dc.contributor.author Yu, Feng en dc.date.accessioned 2014-03-14T20:39:31Z en dc.date.available 2014-03-14T20:39:31Z en dc.date.issued 2011-05-02 en dc.identifier.other etd-06062011-165129 en dc.identifier.uri http://hdl.handle.net/10919/33458 en dc.description.abstract Various types of current mode control are being used in different applications. Model for current mode control is indispensable for proper system design. Since 1980s, modeling of current mode control has been a hot topic in power electronics field. In current mode control, sub-harmonic oscillation is a common issue, especially for constant frequency current mode control: like peak current mode control, valley current mode control, or average current mode control. Recently V2 control is becoming more and more popular due to its simple implementation ad super fast transient response. V2 control can also run into sub-harmonic oscillation just as current mode control. Efforts have been devoted to modeling of V2 control. A common property of different types of current mode control and V2 control is that they are all multi-loop structures and the inner loops are all highly nonlinear. Due to the nonlinearity of the inner loops, modeling of these structures is extremely difficult. Up to now, there are two main problems which havenâ t been solved: 1. modeling of average current mode control; 2. modeling of V2 control with composite capacitors. This thesis tries to solve these two problems and starts with V2 control. For V2 control with single type of bulk capacitors, an accurate model has been proposed previously. In this thesis, an equivalent circuit model is proposed to get better physical understanding. This method makes use of previous current mode control modeling result and relates V2 control with current mode control. To model V2 control with composite capacitors, capacitor currents and output voltage time domain waveforms are analyzed. Based on describing function method, transfer function from control to output is derived. The modeling result shows that with more parallel ceramic capacitors, system has smaller stability margin. For average current mode control, the structure is compared with V2 control. Similarity between the structures of current compensator in average current mode and output capacitor network in V2 control is identified. V2 model is utilized for average current mode control. The modeling derivation process is simplified. For the current compensator in average current mode control, it is not desired to have a high frequency pole from stability point of view. As a conclusion, a circuit model for V2 control with bulk capacitors is proposed and another two problems are examined: modeling of V2 control with composite capacitors and modeling of average current mode control. It has been demonstrated that there is similarity between these two structures. The modeling results are verified through simulation and experiments. en dc.publisher Virginia Tech en dc.relation.haspart Yu_F_T_2011_new.pdf en dc.relation.haspart Yu_F_T_2011.pdf en dc.rights In Copyright en dc.rights.uri http://rightsstatements.org/vocab/InC/1.0/ en dc.subject average current mode control en dc.subject modeling en dc.subject describing function en dc.subject V2 Control en dc.subject ripple based control en dc.subject composite capacitors en dc.title Modeling of V2 Control with Composite Capacitors and Average Current Mode Control en dc.type Thesis en dc.contributor.department Electrical and Computer Engineering en dc.description.degree Master of Science en thesis.degree.name Master of Science en thesis.degree.level masters en thesis.degree.grantor Virginia Polytechnic Institute and State University en thesis.degree.discipline Electrical and Computer Engineering en dc.contributor.committeechair Lee, Fred C. en dc.contributor.committeemember Boroyevich, Dushan en dc.contributor.committeemember Mattavelli, Paolo en dc.identifier.sourceurl http://scholar.lib.vt.edu/theses/available/etd-06062011-165129/ en dc.date.sdate 2011-06-06 en dc.date.rdate 2011-07-01 en dc.date.adate 2011-07-01 en
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