Discontinuous Current Mode Control Research Articles

Operation Characteristics of Discontinuous Current Mode for a Dual-Active-Bridge AC-DC Converter with an Active Energy Buffer

This paper discusses operation characteristics of discontinuous current mode (DCM) for an ac-dc isolated converter for on-board battery chargers of electric vehicles. The converter discussed in this paper consists of a front-end diode-bridge rectifier, an active energy buffer, and a dual-active-bridge dc-dc converter. The energy buffer circuit absorbs the power pulsation form the single-phase ac line into a small-rated capacitor, and thus, makes it possible to reduce a required capacitance of the dc-link capacitor. This paper explains details of the DCM control method including a technique of the ripple cancel of the inductor current, to realize the power factor correction of the line current and the voltage control of the buffer capacitor at the same time without complex calculations. Then, a reference value of the inductor current and an operation range of the dc-output voltage are discussed. Experimental results obtained by a 220-V, 6.6-kW experimental setup demonstrate a sinusoidal-line current and a controlled buffer capacitor voltage as well as a smoothed dc-output current.

Discontinuous Current Mode Control for Minimization of Three-phase Grid-Tied Inverters in Photovoltaic System

Discontinuous Current Mode Control for Minimization of Three-phase Grid-Tied Inverters in Photovoltaic System

Charging and discharging model of lithium-ion battery for charge equalization control using particle swarm optimization algorithm

This study presents a charging and discharging controller of a lithium-ion battery for charge equalization control of a battery storage system using the particle swarm optimization (PSO) algorithm. The charge equalization controller is designed using a bidirectional flyback DC–DC converter for exchanging the amount of energy from a battery series stack to an overdischarged cell to be charged and vice versa. The constant current–constant voltage charge proportional–integral (PI) control and discontinuous current mode control are applied to charge and discharge the lithium-ion battery on a flyback converter operation. This proposed system utilizes the PSO algorithm to optimize the values of the PI controller parameters. Optimization results produce the ideal values of the PI controller parameters with minimum error indices, thereby regulating the pulse-width modulation to the MOSFET switching drive of the flyback converter and upgrading the battery charge performance for charge equalization. The PSO algorithmic approach-based developed system is proven to be robust and competent for high-tech storage systems toward the advancement of sustainable electric vehicle technologies and renewable source of applications.

Novel PFC converter suitable for engine-driven generator-interactive three-phase power systems

In recent years, discontinuous current mode control implementation for three-phase AC–DC converters with active power filtering and power factor correction schemes has attracted special interest in industrial and telecommunication energy systems. This control strategy has practical advantages since it has a simple and cost-effective configuration. However, for emergency engine-driven generators, most three-phase PFC converters with discontinuous current mode control have not been effectively adopted in practice because the conventional PFC circuit configuration has some disadvantages for engine-driven generators connected to three-phase AC mains. A new conceptual PFC converter circuit and system configuration operating with discontinuous current mode control and suitable for engine-driven generators connected to three-phase AC mains is proposed. The operating principle and unique features of the proposed PFC converter is discussed in terms of harmonic currents and PFC converter performance evaluations on the basis of simulation results from two types of conventional three-phase PFC converters.