Digital Control Strategy for Input-Series-Output-Parallel Modular DC/DC Converters

In this paper, an input-series auxiliary power supply scheme is proposed, which is suitable for high input voltage and multiple-output applications. The power supply scheme is based on a two-transistor forward topology, all of the series modules have a common duty ratio, all the switches are turned on and off simultaneously, and the whole circuit has a single power transformer. It does not require an additional controller but still achieves efficient input voltage sharing (IVS) for each series module through its inherent transformer-integration strategy. The IVS process of this power supply scheme is analyzed in detail and the design considerations for the related parameters are given. Finally, a 100W multiple-output auxiliary power supply prototype is built, and the experimental results verify the feasibility of the proposed scheme and the validity of the theoretical analysis.

Section: B the Ivs Processmentioning

confidence: 99%

Input-Series Multiple-Output Auxiliary Power Supply Scheme Based on Transformer-Integration for High-Input-Voltage Applications

Tao¹,

Ben²,

Wei³

2012

“…Actually, these schemes [3]- [9] can be classified as input voltage control methods. The individual input voltages need to be sensed with many voltage sensors.…”

Section: Introductionmentioning

confidence: 99%

“…The master/slave control [7] and the uniform voltage distribution [8] are adopted for ISOP converters to realize IVS. The neighboring input voltages sharing method [9] is implemented for ISOP converters. The strategies in [2]- [9] allow the configuration to achieve IVS, but the input voltage of each module has to be sensed.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Input Voltage Sharing Control for Input-Series-Output-Parallel DC-DC Converters without Input Voltage Sensors

Guo¹,

Sha²,

Liao³

2012

Self Cite

Input-series-output-parallel (ISOP) modular converters consisting of multiple modular DC/DC converters can enable low voltage rating switches for use in high voltage input applications. In this paper, an input voltage sharing control strategy for input-series-output-parallel (ISOP) full-bridge (FB) DC/DC converters is proposed. By sensing the difference in the input current of two modules, the system can achieve input voltage sharing for DC-DC modules. The effectiveness of the proposed control strategy is verified by simulation and experimental results obtained with a 200w-50kHz prototype.

“…As a result, it is unnecessary to implement both IVS and OCS control. A decoupling IVS control scheme [10]- [12], master/slave control [13] and uniform input voltage distribution control [14] for ISOP converters have been implemented with IVS loops without sensing the output currents at all. Sensorless current mode control is effective for an ISOP system [16], but component tolerances will lead to unbalanced voltage sharing among the modules.…”

Section: Introductionmentioning

confidence: 99%

DSP Based Series-Parallel Connected Two Full-Bridge DC-DC Converter with Interleaving Output Current Sharing

Sha¹,

Guo²,

Liao³

2010

Self Cite

Input-series-output-parallel (ISOP) connected DC-DC converters enable low voltage rating switches to be used in high voltage input applications. In this paper, a DSP is adopted to generate digital phase-shifted PWM signals and to fulfill the closed-loop control function for ISOP connected two full-bridge DC-DC converters. Moreover, a stable output current sharing control strategy is proposed for the system, with which equal sharing of the input voltage and the load current can be achieved without any input voltage control loops. Based on small signal analysis with the state space average method, a loop gain design with the proposed scheme is made. Compared with the conventional IVS scheme, the proposed strategy leads to simplification of the output voltage regulator design and better static and dynamic responses. The effectiveness of the proposed control strategy is verified by the simulation and experimental results of an ISOP system made up of two full-bridge DC-DC converters.