Research On Topology And Control Method For Single-Inductor Multiple-Output Converters

Computers and some electronic equipment usually require multiple levels of supply voltage. It will increase the equipment's size and cost if each level of supply voltage is provided by independent converters. However, the multiple-output converter can solve this problem.The conventional multiple-output switching converter has excessive magnetic components and large size. Importantly, there is serious cross-regulation among the outputs. Single-inductor multiple-output (SIMO) converter with only one inductor benefits with significant overall cost saving, small size and light weight of equipment and device, which make it as one of the most suitable and cost-effective solution for multiple output power supplies. SIMO converter's topology and control method attracted widespread attention of academia and industry, and it has become an important research topic.At present, the study of SIMO converter is focusing on the non-isolated topologies and the control methods. A nonlinear control technique, pulse train (PT) control technique is applied for control of non-isolated topology of SIMO converter in discontinuous conduction mode (DCM). The features of current mode and voltage mode of PT control are studied in detail. To avoid cross-regulation between each output of converter, time-multiplexing scheme is used to determine which output should be controlled in the time interval of time-multiplexing signal. A "blank pulse" is adopted to improve the transient performance and power conversion efficiency in light load. Error amplifier and corresponding compensators as required by conventional current mode pulse width modulation (PWM) technique are needless in PT control technique. Therefore, the control technique proposed in this thesis is simple and exhibites fast dynamic response. Simulation and experimental results for single-inductor multiple-output (SIDO) buck converter are presented to verify the proposed technique.A family of isolated SIMO dc-dc flyback converters is derived in the thesis, and achieved its control in DCM by using PT control method. Each outputs of converter can achieve independent regulation in this control method. Simulation and experimental results for SIDO flyback converter are presented to verify the validity of the topologies and control method.