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Switched-mode power supplies (SMPS) are becoming an essential part of many electronic systems as the industry drives toward miniaturization and energy efficiency. However, practical SMPS design courses are seldom offered. In this paper, a generalized MATLAB/SIMULINK modeling technique is first presented. A proposed practical SMPS design course at Lunghua University, Taiwan, which incorporates this technique, is then described. In order to validate the correctness of the proposed modeling technique, four prototype SMPS are provided in this paper. These prototype circuits also serve as the laboratory section of the proposed course. The main objective of the course is to teach final-year undergraduate students and first-year Master's students how to design an SMPS in real life. The positive response from students indicates that the proposed technique is useful for SMPS design courses. (Contains 3 tables and 28 figures.)

Summary: This article proposes an active balancer, which features bidirectional charge shuttling and adaptive equalization current control, to fast counterbalance the state of charge (SOC) of cells in a lithium‐ion battery (LIB) string. The power circuit consists of certain bidirectional buck‐boost converters to transfer energy among the different cells back and forth. Owing to the characterization of the open‐circuit voltage (OCV) vs SOC in LIB being relatively smooth near the SOC middle range, the SOC‐inspected balance strategy can achieve more precise and efficient equilibrium than the voltage‐based control. Accordingly, a compensated OCV‐based SOC estimation is put forward to take into account the discrepancy of SOC estimation. Besides, the varied‐duty‐cycle (VDC) and curve‐fitting modulation (CFM) methods are devised herein to tackle the problems of slow equalization rate and low balance efficacy, which arise from the diminution in balancing current as the SOC difference between the cells decreases in the later duration of equalization especially. The proposed strategies have taken the battery nonlinear characteristic and circuit parameter nonideality into account and can adaptively modulate the duty cycle with the SOC difference to keep balancing current constant throughout the balancing cycle. Simulated and experimental results are given to demonstrate the feasibility and effectiveness of the same prototype constructed. Compared with the fixed duty cycle and the VDC methods, the proposed CFM has the best balancing efficiency of 81.4%, and the balance time is shortened by 27.1% and 18.6%, respectively. [ABSTRACT FROM AUTHOR]