Experimental Validations of the SiC MOSFET based LLC Converter Circuit and Power Loss Models

The flyback converter has been widely used in Photovoltaic microinverters, operating either in Discontinuous, Boundary, or Continuous Conduction Mode (DCM, BCM, CCM). The recently proposed hybrid DBCM operation inherits the merits of both DCM and BCM. In this work, the necessary analytical equations describing the converter operation for any given condition under DBCM are derived, and are needed due to the hybrid nature of the modulation strategy during each sinusoidal wave. Based on this analysis, a design optimization sequence used to maximize the weighted efficiency of the inverter under DBCM is then applied. The design procedure is based on a power loss analysis for each converter component and focuses on the appropriate selection of the converter parameters. To achieve this, accurate, fully parameterized loss models of the converter components are implemented. The power loss analysis is then validated by applying the optimization methodology to build an experimental prototype operating in DBCM.

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A Thermomechanical Approach to Tire Power Loss Modeling

Tire Science and Technology ◽

10.2346/1.2151023 ◽

1981 ◽

Vol 9 (1) ◽

pp. 3-18 ◽

Cited By ~ 24

Author(s):

D. Whicker ◽

A. L. Browne ◽

D. J. Segalman ◽

L. E. Wickliffe

Keyword(s):

Analytical Model ◽

Fuel Economy ◽

Power Loss ◽

Thermal State ◽

Constitutive Theory ◽

Conceptual Basis ◽

Loss Model ◽

Preliminary Results ◽

Loss Models ◽

Loss Modeling

Abstract The increasing emphasis on improving fuel economy has created a need for a good analytical model for predicting tire power loss. Some of the existing tire power loss models are first reviewed and deficiencies noted, principal among these being the constitutive theory used to characterize tire materials, the model for the tire-pavement interaction, the model to account for the changing thermal state of the tire, and the model representing the interaction between the thermal and the mechanical states of the tire. The characteristics of an ideal power loss model are then outlined, its conceptual basis is presented, and the specific tasks needed to develop it and eliminate the previously listed deficiencies are discussed. Required experimental inputs to the model are enumerated. Finally, preliminary results are presented which demonstrate the feasibility of the approach.

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Power Loss Analysis and a Control Strategy of an Active Cell Balancing System Based on a Bidirectional Flyback Converter

Applied Sciences ◽

10.3390/app10124380 ◽

2020 ◽

Vol 10 (12) ◽

pp. 4380

Author(s):

Yu-Lin Lee ◽

Chang-Hua Lin ◽

Shih-Jen Yang

Keyword(s):

Metal Oxide ◽

Control Strategy ◽

Power Loss ◽

Metal Oxide Semiconductor ◽

Active Cell ◽

Oxide Semiconductor ◽

Flyback Converter ◽

Loss Analysis ◽

Loss Models ◽

Cell Balancing

This research proposes a power loss analysis and a control strategy of an active cell balancing system based on a bidirectional flyback converter. The system aims to achieve an energy storage application with cells connected in 6 series and 1 parrarel (6S1P) design. To reduce the structural complexity, Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) array commonly used in balancing system is replaced with the photovoltaic Metal-Oxide-Semiconductor (photoMOS) array. Power loss analysis is utilized for the system operating in the proper current to reach higher efficiency. The proposed loss models are divided into conduction loss, switching loss, and copper and core loss of the transformer. Besides, the models are used to estimate the loss of converter operating in different balance conditions to evaluate the system efficiency and verified by the implemented balancing circuit. By way of the loss models, the balancing current can be determined to reach higher efficiency of the proposed system. For further improvement of the balancing process, the system has also applied a control strategy to enhance the balancing performance that reduces 50% maximum voltage difference than traditional cell-to-pack architecture, and 47% balancing duration than traditional pack-to-cell architecture.

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