| Power Electronic Systems Integration (PESI), a key research area in modern power electronics, pushes the power electronic techniques towards integration, standardization and modularization. To develop the technology of high integrated Standard Power Modules (SPM) is the important work for PESI, and it is also the key factor to make it possible that the PESI is applied in the industry successfully. Classification for the SPM, rules for topology selection, soft-switching technology for SPM, topology selection and improvement for SPM, flexible converter theory, and consideration for small-signal in SPM are studied in this dissertation, and several novel ideas are presented.PESI technology is developed in order to be applied in the mainstream power electronics products in the world. The investigation and analysis for the mainstream power electronics products are carried out, and the requirements, architectures, and features of them are proposed. SPMs are classified into 14 categories by the way of both voltage level and power level, according to practical applications. Based upon electrical specifications, four novel selection criterions of DC/DC topologies in designing power products are presented. Some classical and novel excellent topologies are evaluated according to these four criterions. Then the relation between electrical specification and DC/DC topologies is presented for power product designer to use conveniently.The needed soft-switching technology for SPM is analysis, and the conception and theory of control-type soft-switching technology are proposed for mid-to-low power or mid power applications. It clears up the definition of control-type soft-switching and presents five characteristics for control-type soft-switching in the paper. The theory of five characteristics is verified in the existing control-type soft-switching topologies. And a series of new control-type soft-switching topologies are constructed by using the theory of five characteristics. For low power SPM applications, the soft-switching converter of quasi-resonant flyback is introduced.According to the special requirements of PESI, Some classical PWM converters, which are the candidate topologies for SPMs, are improved. First of all, a novel topology of wide range dual-switch flyback converter, extending the available duty cycle, is proposed for high voltage low power SPM applications. Second, for low-to-mid power SPM applications, a family of wide rang dual-switch forward converters, including 3 kind of asymmetrical topologies, are proposed. The control-type soft-switching technologies are developed for the two asymmetrical topologies thereinto. At last, paper presents a synchronous rectifier driving scheme, which not only solves the problem of short circuit when modules run in parallel but also keeps synchronous rectifier driving performance same as that of self-driven for low voltage high current SPM applications.According to the special requirements of PESI, Some classical resonant converters, which are the candidate topologies for SPMs, are improved. The developing course of LLC-4 is introduced, and the detailed operating principle is analyzed based on the non-isolated LLC-4 topology. The examples that LLC-4 is applied in the practical products of LCD power and POE are presented. Three-level LLC-4 with four dead times is proposed for high input voltage applications such as the DC/DC SPMs after three-phase rectifier. Voltage doubler LLC-4 is proposed for high output voltage SPM applications. To further decrease the voltage stresses of the secondary side components, LLC-4 with minimized voltage stress for secondary side is proposed. In this topology, voltage stresses of secondary side diodes and secondary side capacitors are half of output voltages. A simple architecture of LLC-4 with half-wave rectifier is proposed. Multi-output LLC-4 including this architecture is named asymmetrical multi-output LLC-4. It is fit for multi-output SPMs with expansibility applications. Strategy of time-sharing magamp is adopted in LLC-4 with multi-output for increasing the adaptability of the very topology to such application as multi-output with high cross-regulation requirement. For high power, low voltage high current input or output SPM application, interleaving LLC-4 is proposed, in which, input current or output current can be ameliorated from DCM to CCM. Simulations or experiments are performed for all the above topologies. Finally, various input topologies and output topologies for LLC-4 are summed up.In order to further improve the wide range adaptability of SPM, a novel conception of flexible converter and its theory are proposed. The conception of topology subset is cleared up, and 4 examples of topology subset are presented. Switching point and switching mode for the flexible converter are studied in this dissertation. An example of flexible converter with two selectable topologies is presented, and verified in an experimental prototype. The compatible issue of small signal is presented and solved as well.Useful methods of measurement and analysis for small-signal in power electronics are introduced. "Enlarging the width of mid frequency part" and "moving the gain bode plot of compensation network" are proposed for slightly adjusting the small-signal performance. For wide voltage range input Buck converter, a method is proposed that input voltage is used as compensation value to balance the value of Vin in the transfer function of the power stage. Thus, loop gain will not change at various input voltage, and not only good stability but also good dynamic performance can be achieved in wide input voltage range applications. For wide voltage range output Buck converter, various ways to adjust the output voltage are analyzed. The way can adjust the output voltage but will not influence the small signal transfer function is proposed. Thus, the loop gain will not change at various output voltage. Finally the small-signal issues of flexible converters are discussed, and the related solutions are proposed as well.
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