and leakage indcutor in high frequency transformer were absorbed by PRDVC topolgy. The influence of distributed parameters was reduced in order to improve EMC and reliability of system.â‘¢Dual voltage rectifying circuit and transformer were both used to boost voltage. Therefore, the problems of bigger volume and heavy degree of difficuity in making were solved, which was suitable for miniaturization high-voltage power supply.The experiments were performed to verify the research contents and the corresponding waveforms had been presented. The experiment results showed that the theory analysis and simulations were consistent with the experiments. The methods and achievements in the dissertation have the practical value.