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This article deals with the negative effects produced by unexpected energy of solar array and methods of suppressing the effects for the sequential switching shunt regulator (S3R). The complex space operation conditions, such as plasma environment and accidental impact are likely to cause abnormal discharge of solar array, leading to unexpected changes in the input energy of an S3R. Effects of unexpected energy on current stress and power loss of power devices, overregulation of the S3R and quality of output voltage are represented and analyzed in this article. A shunt regulator (SR) topology based on the switch current limiting drive is then proposed to suppress current stress and power loss of power devices, thereby alleviating negative effects. Finally, simulation and experimental results are provided to illustrate the negative effects of unexpected energy and validate the proposed SR. [ABSTRACT FROM AUTHOR]

This article presents an integrated magnetic buck–boost converter (IMBBC) with a positive output voltage. The input inductor, two power transfer inductors, and an auxiliary inductor in the ripple cancellation network of this converter are integrated in one magnetic core, and an additional capacitor is included for output current ripple cancellation. The IMBBC inherently operates in the continuous conduction mode and exhibits a nonpulsating input current and a very low ripple output current, thereby not only decreasing the current stress on both the input and output capacitors but also reducing the output voltage ripple. Because the input of the IMBBC is connected to the output during the switch-on period (similar to the operation of buck converters), the proposed IMBBC overcomes the right-half-plane zero problem in the buck or boost mode, thus achieving a higher dynamic performance. The use of the magnetic integration technique not only helped realize the aforementioned performance, but can also help reduce the weight and volume of dc–dc converters. Finally, the feasibility and effectiveness of the proposed topology and design approaches are experimentally verified. [ABSTRACT FROM AUTHOR]

Sequential switching shunt regulators (S3Rs) are widely used in the satellites owing to their simple structure and high reliability. The high-power communication satellites require a power supply with a high bus voltage and large solar array section current. However, a large solar array capacitance and new time-division multiple access operations complicate the design of a lightweight and cost-effective power supply by increasing the difficulty in dissipation and thermal control. On the basis of passive current limitation, in this article, we propose a novel shunt regulator with only one output diode and a protection strategy to achieve high efficiency, appropriate shunt current limitation, and low turn-off delay. In addition, to reduce the dissipation of an S3R cell when feeding the solar array current to the main bus and to satisfy the single point failure-free requirement, an innovative self-retriggerable diode short-circuit fault detector circuit is proposed, which includes a protection switch for a safe thermal or electrical operation. Finally, simulation and experimental results are presented to validate the proposed shunt regulator and the corresponding control method or protection strategy. [ABSTRACT FROM AUTHOR]

A new bidirectional LCLL-type resonant dc-dc converter (LCLL-BDC) is proposed in this article, which features a wide output voltage range for both ports, thus achieving zero-voltage switching (ZVS) at the input side and zero-current switching (ZCS) at the output side. The snubberless converter is similar to the type-11 LLC-type resonant converter, with the exception of an additional inductor. The auxiliary inductor allows for the converter to achieve a wide voltage range power transfer, thus addressing the inability of the LLC-type converter to be boosted in the reverse mode. The equivalent model and the steady-state operation are presented in this article. Moreover, the design methodology for the resonant network was derived for the LCLL-BDC. A 1-kW prototype, which interfaces two batteries of different energy systems, was developed to verify the validity and applicability of the proposed converter. The input and output voltage range was found to be 80–120 V, and the highest efficiencies for the bidirectional operational modes exceeded 96%. [ABSTRACT FROM AUTHOR]

This paper presents a novel integrated magnetic three-port converter (IMTPC) with high power density and all three ports’ current ripple cancellation. The proposed IMTPC can interface one PV port, one bidirectional battery port, and one load port of the PV-battery dc power system. Only two high power magnetic devices are needed in an IMTPC for realizing power conversion, ripple cancellation, and switch driver simultaneously. Three extra capacitors were added to achieve three ports’ current ripple cancellation. Therefore, the port of the IMTPC will always in continuous-conduction mode with “zero current ripple,” thus, size of passive filter can be reduced and accuracy of maximum power point tracking can be improved. Meanwhile, simple driving of the high-side switch can be realized by integrated magnetic winding, which is responsible for MOSFET driver's voltage level shift. The using of the integrated magnetic technique not only performs aforementioned advantages but also shows great potential for reducing the weight and volume of the dc–dc converter. Finally, experimental verifications are given to illustrate the feasibility and effectiveness of the proposed topology and control method. [ABSTRACT FROM PUBLISHER]

A photovoltaic (PV)-based stand-alone power system is usually used to manage the energy supplied from several power sources such as PV solar arrays and battery and deliver a continuous power to the users in an appropriate form. Traditionally, three different dc/dc converters would have been used. To reduce the cost and improve the power density of the power system, an integrated solution of PV isolated dc/dc three-port converter (TPC) is proposed in this paper. Zero current switching can be achieved for all main diodes and MOSFETs to improve the efficiency, and a continuous input current of solar array is maintained by adding a magnetic switch derived from a fourth winding of the half-bridge transformer. Based on the energy-balancing part formed by boost, the control methods for the single module to realize maximum power point tracking (MPPT), battery charge control, and main bus regulation are proposed. The power system control method for multimodules in parallel is also derived, and the operation of the TPC power system can be transited between conductance mode and MPPT mode automatically. Finally, the experimental results verify that the proposed TPC, together with the proposed control method, meets the requirements of a high-power-density stand-alone PV-battery power system. [ABSTRACT FROM PUBLISHER]